From git at osgeo.org  Mon Jun  1 09:11:58 2026
From: git at osgeo.org (git at osgeo.org)
Date: Mon,  1 Jun 2026 09:11:58 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 21d41a72a198b2a470b73dc83c6adfbcceffcbeb
Message-ID: <20260601161158.825141B61B5@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, main has been updated
       via  21d41a72a198b2a470b73dc83c6adfbcceffcbeb (commit)
      from  5ed4cd8dce266c07f962f42fa7b8fc57288067bb (commit)

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- Log -----------------------------------------------------------------
commit 21d41a72a198b2a470b73dc83c6adfbcceffcbeb
Author: Daniel Baston <dbaston at gmail.com>
Date:   Mon Jun 1 12:11:34 2026 -0400

    RectangleIntersects: guard against curved inputs (#1442)

diff --git a/src/operation/predicate/RectangleIntersects.cpp b/src/operation/predicate/RectangleIntersects.cpp
index c31fe8ce9..04fd166a8 100644
--- a/src/operation/predicate/RectangleIntersects.cpp
+++ b/src/operation/predicate/RectangleIntersects.cpp
@@ -31,9 +31,11 @@
 #include <geos/geom/Location.h>
 
 #include <geos/algorithm/locate/SimplePointInAreaLocator.h>
+#include <geos/util.h>
 
 #include <memory>
 
+
 //using namespace geos::geom::util;
 
 namespace geos {
@@ -282,6 +284,8 @@ public:
 bool
 RectangleIntersects::intersects(const geom::Geometry& geom)
 {
+    util::ensureNoCurvedComponents(geom);
+
     if(!rectEnv.intersects(geom.getEnvelopeInternal())) {
         return false;
     }
diff --git a/tests/unit/capi/GEOSIntersectsTest.cpp b/tests/unit/capi/GEOSIntersectsTest.cpp
index fe11fd70e..1beea562a 100644
--- a/tests/unit/capi/GEOSIntersectsTest.cpp
+++ b/tests/unit/capi/GEOSIntersectsTest.cpp
@@ -256,5 +256,18 @@ void object::test<13>()
     ensure_equals(GEOSIntersects(geom2_, geom1_), 0);
 }
 
+template<>
+template<>
+void object::test<14>()
+{
+    set_test_name("curved geometries not supported by RectangleIntersects");
+
+    geom1_ = fromWKT("POLYGON ((0 0, 10 0, 10 10, 0 10, 0 0))");
+    geom2_ = fromWKT("CIRCULARSTRING (5 0, 10 5, 15 0)");
+
+    ensure_equals(GEOSIntersects(geom1_, geom2_), 2);
+    ensure_equals(GEOSIntersects(geom2_, geom1_), 2);
+}
+
 } // namespace tut
 

-----------------------------------------------------------------------

Summary of changes:
 src/operation/predicate/RectangleIntersects.cpp |  4 ++++
 tests/unit/capi/GEOSIntersectsTest.cpp          | 13 +++++++++++++
 2 files changed, 17 insertions(+)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Tue Jun  2 08:52:49 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue,  2 Jun 2026 08:52:49 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 7d945a82b70a10adbba35bbd71bfcbb5f4faa27b
Message-ID: <20260602155249.8FAE91BFD42@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, main has been updated
       via  7d945a82b70a10adbba35bbd71bfcbb5f4faa27b (commit)
      from  21d41a72a198b2a470b73dc83c6adfbcceffcbeb (commit)

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- Log -----------------------------------------------------------------
commit 7d945a82b70a10adbba35bbd71bfcbb5f4faa27b
Author: Paul Ramsey <pramsey at cleverelephant.ca>
Date:   Tue Jun 2 08:51:57 2026 -0700

    Remove ASAN from MacOS builds due to hanging
    We get lots of ASAN testing in Linux

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3fddde083..568c4d4bd 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -427,11 +427,11 @@ jobs:
           runs_on: macos-14
         - xcode: "16.4"
           cxxstd: 23
-          build_type: ASAN
+          build_type: Debug
           runs_on: macos-15
         - xcode: "26.0"
           cxxstd: 23
-          build_type: ASAN
+          build_type: Release
           runs_on: macos-26
 
     runs-on: ${{ matrix.runs_on }}

-----------------------------------------------------------------------

Summary of changes:
 .github/workflows/ci.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Tue Jun  2 09:34:40 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue,  2 Jun 2026 09:34:40 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 e704204f34c95c24bfc3a8493c5cda2cbe3fe1c2
Message-ID: <20260602163440.73D771BFCF2@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, main has been updated
       via  e704204f34c95c24bfc3a8493c5cda2cbe3fe1c2 (commit)
       via  8dc21fb58a1bb744bc7ab21bc6bb7e9f0f5eab11 (commit)
      from  7d945a82b70a10adbba35bbd71bfcbb5f4faa27b (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
commit e704204f34c95c24bfc3a8493c5cda2cbe3fe1c2
Author: Paul Ramsey <pramsey at cleverelephant.ca>
Date:   Tue Jun 2 09:34:00 2026 -0700

    Remove g++15 from CI, not part of the distro repo yet

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6583f14c0..232969889 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -96,15 +96,6 @@ jobs:
           cmake: 3.31.*
           os: ubuntu-24.04
 
-        - cxx_compiler: g++-15
-          c_compiler: gcc-15
-          build_type: Debug
-          cxxstd: 20
-          arch: 64
-          packages: 'g++-15-multilib gcc-15-multilib'
-          cmake: 4.2.*
-          os: ubuntu-24.04
-
           # clang 10 and lower are not supported
           # in ubuntu 22.04 and higher
 

commit 8dc21fb58a1bb744bc7ab21bc6bb7e9f0f5eab11
Author: Paul Ramsey <pramsey at cleverelephant.ca>
Date:   Tue Jun 2 09:02:43 2026 -0700

    bump versions

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 568c4d4bd..6583f14c0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -96,6 +96,15 @@ jobs:
           cmake: 3.31.*
           os: ubuntu-24.04
 
+        - cxx_compiler: g++-15
+          c_compiler: gcc-15
+          build_type: Debug
+          cxxstd: 20
+          arch: 64
+          packages: 'g++-15-multilib gcc-15-multilib'
+          cmake: 4.2.*
+          os: ubuntu-24.04
+
           # clang 10 and lower are not supported
           # in ubuntu 22.04 and higher
 
@@ -174,6 +183,15 @@ jobs:
           cmake: 3.30.*
           os: ubuntu-24.04
 
+        - cxx_compiler: clang++-20
+          c_compiler: clang-20
+          build_type: Debug
+          cxxstd: 20
+          arch: 64
+          packages: 'clang-20'
+          cmake: 4.2.*
+          os: ubuntu-24.04
+
 
     runs-on: ${{ matrix.ci.os }}
     steps:

-----------------------------------------------------------------------

Summary of changes:
 .github/workflows/ci.yml | 9 +++++++++
 1 file changed, 9 insertions(+)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Tue Jun  2 15:31:18 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue,  2 Jun 2026 15:31:18 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch
 dependabot/github_actions/all-actions-6c4df93294 deleted.
 446752af7b7a34f4c484b7bf7f991ff8913da14e
Message-ID: <20260602223118.CB5DD1C1643@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, dependabot/github_actions/all-actions-6c4df93294 has been deleted
       was  446752af7b7a34f4c484b7bf7f991ff8913da14e

- Log -----------------------------------------------------------------
446752af7b7a34f4c484b7bf7f991ff8913da14e Bump the all-actions group with 2 updates
-----------------------------------------------------------------------


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Tue Jun  2 15:31:18 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue,  2 Jun 2026 15:31:18 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch
 dependabot/github_actions/all-actions-d30a9e7a05 created.
 3665ad79762524ee5f7c99154da58ffdb29b4fc0
Message-ID: <20260602223119.08A7D1C15D6@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, dependabot/github_actions/all-actions-d30a9e7a05 has been created
        at  3665ad79762524ee5f7c99154da58ffdb29b4fc0 (commit)

- Log -----------------------------------------------------------------
commit 3665ad79762524ee5f7c99154da58ffdb29b4fc0
Author: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Date:   Tue Jun 2 22:30:44 2026 +0000

    Bump the all-actions group across 1 directory with 4 updates
    
    Bumps the all-actions group with 4 updates in the / directory: [actions/checkout](https://github.com/actions/checkout), [vmactions/freebsd-vm](https://github.com/vmactions/freebsd-vm), [github/codeql-action](https://github.com/github/codeql-action) and [softprops/action-gh-release](https://github.com/softprops/action-gh-release).
    
    
    Updates `actions/checkout` from 6 to 6.0.2
    - [Release notes](https://github.com/actions/checkout/releases)
    - [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
    - [Commits](https://github.com/actions/checkout/compare/v6...v6.0.2)
    
    Updates `vmactions/freebsd-vm` from 1 to 1.4.5
    - [Release notes](https://github.com/vmactions/freebsd-vm/releases)
    - [Commits](https://github.com/vmactions/freebsd-vm/compare/v1...v1.4.5)
    
    Updates `github/codeql-action` from 4 to 4.36.0
    - [Release notes](https://github.com/github/codeql-action/releases)
    - [Changelog](https://github.com/github/codeql-action/blob/main/CHANGELOG.md)
    - [Commits](https://github.com/github/codeql-action/compare/v4...v4.36.0)
    
    Updates `softprops/action-gh-release` from 2 to 3
    - [Release notes](https://github.com/softprops/action-gh-release/releases)
    - [Changelog](https://github.com/softprops/action-gh-release/blob/master/CHANGELOG.md)
    - [Commits](https://github.com/softprops/action-gh-release/compare/v2...v3)
    
    ---
    updated-dependencies:
    - dependency-name: actions/checkout
      dependency-version: 6.0.2
      dependency-type: direct:production
      update-type: version-update:semver-patch
      dependency-group: all-actions
    - dependency-name: vmactions/freebsd-vm
      dependency-version: 1.4.5
      dependency-type: direct:production
      update-type: version-update:semver-minor
      dependency-group: all-actions
    - dependency-name: github/codeql-action
      dependency-version: 4.36.0
      dependency-type: direct:production
      update-type: version-update:semver-minor
      dependency-group: all-actions
    - dependency-name: softprops/action-gh-release
      dependency-version: '3'
      dependency-type: direct:production
      update-type: version-update:semver-major
      dependency-group: all-actions
    ...
    
    Signed-off-by: dependabot[bot] <support at github.com>

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 232969889..5f7a5e237 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -197,7 +197,7 @@ jobs:
         python3 -m pip install --disable-pip-version-check --user cmake==${{ matrix.ci.cmake }}
         echo "$(python3 -m site --user-base)/bin" >> $GITHUB_PATH
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -281,7 +281,7 @@ jobs:
         build_type: ['Debug', 'Release']
 
     steps:
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: 'Setup'
       uses: msys2/setup-msys2 at v2
@@ -337,7 +337,7 @@ jobs:
             arch: arm64
   
     steps:
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     # ccache not supported for this generator and/or Debug
 
@@ -378,7 +378,7 @@ jobs:
     runs-on: ${{ matrix.ci.os }}
     steps:
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -459,7 +459,7 @@ jobs:
         which clang++
         clang++ --version
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -495,7 +495,7 @@ jobs:
     name: FreeBSD
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -506,7 +506,7 @@ jobs:
         restore-keys: freebsd
 
     - name: Build and test
-      uses: vmactions/freebsd-vm at v1
+      uses: vmactions/freebsd-vm at v1.4.5
       with:
         release: "15.0"
         envs: CCACHE_COMPRESS CCACHE_COMPRESSLEVEL CCACHE_MAXSIZE
@@ -540,7 +540,7 @@ jobs:
         sudo -E apt-get autopurge -y needrestart
         sudo -E apt-get -yq --no-install-suggests --no-install-recommends install make cmake emscripten ccache
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -582,7 +582,7 @@ jobs:
         sudo -E apt-get -yq --no-install-suggests --no-install-recommends install cppcheck
         python3 -m pip install --disable-pip-version-check --user codespell
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: 'cppcheck'
       run: ./tools/cppcheck.sh
@@ -605,7 +605,7 @@ jobs:
         python3 -m pip install --disable-pip-version-check --user cmake==3.15.*
         echo "$(python3 -m site --user-base)/bin" >> $GITHUB_PATH
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
       with:
         path: geos
 
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 46eb081ac..39126ac0d 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -36,11 +36,11 @@ jobs:
         # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
 
     steps:
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init at v4
+      uses: github/codeql-action/init at v4.36.0
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -63,6 +63,6 @@ jobs:
           make -j$(nproc)
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze at v4
+      uses: github/codeql-action/analyze at v4.36.0
       with:
         category: "/language:${{matrix.language}}"
diff --git a/.github/workflows/container.yml b/.github/workflows/container.yml
index 42a93ec20..d9168c715 100644
--- a/.github/workflows/container.yml
+++ b/.github/workflows/container.yml
@@ -24,7 +24,7 @@ jobs:
 
     steps:
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Docker meta
       id: meta
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 2edbafad7..2920c83ae 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -32,7 +32,7 @@ jobs:
         uname -a
         sudo -E apt-get -yq --no-install-suggests --no-install-recommends install make doxygen
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Get tag
       id: tag
@@ -67,7 +67,7 @@ jobs:
     - name: Create Release
       if: ${{ steps.tag.outputs.tag == steps.version.outputs.geosversion }}
       id: create_release
-      uses: softprops/action-gh-release at v2
+      uses: softprops/action-gh-release at v3
       with:
         body_path: ${{ steps.notes.outputs.geosnotes }}
         name: Release ${{ steps.version.outputs.geosversion }}
diff --git a/.github/workflows/web.yml b/.github/workflows/web.yml
index c059e4210..cdd46c346 100644
--- a/.github/workflows/web.yml
+++ b/.github/workflows/web.yml
@@ -27,7 +27,7 @@ jobs:
         sudo -E apt-get -yq --no-install-suggests --no-install-recommends install make doxygen
 
     - name: 'Check Out ?'
-      uses: actions/checkout at v6
+      uses: actions/checkout at v6.0.2
 
     - name: 'Hugo Build ?'
       # ...or replace 'master' with a full version tag, such as: v0.64.1

-----------------------------------------------------------------------


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Tue Jun  9 10:52:16 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue,  9 Jun 2026 10:52:16 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 7b2e578f4444678aa081af6c484266ed2f6392bc
Message-ID: <20260609175217.BE2B31B3BDE@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, main has been updated
       via  7b2e578f4444678aa081af6c484266ed2f6392bc (commit)
      from  e704204f34c95c24bfc3a8493c5cda2cbe3fe1c2 (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
commit 7b2e578f4444678aa081af6c484266ed2f6392bc
Author: Paul Ramsey <pramsey at cleverelephant.ca>
Date:   Tue Jun 9 17:51:39 2026 +0000

    Add Arc distance test case from PostGIS

diff --git a/tests/unit/operation/distance/DistanceOpTest.cpp b/tests/unit/operation/distance/DistanceOpTest.cpp
index 7c2686773..082c91916 100644
--- a/tests/unit/operation/distance/DistanceOpTest.cpp
+++ b/tests/unit/operation/distance/DistanceOpTest.cpp
@@ -1003,6 +1003,18 @@ void object::test<51>()
     checkDistance(*g1, *g2, 0.5, 1e-6);
 }
 
+template<>
+template<>
+void object::test<52>()
+{
+    set_test_name("MultiSurface COMPOUNDCURVE and Polygon; PostGIS ticket #5989 reopened (Finnish coordinates)");
+
+    auto g1 = wktreader.read("MULTISURFACE(CURVEPOLYGON(COMPOUNDCURVE(CIRCULARSTRING(25493681.3085 6678739.6419,25493637.8256 6678776.2541,25493599.9716 6678818.6604),(25493599.9716 6678818.6604,25493583.8816 6678839.494,25493590.9591 6678844.9594,25493566.9698 6678851.9051,25493526.5793 6678861.0985,25493487.3853 6678868.2546,25493447.392 6678871.7846,25493429.5033 6678876.6846,25493435.0147 6678857.4594,25493454.9254 6678821.6192,25493452.4867 6678816.1292,25493402.3226 6678828.2153,25493354.7526 6678837.8291,25493349.0217 6678838.9873,25493310.914 6678843.6926,25493306.3784 6678859.9295,25493294.1011 6678858.7864,25493169.9028 6678847.2212,25493127.549 6678843.2773,25493057.8888 6678834.6763,25493017.4547 6678826.7261,25492928.2395 6678821.5524,25492909.1067 6678795.0681,25492946.9544 6678794.8193,25492967.1292 6678794.6866,25493010.8878 6678795.9163,25493111.5564 6678804.3109,25493113.4069 6678799.5694,25493134.2375 6678806.0729),CIRCULARSTRING(25493134.2375 6678806.0729,2549322
 3.038 6678812.0533,25493311.4919 6678802.1948,25493317.3589 6678800.9679,25493323.2107 6678799.6707),(25493323.2107 6678799.6707,25493362.6615 6678792.3924,25493364.6948 6678785.173,25493375.0512 6678781.6008,25493404.9736 6678771.2798),CIRCULARSTRING(25493404.9736 6678771.2798,25493486.8049 6678737.6728,25493566.8862 6678700.0859),(25493566.8862 6678700.0859,25493574.903 6678714.0761,25493600.2214 6678702.8803,25493654.1114 6678670.2493,25493669.7219 6678659.2147,25493677.0288 6678653.353,25493684.6468 6678648.4119,25493724.0447 6678623.7638,25493800.1925 6678583.5847,25493805.6261 6678586.1292,25493811.9258 6678582.3016,25493812.8413 6678583.0522,25493846.581 6678558.6541,25493884.2653 6678531.6272,25493900.9168 6678580.1258,25493830.7852 6678630.9518,25493789.0848 6678661.2736,25493746.1612 6678692.485,25493686.5413 6678735.8369,25493681.3085 6678739.6419))))");
+    auto g2 = wktreader.read("POLYGON ((25492929.752797972 6678919.124091367,25493008.675235115 6678876.783133076,25493098.02917443 6678854.33589699,25493139.669701554 6678977.913508233,25493122.946292613 6679011.427315322,25493050.53388224 6679068.791126598,25493140.33593199 6679140.958135231,25492931.688606273 6679401.2946243705,25492799.289171 6679295.949040241,25492651.5177725 6679115.144800108,25492929.752797972 6678919.124091367))");
+
+    checkDistance(*g1, *g2, 14.5, 1.0);
+}
+
 
 // TODO: finish the tests by adding:
 // 	LINESTRING - *all*

-----------------------------------------------------------------------

Summary of changes:
 tests/unit/operation/distance/DistanceOpTest.cpp | 12 ++++++++++++
 1 file changed, 12 insertions(+)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Wed Jun 10 00:25:45 2026
From: git at osgeo.org (git at osgeo.org)
Date: Wed, 10 Jun 2026 00:25:45 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch
 dependabot/github_actions/all-actions-d30a9e7a05 deleted.
 3665ad79762524ee5f7c99154da58ffdb29b4fc0
Message-ID: <20260610072545.530B916DF1E@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
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The branch, dependabot/github_actions/all-actions-d30a9e7a05 has been deleted
       was  3665ad79762524ee5f7c99154da58ffdb29b4fc0

- Log -----------------------------------------------------------------
3665ad79762524ee5f7c99154da58ffdb29b4fc0 Bump the all-actions group across 1 directory with 4 updates
-----------------------------------------------------------------------


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Wed Jun 10 00:25:45 2026
From: git at osgeo.org (git at osgeo.org)
Date: Wed, 10 Jun 2026 00:25:45 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 9d1676ca58c6878445b679d6b3228b96fab7d4e4
Message-ID: <20260610072545.B592016DA2D@trac.osgeo.org>

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The branch, main has been updated
       via  9d1676ca58c6878445b679d6b3228b96fab7d4e4 (commit)
      from  7b2e578f4444678aa081af6c484266ed2f6392bc (commit)

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- Log -----------------------------------------------------------------
commit 9d1676ca58c6878445b679d6b3228b96fab7d4e4
Author: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Date:   Wed Jun 10 09:25:14 2026 +0200

    Bump the all-actions group across 1 directory with 4 updates (#1443)
    
    Bumps the all-actions group with 4 updates in the / directory: [actions/checkout](https://github.com/actions/checkout), [vmactions/freebsd-vm](https://github.com/vmactions/freebsd-vm), [github/codeql-action](https://github.com/github/codeql-action) and [softprops/action-gh-release](https://github.com/softprops/action-gh-release).
    
    
    Updates `actions/checkout` from 6 to 6.0.2
    - [Release notes](https://github.com/actions/checkout/releases)
    - [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
    - [Commits](https://github.com/actions/checkout/compare/v6...v6.0.2)
    
    Updates `vmactions/freebsd-vm` from 1 to 1.4.5
    - [Release notes](https://github.com/vmactions/freebsd-vm/releases)
    - [Commits](https://github.com/vmactions/freebsd-vm/compare/v1...v1.4.5)
    
    Updates `github/codeql-action` from 4 to 4.36.0
    - [Release notes](https://github.com/github/codeql-action/releases)
    - [Changelog](https://github.com/github/codeql-action/blob/main/CHANGELOG.md)
    - [Commits](https://github.com/github/codeql-action/compare/v4...v4.36.0)
    
    Updates `softprops/action-gh-release` from 2 to 3
    - [Release notes](https://github.com/softprops/action-gh-release/releases)
    - [Changelog](https://github.com/softprops/action-gh-release/blob/master/CHANGELOG.md)
    - [Commits](https://github.com/softprops/action-gh-release/compare/v2...v3)
    
    ---
    updated-dependencies:
    - dependency-name: actions/checkout
      dependency-version: 6.0.2
      dependency-type: direct:production
      update-type: version-update:semver-patch
      dependency-group: all-actions
    - dependency-name: vmactions/freebsd-vm
      dependency-version: 1.4.5
      dependency-type: direct:production
      update-type: version-update:semver-minor
      dependency-group: all-actions
    - dependency-name: github/codeql-action
      dependency-version: 4.36.0
      dependency-type: direct:production
      update-type: version-update:semver-minor
      dependency-group: all-actions
    - dependency-name: softprops/action-gh-release
      dependency-version: '3'
      dependency-type: direct:production
      update-type: version-update:semver-major
      dependency-group: all-actions
    ...
    
    Signed-off-by: dependabot[bot] <support at github.com>
    Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 232969889..5f7a5e237 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -197,7 +197,7 @@ jobs:
         python3 -m pip install --disable-pip-version-check --user cmake==${{ matrix.ci.cmake }}
         echo "$(python3 -m site --user-base)/bin" >> $GITHUB_PATH
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -281,7 +281,7 @@ jobs:
         build_type: ['Debug', 'Release']
 
     steps:
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: 'Setup'
       uses: msys2/setup-msys2 at v2
@@ -337,7 +337,7 @@ jobs:
             arch: arm64
   
     steps:
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     # ccache not supported for this generator and/or Debug
 
@@ -378,7 +378,7 @@ jobs:
     runs-on: ${{ matrix.ci.os }}
     steps:
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -459,7 +459,7 @@ jobs:
         which clang++
         clang++ --version
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -495,7 +495,7 @@ jobs:
     name: FreeBSD
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -506,7 +506,7 @@ jobs:
         restore-keys: freebsd
 
     - name: Build and test
-      uses: vmactions/freebsd-vm at v1
+      uses: vmactions/freebsd-vm at v1.4.5
       with:
         release: "15.0"
         envs: CCACHE_COMPRESS CCACHE_COMPRESSLEVEL CCACHE_MAXSIZE
@@ -540,7 +540,7 @@ jobs:
         sudo -E apt-get autopurge -y needrestart
         sudo -E apt-get -yq --no-install-suggests --no-install-recommends install make cmake emscripten ccache
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Retrieve build cache
       uses: actions/cache/restore at v5
@@ -582,7 +582,7 @@ jobs:
         sudo -E apt-get -yq --no-install-suggests --no-install-recommends install cppcheck
         python3 -m pip install --disable-pip-version-check --user codespell
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: 'cppcheck'
       run: ./tools/cppcheck.sh
@@ -605,7 +605,7 @@ jobs:
         python3 -m pip install --disable-pip-version-check --user cmake==3.15.*
         echo "$(python3 -m site --user-base)/bin" >> $GITHUB_PATH
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
       with:
         path: geos
 
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 46eb081ac..39126ac0d 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -36,11 +36,11 @@ jobs:
         # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
 
     steps:
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init at v4
+      uses: github/codeql-action/init at v4.36.0
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -63,6 +63,6 @@ jobs:
           make -j$(nproc)
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze at v4
+      uses: github/codeql-action/analyze at v4.36.0
       with:
         category: "/language:${{matrix.language}}"
diff --git a/.github/workflows/container.yml b/.github/workflows/container.yml
index 42a93ec20..d9168c715 100644
--- a/.github/workflows/container.yml
+++ b/.github/workflows/container.yml
@@ -24,7 +24,7 @@ jobs:
 
     steps:
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Docker meta
       id: meta
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 2edbafad7..2920c83ae 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -32,7 +32,7 @@ jobs:
         uname -a
         sudo -E apt-get -yq --no-install-suggests --no-install-recommends install make doxygen
 
-    - uses: actions/checkout at v6
+    - uses: actions/checkout at v6.0.2
 
     - name: Get tag
       id: tag
@@ -67,7 +67,7 @@ jobs:
     - name: Create Release
       if: ${{ steps.tag.outputs.tag == steps.version.outputs.geosversion }}
       id: create_release
-      uses: softprops/action-gh-release at v2
+      uses: softprops/action-gh-release at v3
       with:
         body_path: ${{ steps.notes.outputs.geosnotes }}
         name: Release ${{ steps.version.outputs.geosversion }}
diff --git a/.github/workflows/web.yml b/.github/workflows/web.yml
index c059e4210..cdd46c346 100644
--- a/.github/workflows/web.yml
+++ b/.github/workflows/web.yml
@@ -27,7 +27,7 @@ jobs:
         sudo -E apt-get -yq --no-install-suggests --no-install-recommends install make doxygen
 
     - name: 'Check Out ?'
-      uses: actions/checkout at v6
+      uses: actions/checkout at v6.0.2
 
     - name: 'Hugo Build ?'
       # ...or replace 'master' with a full version tag, such as: v0.64.1

-----------------------------------------------------------------------

Summary of changes:
 .github/workflows/ci.yml        | 20 ++++++++++----------
 .github/workflows/codeql.yml    |  6 +++---
 .github/workflows/container.yml |  2 +-
 .github/workflows/release.yml   |  4 ++--
 .github/workflows/web.yml       |  2 +-
 5 files changed, 17 insertions(+), 17 deletions(-)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Fri Jun 12 10:49:29 2026
From: git at osgeo.org (git at osgeo.org)
Date: Fri, 12 Jun 2026 10:49:29 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 ac5da1cb2ed3e76cd286bb0f715e7fccde89281e
Message-ID: <20260612174929.86B501320EE@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, main has been updated
       via  ac5da1cb2ed3e76cd286bb0f715e7fccde89281e (commit)
      from  9d1676ca58c6878445b679d6b3228b96fab7d4e4 (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
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- Log -----------------------------------------------------------------
commit ac5da1cb2ed3e76cd286bb0f715e7fccde89281e
Author: Paul Ramsey <pramsey at cleverelephant.ca>
Date:   Fri Jun 12 17:46:41 2026 +0000

    Remove warning in MSVC build

diff --git a/include/geos/index/intervalrtree/IntervalRTreeNode.h b/include/geos/index/intervalrtree/IntervalRTreeNode.h
index d15d54a7e..457190d8c 100644
--- a/include/geos/index/intervalrtree/IntervalRTreeNode.h
+++ b/include/geos/index/intervalrtree/IntervalRTreeNode.h
@@ -15,6 +15,7 @@
 
 #pragma once
 
+#include <geos/export.h>
 #include <geos/constants.h>
 #include <vector>
 #include <limits>
@@ -31,7 +32,7 @@ namespace geos {
 namespace index {
 namespace intervalrtree {
 
-class IntervalRTreeNode {
+class GEOS_DLL IntervalRTreeNode {
 private:
 protected:
     double min;

-----------------------------------------------------------------------

Summary of changes:
 include/geos/index/intervalrtree/IntervalRTreeNode.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Tue Jun 16 11:27:15 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue, 16 Jun 2026 11:27:15 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 11f1851a82bdf5f9983f03d1b967adfb5da6fb39
Message-ID: <20260616182716.1419E1A1AFD@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
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The branch, main has been updated
       via  11f1851a82bdf5f9983f03d1b967adfb5da6fb39 (commit)
       via  47a2a8fba3190aa8604f2e2ef55e649cd67f3f7a (commit)
       via  420c2a988d54fc07e9ff8a513f7df1fdca7ad741 (commit)
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       via  fa14b9a717e2231679859d20adae502ebff07492 (commit)
      from  ac5da1cb2ed3e76cd286bb0f715e7fccde89281e (commit)

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- Log -----------------------------------------------------------------
commit 11f1851a82bdf5f9983f03d1b967adfb5da6fb39
Author: Daniel Baston <dbaston at gmail.com>
Date:   Mon Jun 8 08:49:21 2026 -0400

    Apply suggestions from @rouault

diff --git a/include/geos/operation/overlayng/Edge.h b/include/geos/operation/overlayng/Edge.h
index b88a44fe7..3ee964c5d 100644
--- a/include/geos/operation/overlayng/Edge.h
+++ b/include/geos/operation/overlayng/Edge.h
@@ -64,7 +64,7 @@ private:
     int bDepthDelta = 0;
     bool bIsHole = false;
     std::shared_ptr<const geom::CoordinateSequence> pts;
-    bool ptsCurved;
+    const bool ptsCurved;
 
     // Methods
 
diff --git a/src/operation/overlayng/OverlayEdgeRing.cpp b/src/operation/overlayng/OverlayEdgeRing.cpp
index 12f4c8e92..98db9f536 100644
--- a/src/operation/overlayng/OverlayEdgeRing.cpp
+++ b/src/operation/overlayng/OverlayEdgeRing.cpp
@@ -284,7 +284,7 @@ OverlayEdgeRing::isPointInOrOut(const OverlayEdgeRing& otherRing) const {
     struct PointTester : public geom::CoordinateFilter {
 
     public:
-        explicit PointTester(const OverlayEdgeRing* p_ring) : m_er(p_ring), m_result(false) {}
+        explicit PointTester(const OverlayEdgeRing* p_ring) : m_er(p_ring) {}
 
         void filter_ro(const CoordinateXY* pt) override {
             Location loc = m_er->locate(*pt);
@@ -311,7 +311,7 @@ OverlayEdgeRing::isPointInOrOut(const OverlayEdgeRing& otherRing) const {
     private:
         const OverlayEdgeRing* m_er;
         bool m_done{false};
-        bool m_result;
+        bool m_result{false};
     };
 
     PointTester tester(this);

commit 47a2a8fba3190aa8604f2e2ef55e649cd67f3f7a
Author: Daniel Baston <dbaston at gmail.com>
Date:   Sun Jun 7 14:42:06 2026 -0400

    CircularArcIntersector: exactly preserve endpoints in cocircular arc intersection

diff --git a/src/algorithm/CircularArcIntersector.cpp b/src/algorithm/CircularArcIntersector.cpp
index 8d3fabf58..5f82d3230 100644
--- a/src/algorithm/CircularArcIntersector.cpp
+++ b/src/algorithm/CircularArcIntersector.cpp
@@ -427,32 +427,34 @@ CircularArcIntersector::addCocircularIntersection(double startAngle, double endA
     CoordinateXYZM computedMidPt(CircularArcs::createPoint(center, radius, theta1));
     CoordinateXYZM computedEndPt(CircularArcs::createPoint(center, radius, endAngle));
 
-    if (precisionModel) {
-        precisionModel->makePrecise(computedStartPt);
-        precisionModel->makePrecise(computedMidPt);
-        precisionModel->makePrecise(computedEndPt);
-    }
-
     // Check to see if the endpoints of the intersection match the endpoints of either of
     // the input arcs. Use angles for the check to avoid missing an endpoint intersection from
     // inaccuracy in the point construction.
-    if (startAngle == arc1.theta0()) {
+    if (startAngle == Angle::normalizePositive(arc1.theta0())) {
+        computedStartPt = arc1.p0();
         setFromEndpoint(computedStartPt, arc1, 0);
-    } else if (startAngle == arc1.theta2()) {
+    } else if (startAngle == Angle::normalizePositive(arc1.theta2())) {
+        computedStartPt = arc1.p2();
         setFromEndpoint(computedStartPt, arc1, 2);
-    } else if (startAngle == arc2.theta0()) {
+    } else if (startAngle == Angle::normalizePositive(arc2.theta0())) {
+        computedStartPt = arc2.p0();
         setFromEndpoint(computedStartPt, arc2, 0);
-    } else if (startAngle == arc2.theta2()) {
+    } else if (startAngle == Angle::normalizePositive(arc2.theta2())) {
+        computedStartPt = arc2.p2();
         setFromEndpoint(computedStartPt, arc2, 2);
     }
 
-    if (endAngle == arc1.theta0()) {
+    if (endAngle == Angle::normalizePositive(arc1.theta0())) {
+        computedEndPt = arc1.p0();
         setFromEndpoint(computedEndPt, arc1, 0);
-    } else if (endAngle == arc1.theta2()) {
+    } else if (endAngle == Angle::normalizePositive(arc1.theta2())) {
+        computedEndPt = arc1.p2();
         setFromEndpoint(computedEndPt, arc1, 2);
-    } else if (endAngle == arc2.theta0()) {
+    } else if (endAngle == Angle::normalizePositive(arc2.theta0())) {
+        computedEndPt = arc2.p0();
         setFromEndpoint(computedEndPt, arc2, 0);
-    } else if (endAngle == arc2.theta2()) {
+    } else if (endAngle == Angle::normalizePositive(arc2.theta2())) {
+        computedEndPt = arc2.p2();
         setFromEndpoint(computedEndPt, arc2, 2);
     }
 
@@ -460,6 +462,12 @@ CircularArcIntersector::addCocircularIntersection(double startAngle, double endA
     interpolateZM(arc1, arc2, computedMidPt);
     interpolateZM(arc1, arc2, computedEndPt);
 
+    if (precisionModel) {
+        precisionModel->makePrecise(computedStartPt);
+        precisionModel->makePrecise(computedMidPt);
+        precisionModel->makePrecise(computedEndPt);
+    }
+
     auto seq = std::make_unique<CoordinateSequence>(3, constructZ, constructM);
     seq->setAt(computedStartPt, 0);
     seq->setAt(computedMidPt, 1);
diff --git a/tests/unit/algorithm/CircularArcIntersectorTest.cpp b/tests/unit/algorithm/CircularArcIntersectorTest.cpp
index e9899213d..5d0123c17 100644
--- a/tests/unit/algorithm/CircularArcIntersectorTest.cpp
+++ b/tests/unit/algorithm/CircularArcIntersectorTest.cpp
@@ -1733,6 +1733,26 @@ void object::test<86>()
 }
 
 
+template<>
+template<>
+void object::test<87>()
+{
+    set_test_name("arc intersected with itself yields arc with identical endpoints");
+
+    CircularArcIntersector cai;
+
+    auto arc = CircularArc::create(XY{0, 0}, XY{2, 0}, XY{2, 1});
+
+    cai.intersects(arc, arc);
+
+    ensure_equals(cai.getNumArcs(), 1u);
+
+    const CircularArc& arcOut = cai.getArc(0);
+
+    ensure_equals(arc.p0(), arcOut.p0());
+    ensure_equals(arc.p2(), arcOut.p2());
+}
+
 // TODO: check Z values of arc result centerpoints
 // TODO: add tests for seg/seg
 

commit 420c2a988d54fc07e9ff8a513f7df1fdca7ad741
Author: Daniel Baston <dbaston at gmail.com>
Date:   Mon Jun 8 08:35:41 2026 -0400

    NodableArcString: properly handle splits at arc endpoints

diff --git a/src/noding/NodableArcString.cpp b/src/noding/NodableArcString.cpp
index 4b824b3fa..d05865e79 100644
--- a/src/noding/NodableArcString.cpp
+++ b/src/noding/NodableArcString.cpp
@@ -21,6 +21,8 @@
 using geos::geom::CoordinateXYZM;
 using geos::geom::CircularArc;
 
+#define DEBUG_NODABLE_ARC_STRING 0
+
 namespace geos::noding {
 
 static double
@@ -41,12 +43,22 @@ NodableArcString::NodableArcString(std::vector<geom::CircularArc> arcs, const st
 {
 }
 
-static
-std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector<CoordinateXYZM> splitPoints)
+struct SplitPoints {
+
+    std::vector<CoordinateXYZM> points{};
+    bool splitStart{false};
+    bool splitEnd{false};
+};
+
+static SplitPoints
+prepareArcPoints(const CircularArc& arc, std::vector<CoordinateXYZM> splitPoints)
 {
     const bool isCCW = arc.getOrientation() == algorithm::Orientation::COUNTERCLOCKWISE;
     const geom::CoordinateXY& center = arc.getCenter();
 
+    bool splitStart = false;
+    bool splitEnd = false;
+
     // Some potential split points may be skipped, for example, if they would create an arc section that is
     // too short to have a constructed midpoint. Because the results of this logic could depend on the
     // direction in which the arc is processed, we reverse clockwise arcs and then reverse the list of
@@ -65,7 +77,17 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
         double pa0 = geom::Quadrant::pseudoAngle(center, p0);
         double pa1 = geom::Quadrant::pseudoAngle(center, p1);
 
-        return pseudoAngleDiffCCW(paStart, pa0) < pseudoAngleDiffCCW(paStart, pa1);
+        double diff0 = pseudoAngleDiffCCW(paStart, pa0);
+        double diff1 = pseudoAngleDiffCCW(paStart, pa1);
+
+        if (diff0 < diff1) {
+            return true;
+        }
+        if (diff0 > diff1) {
+            return false;
+        }
+
+        return p0 < p1;
     });
 
     // Add ending point of input arc
@@ -75,20 +97,50 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
         splitPoints.push_back(p2);
     }
 
+#if DEBUG_NODABLE_ARC_STRING
+    std::cout << std::setprecision(17);
+    std::cout << std::endl;
+    std::cout << "Edge from " << arc.p0() << " to " << arc.p2() << " has " << splitPoints.size() << " potential split points:" << std::endl;
+    std::cout << "Edge is CIRCULARSTRING " << *arc.getCoordinateSequence() << std::endl;
+    std::cout << "Start point is " << retained.back() << " pa " << paStart << std::endl;
+    std::cout << "Potential split points:" << std::endl;
+    for (std::size_t i = 0; i < splitPoints.size(); i++) {
+        std::cout << "  " << splitPoints[i] << " paDiff " << pseudoAngleDiffCCW(paStart, geom::Quadrant::pseudoAngle(center, splitPoints[i]));
+        if (i > 0) {
+            std::cout << "     " << splitPoints[i].distance(splitPoints[i-1]);
+        }
+        std::cout << std::endl;
+    }
+#endif
+
     for (const auto& p2 : splitPoints) {
         auto& p0 = retained.back();
 
+#if DEBUG_NODABLE_ARC_STRING
+        std::cout << "p0 = " << p0 << std::endl;
+#endif
+
         if (p2.equals2D(p0)) {
+#if DEBUG_NODABLE_ARC_STRING
+            std::cout << "Split point " << p2 << " equal to start point " << p0 << std::endl;
+#endif
             if (std::isnan(p0.z) && !std::isnan(p2.z)) {
                 p0.z = p2.z;
             }
             if (std::isnan(p0.m) && !std::isnan(p2.m)) {
                 p0.m = p2.m;
             }
+
+            if (retained.size() == 1) {
+                splitStart = true;
+            }
             continue;
         }
 
         if (!arc.containsPointOnCircle(p2)) {
+#if DEBUG_NODABLE_ARC_STRING
+            std::cout << "Skipping split point " << p2 << " because it is outside of the arc" << std::endl;
+#endif
             continue;
         }
 
@@ -98,6 +150,22 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
         const geom::CoordinateXY p1 = algorithm::CircularArcs::getMidpoint(p0, p2, center, arc.getRadius(), true);
 
         if (p1.equals2D(p0) || p1.equals2D(p2)) {
+#if DEBUG_NODABLE_ARC_STRING
+            std::cout << "Skipping split point " << p2 << " because the calculated arc midpoint " << p1 << " equals one of the endpoints" << std::endl;
+#endif
+            if (retained.size() == 1) {
+                splitStart = true;
+            }
+            continue;
+        }
+
+        if (algorithm::Orientation::index(p1, p0, p2) == algorithm::Orientation::COLLINEAR) {
+#if DEBUG_NODABLE_ARC_STRING
+            std::cout << "Skipping split point " << p2 << " because the calculated arc midpoint " << p1 << " is collinear with the endpoints" << std::endl;
+#endif
+            if (retained.size() == 1) {
+                splitStart = true;
+            }
             continue;
         }
 
@@ -106,10 +174,19 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
         const double t1 = algorithm::Angle::normalizePositive(algorithm::CircularArcs::getAngle(p1, center));
         const double t2 = algorithm::Angle::normalizePositive(isCCW ? arc.theta2() : arc.theta0());
 
-        if (!algorithm::Angle::isWithinCCW(t1, t0, t2)) {
+        if (!algorithm::Angle::isWithinCCW(t1, t0, t2)) { // != isCCW) {
+#if DEBUG_NODABLE_ARC_STRING
+            std::cout << "Skipping split point " << p2 << " because the calculated arc midpoint " << p1 << " does not fall within the arc from " << p0 << " to " << p2 << std::endl;
+#endif
+            if (retained.size() == 1) {
+                splitStart = true;
+            }
             continue;
         }
 
+#if DEBUG_NODABLE_ARC_STRING
+        std::cout << "Keeping split point " << p2 << std::endl;
+#endif
         retained.push_back(p2);
     }
 
@@ -120,6 +197,7 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
         CoordinateXYZM& back = retained.back();
 
         if (!back.equals2D(p2)) {
+            splitEnd = true;
             back.x = p2.x;
             back.y = p2.y;
         }
@@ -133,15 +211,75 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
 
     if (!isCCW) {
         std::reverse(retained.begin(), retained.end());
+        std::swap(splitStart, splitEnd);
     }
 
-    return retained;
+#if DEBUG_NODABLE_ARC_STRING
+    std::cout << "Retained split points:" << std::endl;
+    for (std::size_t i = 0; i < retained.size(); i++) {
+        std::cout << "  " << retained[i] << " paDiff " << pseudoAngleDiffCCW(paStart, geom::Quadrant::pseudoAngle(center, retained[i]));
+        if (i > 0) {
+            std::cout << "     " << retained[i].distance(retained[i-1]);
+        }
+        std::cout << std::endl;
+    }
+#endif
+
+    return SplitPoints{std::move(retained), splitStart, splitEnd};
 }
 
+class ArcBuilder {
+
+public:
+
+    ArcBuilder(std::vector<std::unique_ptr<ArcString>>& splitArcs, const void* data, bool constructZ, bool constructM) :
+        m_data(data),
+        m_splitArcs(splitArcs),
+        m_constructZ(constructZ),
+        m_constructM(constructM) {}
+
+    void addArc(const CoordinateXYZM& p0, const CoordinateXYZM& p1, const CoordinateXYZM& p2, const geom::CoordinateXY& center, double radius, int orientation) {
+        if (!m_coords) {
+            m_coords = std::make_unique<geom::CoordinateSequence>(0, m_constructZ, m_constructM);
+        }
+
+        m_coords->add(p0, false);
+        m_coords->add(p1, false);
+        m_coords->add(p2, false);
+
+        m_arcs.emplace_back(*m_coords, m_coords->getSize() - 3, center, radius, orientation);
+    }
+
+    void addArc(const geom::CoordinateSequence& seq, std::size_t pos, const geom::CoordinateXY& center, double radius, int orientation) {
+        if (!m_coords) {
+            m_coords = std::make_unique<geom::CoordinateSequence>(0, m_constructZ, m_constructM);
+        }
+
+        m_coords->add(seq, pos, pos + 2, false);
+        m_arcs.emplace_back(*m_coords, m_coords->getSize() - 3, center, radius, orientation);
+    }
+
+    void finish() {
+        if (m_arcs.empty()) {
+            return;
+        }
+
+        m_splitArcs.push_back(std::make_unique<NodableArcString>(std::move(m_arcs), std::move(m_coords), m_constructZ, m_constructM, m_data));
+        m_arcs = std::vector<CircularArc>();
+    }
+
+private:
+    const void* m_data;
+    std::vector<std::unique_ptr<ArcString>>& m_splitArcs;
+    std::vector<CircularArc> m_arcs;
+    std::unique_ptr<geom::CoordinateSequence> m_coords;
+    const bool m_constructZ;
+    const bool m_constructM;
+};
+
 void
 NodableArcString::getNoded(std::vector<std::unique_ptr<ArcString>>& splitArcs) {
-    auto dstSeq = std::make_unique<geom::CoordinateSequence>(0, m_constructZ, m_constructM);
-    std::vector<geom::CircularArc> arcs;
+    ArcBuilder builder(splitArcs, getData(), m_constructZ, m_constructM);
 
     for (size_t arcIndex = 0; arcIndex < m_arcs.size(); arcIndex++) {
         const CircularArc& toSplit = m_arcs[arcIndex];
@@ -149,36 +287,28 @@ NodableArcString::getNoded(std::vector<std::unique_ptr<ArcString>>& splitArcs) {
         const double radius = toSplit.getRadius();
         const int orientation = toSplit.getOrientation();
 
-        bool arcIsSplit = true;
-        bool createArcString = true;
-        const bool preserveControlPoint = true;
-        std::vector<CoordinateXYZM> arcPoints;
-        const auto it = m_adds.find(arcIndex);
-        if (it == m_adds.end()) {
-            arcIsSplit = false;
-            createArcString = false;
-        } else {
-            arcPoints = prepareArcPoints(toSplit, it->second);
+        SplitPoints split;
 
-            if (arcPoints.size() == 2) {
-                // All added nodes collapsed
-                // Still need to know if arc was split.
-                arcIsSplit = false;
-            }
+        const bool preserveControlPoint = true;
+
+        const auto it = m_adds.find(arcIndex);
+        if (it != m_adds.end()) {
+            split = prepareArcPoints(toSplit, it->second);
         }
 
-        if (preserveControlPoint && !arcIsSplit) {
+        if (split.splitStart) {
+            builder.finish();
+        }
+
+        if (preserveControlPoint && split.points.size() <= 2) {
             // No nodes added, just copy the coordinates into the sequence.
             const geom::CoordinateSequence* srcSeq = m_arcs[arcIndex].getCoordinateSequence();
             std::size_t srcPos = m_arcs[arcIndex].getCoordinatePosition();
-            dstSeq->add(*srcSeq, srcPos, srcPos + 2, false);
-            std::size_t dstPos = dstSeq->getSize() - 3;
-            arcs.emplace_back(*dstSeq, dstPos, center, radius, orientation);
 
-            if (createArcString) {
-                splitArcs.push_back(std::make_unique<NodableArcString>(std::move(arcs), std::move(dstSeq), m_constructZ, m_constructM, getData()));
-                dstSeq = std::make_unique<geom::CoordinateSequence>(0, m_constructZ, m_constructM);
-                arcs.clear();
+            builder.addArc(*srcSeq, srcPos, center, radius, orientation);
+
+            if (split.splitEnd) {
+                builder.finish();
             }
 
             continue;
@@ -186,9 +316,9 @@ NodableArcString::getNoded(std::vector<std::unique_ptr<ArcString>>& splitArcs) {
 
         const bool isCCW = orientation == algorithm::Orientation::COUNTERCLOCKWISE;
 
-        for (std::size_t i = 1; i < arcPoints.size(); i++) {
-            const CoordinateXYZM& p0 = arcPoints[i - 1];
-            const CoordinateXYZM& p2 = arcPoints[i];
+        for (std::size_t i = 1; i < split.points.size(); i++) {
+            const CoordinateXYZM& p0 = split.points[i - 1];
+            const CoordinateXYZM& p2 = split.points[i];
 
             // TODO: Check if control point of original arc falls into this section,
             // and use it instead of calculating a midpoint here?
@@ -196,28 +326,18 @@ NodableArcString::getNoded(std::vector<std::unique_ptr<ArcString>>& splitArcs) {
             p1.z = (p0.z + p2.z) / 2;
             p1.m = (p0.m + p2.m) / 2;
 
-            if (dstSeq->isEmpty()) {
-                dstSeq->add(p0);
-            }
-            dstSeq->add(p1);
-            dstSeq->add(p2);
-
-            const std::size_t dstPos = dstSeq->getSize() - 3;
-            arcs.emplace_back(*dstSeq, dstPos, center, radius, orientation);
+            builder.addArc(p0, p1, p2, center, radius, orientation);
 
             // Finish the ArcString, start a new one.
-            const bool isSplitPoint = i != arcPoints.size() - 1;
+            const bool isSplitPoint = (i < split.points.size() - 1) || split.splitEnd;
             if (isSplitPoint) {
-                splitArcs.push_back(std::make_unique<NodableArcString>(std::move(arcs), std::move(dstSeq), m_constructZ, m_constructM, getData()));
-                dstSeq = std::make_unique<geom::CoordinateSequence>(0, m_constructZ, m_constructM);
-                arcs.clear();
+                builder.finish();
+
             }
         }
     }
 
-    if (!arcs.empty()) {
-        splitArcs.push_back(std::make_unique<NodableArcString>(std::move(arcs), std::move(dstSeq), m_constructZ, m_constructM, getData()));
-    }
+    builder.finish();
 }
 
 }
\ No newline at end of file
diff --git a/tests/unit/operation/overlayng/OverlayNGTest.cpp b/tests/unit/operation/overlayng/OverlayNGTest.cpp
index 46b8155fa..2da3cbcca 100644
--- a/tests/unit/operation/overlayng/OverlayNGTest.cpp
+++ b/tests/unit/operation/overlayng/OverlayNGTest.cpp
@@ -6,9 +6,6 @@
 
 // geos
 #include <geos/operation/overlayng/OverlayNG.h>
-#include <geos/noding/SimpleNoder.h>
-#include <geos/algorithm/CircularArcIntersector.h>
-#include <geos/noding/ArcIntersectionAdder.h>
 
 // std
 #include <memory>
@@ -818,4 +815,32 @@ void object::test<62>()
     testOverlay(a, a, exp, OverlayNG::UNION, 0);
 }
 
+template<>
+template<>
+void object::test<63>()
+{
+    set_test_name("Union of CurvePolygon / CurvePolygon -> CurvePolygon");
+
+    std::string a = "CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (-1.1087328289561522 -0.2365594619955851, -1.2116499629412223 -0.2219284209572556, -1.3064159292035398 -0.1792035398230087), (-1.3064159292035398 -0.1792035398230087, -1.2982128297312812 -0.0461310372730352), CIRCULARSTRING (-1.2982128297312812 -0.0461310372730352, -1.2213760168089367 -0.1591592707276735, -1.1087328289561522 -0.2365594619955851)))";
+    std::string b = "CURVEPOLYGON (COMPOUNDCURVE ((-1.277492733105557 0.2899949746553787,  -0.8433316896087282 -0.1241204385865409), CIRCULARSTRING (-0.8433316896087282 -0.1241204385865409, -0.9646131918909476 -0.2072935239179199, -1.1087328289561522 -0.2365594619955851, -1.2213760168089367 -0.1591592707276735, -1.2982128297312812 -0.0461310372730352), (-1.2982128297312812 -0.0461310372730352, -1.277492733105557 0.2899949746553787)))";
+
+    std::string exp = "CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (-1.1087328289561522 -0.2365594619955851, -1.2116499629412223 -0.2219284209572556, -1.3064159292035398 -0.1792035398230087), (-1.3064159292035398 -0.1792035398230087, -1.2982128297312812 -0.0461310372730352, -1.277492733105557 0.2899949746553787, -0.8433316896087282 -0.1241204385865409), CIRCULARSTRING (-0.8433316896087282 -0.1241204385865409, -0.9646131918909476 -0.2072935239179199, -1.1087328289561522 -0.2365594619955851)))";
+
+    testOverlay(a, b, exp, OverlayNG::UNION, 0);
+}
+
+template<>
+template<>
+void object::test<64>()
+{
+    set_test_name("Union of CurvePolygon / CurvePolygon -> CurvePolygon (2)");
+
+    std::string a = "MULTISURFACE (CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (-1.266592920353982 0.4668141592920354, -1.1143440097781072 0.502208020974126, -0.9610873502585282 0.4714695673823874, -1.1432212469102676 0.4224569115784076, -1.277492733105557 0.2899949746553787), (-1.277492733105557 0.2899949746553787, -1.266592920353982 0.4668141592920354))), CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (-0.7885401828539679 0.3170953789649493, -0.7421261955995471 0.0873215546859087, -0.8433316896087282 -0.1241204385865409), (-0.8433316896087282 -0.1241204385865409, -0.7885401828539679 0.3170953789649493))), CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (-1.1087328289561522 -0.2365594619955851, -1.2116499629412223 -0.2219284209572556, -1.3064159292035398 -0.1792035398230087), (-1.3064159292035398 -0.1792035398230087, -1.2982128297312812 -0.0461310372730352), CIRCULARSTRING (-1.2982128297312812 -0.0461310372730352, -1.2213760168089367 -0.1591592707276735, -1.1087328289561522 -0.23655946199
 55851))))";
+    std::string b = "CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (-0.9610873502585282 0.4714695673823874, -0.8624070192245114 0.4081497467816552, -0.7885401828539679 0.3170953789649493), (-0.7885401828539679 0.3170953789649493, -0.8433316896087282 -0.1241204385865409), CIRCULARSTRING (-0.8433316896087282 -0.1241204385865409, -0.9646131918909476 -0.2072935239179199, -1.1087328289561522 -0.2365594619955851, -1.2213760168089367 -0.1591592707276735, -1.2982128297312812 -0.0461310372730352), (-1.2982128297312812 -0.0461310372730352, -1.277492733105557 0.2899949746553787), CIRCULARSTRING (-1.277492733105557 0.2899949746553787, -1.1432212469102676 0.4224569115784076, -0.9610873502585282 0.4714695673823874)))";
+
+    std::string exp = "CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (-1.266592920353982 0.4668141592920354, -1.1143440097781072 0.502208020974126, -0.9610873502585282 0.4714695673823874, -0.8624070192245114 0.4081497467816552, -0.7885401828539679 0.3170953789649493, -0.7421261955995471 0.0873215546859087, -0.8433316896087282 -0.1241204385865409, -0.9646131918909476 -0.2072935239179199, -1.1087328289561522 -0.2365594619955851, -1.2116499629412223 -0.2219284209572556, -1.3064159292035398 -0.1792035398230087), (-1.3064159292035398 -0.1792035398230087, -1.2982128297312812 -0.0461310372730352, -1.277492733105557 0.2899949746553787, -1.266592920353982 0.4668141592920354)))";
+
+    testOverlay(a, b, exp, OverlayNG::UNION, 0);
+}
+
 } // namespace tut

commit 3da292784f83e0bfce769442d4d7e14cdc964bc6
Author: Daniel Baston <dbaston at gmail.com>
Date:   Sun Jun 7 12:03:15 2026 -0400

    CircularArcIntersector: improve robustness of arc/arc endpoint intersection

diff --git a/src/algorithm/CircularArcIntersector.cpp b/src/algorithm/CircularArcIntersector.cpp
index ad79ee190..8d3fabf58 100644
--- a/src/algorithm/CircularArcIntersector.cpp
+++ b/src/algorithm/CircularArcIntersector.cpp
@@ -235,55 +235,39 @@ CircularArcIntersector::intersects(const CircularArc& arc1, const CircularArc& a
     if (a == 0 || (d == 0 && r1 == r2)) {
         computeCocircularIntersection(arc1, arc2);
     } else {
-        // Explicitly add endpoint intersections that may be missed or inexactly computed.
-        if (arc1.p0().equals2D(arc2.p0()) && !hasIntersection(arc1.p0())) {
-            addArcArcIntersectionPoint(arc1.p0(), arc1, arc2);
+        // Compute interior intersection points.
+        const double dx = c2.x-c1.x;
+        const double dy = c2.y-c1.y;
+
+        // point where a line between the two circle center points intersects
+        // the radical line
+        CoordinateXY p{c1.x + a* dx/d, c1.y+a* dy/d};
+
+        // distance from p to the intersection points
+        const double h = std::sqrt(r1*r1 - a*a);
+
+        CoordinateXY isect0{p.x + h* dy/d, p.y - h* dx/d };
+        CoordinateXY isect1{p.x - h* dy/d, p.y + h* dx/d };
+
+        // Check to see if computed intersection points are inexact versions of an endpoint intersection
+        const CoordinateXY& ap0 = arc1.p0();
+        const CoordinateXY& ap2 = arc1.p2();
+        const CoordinateXY& bp0 = arc2.p0();
+        const CoordinateXY& bp2 = arc2.p2();
+
+        if (ap0 == bp0 || ap0 == bp2) {
+            closestPoint(isect0, isect1, 2, ap0) = ap0;
         }
-        if (arc1.p0().equals2D(arc2.p2()) && !hasIntersection(arc1.p0())) {
-            addArcArcIntersectionPoint(arc1.p0(), arc1, arc2);
-        }
-        if (arc1.p2().equals2D(arc2.p0()) && !hasIntersection(arc1.p2())) {
-            addArcArcIntersectionPoint(arc1.p2(), arc1, arc2);
-        }
-        if (arc1.p2().equals2D(arc2.p2()) && !hasIntersection(arc1.p2())) {
-            addArcArcIntersectionPoint(arc1.p2(), arc1, arc2);
+        if (ap2 == bp0 || ap2 == bp2) {
+            closestPoint(isect0, isect1, 2, ap2) = ap2;
         }
 
-        if (nPt < 2) {
-            // Compute interior intersection points.
-            const double dx = c2.x-c1.x;
-            const double dy = c2.y-c1.y;
+        if (arc1.containsPointOnCircle(isect0) && arc2.containsPointOnCircle(isect0)) {
+            addArcArcIntersectionPoint(isect0, arc1, arc2);
+        }
 
-            // point where a line between the two circle center points intersects
-            // the radical line
-            CoordinateXY p{c1.x + a* dx/d, c1.y+a* dy/d};
-
-            // distance from p to the intersection points
-            const double h = std::sqrt(r1*r1 - a*a);
-
-            CoordinateXY isect0{p.x + h* dy/d, p.y - h* dx/d };
-            CoordinateXY isect1{p.x - h* dy/d, p.y + h* dx/d };
-
-            // One of the computed intersection points may be an inexact version of an endpoint.
-            // If we already have an endpoint intersection, we need to process the farther-away
-            // computed point first.
-            if (nPt == 1 && intPt[0].distance(isect0) < intPt[0].distance(isect1)) {
-                std::swap(isect0, isect1);
-            }
-
-            for (const CoordinateXY& computedIntPt : {isect0, isect1}) {
-                if (nPt > 0 && computedIntPt.equals2D(intPt[0])) {
-                    continue;
-                }
-
-                if (nPt > 1) {
-                    continue;
-                }
-
-                if (arc1.containsPointOnCircle(computedIntPt) && arc2.containsPointOnCircle(computedIntPt)) {
-                    addArcArcIntersectionPoint(computedIntPt, arc1, arc2);
-                }
-            }
+        if (isect1 != isect0 && arc1.containsPointOnCircle(isect1) && arc2.containsPointOnCircle(isect1)) {
+            addArcArcIntersectionPoint(isect1, arc1, arc2);
         }
     }
 

commit f0ffac4dc49d012f3d80cb28f76e9ff10d79772f
Author: Daniel Baston <dbaston at gmail.com>
Date:   Sun Jun 7 11:50:32 2026 -0400

    CircularArc: Add getReverseDirectionPoint

diff --git a/include/geos/geom/CircularArc.h b/include/geos/geom/CircularArc.h
index 9f9bbc693..800eb0144 100644
--- a/include/geos/geom/CircularArc.h
+++ b/include/geos/geom/CircularArc.h
@@ -110,6 +110,8 @@ public:
     /// line tangent to the arc at the origin point.
     CoordinateXY getDirectionPoint() const;
 
+    CoordinateXY getReverseDirectionPoint() const;
+
     Envelope getEnvelope() const;
 
     /// Return the length of the arc
diff --git a/src/geom/CircularArc.cpp b/src/geom/CircularArc.cpp
index fa772b69b..ed622c135 100644
--- a/src/geom/CircularArc.cpp
+++ b/src/geom/CircularArc.cpp
@@ -317,6 +317,16 @@ CircularArc::getDirectionPoint() const
     return CircularArcs::getDirectionPoint(getCenter(), getRadius(), theta0(), getOrientation() == algorithm::Orientation::COUNTERCLOCKWISE);
 }
 
+CoordinateXY
+CircularArc::getReverseDirectionPoint() const
+{
+    if (isLinear()) {
+        return p0();
+    }
+
+    return CircularArcs::getDirectionPoint(getCenter(), getRadius(), theta2(), getOrientation() != algorithm::Orientation::COUNTERCLOCKWISE);
+}
+
 Envelope
 CircularArc::getEnvelope() const
 {
diff --git a/src/operation/overlayng/OverlayUtil.cpp b/src/operation/overlayng/OverlayUtil.cpp
index 077ca2efb..275ca422f 100644
--- a/src/operation/overlayng/OverlayUtil.cpp
+++ b/src/operation/overlayng/OverlayUtil.cpp
@@ -348,7 +348,7 @@ OverlayUtil::getDirectionPoint(const CoordinateSequence& pts, bool forward, bool
             return arc.getDirectionPoint();
         } else {
             CircularArc arc(pts, pts.size() - 3);
-            return algorithm::CircularArcs::getDirectionPoint(arc.getCenter(), arc.getRadius(), arc.theta2(), !arc.isCCW());
+            return arc.getReverseDirectionPoint();
         }
     }
 

commit fac5376f75356ad9cd8b6f08ef0336f1d56e006c
Author: Daniel Baston <dbaston at gmail.com>
Date:   Mon Jun 8 08:35:59 2026 -0400

    CircularArc: handle direction point of degenerate arcs

diff --git a/src/geom/CircularArc.cpp b/src/geom/CircularArc.cpp
index dd5a56d85..fa772b69b 100644
--- a/src/geom/CircularArc.cpp
+++ b/src/geom/CircularArc.cpp
@@ -310,6 +310,10 @@ CircularArc::getArea() const {
 CoordinateXY
 CircularArc::getDirectionPoint() const
 {
+    if (isLinear()) {
+        return p2();
+    }
+
     return CircularArcs::getDirectionPoint(getCenter(), getRadius(), theta0(), getOrientation() == algorithm::Orientation::COUNTERCLOCKWISE);
 }
 

commit c06102e28158cd1393a68c767f36087b249e4ee0
Author: Daniel Baston <dbaston at gmail.com>
Date:   Sun Jun 7 11:47:50 2026 -0400

    CircularArcIntersector: Improve robustness of arc/segment endpoint intersection

diff --git a/include/geos/algorithm/CircularArcs.h b/include/geos/algorithm/CircularArcs.h
index a32a197cb..0aa868e23 100644
--- a/include/geos/algorithm/CircularArcs.h
+++ b/include/geos/algorithm/CircularArcs.h
@@ -65,6 +65,21 @@ public:
     static void interpolateZM(const geom::CoordinateSequence &seq, size_t i0, const geom::CoordinateXY &center, bool isCCW, geom::CoordinateXY &pt, double
                               &z, double &m);
 
+    /** Determines whether and where a circle intersects a line.
+     *
+     * @param center The center point of the circle
+     * @param r The radius of the circle
+     * @param p0 One point defining a line of infinite length
+     * @param p1 Second point defining a line of infinite length
+     * @param isect0 Set to the first intersection point, if it exists
+     * @param isect1 Set to the second intersection point, if it exists
+     * @return The number of intersection points
+     */
+    static int
+    circleIntersectsLine(const geom::CoordinateXY& center, double r,
+                         const geom::CoordinateXY& p0, const geom::CoordinateXY& p1,
+                         geom::CoordinateXY& isect0, geom::CoordinateXY& isect1);
+
     /** Determines whether and where a circle intersects a line segment.
      *
      * @param center The center point of the circle
diff --git a/src/algorithm/CircularArcIntersector.cpp b/src/algorithm/CircularArcIntersector.cpp
index c63cd2c55..ad79ee190 100644
--- a/src/algorithm/CircularArcIntersector.cpp
+++ b/src/algorithm/CircularArcIntersector.cpp
@@ -101,6 +101,23 @@ CircularArcIntersector::hasIntersection(const geom::CoordinateXY &p) const {
     return false;
 }
 
+static CoordinateXY&
+closestPoint(CoordinateXY& p0, CoordinateXY& p1, int n, const CoordinateXY& q)
+{
+    if (n < 2) {
+        return p0;
+    }
+
+    const double d0 = p0.distance(q);
+    const double d1 = p1.distance(q);
+
+    if (d0 < d1) {
+        return p0;
+    }
+
+    return p1;
+}
+
 void
 CircularArcIntersector::intersects(const CircularArc& arc, const CoordinateSequence& seq, std::size_t segPos0, std::size_t segPos1, bool useSegEndpoints)
 {
@@ -117,14 +134,35 @@ CircularArcIntersector::intersects(const CircularArc& arc, const CoordinateSeque
     const CoordinateXY& c = arc.getCenter();
     const double r = arc.getRadius();
 
-    CoordinateXYZM isect0, isect1;
-    auto n = CircularArcs::circleIntersectsSegment(c, r, seq.getAt<CoordinateXY>(segPos0), seq.getAt<CoordinateXY>(segPos1), isect0, isect1);
+    CoordinateXY isect0, isect1;
+    const auto nPointsIntersectingLine = CircularArcs::circleIntersectsLine(c, r, seq.getAt<CoordinateXY>(segPos0), seq.getAt<CoordinateXY>(segPos1), isect0, isect1);
 
-    if (n > 0 && arc.containsPointOnCircle(isect0)) {
+    if (nPointsIntersectingLine == 0) {
+        result = NO_INTERSECTION;
+        return;
+    }
+
+    // Check for exact endpoint-endpoint intersections
+    // If found, replace the computed intersection points with an exact endpoint
+    const CoordinateXY& ap0 = arc.p0<CoordinateXY>();
+    const CoordinateXY& ap2 = arc.p2<CoordinateXY>();
+    const CoordinateXY& bp0 = seq.getAt<CoordinateXY>(segPos0);
+    const CoordinateXY& bp1 = seq.getAt<CoordinateXY>(segPos1);
+
+    if (ap0 == bp0 || ap0 == bp1) {
+        closestPoint(isect0, isect1, nPointsIntersectingLine, ap0) = ap0;
+    }
+    if (ap2 == bp0 || ap2 == bp1) {
+        closestPoint(isect0, isect1, nPointsIntersectingLine, ap2) = ap2;
+    }
+
+    Envelope segEnv(bp0, bp1);
+
+    if (nPointsIntersectingLine > 0 && segEnv.contains(isect0) && arc.containsPointOnCircle(isect0)) {
         addArcSegmentIntersectionPoint(isect0, arc, seq, segPos0, segPos1, useSegEndpoints);
     }
 
-    if (n > 1  && arc.containsPointOnCircle(isect1)) {
+    if (nPointsIntersectingLine > 1 && segEnv.contains(isect1) && arc.containsPointOnCircle(isect1)) {
         addArcSegmentIntersectionPoint(isect1, arc, seq, segPos0, segPos1, useSegEndpoints);
     }
 
diff --git a/src/algorithm/CircularArcs.cpp b/src/algorithm/CircularArcs.cpp
index eeb779e2b..07f2bd630 100644
--- a/src/algorithm/CircularArcs.cpp
+++ b/src/algorithm/CircularArcs.cpp
@@ -309,22 +309,26 @@ CircularArcs::expandEnvelope(geom::Envelope& e, const geom::CoordinateXY& p0, co
 }
 
 int
-CircularArcs::circleIntersectsSegment(const CoordinateXY& center, double r,
-                                      const CoordinateXY& p0, const CoordinateXY& p1,
-                                      CoordinateXY& ret0, CoordinateXY& ret1)
+CircularArcs::circleIntersectsLine(const geom::CoordinateXY& center, double r,
+                        const geom::CoordinateXY& p0, const geom::CoordinateXY& p1,
+                        geom::CoordinateXY& isect0, geom::CoordinateXY& isect1)
 {
     const double& x0 = center.x;
     const double& y0 = center.y;
 
-    Envelope segEnv(p0, p1);
-
-    CoordinateXY isect0, isect1;
-    int n = 0;
-
     if (p1.x == p0.x) {
         // vertical line
         double x = p1.x;
 
+        if (p1.x > x0 + r || p1.x < x0 - r) {
+            return 0;
+        }
+
+        if (p1.x == x0 + r || p1.x == x0 - r) {
+            isect0 = {p1.x, y0};
+            return 1;
+        }
+
         double A = 1;
         double B = -2*y0;
         double C = x*x - 2*x*x0 + x0*x0 + y0*y0 - r*r;
@@ -335,41 +339,73 @@ CircularArcs::circleIntersectsSegment(const CoordinateXY& center, double r,
 
         isect0 = {x, Y1};
         isect1 = {x, Y2};
+
+        return 2;
     }
-    else {
-        double m = (p1.y - p0.y) / (p1.x - p0.x);
-        double b = p1.y - p1.x*m;
 
-        // Ax^2 + Bx + C = 0
-        double A = 1 + m*m;
-        double B = -2*x0 + 2*m*b - 2*m*y0;
-        double C = x0*x0 + b*b - 2*b*y0 + y0*y0 - r*r;
+    const double m = (p1.y - p0.y) / (p1.x - p0.x);
+    const double b = p1.y - p1.x*m;
 
-        double d = std::sqrt(B*B - 4*A*C);
-        double X1 = (-B + d)/(2*A);
-        double X2 = (-B - d)/(2*A);
+    // Take equation defining circle: (x - x0)^2 + (y - y0)^2 = r^2
+    // Substitute in equation defining line: y = mx + b
+    // Rearrange into standard quadratic form:  Ax^2 + Bx + C = 0
+    const double A = 1 + m*m;
+    const double B = -2*x0 + 2*m*b - 2*m*y0;
+    const double C = x0*x0 + b*b - 2*b*y0 + y0*y0 - r*r;
 
-        // TODO use robust quadratic solver such as https://github.com/archermarx/quadratic ?
-        // auto [X1, X2] = quadratic::solve(A, B, C);
+    const double dd = B*B - 4*A*C;
 
-        isect0 = {X1, m* X1 + b};
-        isect1 = {X2, m* X2 + b};
+    if (dd < 0) {
+        return 0;
     }
 
+    // TODO use robust quadratic solver such as https://github.com/archermarx/quadratic ?
+    // auto [X1, X2] = quadratic::solve(A, B, C);
+
+    const double d = std::sqrt(dd);
+    const double X1 = (-B + d)/(2*A);
+    const double X2 = (-B - d)/(2*A);
+
+    isect0 = {X1, m* X1 + b};
+    if (d == 0) {
+        return 1;
+    }
+
+    isect1 = {X2, m* X2 + b};
+    return 2;
+}
+
+int
+CircularArcs::circleIntersectsSegment(const CoordinateXY& center, double r,
+                                      const CoordinateXY& p0, const CoordinateXY& p1,
+                                      CoordinateXY& ret0, CoordinateXY& ret1)
+{
+    CoordinateXY isect0, isect1;
+
+    auto n = circleIntersectsLine(center, r, p0, p1, isect0, isect1);
+
+    if (n == 0) {
+        return 0;
+    }
+
+    Envelope segEnv(p0, p1);
+
     if (segEnv.intersects(isect0)) {
         ret0 = isect0;
-        if (segEnv.intersects(isect1) && !isect1.equals2D(isect0)) {
+        if (n > 1 && segEnv.intersects(isect1)) {
             ret1 = isect1;
-            n = 2;
-        } else {
-            n = 1;
+            return 2;
         }
-    } else if (segEnv.intersects(isect1)) {
-        ret0 = isect1;
-        n = 1;
+
+        return 1;
     }
 
-    return n;
+    if (segEnv.intersects(isect1)) {
+        ret0 = isect1;
+        return 1;
+    }
+
+    return 0;
 }
 
 bool
diff --git a/tests/unit/algorithm/CircularArcIntersectorTest.cpp b/tests/unit/algorithm/CircularArcIntersectorTest.cpp
index 928a3df90..e9899213d 100644
--- a/tests/unit/algorithm/CircularArcIntersectorTest.cpp
+++ b/tests/unit/algorithm/CircularArcIntersectorTest.cpp
@@ -1712,6 +1712,26 @@ void object::test<85>()
     ensure_equals(cai1.getPoint(0), cai2.getPoint(0));
 }
 
+template<>
+template<>
+void object::test<86>()
+{
+    // arc/segment with single endpoint intersection
+
+    CircularArcIntersector cai;
+
+    auto arc = CircularArc::create(XY{-0.84333168960872817, -0.1241204385865409}, XY{-0.96461319189094762, -0.20729352391791989}, XY{-1.1087328289561522, -0.23655946199558511});
+
+    CoordinateSequence seg{
+     XY{-1.277492733105557, 0.28999497465537871}, XY{-0.84333168960872817, -0.1241204385865409}};
+
+    cai.intersects(arc, seg, 0, 1, false);
+
+    ensure_equals(cai.getNumPoints(), 1u);
+    // ensure endpoint intersection is represented exactly, not with distance() == 0
+    ensure_equals(cai.getPoint(0), seg.getAt<CoordinateXY>(1));
+}
+
 
 // TODO: check Z values of arc result centerpoints
 // TODO: add tests for seg/seg

commit f14c453ade3f86a98b3dafeaf5cca750593d4e70
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri May 15 14:12:27 2026 -0400

    Edge: simplify direction() logic

diff --git a/include/geos/operation/overlayng/Edge.h b/include/geos/operation/overlayng/Edge.h
index 83f67dc6a..b88a44fe7 100644
--- a/include/geos/operation/overlayng/Edge.h
+++ b/include/geos/operation/overlayng/Edge.h
@@ -230,25 +230,22 @@ public:
             throw util::GEOSException("Edge must have >= 2 points");
         }
 
-        const geom::Coordinate& p0 = pts->getAt(0);
-        const geom::Coordinate& p1 = pts->getAt(1);
-        const geom::Coordinate& pn0 = pts->getAt(pts->size() - 1);
-        const geom::Coordinate& pn1 = pts->getAt(pts->size() - 2);
+        const geom::CoordinateXY& p0 = getCoordinate(0);
+        const geom::CoordinateXY& pn0 = getCoordinate(pts->size() - 1);
 
-        int cmp = 0;
-        int cmp0 = p0.compareTo(pn0);
-        if (cmp0 != 0) cmp = cmp0;
-
-        if (cmp == 0) {
-            int cmp1 = p1.compareTo(pn1);
-            if (cmp1 != 0) cmp = cmp1;
+        const int cmp0 = p0.compareTo(pn0);
+        if (cmp0 != 0) {
+            return cmp0 == -1;
         }
 
-        if (cmp == 0) {
-            throw util::GEOSException("Edge direction cannot be determined because endpoints are equal");
+        const geom::CoordinateXY& p1 = getCoordinate(1);
+        const geom::CoordinateXY& pn1 = getCoordinate(pts->size() - 2);
+        const int cmp1 = p1.compareTo(pn1);
+        if (cmp1 != 0) {
+            return cmp1 == -1;
         }
 
-        return cmp == -1;
+        throw util::GEOSException("Edge direction cannot be determined because endpoints are equal");
     };
 
     /**

commit dc3935ba35f5fd6328bddb3637c7e0eeba307dd8
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri May 15 14:09:56 2026 -0400

    NodableArcString: Split ArcStrings when intersection point is already a node

diff --git a/src/noding/NodableArcString.cpp b/src/noding/NodableArcString.cpp
index d16acafd5..4b824b3fa 100644
--- a/src/noding/NodableArcString.cpp
+++ b/src/noding/NodableArcString.cpp
@@ -16,6 +16,7 @@
 #include <geos/algorithm/Angle.h>
 
 #include <algorithm>
+#include <iomanip>
 
 using geos::geom::CoordinateXYZM;
 using geos::geom::CircularArc;
@@ -26,7 +27,7 @@ static double
 pseudoAngleDiffCCW(double paStart, double pa) {
     double diff = pa - paStart;
 
-    if (diff <= 0) {
+    if (diff < 0) {
         diff += 4;
     }
 
@@ -45,31 +46,32 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
 {
     const bool isCCW = arc.getOrientation() == algorithm::Orientation::COUNTERCLOCKWISE;
     const geom::CoordinateXY& center = arc.getCenter();
-    const double paStart = geom::Quadrant::pseudoAngle(center, arc.p0());
+
+    // Some potential split points may be skipped, for example, if they would create an arc section that is
+    // too short to have a constructed midpoint. Because the results of this logic could depend on the
+    // direction in which the arc is processed, we reverse clockwise arcs and then reverse the list of
+    // retained points.
+    const double paStart = geom::Quadrant::pseudoAngle(center, isCCW ? arc.p0() : arc.p2());
 
     std::vector<CoordinateXYZM> retained;
     // Add starting point of input arc
     {
         CoordinateXYZM p0;
-        arc.getCoordinateSequence()->getAt(arc.getCoordinatePosition(), p0);
+        arc.getCoordinateSequence()->getAt(arc.getCoordinatePosition() + (isCCW ? 0 : 2), p0);
         retained.push_back(p0);
     }
 
-    std::sort(splitPoints.begin(), splitPoints.end(), [&center, paStart, isCCW](const auto& p0, const auto& p1) {
+    std::sort(splitPoints.begin(), splitPoints.end(), [&center, paStart](const auto& p0, const auto& p1) {
         double pa0 = geom::Quadrant::pseudoAngle(center, p0);
         double pa1 = geom::Quadrant::pseudoAngle(center, p1);
 
-        if (isCCW) {
-            return pseudoAngleDiffCCW(paStart, pa0) < pseudoAngleDiffCCW(paStart, pa1);
-        } else {
-            return pseudoAngleDiffCCW(paStart, pa0) > pseudoAngleDiffCCW(paStart, pa1);
-        }
+        return pseudoAngleDiffCCW(paStart, pa0) < pseudoAngleDiffCCW(paStart, pa1);
     });
 
     // Add ending point of input arc
     {
         CoordinateXYZM p2;
-        arc.getCoordinateSequence()->getAt(arc.getCoordinatePosition() + 2, p2);
+        arc.getCoordinateSequence()->getAt(arc.getCoordinatePosition() + (isCCW ? 2 : 0), p2);
         splitPoints.push_back(p2);
     }
 
@@ -90,23 +92,21 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
             continue;
         }
 
-        const auto p1 = algorithm::CircularArcs::getMidpoint(p0, p2, center, arc.getRadius(), isCCW);
+        // Calculate the midpoint of an arc between p0 and p2.
+        // We don't actually use the calculated point here, we just want to make sure that
+        // the arc from p0 to p2 is long enough to contain a midpoint.
+        const geom::CoordinateXY p1 = algorithm::CircularArcs::getMidpoint(p0, p2, center, arc.getRadius(), true);
 
         if (p1.equals2D(p0) || p1.equals2D(p2)) {
             continue;
         }
 
-        // Reject split point where sub-arc midpoint doesn't fall inside arc
-        if (!arc.containsPointOnCircle(p1)) {
-            continue;
-        }
-
         // Reject split point where computed doesn't fall between endpoints
-        const double t0 = algorithm::Angle::normalizePositive(arc.theta0());
+        const double t0 = algorithm::Angle::normalizePositive(isCCW ? arc.theta0() : arc.theta2());
         const double t1 = algorithm::Angle::normalizePositive(algorithm::CircularArcs::getAngle(p1, center));
-        const double t2 = algorithm::Angle::normalizePositive(algorithm::CircularArcs::getAngle(p2, center));
+        const double t2 = algorithm::Angle::normalizePositive(isCCW ? arc.theta2() : arc.theta0());
 
-        if (algorithm::Angle::isWithinCCW(t1, t0, t2) != isCCW) {
+        if (!algorithm::Angle::isWithinCCW(t1, t0, t2)) {
             continue;
         }
 
@@ -116,7 +116,7 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
     // Make sure that endpoint of split arc is unchanged
     {
         CoordinateXYZM p2;
-        arc.getCoordinateSequence()->getAt(arc.getCoordinatePosition() + 2, p2);
+        arc.getCoordinateSequence()->getAt(arc.getCoordinatePosition() + (isCCW ? 2 : 0), p2);
         CoordinateXYZM& back = retained.back();
 
         if (!back.equals2D(p2)) {
@@ -131,6 +131,10 @@ std::vector<CoordinateXYZM> prepareArcPoints(const CircularArc& arc, std::vector
         }
     }
 
+    if (!isCCW) {
+        std::reverse(retained.begin(), retained.end());
+    }
+
     return retained;
 }
 
@@ -146,16 +150,19 @@ NodableArcString::getNoded(std::vector<std::unique_ptr<ArcString>>& splitArcs) {
         const int orientation = toSplit.getOrientation();
 
         bool arcIsSplit = true;
+        bool createArcString = true;
         const bool preserveControlPoint = true;
         std::vector<CoordinateXYZM> arcPoints;
         const auto it = m_adds.find(arcIndex);
         if (it == m_adds.end()) {
             arcIsSplit = false;
+            createArcString = false;
         } else {
             arcPoints = prepareArcPoints(toSplit, it->second);
 
             if (arcPoints.size() == 2) {
                 // All added nodes collapsed
+                // Still need to know if arc was split.
                 arcIsSplit = false;
             }
         }
@@ -168,6 +175,12 @@ NodableArcString::getNoded(std::vector<std::unique_ptr<ArcString>>& splitArcs) {
             std::size_t dstPos = dstSeq->getSize() - 3;
             arcs.emplace_back(*dstSeq, dstPos, center, radius, orientation);
 
+            if (createArcString) {
+                splitArcs.push_back(std::make_unique<NodableArcString>(std::move(arcs), std::move(dstSeq), m_constructZ, m_constructM, getData()));
+                dstSeq = std::make_unique<geom::CoordinateSequence>(0, m_constructZ, m_constructM);
+                arcs.clear();
+            }
+
             continue;
         }
 
diff --git a/tests/unit/capi/GEOSNodeTest.cpp b/tests/unit/capi/GEOSNodeTest.cpp
index 8feb5df96..63d893a55 100644
--- a/tests/unit/capi/GEOSNodeTest.cpp
+++ b/tests/unit/capi/GEOSNodeTest.cpp
@@ -235,10 +235,10 @@ void object::test<10>()
     ensure(result_ != nullptr);
 
     expected_ = fromWKT("MULTICURVE ZM ("
-        "CIRCULARSTRING ZM (-1 0 3 4, -0.7071067812 0.7071067812 2.5 6.5, -5.5511151231e-17 1 2 9),"
-        "CIRCULARSTRING ZM (-5.5511151231e-17 1 2 9, 0.7071067812 0.7071067812 3 8, 1 0 4 7),"
-        "CIRCULARSTRING ZM (-1 2 NaN 9, -0.2928932188 1.7071067812 NaN 9, -5.5511151231e-17 1 2 9),"
-        "CIRCULARSTRING ZM (-5.5511151231e-17 1 2 9, -0.2928932188 0.2928932188 2.5 6.5, -1 0 3 4))");
+        "CIRCULARSTRING ZM (-1 0 3 4, -0.7071067812 0.7071067812 2.5 6.5, 0 1 2 9),"
+        "CIRCULARSTRING ZM (0 1 2 9, 0.7071067812 0.7071067812 3 8, 1 0 4 7),"
+        "CIRCULARSTRING ZM (-1 2 NaN 9, -0.2928932188 1.7071067812 NaN 9, 0 1 2 9),"
+        "CIRCULARSTRING ZM (0 1 2 9, -0.2928932188 0.2928932188 2.5 13, -1 0 3 17))");
 
     ensure_equals(GEOSGetNumGeometries(result_), 4);
 
diff --git a/tests/unit/geom/CircularStringTest.cpp b/tests/unit/geom/CircularStringTest.cpp
index ee4e26058..3678746c9 100644
--- a/tests/unit/geom/CircularStringTest.cpp
+++ b/tests/unit/geom/CircularStringTest.cpp
@@ -138,9 +138,9 @@ void object::test<3>()
 
     // Overlay
     ensure_THROW(cs_->Union(), geos::util::UnsupportedOperationException);
-    ensure_equals_geometry(cs_->Union(cs_.get()).get(), static_cast<const Geometry*>(cs_.get()));
+    ensure_equals(cs_->Union(cs_.get())->getLength(), cs_->getLength());
     ensure(cs_->difference(cs_.get())->isEmpty());
-    ensure_equals_geometry(cs_->intersection(cs_.get()).get(), static_cast<const Geometry*>(cs_.get()));
+    ensure_equals(cs_->intersection(cs_.get())->getLength(), cs_->getLength());
     ensure(cs_->symDifference(cs_.get())->isEmpty());
 
     // Distance
diff --git a/tests/unit/geom/CurvePolygonTest.cpp b/tests/unit/geom/CurvePolygonTest.cpp
index 07c3faad1..012fa8305 100644
--- a/tests/unit/geom/CurvePolygonTest.cpp
+++ b/tests/unit/geom/CurvePolygonTest.cpp
@@ -166,9 +166,9 @@ void object::test<3>()
 
     // Overlay
     ensure_THROW(cp_->Union(), geos::util::UnsupportedOperationException);
-    ensure_equals_geometry(cp_->Union(cp_.get()).get(), static_cast<const Geometry*>(cp_.get()));
+    ensure_equals(cp_->Union(cp_.get())->getLength(), cp_->getLength());
     ensure(cp_->difference(cp_.get())->isEmpty());
-    ensure_equals_geometry(cp_->intersection(cp_.get()).get(), static_cast<const Geometry*>(cp_.get()));
+    ensure_equals(cp_->intersection(cp_.get())->getLength(), cp_->getLength());
     ensure(cp_->symDifference(cp_.get())->isEmpty());
 
     // Distance
diff --git a/tests/unit/operation/overlayng/OverlayNGTest.cpp b/tests/unit/operation/overlayng/OverlayNGTest.cpp
index d7077e57a..46b8155fa 100644
--- a/tests/unit/operation/overlayng/OverlayNGTest.cpp
+++ b/tests/unit/operation/overlayng/OverlayNGTest.cpp
@@ -780,7 +780,7 @@ template<>
 template<>
 void object::test<60>()
 {
-    set_test_name("MultiSurface / MultiPoint -> MultiSurface");
+    set_test_name("Union of MultiSurface / MultiPoint -> MultiSurface");
 
     std::string a = "MULTISURFACE(CURVEPOLYGON (COMPOUNDCURVE( CIRCULARSTRING(-5 0, 0 5, 5 0), (5 0, -5 0))), ((4 4, 5 4, 5 5, 4 4)))";
     std::string b = "MULTIPOINT (0 0, 4 3, 2 2, 4.5 4.1)";
@@ -789,4 +789,33 @@ void object::test<60>()
     testOverlay(a, b, exp, OverlayNG::UNION, 0);
 }
 
+template<>
+template<>
+void object::test<61>()
+{
+    set_test_name("Union of CurvePolygon / CurvePolygon -> CurvePolygon");
+
+    std::string a = "CURVEPOLYGON (CIRCULARSTRING (-5 0, 0 5, 5 0, 0 4, -5 0))";
+    std::string b = "CURVEPOLYGON (COMPOUNDCURVE((-5 0, 5 0), CIRCULARSTRING (5 0, 0 4, -5 0)))";
+
+    std::string exp = "CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (-5 0, 0 5, 5 0), (5 0, -5 0)))";
+
+    testOverlay(a, b, exp, OverlayNG::UNION, 0);
+}
+
+template<>
+template<>
+void object::test<62>()
+{
+    set_test_name("CircularString self-union");
+
+    std::string a = "CIRCULARSTRING (0 0, 1 1, 2 0, 3 -1, 4 0)";
+
+    // Noding causes the CircularString to split at (2, 0)
+    // OverlayNG does not merge output lines, so we get a MultiCurve.
+    std::string exp = "MULTICURVE (CIRCULARSTRING (0 0, 1 1, 2 0), CIRCULARSTRING (2 0, 3 -1, 4 0))";
+
+    testOverlay(a, a, exp, OverlayNG::UNION, 0);
+}
+
 } // namespace tut

commit 1aeef7493bc6d0804d094021fc1013a7227791af
Author: Daniel Baston <dbaston at gmail.com>
Date:   Thu May 14 15:57:06 2026 -0400

    CircularArcIntersector: Calc intersection points independently of argument order

diff --git a/src/algorithm/CircularArcIntersector.cpp b/src/algorithm/CircularArcIntersector.cpp
index b5e6adcc3..c63cd2c55 100644
--- a/src/algorithm/CircularArcIntersector.cpp
+++ b/src/algorithm/CircularArcIntersector.cpp
@@ -163,11 +163,15 @@ CircularArcIntersector::intersects(const CircularArc& arc1, const CircularArc& a
 
     reset();
 
-    const auto& c1 = arc1.getCenter();
-    const auto& c2 = arc2.getCenter();
+    // Normalize arguments such that the computed intersection points do not depend
+    // on the order of the input arcs
+    const bool swapArgs = arc1.getCenter().compareTo(arc2.getCenter()) > 0;
 
-    const auto r1 = arc1.getRadius();
-    const auto r2 = arc2.getRadius();
+    const auto c1 = swapArgs ? arc2.getCenter() : arc1.getCenter();
+    const auto c2 = swapArgs ? arc1.getCenter() : arc2.getCenter();
+
+    const auto r1 = swapArgs ? arc2.getRadius() : arc1.getRadius();
+    const auto r2 = swapArgs ? arc1.getRadius() : arc2.getRadius();
 
     const auto d = c1.distance(c2);
 
diff --git a/tests/unit/algorithm/CircularArcIntersectorTest.cpp b/tests/unit/algorithm/CircularArcIntersectorTest.cpp
index 6ad649d02..928a3df90 100644
--- a/tests/unit/algorithm/CircularArcIntersectorTest.cpp
+++ b/tests/unit/algorithm/CircularArcIntersectorTest.cpp
@@ -1692,6 +1692,26 @@ void object::test<84>()
     ensure_equals(cai.getPoint(0), XY{31.8, 68.2});
 }
 
+template<>
+template<>
+void object::test<85>()
+{
+    set_test_name("computed test points are independent of argument order");
+
+    auto arc0 = CircularArc::create(XY{0, 5}, XY{3, 4}, XY{4, 3});
+    auto arc1 = CircularArc::create(XY{3, 5}, XY{4, 4}, XY{2, 3});
+
+    CircularArcIntersector cai1;
+    cai1.intersects(arc0, arc1);
+    ensure_equals(cai1.getNumPoints(), 1u);
+
+    CircularArcIntersector cai2;
+    cai2.intersects(arc1, arc0);
+    ensure_equals(cai2.getNumPoints(), 1u);
+
+    ensure_equals(cai1.getPoint(0), cai2.getPoint(0));
+}
+
 
 // TODO: check Z values of arc result centerpoints
 // TODO: add tests for seg/seg

commit b0506ea14bdc0339fb8ab61eb95ba5ec26762332
Author: Daniel Baston <dbaston at gmail.com>
Date:   Thu May 14 13:51:20 2026 -0400

    OverlayUtil: Add getDirectionPoint

diff --git a/include/geos/operation/overlayng/OverlayUtil.h b/include/geos/operation/overlayng/OverlayUtil.h
index 25fa99312..5a83bda6a 100644
--- a/include/geos/operation/overlayng/OverlayUtil.h
+++ b/include/geos/operation/overlayng/OverlayUtil.h
@@ -205,6 +205,9 @@ public:
     */
     static bool round(const Point* pt, const PrecisionModel* pm, Coordinate& rsltCoord);
 
+    static geom::CoordinateXY
+    getDirectionPoint(const CoordinateSequence& pts, bool forward, bool isCurved);
+
     template<typename T>
     static void moveGeometry(std::vector<std::unique_ptr<T>>& inGeoms, std::vector<std::unique_ptr<Geometry>>& outGeoms)
     {
diff --git a/src/operation/overlayng/OverlayGraph.cpp b/src/operation/overlayng/OverlayGraph.cpp
index 7fd39fefd..8fc1de1ca 100644
--- a/src/operation/overlayng/OverlayGraph.cpp
+++ b/src/operation/overlayng/OverlayGraph.cpp
@@ -14,8 +14,8 @@
 
 #include <geos/operation/overlayng/OverlayGraph.h>
 
-#include <geos/algorithm/CircularArcs.h>
 #include <geos/operation/overlayng/Edge.h>
+#include <geos/operation/overlayng/OverlayUtil.h>
 #include <geos/geom/Coordinate.h>
 #include <geos/geom/CoordinateSequence.h>
 #include <geos/geom/CircularArc.h>
@@ -105,28 +105,6 @@ OverlayGraph::createEdgePair(const std::shared_ptr<const CoordinateSequence>& pt
     return e0;
 }
 
-static CoordinateXY
-getDirectionPoint(const CoordinateSequence& pts, bool forward, bool isCurved)
-{
-    if (isCurved) {
-        assert(pts.size() >= 3);
-        if (forward) {
-            CircularArc arc(pts, 0);
-            return arc.getDirectionPoint();
-        } else {
-            CircularArc arc(pts, pts.size() - 3);
-            return algorithm::CircularArcs::getDirectionPoint(arc.getCenter(), arc.getRadius(), arc.theta2(), !arc.isCCW());
-        }
-    }
-
-    assert(pts.size() >= 2);
-    if (forward) {
-        return pts.getAt<CoordinateXY>(1);
-    }
-
-    return pts.getAt<CoordinateXY>(pts.size() - 2);
-}
-
 /*private*/
 OverlayEdge*
 OverlayGraph::createOverlayEdge(const std::shared_ptr<const CoordinateSequence>& pts, OverlayLabel* lbl, bool direction, bool isCurved)
@@ -134,7 +112,7 @@ OverlayGraph::createOverlayEdge(const std::shared_ptr<const CoordinateSequence>&
     assert(pts->size() >= 2);
 
     CoordinateXYZM origin;
-    const CoordinateXY dirPt = getDirectionPoint(*pts, direction, isCurved);
+    const CoordinateXY dirPt = OverlayUtil::getDirectionPoint(*pts, direction, isCurved);
 
     if (direction) {
         pts->getAt(0, origin);
diff --git a/src/operation/overlayng/OverlayUtil.cpp b/src/operation/overlayng/OverlayUtil.cpp
index 313837a34..077ca2efb 100644
--- a/src/operation/overlayng/OverlayUtil.cpp
+++ b/src/operation/overlayng/OverlayUtil.cpp
@@ -338,6 +338,28 @@ OverlayUtil::round(const Point* pt, const PrecisionModel* pm, Coordinate& rsltCo
     return true;
 }
 
+CoordinateXY
+OverlayUtil::getDirectionPoint(const CoordinateSequence& pts, bool forward, bool isCurved)
+{
+    if (isCurved) {
+        assert(pts.size() >= 3);
+        if (forward) {
+            CircularArc arc(pts, 0);
+            return arc.getDirectionPoint();
+        } else {
+            CircularArc arc(pts, pts.size() - 3);
+            return algorithm::CircularArcs::getDirectionPoint(arc.getCenter(), arc.getRadius(), arc.theta2(), !arc.isCCW());
+        }
+    }
+
+    assert(pts.size() >= 2);
+    if (forward) {
+        return pts.getAt<CoordinateXY>(1);
+    }
+
+    return pts.getAt<CoordinateXY>(pts.size() - 2);
+}
+
 
 
 } // namespace geos.operation.overlayng

commit 43edb6d35a6c66fe82712033bb3abd53f89fce3a
Author: Daniel Baston <dbaston at gmail.com>
Date:   Tue Apr 14 06:12:17 2026 -0400

    EdgeNodingBuilder: Automatically use SimpleNoder for curved inputs

diff --git a/include/geos/operation/overlayng/EdgeNodingBuilder.h b/include/geos/operation/overlayng/EdgeNodingBuilder.h
index d981a51d5..8d34ceffd 100644
--- a/include/geos/operation/overlayng/EdgeNodingBuilder.h
+++ b/include/geos/operation/overlayng/EdgeNodingBuilder.h
@@ -18,6 +18,7 @@
 
 #pragma once
 
+#include <geos/algorithm/CircularArcIntersector.h>
 #include <geos/algorithm/LineIntersector.h>
 #include <geos/geom/CoordinateSequence.h>
 #include <geos/geom/CircularArc.h>
@@ -28,6 +29,7 @@
 #include <geos/geom/LineString.h>
 #include <geos/geom/Polygon.h>
 #include <geos/geom/SimpleCurve.h>
+#include <geos/noding/ArcIntersectionAdder.h>
 #include <geos/noding/IntersectionAdder.h>
 #include <geos/noding/Noder.h>
 #include <geos/noding/SegmentString.h>
@@ -95,7 +97,9 @@ private:
 
     // For use in createFloatingPrecisionNoder()
     algorithm::LineIntersector lineInt;
+    algorithm::CircularArcIntersector arcInt;
     noding::IntersectionAdder intAdder;
+    noding::ArcIntersectionAdder arcIntAdder;
     std::unique_ptr<noding::Noder> internalNoder;
     std::unique_ptr<noding::Noder> spareInternalNoder;
     // EdgeSourceInfo*, Edge* owned by EdgeNodingBuilder, stored in deque
@@ -103,6 +107,7 @@ private:
     std::deque<Edge> edgeQue;
     bool inputHasZ;
     bool inputHasM;
+    bool inputHasCurves;
 
     /**
     * Gets a noder appropriate for the precision model supplied.
@@ -207,8 +212,10 @@ public:
         , hasEdges{{false,false}}
         , clipEnv(nullptr)
         , intAdder(lineInt)
+        , arcIntAdder(arcInt)
         , inputHasZ(false)
         , inputHasM(false)
+        , inputHasCurves(false)
         {};
 
     ~EdgeNodingBuilder();
diff --git a/src/operation/overlayng/EdgeNodingBuilder.cpp b/src/operation/overlayng/EdgeNodingBuilder.cpp
index 13c123315..ded0c128b 100644
--- a/src/operation/overlayng/EdgeNodingBuilder.cpp
+++ b/src/operation/overlayng/EdgeNodingBuilder.cpp
@@ -23,6 +23,7 @@
 #include <geos/noding/NodedSegmentString.h>
 #include <geos/noding/MCIndexNoder.h>
 #include <geos/noding/NodableArcString.h>
+#include <geos/noding/SimpleNoder.h>
 #include <geos/noding/snapround/SnapRoundingNoder.h>
 #include <geos/operation/overlayng/EdgeNodingBuilder.h>
 #include <geos/operation/overlayng/EdgeMerger.h>
@@ -43,6 +44,7 @@ using geos::noding::NodableArcString;
 using geos::noding::MCIndexNoder;
 using geos::noding::ValidatingNoder;
 using geos::noding::SegmentString;
+using geos::noding::SimpleNoder;
 using geos::noding::NodedSegmentString;
 using geos::noding::PathString;
 
@@ -83,16 +85,26 @@ EdgeNodingBuilder::createFixedPrecisionNoder(const PrecisionModel* p_pm)
 std::unique_ptr<Noder>
 EdgeNodingBuilder::createFloatingPrecisionNoder(bool doValidation)
 {
-    std::unique_ptr<MCIndexNoder> mcNoder(new MCIndexNoder());
-    mcNoder->setSegmentIntersector(&intAdder);
+    std::unique_ptr<Noder> ret;
 
-    if (doValidation) {
-        spareInternalNoder = std::move(mcNoder);
+    if (inputHasCurves) {
+        auto simpleNoder = std::make_unique<SimpleNoder>();
+        simpleNoder->setArcIntersector(arcIntAdder);
+        ret = std::move(simpleNoder);
+    } else {
+        auto mcNoder = std::make_unique<MCIndexNoder>();
+        mcNoder->setSegmentIntersector(&intAdder);
+        ret = std::move(mcNoder);
+    }
+
+    // TODO: Support arcs in ValidatingNoder
+    if (doValidation && !inputHasCurves) {
+        spareInternalNoder = std::move(ret);
         std::unique_ptr<Noder> validNoder(new ValidatingNoder(*spareInternalNoder));
         return validNoder;
     }
 
-    return std::unique_ptr<Noder>(mcNoder.release());
+    return ret;
 }
 
 /*public*/
@@ -110,6 +122,7 @@ EdgeNodingBuilder::build(const Geometry* geom0, const Geometry* geom1)
 {
     inputHasZ = geom0->hasZ() || (geom1 != nullptr && geom1->hasZ());
     inputHasM = geom0->hasM() || (geom1 != nullptr && geom1->hasM());
+    inputHasCurves = geom0->hasCurvedComponents() || (geom1 != nullptr && geom1->hasCurvedComponents());
 
     add(geom0, 0);
     add(geom1, 1);
diff --git a/src/operation/overlayng/OverlayNGRobust.cpp b/src/operation/overlayng/OverlayNGRobust.cpp
index e9af20896..258a7ecda 100644
--- a/src/operation/overlayng/OverlayNGRobust.cpp
+++ b/src/operation/overlayng/OverlayNGRobust.cpp
@@ -83,9 +83,6 @@ OverlayNGRobust::Union(const Geometry* a)
 std::unique_ptr<Geometry>
 OverlayNGRobust::Overlay(const Geometry* geom0, const Geometry* geom1, int opCode)
 {
-    geos::util::ensureNoCurvedComponents(geom0);
-    geos::util::ensureNoCurvedComponents(geom1);
-
     std::unique_ptr<Geometry> result;
     std::runtime_error exOriginal("");
 
diff --git a/tests/unit/capi/GEOSDifferenceTest.cpp b/tests/unit/capi/GEOSDifferenceTest.cpp
index d739b0936..841f49188 100644
--- a/tests/unit/capi/GEOSDifferenceTest.cpp
+++ b/tests/unit/capi/GEOSDifferenceTest.cpp
@@ -63,6 +63,8 @@ template<>
 template<>
 void object::test<3>()
 {
+    set_test_name("curved inputs");
+
     geom1_ = fromWKT("CIRCULARSTRING (0 0, 1 1, 2 0)");
     geom2_ = fromWKT("LINESTRING (1 0, 2 1)");
 
@@ -70,7 +72,11 @@ void object::test<3>()
     ensure(geom2_);
 
     result_ = GEOSDifference(geom1_, geom2_);
-    ensure("curved geometry not supported", result_ == nullptr);
+    ensure(result_);
+
+    expected_ = fromWKT("MULTICURVE (CIRCULARSTRING (1.7071067812 0.7071067812, 1.9238795325 0.3826834324, 2 0), CIRCULARSTRING (0 0, 0.6173165676 0.9238795325, 1.7071067812 0.7071067812))");
+
+    ensure_geometry_equals(result_, expected_, 1e-8);
 }
 
 } // namespace tut
diff --git a/tests/unit/capi/GEOSIntersectionTest.cpp b/tests/unit/capi/GEOSIntersectionTest.cpp
index 4a03845df..a4aabb439 100644
--- a/tests/unit/capi/GEOSIntersectionTest.cpp
+++ b/tests/unit/capi/GEOSIntersectionTest.cpp
@@ -149,14 +149,16 @@ template<>
 template<>
 void object::test<8>()
 {
+    set_test_name("curved input");
+
     geom1_ = fromWKT("CIRCULARSTRING (0 0, 1 1, 2 0)");
     geom2_ = fromWKT("LINESTRING (1 0, 2 1)");
 
-    ensure(geom1_);
-    ensure(geom2_);
-
     result_ = GEOSIntersection(geom1_, geom2_);
-    ensure("curved geometry not supported", result_ == nullptr);
+    ensure(result_);
+
+    expected_ = fromWKT("POINT (1.7071067812 0.7071067812)");
+    ensure_geometry_equals(result_, expected_, 1e-8);
 }
 
 // https://github.com/libgeos/geos/issues/1074
diff --git a/tests/unit/capi/GEOSSymDifferenceTest.cpp b/tests/unit/capi/GEOSSymDifferenceTest.cpp
index def092b68..63436e135 100644
--- a/tests/unit/capi/GEOSSymDifferenceTest.cpp
+++ b/tests/unit/capi/GEOSSymDifferenceTest.cpp
@@ -33,14 +33,16 @@ template<>
 template<>
 void object::test<2>()
 {
+    set_test_name("curved inputs");
+
     geom1_ = fromWKT("CIRCULARSTRING (0 0, 1 1, 2 0)");
     geom2_ = fromWKT("LINESTRING (1 0, 2 1)");
 
-    ensure(geom1_);
-    ensure(geom2_);
-
     result_ = GEOSSymDifference(geom1_, geom2_);
-    ensure("curved geometry not supported", result_ == nullptr);
+    ensure(result_);
+
+    expected_ = fromWKT("MULTICURVE (CIRCULARSTRING (1.7071067812 0.7071067812, 1.9238795325 0.3826834324, 2 0), CIRCULARSTRING (0 0, 0.6173165676 0.9238795325, 1.7071067812 0.7071067812), (1.7071067812 0.7071067812, 2 1), (1 0, 1.7071067812 0.7071067812))");
+    ensure_geometry_equals(result_, expected_, 1e-8);
 }
 
 } // namespace tut
diff --git a/tests/unit/capi/GEOSUnionTest.cpp b/tests/unit/capi/GEOSUnionTest.cpp
index 68c90867b..4c7e89e29 100644
--- a/tests/unit/capi/GEOSUnionTest.cpp
+++ b/tests/unit/capi/GEOSUnionTest.cpp
@@ -66,14 +66,16 @@ template<>
 template<>
 void object::test<3>()
 {
+    set_test_name("curved inputs");
+
     geom1_ = fromWKT("CIRCULARSTRING (0 0, 1 1, 2 0)");
     geom2_ = fromWKT("LINESTRING (1 0, 2 1)");
 
-    ensure(geom1_);
-    ensure(geom2_);
-
     result_ = GEOSUnion(geom1_, geom2_);
-    ensure("curved geometry not supported", result_ == nullptr);
+    ensure(result_);
+
+    expected_ = fromWKT("MULTICURVE (CIRCULARSTRING (1.7071067812 0.7071067812, 1.9238795325 0.3826834324, 2 0), CIRCULARSTRING (0 0, 0.6173165676 0.9238795325, 1.7071067812 0.7071067812), (1.7071067812 0.7071067812, 2 1), (1 0, 1.7071067812 0.7071067812))");
+    ensure_geometry_equals(result_, expected_, 1e-8);
 }
 
 } // namespace tut
diff --git a/tests/unit/geom/CircularStringTest.cpp b/tests/unit/geom/CircularStringTest.cpp
index a31b70769..ee4e26058 100644
--- a/tests/unit/geom/CircularStringTest.cpp
+++ b/tests/unit/geom/CircularStringTest.cpp
@@ -138,10 +138,10 @@ void object::test<3>()
 
     // Overlay
     ensure_THROW(cs_->Union(), geos::util::UnsupportedOperationException);
-    ensure_THROW(cs_->Union(cs_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cs_->difference(cs_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cs_->intersection(cs_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cs_->symDifference(cs_.get()), geos::util::UnsupportedOperationException);
+    ensure_equals_geometry(cs_->Union(cs_.get()).get(), static_cast<const Geometry*>(cs_.get()));
+    ensure(cs_->difference(cs_.get())->isEmpty());
+    ensure_equals_geometry(cs_->intersection(cs_.get()).get(), static_cast<const Geometry*>(cs_.get()));
+    ensure(cs_->symDifference(cs_.get())->isEmpty());
 
     // Distance
     ensure_equals(cs_->distance(cs_.get()), 0);
diff --git a/tests/unit/geom/CompoundCurveTest.cpp b/tests/unit/geom/CompoundCurveTest.cpp
index cc2f79cd8..4d52c66ef 100644
--- a/tests/unit/geom/CompoundCurveTest.cpp
+++ b/tests/unit/geom/CompoundCurveTest.cpp
@@ -164,10 +164,11 @@ void object::test<3>()
 
     // Overlay
     ensure_THROW(cc_->Union(), geos::util::UnsupportedOperationException);
-    ensure_THROW(cc_->Union(cc_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cc_->difference(cc_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cc_->intersection(cc_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cc_->symDifference(cc_.get()), geos::util::UnsupportedOperationException);
+    // TODO: Prevent overlay from degrading CompoundCurve into MultiCurve
+    //ensure_equals_geometry(cc_->Union(cc_.get()).get(), static_cast<const Geometry*>(cc_.get()));
+    ensure(cc_->difference(cc_.get())->isEmpty());
+    //ensure_equals_geometry(cc_->intersection(cc_.get()).get(), static_cast<const Geometry*>(cc_.get()));
+    ensure(cc_->symDifference(cc_.get())->isEmpty());
 
     // Distance
     ensure_equals(cc_->distance(cc_.get()), 0);
diff --git a/tests/unit/geom/CurvePolygonTest.cpp b/tests/unit/geom/CurvePolygonTest.cpp
index c41dab112..07c3faad1 100644
--- a/tests/unit/geom/CurvePolygonTest.cpp
+++ b/tests/unit/geom/CurvePolygonTest.cpp
@@ -166,10 +166,10 @@ void object::test<3>()
 
     // Overlay
     ensure_THROW(cp_->Union(), geos::util::UnsupportedOperationException);
-    ensure_THROW(cp_->Union(cp_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cp_->difference(cp_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cp_->intersection(cp_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(cp_->symDifference(cp_.get()), geos::util::UnsupportedOperationException);
+    ensure_equals_geometry(cp_->Union(cp_.get()).get(), static_cast<const Geometry*>(cp_.get()));
+    ensure(cp_->difference(cp_.get())->isEmpty());
+    ensure_equals_geometry(cp_->intersection(cp_.get()).get(), static_cast<const Geometry*>(cp_.get()));
+    ensure(cp_->symDifference(cp_.get())->isEmpty());
 
     // Distance
     ensure_equals(cp_->distance(cp_.get()), 0);
diff --git a/tests/unit/geom/MultiCurveTest.cpp b/tests/unit/geom/MultiCurveTest.cpp
index 70b0ada4d..9973b5177 100644
--- a/tests/unit/geom/MultiCurveTest.cpp
+++ b/tests/unit/geom/MultiCurveTest.cpp
@@ -153,10 +153,11 @@ void object::test<3>()
 
     // Overlay
     ensure_THROW(mc_->Union(), geos::util::UnsupportedOperationException);
-    ensure_THROW(mc_->Union(mc_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(mc_->difference(mc_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(mc_->intersection(mc_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(mc_->symDifference(mc_.get()), geos::util::UnsupportedOperationException);
+    // TODO: Prevent overlay from degrading CompoundCurve into MultiCurve
+    //ensure_equals_geometry(mc_->Union(mc_.get()).get(), static_cast<const Geometry*>(mc_.get()));
+    ensure(mc_->difference(mc_.get())->isEmpty());
+    //ensure_equals_geometry(mc_->intersection(mc_.get()).get(), static_cast<const Geometry*>(mc_.get()));
+    ensure(mc_->symDifference(mc_.get())->isEmpty());
 
     // Distance
     ensure_equals(mc_->distance(mc_.get()), 0);
diff --git a/tests/unit/geom/MultiSurfaceTest.cpp b/tests/unit/geom/MultiSurfaceTest.cpp
index f12fb9e38..9ee1cc244 100644
--- a/tests/unit/geom/MultiSurfaceTest.cpp
+++ b/tests/unit/geom/MultiSurfaceTest.cpp
@@ -142,10 +142,10 @@ void object::test<3>()
 
     // Overlay
     ensure_THROW(ms_->Union(), geos::util::UnsupportedOperationException);
-    ensure_THROW(ms_->Union(ms_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(ms_->difference(ms_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(ms_->intersection(ms_.get()), geos::util::UnsupportedOperationException);
-    ensure_THROW(ms_->symDifference(ms_.get()), geos::util::UnsupportedOperationException);
+    ensure_equals_geometry(ms_->Union(ms_.get()).get(), static_cast<const Geometry*>(ms_.get()));
+    ensure(ms_->difference(ms_.get())->isEmpty());
+    ensure_equals_geometry(ms_->intersection(ms_.get()).get(), static_cast<const Geometry*>(ms_.get()));
+    ensure(ms_->symDifference(ms_.get())->isEmpty());
 
     // Distance
     ensure_equals(ms_->distance(ms_.get()), 0);
diff --git a/tests/unit/operation/overlayng/OverlayNGTest.cpp b/tests/unit/operation/overlayng/OverlayNGTest.cpp
index 92f1d32a1..d7077e57a 100644
--- a/tests/unit/operation/overlayng/OverlayNGTest.cpp
+++ b/tests/unit/operation/overlayng/OverlayNGTest.cpp
@@ -51,20 +51,8 @@ struct test_overlayng_data {
         std::unique_ptr<Geometry> geom_expected = r.read(expected);
 
 
-        std::unique_ptr<Geometry> geom_result;
-        if (geom_a->hasCurvedComponents() || geom_b->hasCurvedComponents()) {
-            SimpleNoder noder;
-            geos::algorithm::CircularArcIntersector cai;
-            ArcIntersectionAdder aia(cai);
+        auto geom_result = OverlayNG::overlay(geom_a.get(), geom_b.get(), opCode, pm.get());
 
-            noder.setArcIntersector(aia);
-            OverlayNG ong(geom_a.get(), geom_b.get(), pm.get(), opCode);
-            ong.setNoder(&noder);
-
-            geom_result = ong.getResult();
-        } else {
-            geom_result = OverlayNG::overlay(geom_a.get(), geom_b.get(), opCode, pm.get());
-        }
         //std::string wkt_result = w.write(geom_result.get());
         //std::cout << std::endl << wkt_result << std::endl;
         ensure_equals_geometry_xyzm(geom_result.get(), geom_expected.get(), tol);

commit 095c72709ea5043b4a1433d2adb3611410564cd3
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri Mar 27 11:31:49 2026 -0400

    OverlayNG: Support curved types

diff --git a/include/geos/algorithm/PointLocator.h b/include/geos/algorithm/PointLocator.h
index be504c2b0..c249fdc42 100644
--- a/include/geos/algorithm/PointLocator.h
+++ b/include/geos/algorithm/PointLocator.h
@@ -25,6 +25,8 @@
 // Forward declarations
 namespace geos {
 namespace geom {
+class CircularString;
+class CompoundCurve;
 class CoordinateXY;
 class Curve;
 class Geometry;
@@ -98,6 +100,10 @@ private:
 
     geom::Location locate(const geom::CoordinateXY& p, const geom::LineString* l);
 
+    geom::Location locate(const geom::CoordinateXY& p, const geom::CircularString* cs);
+
+    geom::Location locate(const geom::CoordinateXY& p, const geom::CompoundCurve* cs);
+
     static geom::Location locateInPolygonRing(const geom::CoordinateXY& p, const geom::Curve* ring);
 
     static geom::Location locate(const geom::CoordinateXY& p, const geom::Surface* poly);
diff --git a/include/geos/geom/Curve.h b/include/geos/geom/Curve.h
index 1bb16df37..8f30900f2 100644
--- a/include/geos/geom/Curve.h
+++ b/include/geos/geom/Curve.h
@@ -81,6 +81,8 @@ public:
 
     virtual const SimpleCurve* getCurveN(std::size_t) const = 0;
 
+    std::unique_ptr<Curve> clone() const;
+
     std::unique_ptr<Curve> reverse() const;
 
 protected:
diff --git a/include/geos/operation/overlayng/Edge.h b/include/geos/operation/overlayng/Edge.h
index 7ec26eb16..83f67dc6a 100644
--- a/include/geos/operation/overlayng/Edge.h
+++ b/include/geos/operation/overlayng/Edge.h
@@ -184,18 +184,6 @@ private:
 
 public:
 
-#if 0
-    Edge()
-        : aDim(OverlayLabel::DIM_UNKNOWN)
-        , aDepthDelta(0)
-        , aIsHole(false)
-        , bDim(OverlayLabel::DIM_UNKNOWN)
-        , bDepthDelta(0)
-        , bIsHole(false)
-        , pts(nullptr)
-        {};
-#endif
-
     Edge(const std::shared_ptr<const geom::CoordinateSequence>& p_pts, const EdgeSourceInfo* info, bool isCurved);
 
     friend std::ostream& operator<<(std::ostream& os, const Edge& e);
diff --git a/include/geos/operation/overlayng/LineBuilder.h b/include/geos/operation/overlayng/LineBuilder.h
index 2abeda3be..9256f8751 100644
--- a/include/geos/operation/overlayng/LineBuilder.h
+++ b/include/geos/operation/overlayng/LineBuilder.h
@@ -77,7 +77,7 @@ private:
     const geom::GeometryFactory* geometryFactory;
     bool hasResultArea;
     int8_t inputAreaIndex;
-    std::vector<std::unique_ptr<geom::LineString>> lines;
+    std::vector<std::unique_ptr<geom::Curve>> lines;
 
     /**
     * Indicates whether intersections are allowed to produce
@@ -121,7 +121,7 @@ private:
     void addResultLines();
     void addResultLinesMerged();
 
-    std::unique_ptr<geom::LineString> toLine(OverlayEdge* edge) const;
+    std::unique_ptr<geom::Curve> toLine(OverlayEdge* edge) const;
 
     void addResultLinesForNodes();
 
@@ -143,7 +143,7 @@ private:
     * E.g. using the direction of the majority of segments,
     * or preferring the direction of the A edges.)
     */
-    std::unique_ptr<geom::LineString> buildLine(OverlayEdge* node);
+    std::unique_ptr<geom::Curve> buildLine(OverlayEdge* node) const;
 
     /*
     * Finds the next edge around a node which forms
@@ -173,7 +173,7 @@ public:
     LineBuilder(const LineBuilder&) = delete;
     LineBuilder& operator=(const LineBuilder&) = delete;
 
-    std::vector<std::unique_ptr<geom::LineString>> getLines();
+    std::vector<std::unique_ptr<geom::Curve>> getLines();
 
     void setStrictMode(bool p_isStrictResultMode)
     {
diff --git a/include/geos/operation/overlayng/OverlayEdge.h b/include/geos/operation/overlayng/OverlayEdge.h
index 7ad5bdf9e..85dc54fb2 100644
--- a/include/geos/operation/overlayng/OverlayEdge.h
+++ b/include/geos/operation/overlayng/OverlayEdge.h
@@ -61,6 +61,7 @@ private:
     * The label must be interpreted accordingly.
     */
     bool direction;
+    bool m_isCurved;
     CoordinateXY dirPt;
     OverlayLabel* label;
     bool m_isInResultArea;
@@ -81,10 +82,12 @@ public:
 
     OverlayEdge(const CoordinateXYZM& p_orig, const CoordinateXY& p_dirPt,
                 bool p_direction, OverlayLabel* p_label,
-                const std::shared_ptr<const CoordinateSequence>& p_pts)
+                const std::shared_ptr<const CoordinateSequence>& p_pts,
+                bool isCurved)
         : HalfEdge(p_orig)
         , pts(p_pts)
         , direction(p_direction)
+        , m_isCurved(isCurved)
         , dirPt(p_dirPt)
         , label(p_label)
         , m_isInResultArea(false)
@@ -103,6 +106,11 @@ public:
         return direction;
     };
 
+    bool isCurved() const
+    {
+        return m_isCurved;
+    }
+
     const CoordinateXY& directionPt() const override
     {
         return dirPt;
diff --git a/include/geos/operation/overlayng/OverlayEdgeRing.h b/include/geos/operation/overlayng/OverlayEdgeRing.h
index f0e94445a..c3472c15e 100644
--- a/include/geos/operation/overlayng/OverlayEdgeRing.h
+++ b/include/geos/operation/overlayng/OverlayEdgeRing.h
@@ -30,9 +30,9 @@ namespace geom {
 class Coordinate;
 class CoordinateXY;
 class CoordinateSequence;
+class Curve;
 class GeometryFactory;
-class LinearRing;
-class Polygon;
+class Surface;
 }
 namespace operation {
 namespace overlayng {
@@ -50,8 +50,8 @@ class GEOS_DLL OverlayEdgeRing {
     using CoordinateXY = geos::geom::CoordinateXY;
     using CoordinateSequence = geos::geom::CoordinateSequence;
     using GeometryFactory = geos::geom::GeometryFactory;
-    using LinearRing = geos::geom::LinearRing;
-    using Polygon = geos::geom::Polygon;
+    using Curve = geos::geom::Curve;
+    using Surface = geos::geom::Surface;
     using PointOnGeometryLocator = algorithm::locate::PointOnGeometryLocator;
     using IndexedPointInAreaLocator = algorithm::locate::IndexedPointInAreaLocator;
 
@@ -59,23 +59,22 @@ private:
 
     // Members
     OverlayEdge* startEdge;
-    std::unique_ptr<LinearRing> ring;
+    std::unique_ptr<Curve> ring;
     bool m_isHole;
-    mutable std::unique_ptr<IndexedPointInAreaLocator> locator;
+    mutable std::unique_ptr<PointOnGeometryLocator> locator;
     OverlayEdgeRing* shell;
     // a list of EdgeRings which are holes in this EdgeRing
     std::vector<OverlayEdgeRing*> holes;
 
     // Methods
-    void computeRingPts(OverlayEdge* start, CoordinateSequence& pts);
-    void computeRing(const std::shared_ptr<CoordinateSequence> & ringPts, const GeometryFactory* geometryFactory);
+    void computeRing(OverlayEdge* start, const GeometryFactory* geometryFactory);
+    std::unique_ptr<Curve> computeRingGeometry(OverlayEdge* start, const GeometryFactory* geometryFactory) const;
 
     /**
     * Computes the list of coordinates which are contained in this ring.
     * The coordinates are computed once only and cached.
     * @return an array of the {@link Coordinate}s in this ring
     */
-    const CoordinateSequence& getCoordinates() const;
     PointOnGeometryLocator* getLocator() const;
     static void closeRing(CoordinateSequence& pts);
     bool contains(const OverlayEdgeRing& otherRing) const;
@@ -86,8 +85,8 @@ public:
 
     OverlayEdgeRing(OverlayEdge* start, const GeometryFactory* geometryFactory);
 
-    std::unique_ptr<LinearRing> getRing();
-    const LinearRing* getRingPtr() const;
+    std::unique_ptr<Curve> getRing();
+    const Curve* getRingPtr() const;
 
     const geom::Envelope& getEnvelope() const;
 
@@ -128,7 +127,7 @@ public:
     * Computes the {@link Polygon} formed by this ring and any contained holes.
     * @return the {@link Polygon} formed by this ring and its holes.
     */
-    std::unique_ptr<Polygon> toPolygon(const GeometryFactory* factory);
+    std::unique_ptr<Surface> toSurface(const GeometryFactory* factory);
 
     OverlayEdge* getEdge();
 
diff --git a/include/geos/operation/overlayng/OverlayGraph.h b/include/geos/operation/overlayng/OverlayGraph.h
index eda4d07ed..85a46d97a 100644
--- a/include/geos/operation/overlayng/OverlayGraph.h
+++ b/include/geos/operation/overlayng/OverlayGraph.h
@@ -70,13 +70,13 @@ private:
     * Create and add HalfEdge pairs to map and vector containers,
     * using local std::deque storage for objects.
     */
-    OverlayEdge* createEdgePair(const std::shared_ptr<const CoordinateSequence> &pts, OverlayLabel *lbl);
+    OverlayEdge* createEdgePair(const std::shared_ptr<const CoordinateSequence> &pts, OverlayLabel *lbl, bool isCurved);
 
     /**
     * Create a single OverlayEdge in local std::deque storage, and return the
     * pointer.
     */
-    OverlayEdge* createOverlayEdge(const std::shared_ptr<const CoordinateSequence> &pts, OverlayLabel *lbl, bool direction);
+    OverlayEdge* createOverlayEdge(const std::shared_ptr<const CoordinateSequence> &pts, OverlayLabel *lbl, bool direction, bool isCurved);
 
     void insert(OverlayEdge* e);
 
diff --git a/include/geos/operation/overlayng/OverlayMixedPoints.h b/include/geos/operation/overlayng/OverlayMixedPoints.h
index c7b681228..21907ad74 100644
--- a/include/geos/operation/overlayng/OverlayMixedPoints.h
+++ b/include/geos/operation/overlayng/OverlayMixedPoints.h
@@ -40,6 +40,9 @@ namespace locate {
 class PointOnGeometryLocator;
 }
 }
+namespace noding {
+class Noder;
+}
 }
 
 namespace geos {      // geos.
@@ -74,6 +77,7 @@ namespace overlayng { // geos.operation.overlayng
  * @author Martin Davis
  */
 class GEOS_DLL OverlayMixedPoints {
+    using Curve = geos::geom::Curve;
     using GeometryFactory = geos::geom::GeometryFactory;
     using PrecisionModel = geos::geom::PrecisionModel;
     using Geometry = geos::geom::Geometry;
@@ -83,6 +87,8 @@ class GEOS_DLL OverlayMixedPoints {
     using Point = geos::geom::Point;
     using Polygon = geos::geom::Polygon;
     using LineString = geos::geom::LineString;
+    using Noder = geos::noding::Noder;
+    using Surface = geos::geom::Surface;
     using PointOnGeometryLocator = algorithm::locate::PointOnGeometryLocator;
 
 private:
@@ -94,6 +100,7 @@ private:
     const Geometry* geomNonPointInput;
     const GeometryFactory* geometryFactory;
     bool isPointRHS;
+    Noder* noder;
 
     std::unique_ptr<Geometry> geomNonPoint;
     int geomNonPointDim;
@@ -121,19 +128,19 @@ private:
 
     std::unique_ptr<Geometry> copyNonPoint() const;
 
-    std::unique_ptr<CoordinateSequence> extractCoordinates(const Geometry* points, const PrecisionModel* pm) const;
+    static std::unique_ptr<CoordinateSequence> extractCoordinates(const Geometry* points, const PrecisionModel* pm);
 
-    std::vector<std::unique_ptr<Polygon>> extractPolygons(const Geometry* geom) const;
+    static std::vector<std::unique_ptr<Surface>> extractPolygons(const Geometry* geom);
 
-    std::vector<std::unique_ptr<LineString>> extractLines(const Geometry* geom) const;
+    static std::vector<std::unique_ptr<Curve>> extractLines(const Geometry* geom);
 
 
 
 public:
 
-    OverlayMixedPoints(int p_opCode, const Geometry* geom0, const Geometry* geom1, const PrecisionModel* p_pm);
+    OverlayMixedPoints(int p_opCode, const Geometry* geom0, const Geometry* geom1, const PrecisionModel* p_pm, Noder* p_noder);
 
-    static std::unique_ptr<Geometry> overlay(int opCode, const Geometry* geom0, const Geometry* geom1, const PrecisionModel* pm);
+    static std::unique_ptr<Geometry> overlay(int opCode, const Geometry* geom0, const Geometry* geom1, const PrecisionModel* pm, Noder* p_noder);
 
     std::unique_ptr<Geometry> getResult();
 
diff --git a/include/geos/operation/overlayng/OverlayUtil.h b/include/geos/operation/overlayng/OverlayUtil.h
index 6bff9c358..25fa99312 100644
--- a/include/geos/operation/overlayng/OverlayUtil.h
+++ b/include/geos/operation/overlayng/OverlayUtil.h
@@ -14,10 +14,10 @@
 
 #pragma once
 
-#include <geos/geom/Point.h>
-#include <geos/geom/Polygon.h>
-#include <geos/geom/LineString.h>
+#include <geos/geom/Curve.h>
 #include <geos/geom/Geometry.h>
+#include <geos/geom/Point.h>
+#include <geos/geom/Surface.h>
 
 #include <geos/export.h>
 
@@ -55,10 +55,10 @@ class GEOS_DLL OverlayUtil {
     using Geometry = geos::geom::Geometry;
     using Coordinate = geos::geom::Coordinate;
     using CoordinateSequence = geos::geom::CoordinateSequence;
+    using Curve = geos::geom::Curve;
     using Envelope = geos::geom::Envelope;
     using Point = geos::geom::Point;
-    using LineString = geos::geom::LineString;
-    using Polygon = geos::geom::Polygon;
+    using Surface = geos::geom::Surface;
     using GeometryFactory = geos::geom::GeometryFactory;
     using PrecisionModel = geos::geom::PrecisionModel;
 
@@ -172,8 +172,8 @@ public:
     * Creates an overlay result geometry for homogeneous or mixed components.
     */
     static std::unique_ptr<Geometry> createResultGeometry(
-        std::vector<std::unique_ptr<Polygon>>& resultPolyList,
-        std::vector<std::unique_ptr<LineString>>& resultLineList,
+        std::vector<std::unique_ptr<Surface>>& resultPolyList,
+        std::vector<std::unique_ptr<Curve>>& resultLineList,
         std::vector<std::unique_ptr<Point>>& resultPointList,
         const GeometryFactory* geometryFactory);
 
diff --git a/include/geos/operation/overlayng/PolygonBuilder.h b/include/geos/operation/overlayng/PolygonBuilder.h
index 9e820fc14..f30b43226 100644
--- a/include/geos/operation/overlayng/PolygonBuilder.h
+++ b/include/geos/operation/overlayng/PolygonBuilder.h
@@ -29,7 +29,7 @@ namespace geos {
 namespace geom {
 class GeometryFactory;
 class Geometry;
-class Polygon;
+class Surface;
 }
 namespace operation {
 namespace overlayng {
@@ -55,7 +55,7 @@ private:
     // Storage
     std::vector<std::unique_ptr<OverlayEdgeRing>> vecOER;
 
-    std::vector<std::unique_ptr<geom::Polygon>> computePolygons(const std::vector<OverlayEdgeRing*>& shellList) const;
+    std::vector<std::unique_ptr<geom::Surface>> computePolygons(const std::vector<OverlayEdgeRing*>& shellList) const;
 
     void buildRings(const std::vector<OverlayEdge*>& resultAreaEdges);
 
@@ -138,7 +138,7 @@ public:
     PolygonBuilder& operator=(const PolygonBuilder&) = delete;
 
     // Methods
-    std::vector<std::unique_ptr<geom::Polygon>> getPolygons() const;
+    std::vector<std::unique_ptr<geom::Surface>> getPolygons() const;
     std::vector<OverlayEdgeRing*> getShellRings() const;
 
 
diff --git a/src/algorithm/PointLocator.cpp b/src/algorithm/PointLocator.cpp
index 5545d7655..abcee3e12 100644
--- a/src/algorithm/PointLocator.cpp
+++ b/src/algorithm/PointLocator.cpp
@@ -19,6 +19,8 @@
 
 #include <geos/algorithm/PointLocator.h>
 #include <geos/algorithm/PointLocation.h>
+#include <geos/geom/CircularString.h>
+#include <geos/geom/CompoundCurve.h>
 #include <geos/geom/Geometry.h>
 #include <geos/geom/Point.h>
 #include <geos/geom/LineString.h>
@@ -31,7 +33,6 @@
 #include <geos/util/UnsupportedOperationException.h>
 
 #include <cassert>
-#include <typeinfo>
 
 using namespace geos::geom;
 
@@ -97,6 +98,16 @@ PointLocator::computeLocation(const CoordinateXY& p, const Geometry* geom)
             updateLocationInfo(locate(p, ls));
             break;
         }
+        case GEOS_CIRCULARSTRING: {
+            const CircularString* cs = static_cast<const CircularString*>(geom);
+            updateLocationInfo(locate(p, cs));
+            break;
+        }
+        case GEOS_COMPOUNDCURVE: {
+            const CompoundCurve* cc = static_cast<const CompoundCurve*>(geom);
+            updateLocationInfo(locate(p, cc));
+            break;
+        }
         case GEOS_POLYGON: {
             const Polygon* po = static_cast<const Polygon*>(geom);
             updateLocationInfo(locate(p, po));
@@ -183,6 +194,73 @@ PointLocator::locate(const CoordinateXY& p, const LineString* l)
     return Location::EXTERIOR;
 }
 
+/* private */
+Location
+PointLocator::locate(const CoordinateXY& p, const CircularString* cs)
+{
+    if(!cs->getEnvelopeInternal()->intersects(p)) {
+        return Location::EXTERIOR;
+    }
+
+    if (cs->isClosed()) {
+        const CoordinateSequence* seq = cs->getCoordinatesRO();
+        if (p.equals2D(seq->front<CoordinateXY>())) {
+            return Location::BOUNDARY;
+        }
+        if (p.equals2D(seq->back<CoordinateXY>())) {
+            return Location::BOUNDARY;
+        }
+    }
+
+    for (const auto& arc : cs->getArcs()) {
+        if (arc.containsPoint(p)) {
+            return Location::INTERIOR;
+        }
+    }
+
+    return Location::EXTERIOR;
+}
+
+/* private */
+Location
+PointLocator::locate(const CoordinateXY& p, const CompoundCurve* cc)
+{
+    if(!cc->getEnvelopeInternal()->intersects(p)) {
+        return Location::EXTERIOR;
+    }
+
+    if (cc->isClosed()) {
+        const SimpleCurve* firstCurve = cc->getCurveN(0);
+        if (p.equals2D(firstCurve->getCoordinatesRO()->front<CoordinateXY>())) {
+            return Location::BOUNDARY;
+        }
+
+        const SimpleCurve* lastCurve = cc->getCurveN(cc->getNumCurves() - 1);
+        if (p.equals2D(lastCurve->getCoordinatesRO()->back<CoordinateXY>())) {
+            return Location::BOUNDARY;
+        }
+    }
+
+    for (std::size_t i = 0; i < cc->getNumCurves(); i++) {
+        const SimpleCurve* curve = cc->getCurveN(i);
+        if (curve->getGeometryTypeId() == GEOS_CIRCULARSTRING) {
+            const CircularString* cs = static_cast<const CircularString*>(curve);
+            for (const auto& arc : cs->getArcs()) {
+                if (arc.containsPoint(p)) {
+                    return Location::INTERIOR;
+                }
+            }
+        } else {
+            const CoordinateSequence* seq = curve->getCoordinatesRO();
+            if(PointLocation::isOnLine(p, seq)) {
+                return Location::INTERIOR;
+            }
+        }
+    }
+
+    return Location::EXTERIOR;
+}
+
 /* private */
 Location
 PointLocator::locateInPolygonRing(const CoordinateXY& p, const Curve* ring)
diff --git a/src/geom/Curve.cpp b/src/geom/Curve.cpp
index a55678267..26b7dc533 100644
--- a/src/geom/Curve.cpp
+++ b/src/geom/Curve.cpp
@@ -48,6 +48,12 @@ Curve::apply_rw(GeometryFilter* filter)
     filter->filter_rw(this);
 }
 
+std::unique_ptr<Curve>
+Curve::clone() const
+{
+    return std::unique_ptr<Curve>(static_cast<Curve*>(Geometry::clone().release()));
+}
+
 bool
 Curve::isRing() const
 {
diff --git a/src/geom/GeometryFactory.cpp b/src/geom/GeometryFactory.cpp
index f53012a4c..cc5e97870 100644
--- a/src/geom/GeometryFactory.cpp
+++ b/src/geom/GeometryFactory.cpp
@@ -642,6 +642,13 @@ const
     return std::unique_ptr<CurvePolygon>(new CurvePolygon(std::move(shell), std::move(holes), *this));
 }
 
+static std::unique_ptr<LineString>
+linearRingToLineString(std::unique_ptr<Curve> linearRing)
+{
+    const std::shared_ptr<const CoordinateSequence> pts = detail::down_cast<const SimpleCurve*>(linearRing.get())->getSharedCoordinates();
+    return linearRing->getFactory()->createLineString(pts);
+}
+
 /* public */
 std::unique_ptr<Surface>
 GeometryFactory::createSurface(std::unique_ptr<Curve> && shell)
@@ -652,6 +659,10 @@ const
         return createPolygon(std::move(shellLR));
     }
 
+    if (shell->getGeometryTypeId() == GEOS_LINEARRING) {
+        shell = linearRingToLineString(std::move(shell));
+    }
+
     return createCurvePolygon(std::move(shell));
 }
 
@@ -675,6 +686,17 @@ const
         return createPolygon(std::move(shellLR), std::move(holesLR));
     }
 
+    // Purge LinearRings
+    if (shell->getGeometryTypeId() == GEOS_LINEARRING) {
+        shell = linearRingToLineString(std::move(shell));
+    }
+
+    for (std::size_t i = 0; i < holes.size(); i++) {
+        if (holes[i]->getGeometryTypeId() == GEOS_LINEARRING) {
+            holes[i] = linearRingToLineString(std::move(holes[i]));
+        }
+    }
+
     return createCurvePolygon(std::move(shell), std::move(holes));
 }
 
diff --git a/src/noding/snap/SnappingNoder.cpp b/src/noding/snap/SnappingNoder.cpp
index f4848d1fc..e2f0643d6 100644
--- a/src/noding/snap/SnappingNoder.cpp
+++ b/src/noding/snap/SnappingNoder.cpp
@@ -111,9 +111,8 @@ SnappingNoder::snap(const CoordinateSequence *cs)
     snapCoords->reserve(cs->size());
 
     cs->forEach<Coordinate>([&snapCoords, this](const Coordinate& origPt) {
-        const Coordinate& pt = snapIndex.snap(origPt);
+        const Coordinate& pt = origPt.isValid() ? snapIndex.snap(origPt) : origPt;
         snapCoords->add(pt, false); // Remove repeated points
-
     });
     return snapCoords;
 }
diff --git a/src/operation/overlayng/IndexedPointOnLineLocator.cpp b/src/operation/overlayng/IndexedPointOnLineLocator.cpp
index 95a7e12da..b521145cb 100644
--- a/src/operation/overlayng/IndexedPointOnLineLocator.cpp
+++ b/src/operation/overlayng/IndexedPointOnLineLocator.cpp
@@ -29,7 +29,7 @@ namespace overlayng { // geos.operation.overlayng
 /*public*/
 geom::Location
 IndexedPointOnLineLocator::locate(const geom::CoordinateXY* p) {
-    // TODO: optimize this with a segment index
+    // TODO: optimize this with a segment/arc index
     algorithm::PointLocator locator;
     return locator.locate(*p, &inputGeom);
 }
diff --git a/src/operation/overlayng/InputGeometry.cpp b/src/operation/overlayng/InputGeometry.cpp
index 6c3c5a2ba..320d887f0 100644
--- a/src/operation/overlayng/InputGeometry.cpp
+++ b/src/operation/overlayng/InputGeometry.cpp
@@ -13,6 +13,7 @@
  **********************************************************************/
 
 #include <geos/operation/overlayng/InputGeometry.h>
+#include <geos/algorithm/locate/SimplePointInAreaLocator.h>
 
 namespace geos {      // geos
 namespace operation { // geos.operation
@@ -21,6 +22,7 @@ namespace overlayng { // geos.operation.overlayng
 using geos::geom::Location;
 using geos::geom::Geometry;
 using geos::geom::Envelope;
+using geos::algorithm::locate::SimplePointInAreaLocator;
 using geos::algorithm::locate::IndexedPointInAreaLocator;
 using geos::algorithm::locate::PointOnGeometryLocator;
 
@@ -166,13 +168,23 @@ PointOnGeometryLocator*
 InputGeometry::getLocator(uint8_t geomIndex)
 {
     if (geomIndex == 0) {
-        if (ptLocatorA == nullptr)
-            ptLocatorA.reset(new IndexedPointInAreaLocator(*getGeometry(geomIndex)));
+        if (ptLocatorA == nullptr) {
+            if (geom[0]->hasCurvedComponents()) {
+                ptLocatorA = std::make_unique<SimplePointInAreaLocator>(*getGeometry(geomIndex));
+            } else {
+                ptLocatorA = std::make_unique<IndexedPointInAreaLocator>(*getGeometry(geomIndex));
+            }
+        }
         return ptLocatorA.get();
     }
     else {
-        if (ptLocatorB == nullptr)
-            ptLocatorB.reset(new IndexedPointInAreaLocator(*getGeometry(geomIndex)));
+        if (ptLocatorB == nullptr) {
+            if (geom[1]->hasCurvedComponents()) {
+                ptLocatorB = std::make_unique<SimplePointInAreaLocator>(*getGeometry(geomIndex));
+            } else {
+                ptLocatorB = std::make_unique<IndexedPointInAreaLocator>(*getGeometry(geomIndex));
+            }
+        }
         return ptLocatorB.get();
     }
 }
diff --git a/src/operation/overlayng/LineBuilder.cpp b/src/operation/overlayng/LineBuilder.cpp
index a676b36e5..4d1a25877 100644
--- a/src/operation/overlayng/LineBuilder.cpp
+++ b/src/operation/overlayng/LineBuilder.cpp
@@ -17,8 +17,10 @@
 #include <geos/operation/overlayng/OverlayEdge.h>
 #include <geos/operation/overlayng/OverlayLabel.h>
 #include <geos/operation/overlayng/OverlayNG.h>
+#include <geos/geom/CircularString.h>
 #include <geos/geom/GeometryFactory.h>
 #include <geos/geom/CoordinateSequence.h>
+#include <geos/geom/util/CurveBuilder.h>
 
 
 
@@ -29,7 +31,7 @@ namespace overlayng { // geos.operation.overlayng
 using namespace geos::geom;
 
 /*public*/
-std::vector<std::unique_ptr<LineString>>
+std::vector<std::unique_ptr<Curve>>
 LineBuilder::getLines()
 {
     markResultLines();
@@ -174,19 +176,22 @@ LineBuilder::addResultLines()
     }
 }
 
-std::unique_ptr<LineString>
+std::unique_ptr<Curve>
 LineBuilder::toLine(OverlayEdge* edge) const
 {
     // bool isForward = edge->isForward();
     const auto* edgePts = edge->getCoordinatesRO();
 
-    std::unique_ptr<CoordinateSequence> pts(new CoordinateSequence(0u, edgePts->hasZ(), edgePts->hasM()));
+    auto pts = std::make_unique<CoordinateSequence>(0u, edgePts->hasZ(), edgePts->hasM());
     pts->reserve(edgePts->size());
     pts->add(edge->orig(), false);
     edge->addCoordinates(pts.get());
 
     assert(pts->size() == edgePts->size());
 
+    if (edge->isCurved()) {
+        return geometryFactory->createCircularString(std::move(pts));
+    }
     return geometryFactory->createLineString(std::move(pts));
 }
 
@@ -217,7 +222,7 @@ LineBuilder::addResultLinesForNodes()
         * This will find all lines originating at nodes
         */
         if (degreeOfLines(edge) != 2) {
-            std::unique_ptr<LineString> line = buildLine(edge);
+            auto line = buildLine(edge);
             lines.push_back(std::move(line));
         }
     }
@@ -241,20 +246,24 @@ LineBuilder::addResultLinesRings()
 }
 
 /*private*/
-std::unique_ptr<LineString>
-LineBuilder::buildLine(OverlayEdge* node)
+std::unique_ptr<Curve>
+LineBuilder::buildLine(OverlayEdge* node) const
 {
+    const bool constructZ = node->getCoordinatesRO()->hasZ();
+    const bool constructM = node->getCoordinatesRO()->hasM();
+    geom::util::CurveBuilder cb(*geometryFactory, constructZ, constructM);
+
     // assert: edgeStart degree = 1
     // assert: edgeStart direction = forward
-    std::unique_ptr<CoordinateSequence> pts(new CoordinateSequence());
-    pts->add(node->orig(), false);
+    cb.add(*node->getCoordinatesRO(), node->isCurved());
 
     bool isNodeForward = node->isForward();
 
     OverlayEdge* e = node;
     do {
         e->markVisitedBoth();
-        e->addCoordinates(pts.get());
+        CoordinateSequence& pts = cb.getSeq(e->isCurved());
+        e->addCoordinates(&pts);
 
         // end line if next vertex is a node
         if (degreeOfLines(e->symOE()) != 2) {
@@ -264,12 +273,14 @@ LineBuilder::buildLine(OverlayEdge* node)
         // e will be nullptr if next edge has been visited, which indicates a ring
     }
     while (e != nullptr);
+
     // reverse coordinates before constructing
+    auto geom = cb.getGeometry();
     if(!isNodeForward) {
-        pts->reverse();
+        return geom->reverse();
     }
 
-    return geometryFactory->createLineString(std::move(pts));
+    return geom;
 }
 
 /*private*/
diff --git a/src/operation/overlayng/OverlayEdgeRing.cpp b/src/operation/overlayng/OverlayEdgeRing.cpp
index 1587f9e0c..12f4c8e92 100644
--- a/src/operation/overlayng/OverlayEdgeRing.cpp
+++ b/src/operation/overlayng/OverlayEdgeRing.cpp
@@ -17,11 +17,18 @@
 #include <geos/geom/Location.h>
 #include <geos/geom/Envelope.h>
 #include <geos/geom/Coordinate.h>
+#include <geos/geom/CoordinateFilter.h>
 #include <geos/geom/CoordinateSequence.h>
+#include <geos/geom/CircularString.h>
+#include <geos/geom/CompoundCurve.h>
+#include <geos/geom/CurvePolygon.h>
 #include <geos/geom/GeometryFactory.h>
+#include <geos/geom/util/CurveBuilder.h>
 #include <geos/util/TopologyException.h>
+#include <geos/algorithm/PointLocation.h>
 #include <geos/algorithm/locate/PointOnGeometryLocator.h>
 #include <geos/algorithm/locate/IndexedPointInAreaLocator.h>
+#include <geos/algorithm/locate/SimplePointInAreaLocator.h>
 #include <geos/algorithm/Orientation.h>
 #include <geos/operation/polygonize/EdgeRing.h>
 
@@ -32,8 +39,7 @@ namespace overlayng { // geos.operation.overlayng
 using namespace geos::geom;
 using geos::operation::polygonize::EdgeRing;
 using geos::algorithm::locate::PointOnGeometryLocator;
-
-
+using geos::algorithm::locate::SimplePointInAreaLocator;
 
 OverlayEdgeRing::OverlayEdgeRing(OverlayEdge* start, const GeometryFactory* geometryFactory)
     : startEdge(start)
@@ -42,19 +48,17 @@ OverlayEdgeRing::OverlayEdgeRing(OverlayEdge* start, const GeometryFactory* geom
     , locator(nullptr)
     , shell(nullptr)
 {
-    auto ringPts = std::make_shared<CoordinateSequence>(0u, start->getCoordinatesRO()->hasZ(), start->getCoordinatesRO()->hasM());
-    computeRingPts(start, *ringPts);
-    computeRing(ringPts, geometryFactory);
+    computeRing(start, geometryFactory);
 }
 
 /*public*/
-std::unique_ptr<LinearRing>
+std::unique_ptr<Curve>
 OverlayEdgeRing::getRing()
 {
     return std::move(ring);
 }
 
-const LinearRing*
+const Curve*
 OverlayEdgeRing::getRingPtr() const
 {
     return ring.get();
@@ -133,46 +137,49 @@ OverlayEdgeRing::closeRing(CoordinateSequence& pts)
 }
 
 /*private*/
-void
-OverlayEdgeRing::computeRingPts(OverlayEdge* start, CoordinateSequence& pts)
+std::unique_ptr<Curve>
+OverlayEdgeRing::computeRingGeometry(OverlayEdge* start, const GeometryFactory* gfact) const
 {
     OverlayEdge* edge = start;
+
+    const bool hasZ = start->getCoordinatesRO()->hasZ();
+    const bool hasM = start->getCoordinatesRO()->hasM();
+
+    geom::util::CurveBuilder cb(*gfact, hasZ, hasM);
+
     do {
         if (edge->getEdgeRing() == this)
-            throw util::TopologyException("Edge visited twice during ring-building", edge->getCoordinate());
+            throw geos::util::TopologyException("Edge visited twice during ring-building", edge->getCoordinate());
             // only valid for polygonal output
 
+        CoordinateSequence& pts = cb.getSeq(edge->isCurved());
         edge->addCoordinates(&pts);
         edge->setEdgeRing(this);
+
         if (edge->nextResult() == nullptr)
-            throw util::TopologyException("Found null edge in ring", edge->dest());
+            throw geos::util::TopologyException("Found null edge in ring", edge->dest());
 
         edge = edge->nextResult();
     }
     while (edge != start);
-    closeRing(pts);
+
+    cb.closeRing();
+    return cb.getGeometry();
 }
 
 /*private*/
 void
-OverlayEdgeRing::computeRing(const std::shared_ptr<CoordinateSequence> & p_ringPts, const GeometryFactory* geometryFactory)
+OverlayEdgeRing::computeRing(OverlayEdge* start, const GeometryFactory* geometryFactory)
 {
     if (ring != nullptr) return;   // don't compute more than once
-    ring = geometryFactory->createLinearRing(p_ringPts);
-    m_isHole = algorithm::Orientation::isCCW(ring->getCoordinatesRO());
-}
+    ring = computeRingGeometry(start, geometryFactory);
 
-/**
-* Computes the list of coordinates which are contained in this ring.
-* The coordinates are computed once only and cached.
-*
-* @return an array of the {@link Coordinate}s in this ring
-*/
-/*private*/
-const CoordinateSequence&
-OverlayEdgeRing::getCoordinates() const
-{
-    return *ring->getCoordinatesRO();
+    if (ring->getGeometryTypeId() == GEOS_COMPOUNDCURVE) {
+        const auto seq = ring->getCoordinates();
+        m_isHole = algorithm::Orientation::isCCW(seq.get());
+    } else {
+        m_isHole = algorithm::Orientation::isCCW(static_cast<const SimpleCurve*>(ring.get())->getCoordinatesRO());
+    }
 }
 
 /**
@@ -209,12 +216,33 @@ OverlayEdgeRing::findEdgeRingContaining(const std::vector<OverlayEdgeRing*>& erL
     return minContainingRing;
 }
 
+// Adapter class to check whether a point lies within a ring.
+// Unlike IndexedPointInAreaLocator, SimplePointInAreaLocator does not treat
+// closed rings as areas.
+class PointInCurvedRingLocator : public algorithm::locate::PointOnGeometryLocator {
+public:
+    explicit PointInCurvedRingLocator(const Curve& ring) : m_ring(ring) {}
+
+    geom::Location locate(const geom::CoordinateXY* p) override {
+        return algorithm::PointLocation::locateInRing(*p, m_ring);
+    }
+
+private:
+    const Curve& m_ring;
+};
+
 /*private*/
 PointOnGeometryLocator*
 OverlayEdgeRing::getLocator() const
 {
     if (locator == nullptr) {
-      locator.reset(new IndexedPointInAreaLocator(*(getRingPtr())));
+        const Curve* p_ring = getRingPtr();
+        if (p_ring->hasCurvedComponents()) {
+            locator = detail::make_unique<PointInCurvedRingLocator>(*p_ring);
+        } else {
+            locator = detail::make_unique<IndexedPointInAreaLocator>(*p_ring);
+        }
+
     }
     return locator.get();
 }
@@ -252,24 +280,51 @@ OverlayEdgeRing::contains(const OverlayEdgeRing& otherRing) const {
 bool
 OverlayEdgeRing::isPointInOrOut(const OverlayEdgeRing& otherRing) const {
     // in most cases only one or two points will be checked
-    for (const CoordinateXY& pt : otherRing.getCoordinates().items<CoordinateXY>()) {
-        geom::Location loc = locate(pt);
-        if (loc == geom::Location::INTERIOR) {
-            return true;
+
+    struct PointTester : public geom::CoordinateFilter {
+
+    public:
+        explicit PointTester(const OverlayEdgeRing* p_ring) : m_er(p_ring), m_result(false) {}
+
+        void filter_ro(const CoordinateXY* pt) override {
+            Location loc = m_er->locate(*pt);
+
+            if (loc == geom::Location::INTERIOR) {
+                m_done = true;
+                m_result = true;
+            } else if (loc == geom::Location::EXTERIOR) {
+                m_done = true;
+                m_result = false;
+            }
+
+            // pt is on BOUNDARY, so keep checking for a determining location
         }
-        if (loc == geom::Location::EXTERIOR) {
-            return false;
+
+        bool isDone() const override {
+            return m_done;
         }
-        // pt is on BOUNDARY, so keep checking for a determining location
-    }
-    return false;
+
+        bool getResult() const {
+            return m_result;
+        }
+
+    private:
+        const OverlayEdgeRing* m_er;
+        bool m_done{false};
+        bool m_result;
+    };
+
+    PointTester tester(this);
+    otherRing.getRingPtr()->apply_ro(&tester);
+
+    return tester.getResult();
 }
 
 /*public*/
 const Coordinate&
 OverlayEdgeRing::getCoordinate() const
 {
-    return ring->getCoordinatesRO()->getAt(0);
+    return *detail::down_cast<const Coordinate*>(ring->getCoordinate());
 }
 
 /**
@@ -277,20 +332,19 @@ OverlayEdgeRing::getCoordinate() const
 * @return the {@link Polygon} formed by this ring and its holes.
 */
 /*public*/
-std::unique_ptr<Polygon>
-OverlayEdgeRing::toPolygon(const GeometryFactory* factory)
+std::unique_ptr<Surface>
+OverlayEdgeRing::toSurface(const GeometryFactory* factory)
 {
     if (holes.empty()) {
-        return factory->createPolygon(std::move(ring));
-    } else {
-        std::vector<std::unique_ptr<LinearRing>> holeLR(holes.size());
-
-        for (std::size_t i = 0; i < holes.size(); i++) {
-            holeLR[i] = holes[i]->getRing();
-        }
-
-        return factory->createPolygon(std::move(ring), std::move(holeLR));
+        return factory->createSurface(std::move(ring));
     }
+
+    std::vector<std::unique_ptr<Curve>> holeCurves(holes.size());
+    for (std::size_t i = 0; i < holes.size(); i++) {
+        holeCurves[i] = holes[i]->getRing();
+    }
+
+    return factory->createSurface(std::move(ring), std::move(holeCurves));
 }
 
 /*public*/
diff --git a/src/operation/overlayng/OverlayGraph.cpp b/src/operation/overlayng/OverlayGraph.cpp
index a58983e21..7fd39fefd 100644
--- a/src/operation/overlayng/OverlayGraph.cpp
+++ b/src/operation/overlayng/OverlayGraph.cpp
@@ -14,9 +14,11 @@
 
 #include <geos/operation/overlayng/OverlayGraph.h>
 
+#include <geos/algorithm/CircularArcs.h>
 #include <geos/operation/overlayng/Edge.h>
 #include <geos/geom/Coordinate.h>
 #include <geos/geom/CoordinateSequence.h>
+#include <geos/geom/CircularArc.h>
 
 #ifndef GEOS_DEBUG
 #define GEOS_DEBUG 0
@@ -84,7 +86,7 @@ OverlayGraph::addEdge(Edge* edge)
 {
     // CoordinateSequence* pts = = edge->getCoordinates().release();
     std::shared_ptr<const CoordinateSequence> pts = edge->releaseCoordinates();
-    OverlayEdge* e = createEdgePair(pts, createOverlayLabel(edge));
+    OverlayEdge* e = createEdgePair(pts, createOverlayLabel(edge), edge->isCurved());
 #if GEOS_DEBUG
     std::cerr << "added edge: " << *e << std::endl;
 #endif
@@ -95,32 +97,52 @@ OverlayGraph::addEdge(Edge* edge)
 
 /*private*/
 OverlayEdge*
-OverlayGraph::createEdgePair(const std::shared_ptr<const CoordinateSequence>& pts, OverlayLabel *lbl)
+OverlayGraph::createEdgePair(const std::shared_ptr<const CoordinateSequence>& pts, OverlayLabel *lbl, bool isCurved)
 {
-    OverlayEdge* e0 = createOverlayEdge(pts, lbl, true);
-    OverlayEdge* e1 = createOverlayEdge(pts, lbl, false);
+    OverlayEdge* e0 = createOverlayEdge(pts, lbl, true, isCurved);
+    OverlayEdge* e1 = createOverlayEdge(pts, lbl, false, isCurved);
     e0->link(e1);
     return e0;
 }
 
+static CoordinateXY
+getDirectionPoint(const CoordinateSequence& pts, bool forward, bool isCurved)
+{
+    if (isCurved) {
+        assert(pts.size() >= 3);
+        if (forward) {
+            CircularArc arc(pts, 0);
+            return arc.getDirectionPoint();
+        } else {
+            CircularArc arc(pts, pts.size() - 3);
+            return algorithm::CircularArcs::getDirectionPoint(arc.getCenter(), arc.getRadius(), arc.theta2(), !arc.isCCW());
+        }
+    }
+
+    assert(pts.size() >= 2);
+    if (forward) {
+        return pts.getAt<CoordinateXY>(1);
+    }
+
+    return pts.getAt<CoordinateXY>(pts.size() - 2);
+}
+
 /*private*/
 OverlayEdge*
-OverlayGraph::createOverlayEdge(const std::shared_ptr<const CoordinateSequence>& pts, OverlayLabel* lbl, bool direction)
+OverlayGraph::createOverlayEdge(const std::shared_ptr<const CoordinateSequence>& pts, OverlayLabel* lbl, bool direction, bool isCurved)
 {
+    assert(pts->size() >= 2);
+
     CoordinateXYZM origin;
-    CoordinateXYZM dirPt;
+    const CoordinateXY dirPt = getDirectionPoint(*pts, direction, isCurved);
 
     if (direction) {
         pts->getAt(0, origin);
-        pts->getAt(1, dirPt);
     }
     else {
-        assert(pts->size() > 0);
-        std::size_t ilast = pts->size() - 1;
-        pts->getAt(ilast, origin);
-        pts->getAt(ilast-1, dirPt);
+        pts->getAt(pts->size() - 1, origin);
     }
-    ovEdgeQue.emplace_back(origin, dirPt, direction, lbl, pts);
+    ovEdgeQue.emplace_back(origin, dirPt, direction, lbl, pts, isCurved);
     OverlayEdge& ove = ovEdgeQue.back();
     return &ove;
 }
diff --git a/src/operation/overlayng/OverlayMixedPoints.cpp b/src/operation/overlayng/OverlayMixedPoints.cpp
index 62492d6b7..d5a0b86e2 100644
--- a/src/operation/overlayng/OverlayMixedPoints.cpp
+++ b/src/operation/overlayng/OverlayMixedPoints.cpp
@@ -16,6 +16,7 @@
 
 #include <geos/algorithm/locate/IndexedPointInAreaLocator.h>
 #include <geos/algorithm/locate/PointOnGeometryLocator.h>
+#include <geos/algorithm/locate/SimplePointInAreaLocator.h>
 #include <geos/geom/CoordinateSequence.h>
 #include <geos/geom/Coordinate.h>
 #include <geos/geom/CoordinateFilter.h>
@@ -38,6 +39,7 @@ namespace overlayng { // geos.operation.overlayng
 using namespace geos::geom;
 using geos::algorithm::locate::PointOnGeometryLocator;
 using geos::algorithm::locate::IndexedPointInAreaLocator;
+using geos::algorithm::locate::SimplePointInAreaLocator;
 
 /**
  * @brief Extracts and rounds coordinates from a geometry
@@ -76,10 +78,11 @@ private:
 };
 
 /*public*/
-OverlayMixedPoints::OverlayMixedPoints(int p_opCode, const Geometry* geom0, const Geometry* geom1, const PrecisionModel* p_pm)
+OverlayMixedPoints::OverlayMixedPoints(int p_opCode, const Geometry* geom0, const Geometry* geom1, const PrecisionModel* p_pm, Noder* p_noder)
     : opCode(p_opCode)
     , pm(p_pm ? p_pm : geom0->getPrecisionModel())
     , geometryFactory(geom0->getFactory())
+    , noder(p_noder)
     , resultDim(OverlayUtil::resultDimension(opCode, geom0->getDimension(), geom1->getDimension()))
 {
     // name the dimensional geometries
@@ -97,9 +100,9 @@ OverlayMixedPoints::OverlayMixedPoints(int p_opCode, const Geometry* geom0, cons
 
 /*public static*/
 std::unique_ptr<Geometry>
-OverlayMixedPoints::overlay(int opCode, const Geometry* geom0, const Geometry* geom1, const PrecisionModel* pm)
+OverlayMixedPoints::overlay(int opCode, const Geometry* geom0, const Geometry* geom1, const PrecisionModel* pm, Noder* p_noder)
 {
-    OverlayMixedPoints overlay(opCode, geom0, geom1, pm);
+    OverlayMixedPoints overlay(opCode, geom0, geom1, pm, p_noder);
     return overlay.getResult();
 }
 
@@ -137,8 +140,11 @@ std::unique_ptr<PointOnGeometryLocator>
 OverlayMixedPoints::createLocator(const Geometry* p_geomNonPoint)
 {
     if (geomNonPointDim == 2) {
-        std::unique_ptr<PointOnGeometryLocator> ipial(new IndexedPointInAreaLocator(*p_geomNonPoint));
-        return ipial;
+        if (p_geomNonPoint->hasCurvedComponents()) {
+            return std::make_unique<SimplePointInAreaLocator>(*p_geomNonPoint);
+        } else {
+            return std::make_unique<IndexedPointInAreaLocator>(*p_geomNonPoint);
+        }
     }
     else {
         std::unique_ptr<PointOnGeometryLocator> ipoll(new IndexedPointOnLineLocator(*p_geomNonPoint));
@@ -159,7 +165,7 @@ OverlayMixedPoints::prepareNonPoint(const Geometry* geomInput)
         return geomInput->clone();
     }
     // Node and round the non-point geometry for output
-    return OverlayNG::geomunion(geomInput, pm);
+    return OverlayNG::geomunion(geomInput, pm, noder);
 }
 
 /*private*/
@@ -175,11 +181,11 @@ std::unique_ptr<Geometry>
 OverlayMixedPoints::computeUnion(const CoordinateSequence* coords)
 {
     std::vector<std::unique_ptr<Point>> resultPointList = findPoints(false, coords);
-    std::vector<std::unique_ptr<LineString>> resultLineList;
+    std::vector<std::unique_ptr<Curve>> resultLineList;
     if (geomNonPointDim == 1) {
         resultLineList = extractLines(geomNonPoint.get());
     }
-    std::vector<std::unique_ptr<Polygon>> resultPolyList;
+    std::vector<std::unique_ptr<Surface>> resultPolyList;
     if (geomNonPointDim == 2) {
         resultPolyList = extractPolygons(geomNonPoint.get());
     }
@@ -274,7 +280,7 @@ OverlayMixedPoints::hasLocation(bool isCovered, const CoordinateXY& coord) const
 
 /*private*/
 std::unique_ptr<CoordinateSequence>
-OverlayMixedPoints::extractCoordinates(const Geometry* points, const PrecisionModel* p_pm) const
+OverlayMixedPoints::extractCoordinates(const Geometry* points, const PrecisionModel* p_pm)
 {
     auto coords = detail::make_unique<CoordinateSequence>(0u, points->hasZ(), points->hasM());
     coords->reserve(points->getNumPoints());
@@ -285,12 +291,12 @@ OverlayMixedPoints::extractCoordinates(const Geometry* points, const PrecisionMo
 }
 
 /*private*/
-std::vector<std::unique_ptr<Polygon>>
-OverlayMixedPoints::extractPolygons(const Geometry* geom) const
+std::vector<std::unique_ptr<Surface>>
+OverlayMixedPoints::extractPolygons(const Geometry* geom)
 {
-    std::vector<std::unique_ptr<Polygon>> list;
+    std::vector<std::unique_ptr<Surface>> list;
     for (std::size_t i = 0; i < geom->getNumGeometries(); i++) {
-        const Polygon* poly = static_cast<const Polygon*>(geom->getGeometryN(i));
+        const Surface* poly = static_cast<const Surface*>(geom->getGeometryN(i));
         if(!poly->isEmpty()) {
             list.emplace_back(poly->clone());
         }
@@ -299,12 +305,12 @@ OverlayMixedPoints::extractPolygons(const Geometry* geom) const
 }
 
 /*private*/
-std::vector<std::unique_ptr<LineString>>
-OverlayMixedPoints::extractLines(const Geometry* geom) const
+std::vector<std::unique_ptr<Curve>>
+OverlayMixedPoints::extractLines(const Geometry* geom)
 {
-    std::vector<std::unique_ptr<LineString>> list;
+    std::vector<std::unique_ptr<Curve>> list;
     for (std::size_t i = 0; i < geom->getNumGeometries(); i++) {
-        const LineString* line = static_cast<const LineString*>(geom->getGeometryN(i));
+        const Curve* line = static_cast<const Curve*>(geom->getGeometryN(i));
         if (! line->isEmpty()) {
             list.emplace_back(line->clone());
         }
diff --git a/src/operation/overlayng/OverlayNG.cpp b/src/operation/overlayng/OverlayNG.cpp
index 43f952f15..70acfbe59 100644
--- a/src/operation/overlayng/OverlayNG.cpp
+++ b/src/operation/overlayng/OverlayNG.cpp
@@ -175,7 +175,7 @@ OverlayNG::getResult()
     }
     else if (! inputGeom.isSingle() &&  inputGeom.hasPoints()) {
         // handle Point-nonPoint inputs
-        result = OverlayMixedPoints::overlay(opCode, ig0, ig1, pm);
+        result = OverlayMixedPoints::overlay(opCode, ig0, ig1, pm, noder);
     }
     else {
         // handle case where both inputs are formed of edges (Lines and Polygons)
@@ -309,10 +309,10 @@ OverlayNG::extractResult(int p_opCode, OverlayGraph* graph)
     //--- Build polygons
     std::vector<OverlayEdge*> resultAreaEdges = graph->getResultAreaEdges();
     PolygonBuilder polyBuilder(resultAreaEdges, geomFact);
-    std::vector<std::unique_ptr<Polygon>> resultPolyList = polyBuilder.getPolygons();
+    std::vector<std::unique_ptr<Surface>> resultPolyList = polyBuilder.getPolygons();
     bool hasResultAreaComponents = (!resultPolyList.empty());
 
-    std::vector<std::unique_ptr<LineString>> resultLineList;
+    std::vector<std::unique_ptr<Curve>> resultLineList;
     std::vector<std::unique_ptr<Point>> resultPointList;
 
     GEOS_CHECK_FOR_INTERRUPTS();
diff --git a/src/operation/overlayng/OverlayUtil.cpp b/src/operation/overlayng/OverlayUtil.cpp
index aa7138a45..313837a34 100644
--- a/src/operation/overlayng/OverlayUtil.cpp
+++ b/src/operation/overlayng/OverlayUtil.cpp
@@ -16,6 +16,7 @@
 
 #include <geos/operation/overlayng/InputGeometry.h>
 #include <geos/operation/overlayng/OverlayGraph.h>
+#include <geos/geom/CircularString.h>
 #include <geos/geom/Coordinate.h>
 #include <geos/geom/Envelope.h>
 #include <geos/geom/GeometryFactory.h>
@@ -279,8 +280,8 @@ OverlayUtil::isResultAreaConsistent(
 /*public static*/
 std::unique_ptr<Geometry>
 OverlayUtil::createResultGeometry(
-    std::vector<std::unique_ptr<Polygon>>& resultPolyList,
-    std::vector<std::unique_ptr<LineString>>& resultLineList,
+    std::vector<std::unique_ptr<Surface>>& resultPolyList,
+    std::vector<std::unique_ptr<Curve>>& resultLineList,
     std::vector<std::unique_ptr<Point>>& resultPointList,
     const GeometryFactory* geometryFactory)
 {
@@ -305,16 +306,22 @@ OverlayUtil::createResultGeometry(
 std::unique_ptr<Geometry>
 OverlayUtil::toLines(OverlayGraph* graph, bool isOutputEdges, const GeometryFactory* geomFact)
 {
-    std::vector<std::unique_ptr<LineString>> lines;
+    std::vector<std::unique_ptr<Geometry>> lines;
     std::vector<OverlayEdge*>& edges = graph->getEdges();
     for (OverlayEdge* edge : edges) {
       bool includeEdge = isOutputEdges || edge->isInResultArea();
       if (! includeEdge) continue;
 
       const auto& pts = edge->getCoordinatesOriented();
-      std::unique_ptr<LineString> line = geomFact->createLineString(pts);
+
+      std::unique_ptr<Geometry> edgeGeom;
+      if (edge->isCurved()) {
+        edgeGeom = geomFact->createCircularString(pts);
+      } else {
+        edgeGeom = geomFact->createLineString(pts);
+      }
       // line->setUserData(labelForResult(edge));
-      lines.push_back(std::move(line));
+      lines.push_back(std::move(edgeGeom));
     }
     return geomFact->buildGeometry(std::move(lines));
 }
diff --git a/src/operation/overlayng/PolygonBuilder.cpp b/src/operation/overlayng/PolygonBuilder.cpp
index 8cc88d306..d134832a4 100644
--- a/src/operation/overlayng/PolygonBuilder.cpp
+++ b/src/operation/overlayng/PolygonBuilder.cpp
@@ -20,7 +20,7 @@
 #include <geos/util/TopologyException.h>
 
 
-using geos::geom::Polygon;
+using geos::geom::Surface;
 
 namespace geos {      // geos
 namespace operation { // geos.operation
@@ -28,7 +28,7 @@ namespace overlayng { // geos.operation.overlayng
 
 
 /*public*/
-std::vector<std::unique_ptr<Polygon>>
+std::vector<std::unique_ptr<Surface>>
 PolygonBuilder::getPolygons() const
 {
     return computePolygons(shellList);
@@ -42,14 +42,14 @@ PolygonBuilder::getShellRings() const
 }
 
 /*private*/
-std::vector<std::unique_ptr<Polygon>>
+std::vector<std::unique_ptr<Surface>>
 PolygonBuilder::computePolygons(const std::vector<OverlayEdgeRing*>& shells) const
 {
-    std::vector<std::unique_ptr<Polygon>> resultPolyList;
+    std::vector<std::unique_ptr<Surface>> resultPolyList;
     resultPolyList.reserve(shells.size());
     // add Polygons for all shells
     for (OverlayEdgeRing* er : shells) {
-        std::unique_ptr<Polygon> poly = er->toPolygon(geometryFactory);
+        std::unique_ptr<Surface> poly = er->toSurface(geometryFactory);
         resultPolyList.push_back(std::move(poly));
     }
     return resultPolyList;
diff --git a/tests/unit/operation/overlayng/OverlayNGTest.cpp b/tests/unit/operation/overlayng/OverlayNGTest.cpp
index ce7323121..92f1d32a1 100644
--- a/tests/unit/operation/overlayng/OverlayNGTest.cpp
+++ b/tests/unit/operation/overlayng/OverlayNGTest.cpp
@@ -6,12 +6,16 @@
 
 // geos
 #include <geos/operation/overlayng/OverlayNG.h>
+#include <geos/noding/SimpleNoder.h>
+#include <geos/algorithm/CircularArcIntersector.h>
+#include <geos/noding/ArcIntersectionAdder.h>
 
 // std
 #include <memory>
 
 using namespace geos::geom;
 using namespace geos::operation::overlayng;
+using namespace geos::noding;
 using geos::io::WKTReader;
 using geos::io::WKTWriter;
 
@@ -25,6 +29,13 @@ struct test_overlayng_data {
 
     WKTReader r;
     WKTWriter w;
+    double tol{0.0};
+
+    void
+    setEqualityTolerance(double d)
+    {
+        tol = d;
+    }
 
     void
     testOverlay(const std::string& a, const std::string& b, const std::string& expected, int opCode, double scaleFactor)
@@ -38,10 +49,25 @@ struct test_overlayng_data {
         std::unique_ptr<Geometry> geom_a = r.read(a);
         std::unique_ptr<Geometry> geom_b = r.read(b);
         std::unique_ptr<Geometry> geom_expected = r.read(expected);
-        std::unique_ptr<Geometry> geom_result = OverlayNG::overlay(geom_a.get(), geom_b.get(), opCode, pm.get());
-        // std::string wkt_result = w.write(geom_result.get());
-        // std::cout << std::endl << wkt_result << std::endl;
-        ensure_equals_geometry(geom_expected.get(), geom_result.get());
+
+
+        std::unique_ptr<Geometry> geom_result;
+        if (geom_a->hasCurvedComponents() || geom_b->hasCurvedComponents()) {
+            SimpleNoder noder;
+            geos::algorithm::CircularArcIntersector cai;
+            ArcIntersectionAdder aia(cai);
+
+            noder.setArcIntersector(aia);
+            OverlayNG ong(geom_a.get(), geom_b.get(), pm.get(), opCode);
+            ong.setNoder(&noder);
+
+            geom_result = ong.getResult();
+        } else {
+            geom_result = OverlayNG::overlay(geom_a.get(), geom_b.get(), opCode, pm.get());
+        }
+        //std::string wkt_result = w.write(geom_result.get());
+        //std::cout << std::endl << wkt_result << std::endl;
+        ensure_equals_geometry_xyzm(geom_result.get(), geom_expected.get(), tol);
     }
 
     void
@@ -59,7 +85,7 @@ struct test_overlayng_data {
         std::unique_ptr<Geometry> geom_result = OverlayNG::overlay(geom_a.get(), geom_b.get(), opCode, pm.get());
         // std::string wkt_result = w.write(geom_result.get());
         // std::cout << std::endl << wkt_result << std::endl;
-        ensure_equals_exact_geometry(geom_expected.get(), geom_result.get(), 0);
+        ensure_equals_exact_geometry(geom_expected.get(), geom_result.get(), tol);
     }
 
     void
@@ -582,4 +608,197 @@ void object::test<45> ()
     testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
 }
 
+template<>
+template<>
+void object::test<46> ()
+{
+    set_test_name("CurvePolygon/CurvePolygon intersection -> CurvePolygon");
+
+    std::string a = "CURVEPOLYGON (COMPOUNDCURVE((10 0, 0 0, 0 10, 10 10), CIRCULARSTRING (10 10, 15 5, 10 0)))";
+    std::string b = "CURVEPOLYGON (COMPOUNDCURVE((10 10, 20 10, 20 0, 10 0), CIRCULARSTRING (10 0, 5 5, 10 10)))";
+    std::string exp = "CURVEPOLYGON (CIRCULARSTRING (10 10, 15 5, 10 0, 5 5, 10 10))";
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<47>()
+{
+    set_test_name("CurvePolygon/CurvePolygon symdifference -> MultiSurface");
+
+    std::string a = "CURVEPOLYGON (COMPOUNDCURVE((10 0, 0 0, 0 10, 10 10), CIRCULARSTRING (10 10, 15 5, 10 0)))";
+    std::string b = "CURVEPOLYGON (COMPOUNDCURVE((10 10, 20 10, 20 0, 10 0), CIRCULARSTRING (10 0, 5 5, 10 10)))";
+    std::string exp = "MULTISURFACE (CURVEPOLYGON (COMPOUNDCURVE ((10 0, 0 0, 0 10, 10 10), CIRCULARSTRING (10 10, 5 5, 10 0))), CURVEPOLYGON (COMPOUNDCURVE (CIRCULARSTRING (10 0, 15 5, 10 10), (10 10, 20 10, 20 0, 10 0))))";
+    testOverlay(a, b, exp, OverlayNG::SYMDIFFERENCE, 0);
+}
+
+template<>
+template<>
+void object::test<48>()
+{
+    set_test_name("Polygon/CircularString intersection -> CircularString");
+
+    std::string a = "POLYGON ((10 0, 10 10, 0 10, 0 0, 10 0))";
+    std::string b = "CIRCULARSTRING (5 0, 10 5, 15 0)";
+    std::string exp = "CIRCULARSTRING (5 0, 6.464466094067262 3.5355339059327378, 10 5)";
+
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<49>()
+{
+    set_test_name("CircularString / CircularString intersection -> MultiPoint");
+
+    std::string a = "CIRCULARSTRING (-5 0, 0 5, 5 0)";
+    std::string b = "CIRCULARSTRING (-5 5, 0 0, 5 5)";
+    std::string exp = "MULTIPOINT ((4.330127018922194 2.5), (-4.330127018922194 2.5))";
+
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<50>()
+{
+    set_test_name("CircularString / CircularString intersection -> MultiCurve");
+    std::string a = "CIRCULARSTRING (-5 0, 0 5, 5 0)";
+    std::string b = "CIRCULARSTRING (4 3, 0 -5, -4 3)";
+    std::string exp = "MULTICURVE (CIRCULARSTRING (-5 0, -4.743416490252569 1.58113883008419, -4 3), CIRCULARSTRING (4 3, 4.743416490252569 1.5811388300841898, 5 0))";
+
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<51>()
+{
+    set_test_name("CircularString / CircularString difference -> CircularString");
+    std::string a = "CIRCULARSTRING (-5 0, 0 5, 5 0)";
+    std::string b = "CIRCULARSTRING (4 3, 0 -5, -4 3)";
+    std::string exp = "CIRCULARSTRING (-4 3, 0 5, 4 3)";
+
+    setEqualityTolerance(1e-15);
+    testOverlay(a, b, exp, OverlayNG::DIFFERENCE, 0);
+}
+
+template<>
+template<>
+void object::test<52>()
+{
+    set_test_name("CircularString / CircularString symdifference -> MultiCurve");
+    std::string a = "CIRCULARSTRING (-5 0, 0 5, 5 0)";
+    std::string b = "CIRCULARSTRING (4 3, 0 -5, -4 3)";
+    std::string exp = "MULTICURVE (CIRCULARSTRING (-4 3, 0 5, 4 3), CIRCULARSTRING (5 0, 0 -5, -5 0))";
+
+    setEqualityTolerance(1e-15);
+    testOverlay(a, b, exp, OverlayNG::SYMDIFFERENCE, 0);
+}
+
+template<>
+template<>
+void object::test<53>()
+{
+    set_test_name("CompoundCurves / LineString -> MultiPoint");
+
+    std::string a = "COMPOUNDCURVE ((-5 0, -1 0), CIRCULARSTRING (-1 0, 0 1, 1 0))";
+    std::string b = "LINESTRING (-3 -1, -4 1, 1 0)";
+    std::string exp = "MULTIPOINT ((-0.923076923076923 0.3846153846153846), (1 0), (-3.5 0))";
+
+    setEqualityTolerance(1e-15);
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<54>()
+{
+    set_test_name("CircularString / CircularString -> Point (tangent)");
+
+    std::string a = "CIRCULARSTRING (5 3, 5 0, 0 -5, -5 0, 4 3)";
+    std::string b = "CIRCULARSTRING (-5 10, 0 15, 5 10, 4 7, -5 10)";
+    std::string exp = "POINT (0 5)";
+
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<55>()
+{
+    set_test_name("Polygon / CurvePolygon -> CurvePolygon");
+
+    std::string a = "POLYGON ((0 0, 10 0, 10 10, 0 10, 0 0))";
+    std::string b = "CURVEPOLYGON (CIRCULARSTRING (4 5, 5 6, 6 5, 5 4, 4 5))";
+    std::string exp = "CURVEPOLYGON ((0 0, 10 0, 10 10, 0 10, 0 0), CIRCULARSTRING (4 5, 5 6, 6 5, 5 4, 4 5))";
+
+    testOverlay(a, b, exp, OverlayNG::DIFFERENCE, 0);
+}
+
+template<>
+template<>
+void object::test<56>()
+{
+    set_test_name("CircularString / Point -> Point");
+
+    std::string a = "CIRCULARSTRING (-5 0, 0 5, 5 0)";
+    std::string b = "POINT (4 3)";
+    std::string exp = b;
+
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<57>()
+{
+    set_test_name("CompoundCurve / MultiPoint -> MultiPoint");
+
+    std::string a = "COMPOUNDCURVE ((-10 5, -5 0), CIRCULARSTRING (-5 0, 0 5, 5 0))";
+    std::string b = "MULTIPOINT (4 3, -7 2, 0 0)";
+    std::string exp = "MULTIPOINT (4 3, -7 2)";
+
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<58>()
+{
+    set_test_name("CurvePolygon / MultiPoint -> MultiPoint");
+
+    std::string a = "CURVEPOLYGON (COMPOUNDCURVE( CIRCULARSTRING(-5 0, 0 5, 5 0), (5 0, -5 0)))";
+    std::string b = "MULTIPOINT (0 0, 4 3, 2 2, 4 4)";
+    std::string exp = "MULTIPOINT (0 0, 4 3, 2 2)";
+    
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<59>()
+{
+    set_test_name("MultiSurface / MultiPoint -> MultiPoint");
+
+    std::string a = "MULTISURFACE(CURVEPOLYGON (COMPOUNDCURVE( CIRCULARSTRING(-5 0, 0 5, 5 0), (5 0, -5 0))), ((4 4, 5 4, 5 5, 4 4)))";
+    std::string b = "MULTIPOINT (0 0, 4 3, 2 2, 4.5 4.1)";
+    std::string exp = b;
+
+    testOverlay(a, b, exp, OverlayNG::INTERSECTION, 0);
+}
+
+template<>
+template<>
+void object::test<60>()
+{
+    set_test_name("MultiSurface / MultiPoint -> MultiSurface");
+
+    std::string a = "MULTISURFACE(CURVEPOLYGON (COMPOUNDCURVE( CIRCULARSTRING(-5 0, 0 5, 5 0), (5 0, -5 0))), ((4 4, 5 4, 5 5, 4 4)))";
+    std::string b = "MULTIPOINT (0 0, 4 3, 2 2, 4.5 4.1)";
+    std::string exp = a;
+
+    testOverlay(a, b, exp, OverlayNG::UNION, 0);
+}
+
 } // namespace tut

commit fa14b9a717e2231679859d20adae502ebff07492
Author: Daniel Baston <dbaston at gmail.com>
Date:   Thu Mar 19 13:04:00 2026 -0400

    EdgeNodingBuilder: Accept CircularString input

diff --git a/include/geos/operation/overlayng/Edge.h b/include/geos/operation/overlayng/Edge.h
index 2af2a0c67..7ec26eb16 100644
--- a/include/geos/operation/overlayng/Edge.h
+++ b/include/geos/operation/overlayng/Edge.h
@@ -64,6 +64,7 @@ private:
     int bDepthDelta = 0;
     bool bIsHole = false;
     std::shared_ptr<const geom::CoordinateSequence> pts;
+    bool ptsCurved;
 
     // Methods
 
@@ -183,6 +184,7 @@ private:
 
 public:
 
+#if 0
     Edge()
         : aDim(OverlayLabel::DIM_UNKNOWN)
         , aDepthDelta(0)
@@ -192,15 +194,20 @@ public:
         , bIsHole(false)
         , pts(nullptr)
         {};
+#endif
+
+    Edge(const std::shared_ptr<const geom::CoordinateSequence>& p_pts, const EdgeSourceInfo* info, bool isCurved);
 
     friend std::ostream& operator<<(std::ostream& os, const Edge& e);
 
     static bool isCollapsed(const geom::CoordinateSequence* pts);
 
-    Edge(const std::shared_ptr<const geom::CoordinateSequence>& p_pts, const EdgeSourceInfo* info);
+    bool isCurved() const {
+        return ptsCurved;
+    }
 
     // return a clone of the underlying points
-    std::unique_ptr<geom::CoordinateSequence> getCoordinates()
+    std::unique_ptr<geom::CoordinateSequence> getCoordinates() const
     {
         return pts->clone();
     };
diff --git a/include/geos/operation/overlayng/EdgeNodingBuilder.h b/include/geos/operation/overlayng/EdgeNodingBuilder.h
index 0927241ba..d981a51d5 100644
--- a/include/geos/operation/overlayng/EdgeNodingBuilder.h
+++ b/include/geos/operation/overlayng/EdgeNodingBuilder.h
@@ -20,12 +20,14 @@
 
 #include <geos/algorithm/LineIntersector.h>
 #include <geos/geom/CoordinateSequence.h>
+#include <geos/geom/CircularArc.h>
 #include <geos/geom/Envelope.h>
 #include <geos/geom/Geometry.h>
 #include <geos/geom/GeometryCollection.h>
 #include <geos/geom/LinearRing.h>
 #include <geos/geom/LineString.h>
 #include <geos/geom/Polygon.h>
+#include <geos/geom/SimpleCurve.h>
 #include <geos/noding/IntersectionAdder.h>
 #include <geos/noding/Noder.h>
 #include <geos/noding/SegmentString.h>
@@ -65,11 +67,16 @@ class GEOS_DLL EdgeNodingBuilder {
     using PrecisionModel = geos::geom::PrecisionModel;
     using Envelope = geos::geom::Envelope;
     using GeometryCollection = geos::geom::GeometryCollection;
+    using Surface = geos::geom::Surface;
     using Polygon = geos::geom::Polygon;
     using CoordinateSequence = geos::geom::CoordinateSequence;
+    using CompoundCurve = geos::geom::CompoundCurve;
+    using CircularString = geos::geom::CircularString;
     using LinearRing = geos::geom::LinearRing;
     using LineString = geos::geom::LineString;
     using Geometry = geos::geom::Geometry;
+    using SimpleCurve = geos::geom::SimpleCurve;
+    using Curve = geos::geom::Curve;
 
 private:
 
@@ -79,7 +86,7 @@ private:
 
     // Members
     const PrecisionModel* pm;
-    std::unique_ptr<std::vector<noding::SegmentString*>> inputEdges;
+    std::vector<noding::PathString*> inputEdges;
     noding::Noder* customNoder;
     std::array<bool, 2> hasEdges;
     const Envelope* clipEnv;
@@ -112,11 +119,17 @@ private:
 
     void addCollection(const GeometryCollection* gc, uint8_t geomIndex);
     void addGeometryCollection(const GeometryCollection* gc, uint8_t geomIndex, int expectedDim);
-    void addPolygon(const Polygon* poly, uint8_t geomIndex);
-    void addPolygonRing(const LinearRing* ring, bool isHole, uint8_t geomIndex);
-    void addLine(const LineString* line, uint8_t geomIndex);
-    void addLine(std::unique_ptr<CoordinateSequence>& pts, uint8_t geomIndex);
-    void addEdge(std::unique_ptr<CoordinateSequence>& cas, const EdgeSourceInfo* info);
+    void addPolygon(const Surface* poly, uint8_t geomIndex);
+    void addPolygonRing(const Curve* ring, bool isHole, uint8_t geomIndex);
+    void addSimpleCurve(const SimpleCurve* line, uint8_t geomIndex);
+    void addCompoundCurve(const CompoundCurve* line, uint8_t geomIndex);
+
+    void addCurve(const std::shared_ptr<const CoordinateSequence>& pts, const std::vector<geom::CircularArc>& arcs, uint8_t geomIndex);
+    void addLine(const std::shared_ptr<const CoordinateSequence>& pts, uint8_t geomIndex);
+
+    void addEdge(const std::shared_ptr<const CoordinateSequence>& cas, const EdgeSourceInfo* info);
+    void addCurvedEdge(const std::shared_ptr<const CoordinateSequence>& cas, const std::vector<geom::CircularArc>& arcs, const EdgeSourceInfo* info);
+
 
     // Create a EdgeSourceInfo* owned by EdgeNodingBuilder
     const EdgeSourceInfo* createEdgeSourceInfo(uint8_t index, int depthDelta, bool isHole);
@@ -156,7 +169,7 @@ private:
     * @param ring the line to clip
     * @return the points in the clipped line
     */
-    std::unique_ptr<CoordinateSequence> clip(const LinearRing* line);
+    std::shared_ptr<const CoordinateSequence> clip(const LineString* ring) const;
 
     /**
     * Removes any repeated points from a linear component.
@@ -165,9 +178,9 @@ private:
     * @param line the line to process
     * @return the points of the line with repeated points removed
     */
-    static std::unique_ptr<CoordinateSequence> removeRepeatedPoints(const LineString* line);
+    static std::shared_ptr<const CoordinateSequence> removeRepeatedPoints(const LineString* line);
 
-    static int computeDepthDelta(const LinearRing* ring, bool isHole);
+    static int computeDepthDelta(const CoordinateSequence* ringCoords, bool isHole);
 
     void add(const Geometry* g, uint8_t geomIndex);
 
@@ -177,8 +190,8 @@ private:
     * which is used to provide source topology info to the constructed Edges
     * (and is then discarded).
     */
-    std::vector<Edge*> node(const std::vector<noding::SegmentString*>& segStrings);
-    std::vector<Edge*> createEdges(std::vector<std::unique_ptr<noding::SegmentString>> &segStrings);
+    std::vector<Edge*> node(const std::vector<noding::PathString*>& segStrings);
+    std::vector<Edge*> createEdges(std::vector<std::unique_ptr<noding::PathString>> &segStrings);
 
 
 public:
@@ -190,7 +203,6 @@ public:
     */
     EdgeNodingBuilder(const PrecisionModel* p_pm, noding::Noder* p_customNoder)
         : pm(p_pm)
-        , inputEdges(new std::vector<noding::SegmentString*>)
         , customNoder(p_customNoder)
         , hasEdges{{false,false}}
         , clipEnv(nullptr)
diff --git a/src/operation/overlayng/Edge.cpp b/src/operation/overlayng/Edge.cpp
index 7f231d722..2c4e8634a 100644
--- a/src/operation/overlayng/Edge.cpp
+++ b/src/operation/overlayng/Edge.cpp
@@ -27,7 +27,7 @@ using namespace geos::geom;
 using geos::util::GEOSException;
 
 /*public*/
-Edge::Edge(const std::shared_ptr<const CoordinateSequence>& p_pts, const EdgeSourceInfo* info)
+Edge::Edge(const std::shared_ptr<const CoordinateSequence>& p_pts, const EdgeSourceInfo* info, bool p_isCurved)
     : aDim(OverlayLabel::DIM_UNKNOWN)
     , aDepthDelta(0)
     , aIsHole(false)
@@ -35,6 +35,7 @@ Edge::Edge(const std::shared_ptr<const CoordinateSequence>& p_pts, const EdgeSou
     , bDepthDelta(0)
     , bIsHole(false)
     , pts(p_pts)
+    , ptsCurved(p_isCurved)
 {
     copyInfo(info);
 }
diff --git a/src/operation/overlayng/EdgeNodingBuilder.cpp b/src/operation/overlayng/EdgeNodingBuilder.cpp
index b063770f1..13c123315 100644
--- a/src/operation/overlayng/EdgeNodingBuilder.cpp
+++ b/src/operation/overlayng/EdgeNodingBuilder.cpp
@@ -16,10 +16,13 @@
  *
  **********************************************************************/
 
+#include <geos/algorithm/Orientation.h>
+#include <geos/geom/CompoundCurve.h>
+#include <geos/geom/CircularString.h>
 #include <geos/noding/ValidatingNoder.h>
 #include <geos/noding/NodedSegmentString.h>
 #include <geos/noding/MCIndexNoder.h>
-#include <geos/algorithm/Orientation.h>
+#include <geos/noding/NodableArcString.h>
 #include <geos/noding/snapround/SnapRoundingNoder.h>
 #include <geos/operation/overlayng/EdgeNodingBuilder.h>
 #include <geos/operation/overlayng/EdgeMerger.h>
@@ -36,15 +39,17 @@ using namespace geos::geom;
 using geos::operation::valid::RepeatedPointRemover;
 using geos::noding::snapround::SnapRoundingNoder;
 using geos::noding::Noder;
+using geos::noding::NodableArcString;
 using geos::noding::MCIndexNoder;
 using geos::noding::ValidatingNoder;
 using geos::noding::SegmentString;
 using geos::noding::NodedSegmentString;
+using geos::noding::PathString;
 
 
 EdgeNodingBuilder::~EdgeNodingBuilder()
 {
-    for (SegmentString* ss: *inputEdges) {
+    for (auto* ss: inputEdges) {
         delete ss;
     }
 }
@@ -108,7 +113,7 @@ EdgeNodingBuilder::build(const Geometry* geom0, const Geometry* geom1)
 
     add(geom0, 0);
     add(geom1, 1);
-    std::vector<Edge*> nodedEdges = node(*inputEdges);
+    std::vector<Edge*> nodedEdges = node(inputEdges);
 
     /**
      * Merge the noded edges to eliminate duplicates.
@@ -119,14 +124,14 @@ EdgeNodingBuilder::build(const Geometry* geom0, const Geometry* geom1)
 
 /*private*/
 std::vector<Edge*>
-EdgeNodingBuilder::node(const std::vector<SegmentString*>& segStrings)
+EdgeNodingBuilder::node(const std::vector<PathString*>& segStrings)
 {
     std::vector<Edge*> nodedEdges;
 
     Noder* noder = getNoder();
-    noder->computeNodes(segStrings);
+    noder->computePathNodes(segStrings);
 
-    auto nodedSS = noder->getNodedSubstrings();
+    auto nodedSS = noder->getNodedPaths();
 
     nodedEdges = createEdges(nodedSS);
 
@@ -135,13 +140,15 @@ EdgeNodingBuilder::node(const std::vector<SegmentString*>& segStrings)
 
 /*private*/
 std::vector<Edge*>
-EdgeNodingBuilder::createEdges(std::vector<std::unique_ptr<SegmentString>>& segStrings)
+EdgeNodingBuilder::createEdges(std::vector<std::unique_ptr<PathString>>& segStrings)
 {
     std::vector<Edge*> createdEdges;
 
     for (auto& ss : segStrings) {
         const auto& pts = ss->getCoordinates();
 
+        const bool isCurved = dynamic_cast<const noding::ArcString*>(ss.get());
+
         // don't create edges from collapsed lines
         if (Edge::isCollapsed(pts.get())) continue;
 
@@ -150,7 +157,7 @@ EdgeNodingBuilder::createEdges(std::vector<std::unique_ptr<SegmentString>>& segS
         // Record that a non-collapsed edge exists for the parent geometry
         hasEdges[info->getIndex()] = true;
         // Allocate the new Edge locally in a std::deque
-        edgeQue.emplace_back(ss->getCoordinates(), info);
+        edgeQue.emplace_back(ss->getCoordinates(), info, isCurved);
         Edge* newEdge = &(edgeQue.back());
         createdEdges.push_back(newEdge);
     }
@@ -179,12 +186,18 @@ EdgeNodingBuilder::add(const Geometry* g, uint8_t geomIndex)
     switch (g->getGeometryTypeId())
     {
         case GEOS_POLYGON:
-            return addPolygon(static_cast<const Polygon*>(g), geomIndex);
+        case GEOS_CURVEPOLYGON:
+            return addPolygon(static_cast<const Surface*>(g), geomIndex);
         case GEOS_LINESTRING:
         case GEOS_LINEARRING:
-            return addLine(static_cast<const LineString*>(g), geomIndex);
+        case GEOS_CIRCULARSTRING:
+            return addSimpleCurve(static_cast<const SimpleCurve*>(g), geomIndex);
+        case GEOS_COMPOUNDCURVE:
+            return addCompoundCurve(static_cast<const CompoundCurve*>(g), geomIndex);
         case GEOS_MULTILINESTRING:
         case GEOS_MULTIPOLYGON:
+        case GEOS_MULTICURVE:
+        case GEOS_MULTISURFACE:
             return addCollection(static_cast<const GeometryCollection*>(g), geomIndex);
         case GEOS_GEOMETRYCOLLECTION:
             return addGeometryCollection(static_cast<const GeometryCollection*>(g), geomIndex, g->getDimension());
@@ -192,6 +205,7 @@ EdgeNodingBuilder::add(const Geometry* g, uint8_t geomIndex)
         case GEOS_MULTIPOINT:
             return; // do nothing
         default:
+            throw util::IllegalArgumentException("Unexpected geometry type: " + g->getGeometryType());
             return; // do nothing
     }
 }
@@ -221,13 +235,13 @@ EdgeNodingBuilder::addGeometryCollection(const GeometryCollection* gc, uint8_t g
 
 /*private*/
 void
-EdgeNodingBuilder::addPolygon(const Polygon* poly, uint8_t geomIndex)
+EdgeNodingBuilder::addPolygon(const Surface* poly, uint8_t geomIndex)
 {
-    const LinearRing* shell = poly->getExteriorRing();
+    const Curve* shell = poly->getExteriorRing();
     addPolygonRing(shell, false, geomIndex);
 
     for (std::size_t i = 0; i < poly->getNumInteriorRing(); i++) {
-        const LinearRing* hole = poly->getInteriorRingN(i);
+        const Curve* hole = poly->getInteriorRingN(i);
 
         // Holes are topologically labelled opposite to the shell, since
         // the interior of the polygon lies on their opposite side
@@ -238,25 +252,60 @@ EdgeNodingBuilder::addPolygon(const Polygon* poly, uint8_t geomIndex)
 
 /*private*/
 void
-EdgeNodingBuilder::addPolygonRing(const LinearRing* ring, bool isHole, uint8_t geomIndex)
-  {
+EdgeNodingBuilder::addPolygonRing(const Curve* ring, bool isHole, uint8_t geomIndex)
+{
     // don't add empty rings
     if (ring->isEmpty()) return;
 
     if (isClippedCompletely(ring->getEnvelopeInternal()))
       return;
 
-    std::unique_ptr<geom::CoordinateSequence> pts = clip(ring);
+    const auto type = ring->getGeometryTypeId();
+
+    if (type == GEOS_COMPOUNDCURVE) {
+        const CompoundCurve* cc = static_cast<const CompoundCurve*>(ring);
+        const auto coords = ring->getCoordinates();
+        const int depthDelta = computeDepthDelta(coords.get(), isHole);
+
+        const EdgeSourceInfo* eso = createEdgeSourceInfo(geomIndex, depthDelta, isHole);
+
+        for (std::size_t i = 0; i < cc->getNumCurves(); i++) {
+            const SimpleCurve* section = cc->getCurveN(i);
+            if (section->getNumPoints() >= 2) {
+                if (section->getGeometryTypeId() == GEOS_CIRCULARSTRING) {
+                    const CircularString* cs = static_cast<const CircularString*>(section);
+                    addCurvedEdge(cs->getSharedCoordinates(), cs->getArcs(), eso);
+                } else {
+                    addEdge(section->getSharedCoordinates(), eso);
+                }
+            }
+        }
 
-    /**
-    * Don't add edges that collapse to a point
-    */
-    if (pts->size() < 2) {
         return;
     }
 
-    int depthDelta = computeDepthDelta(ring, isHole);
-    addEdge(pts, createEdgeSourceInfo(geomIndex, depthDelta, isHole));
+    const SimpleCurve* scRing = static_cast<const SimpleCurve*>(ring);
+    const int depthDelta = computeDepthDelta(scRing->getCoordinatesRO(), isHole);
+    const EdgeSourceInfo* esInfo = createEdgeSourceInfo(geomIndex, depthDelta, isHole);
+
+    if (ring->getGeometryTypeId() == GEOS_LINEARRING || ring->getGeometryTypeId() == GEOS_LINESTRING) {
+        // TODO: Support CircularString in RingClipper
+        std::shared_ptr<const CoordinateSequence> pts = clip(static_cast<const LineString*>(ring));
+
+        /**
+        * Don't add edges that collapse to a point
+        */
+        if (pts->size() < 2) {
+            return;
+        }
+
+        addEdge(pts, esInfo);
+    } else {
+        assert(ring->getGeometryTypeId() == GEOS_CIRCULARSTRING);
+
+        const CircularString* cs = static_cast<const CircularString*>(ring);
+        addCurvedEdge(cs->getSharedCoordinates(), cs->getArcs(), esInfo);
+    }
 }
 
 /*private*/
@@ -281,13 +330,20 @@ EdgeNodingBuilder::createEdgeSourceInfo(uint8_t index, int depthDelta, bool isHo
 
 /*private*/
 void
-EdgeNodingBuilder::addEdge(std::unique_ptr<CoordinateSequence>& cas, const EdgeSourceInfo* info)
+EdgeNodingBuilder::addEdge(const std::shared_ptr<const CoordinateSequence>& cas, const EdgeSourceInfo* info)
 {
     // TODO: manage these internally to EdgeNodingBuilder in a std::deque,
     // since they do not have a life span longer than the EdgeNodingBuilder
     // in OverlayNG::buildGraph()
-    NodedSegmentString* ss = new NodedSegmentString(std::move(cas), inputHasZ, inputHasM, reinterpret_cast<const void*>(info));
-    inputEdges->push_back(ss);
+    NodedSegmentString* ss = new NodedSegmentString(cas, inputHasZ, inputHasM, reinterpret_cast<const void*>(info));
+    inputEdges.push_back(ss);
+}
+
+void
+EdgeNodingBuilder::addCurvedEdge(const std::shared_ptr<const CoordinateSequence>& cas, const std::vector<CircularArc>& arcs, const EdgeSourceInfo* info)
+{
+    NodableArcString* as = new NodableArcString(arcs, cas, inputHasZ, inputHasM, reinterpret_cast<const void*>(info));
+    inputEdges.push_back(as);
 }
 
 /*private*/
@@ -299,8 +355,8 @@ EdgeNodingBuilder::isClippedCompletely(const Envelope* env) const
 }
 
 /* private */
-std::unique_ptr<geom::CoordinateSequence>
-EdgeNodingBuilder::clip(const LinearRing* ring)
+std::shared_ptr<const CoordinateSequence>
+EdgeNodingBuilder::clip(const LineString* ring) const
 {
     const Envelope* env = ring->getEnvelopeInternal();
 
@@ -316,16 +372,20 @@ EdgeNodingBuilder::clip(const LinearRing* ring)
 }
 
 /*private*/
-std::unique_ptr<CoordinateSequence>
+std::shared_ptr<const CoordinateSequence>
 EdgeNodingBuilder::removeRepeatedPoints(const LineString* line)
 {
-    const CoordinateSequence* pts = line->getCoordinatesRO();
-    return RepeatedPointRemover::removeRepeatedPoints(pts);
+    const std::shared_ptr<const CoordinateSequence>& pts = line->getSharedCoordinates();
+    if (pts->hasRepeatedPoints()) {
+        return RepeatedPointRemover::removeRepeatedPoints(pts.get());
+    } else {
+        return pts;
+    }
 }
 
 /*private*/
 int
-EdgeNodingBuilder::computeDepthDelta(const LinearRing* ring, bool isHole)
+EdgeNodingBuilder::computeDepthDelta(const CoordinateSequence* ringCoords, bool isHole)
 {
     /**
      * Compute the orientation of the ring, to
@@ -335,7 +395,8 @@ EdgeNodingBuilder::computeDepthDelta(const LinearRing* ring, bool isHole)
      * It is important to compute orientation on the original ring,
      * since topology collapse can make the orientation computation give the wrong answer.
      */
-    bool isCCW = algorithm::Orientation::isCCW(ring->getCoordinatesRO());
+
+    const bool isCCW = algorithm::Orientation::isCCW(ringCoords);
 
     /**
      * Compute whether ring is in canonical orientation or not.
@@ -360,29 +421,46 @@ EdgeNodingBuilder::computeDepthDelta(const LinearRing* ring, bool isHole)
 
 /*private*/
 void
-EdgeNodingBuilder::addLine(const LineString* line, uint8_t geomIndex)
+EdgeNodingBuilder::addSimpleCurve(const SimpleCurve* curve, uint8_t geomIndex)
 {
     // don't add empty lines
-    if (line->isEmpty()) return;
+    if (curve->isEmpty()) return;
 
-    if (isClippedCompletely(line->getEnvelopeInternal()))
+    if (isClippedCompletely(curve->getEnvelopeInternal()))
         return;
 
+    if (curve->getGeometryTypeId() == GEOS_CIRCULARSTRING) {
+        // TODO: Support CircularString in LineLimiter
+        const CircularString* cs = static_cast<const CircularString*>(curve);
+        addCurve(cs->getSharedCoordinates(), cs->getArcs(), geomIndex);
+        return;
+    }
+
+    const LineString* line = detail::down_cast<const LineString*>(curve);
+
     if (isToBeLimited(line)) {
         std::vector<std::unique_ptr<CoordinateSequence>>& sections = limit(line);
         for (auto& pts : sections) {
-            addLine(pts, geomIndex);
+            addLine(std::move(pts), geomIndex);
         }
     }
     else {
-        std::unique_ptr<CoordinateSequence> ptsNoRepeat = removeRepeatedPoints(line);
+        const auto ptsNoRepeat = removeRepeatedPoints(line);
         addLine(ptsNoRepeat, geomIndex);
     }
 }
 
+void
+EdgeNodingBuilder::addCompoundCurve(const CompoundCurve* curve, uint8_t geomIndex)
+{
+    for (std::size_t i = 0; i < curve->getNumCurves(); i++) {
+        addSimpleCurve(curve->getCurveN(i), geomIndex);
+    }
+}
+
 /*private*/
 void
-EdgeNodingBuilder::addLine(std::unique_ptr<CoordinateSequence>& pts, uint8_t geomIndex)
+EdgeNodingBuilder::addLine(const std::shared_ptr<const CoordinateSequence>& pts, uint8_t geomIndex)
 {
     /**
      * Don't add edges that collapse to a point
@@ -394,6 +472,20 @@ EdgeNodingBuilder::addLine(std::unique_ptr<CoordinateSequence>& pts, uint8_t geo
     addEdge(pts, createEdgeSourceInfo(geomIndex));
 }
 
+/*private*/
+void
+EdgeNodingBuilder::addCurve(const std::shared_ptr<const CoordinateSequence>& pts, const std::vector<CircularArc>& arcs, uint8_t geomIndex)
+{
+    /**
+     * Don't add edges that collapse to a point
+     */
+    if (pts->size() < 2) {
+        return;
+    }
+
+    addCurvedEdge(pts, arcs, createEdgeSourceInfo(geomIndex));
+}
+
 /*private*/
 bool
 EdgeNodingBuilder::isToBeLimited(const LineString* line) const
diff --git a/tests/unit/operation/overlayng/EdgeNodingBuilderTest.cpp b/tests/unit/operation/overlayng/EdgeNodingBuilderTest.cpp
new file mode 100644
index 000000000..017dffc9a
--- /dev/null
+++ b/tests/unit/operation/overlayng/EdgeNodingBuilderTest.cpp
@@ -0,0 +1,110 @@
+//
+// Test Suite for geos::operation::overlayng::EdgeNodingBuilder class.
+
+#include <tut/tut.hpp>
+#include <utility.h>
+
+// geos
+#include <geos/geom/CircularString.h>
+#include <geos/algorithm/CircularArcIntersector.h>
+#include <geos/noding/ArcIntersectionAdder.h>
+#include <geos/noding/SimpleNoder.h>
+#include <geos/operation/overlayng/EdgeNodingBuilder.h>
+
+// std
+#include <memory>
+
+
+
+using namespace geos::geom;
+using namespace geos::noding;
+using namespace geos::operation::overlayng;
+using geos::algorithm::CircularArcIntersector;
+using geos::io::WKTReader;
+using geos::io::WKTWriter;
+
+namespace tut {
+struct test_edgenodingbuilder_data {
+    WKTReader reader_;
+
+    PrecisionModel pm_floating{PrecisionModel::Type::FLOATING};
+    GeometryFactory::Ptr factory_{GeometryFactory::create(&pm_floating)};
+
+    std::unique_ptr<Geometry> toGeometry(const Edge& edge) const
+    {
+        if (edge.isCurved()) {
+            return factory_->createCircularString(edge.getCoordinates());
+        }
+        return factory_->createLineString(edge.getCoordinates());
+    }
+
+    std::unique_ptr<Geometry> toGeometry(const std::vector<Edge*> edges) const
+    {
+        std::vector<std::unique_ptr<Geometry>> geoms;
+        for (const auto* edge : edges) {
+            geoms.push_back(toGeometry(*edge));
+        }
+        return factory_->createGeometryCollection(std::move(geoms));
+    }
+
+    void checkEdges(const std::string& wkt1, const std::string& wkt2, const std::string& wktExpected) const
+    {
+        auto geom1 = reader_.read(wkt1);
+        auto geom2 = reader_.read(wkt2);
+
+        SimpleNoder noder;
+        CircularArcIntersector cai;
+        ArcIntersectionAdder aia(cai);
+        noder.setArcIntersector(aia);
+
+        EdgeNodingBuilder builder(geom1->getPrecisionModel(), &noder);
+
+        auto edges = builder.build(geom1.get(), geom2.get());
+        std::unique_ptr<Geometry> expected = reader_.read(wktExpected);
+        ensure_equals_geometry_xyzm(toGeometry(edges).get(), expected.get(), 1e-5);
+    }
+};
+
+typedef test_group<test_edgenodingbuilder_data> group;
+typedef group::object object;
+
+group test_edgenodingbuilder_group("geos::operation::overlayng::EdgeNodingBuilder");
+
+template<>
+template<>
+void object::test<1>()
+{
+    set_test_name("two CircularStrings");
+
+    checkEdges(
+        "CIRCULARSTRING (0 0, 1 1, 2 0)",
+        "CIRCULARSTRING (0 1, 1 0, 2 1)",
+        "GEOMETRYCOLLECTION ("
+            "CIRCULARSTRING (0 0, 0.0340742 0.258819, 0.133975 0.5),"
+            "CIRCULARSTRING (0.133975 0.5, 1 1, 1.86603 0.5),"
+            "CIRCULARSTRING (1.86603 0.5, 1.96593 0.258819, 2 0),"
+            "CIRCULARSTRING (0 1, 0.0340742 0.741181, 0.133975 0.5),"
+            "CIRCULARSTRING (0.133975 0.5, 1 0, 1.86603 0.5),"
+            "CIRCULARSTRING (1.86603 0.5, 1.96593 0.741181, 2 1)"
+        ")");
+}
+
+template<>
+template<>
+void object::test<2>()
+{
+    set_test_name("CurvePolygon and LineString");
+
+    checkEdges("CURVEPOLYGON (COMPOUNDCURVE(CIRCULARSTRING (0 0, 1 1, 2 0), (2 0, 0 0)))",
+               "LINESTRING (1 0, 2 1)",
+         "GEOMETRYCOLLECTION ("
+                         "CIRCULARSTRING (0 0, 0.6173165676349103 0.9238795325112867, 1.7071067811865475 0.7071067811865475),"
+                         "CIRCULARSTRING (1.7071067811865475 0.7071067811865475, 1.9238795325112867 0.3826834323650898, 2 0),"
+                         "LINESTRING (1 0, 1.7071067811865475 0.7071067811865475),"
+                         "LINESTRING (1.7071067811865475 0.7071067811865475, 2 1),"
+                         "LINESTRING (0 0, 1 0),"
+                         "LINESTRING (1 0, 2 0)"
+                     ")");
+}
+
+}
diff --git a/tests/unit/operation/overlayng/OverlayGraphTest.cpp b/tests/unit/operation/overlayng/OverlayGraphTest.cpp
index e179702fe..7fce5ff72 100644
--- a/tests/unit/operation/overlayng/OverlayGraphTest.cpp
+++ b/tests/unit/operation/overlayng/OverlayGraphTest.cpp
@@ -52,7 +52,7 @@ struct test_overlaygraph_data {
         std::unique_ptr<CoordinateSequence> cs = line->getCoordinates();
 
         EdgeSourceInfo esi(0);
-        Edge e(std::move(cs), &esi);
+        Edge e(std::move(cs), &esi, false);
         std::unique_ptr<CoordinateSequence> pts = e.getCoordinates();
 
         graph->addEdge(&e);

-----------------------------------------------------------------------

Summary of changes:
 include/geos/algorithm/CircularArcs.h              |  15 ++
 include/geos/algorithm/PointLocator.h              |   6 +
 include/geos/geom/CircularArc.h                    |   2 +
 include/geos/geom/Curve.h                          |   2 +
 include/geos/operation/overlayng/Edge.h            |  42 ++--
 .../geos/operation/overlayng/EdgeNodingBuilder.h   |  43 +++-
 include/geos/operation/overlayng/LineBuilder.h     |   8 +-
 include/geos/operation/overlayng/OverlayEdge.h     |  10 +-
 include/geos/operation/overlayng/OverlayEdgeRing.h |  23 +-
 include/geos/operation/overlayng/OverlayGraph.h    |   4 +-
 .../geos/operation/overlayng/OverlayMixedPoints.h  |  17 +-
 include/geos/operation/overlayng/OverlayUtil.h     |  17 +-
 include/geos/operation/overlayng/PolygonBuilder.h  |   6 +-
 src/algorithm/CircularArcIntersector.cpp           | 162 +++++++-----
 src/algorithm/CircularArcs.cpp                     |  94 ++++---
 src/algorithm/PointLocator.cpp                     |  80 +++++-
 src/geom/CircularArc.cpp                           |  14 ++
 src/geom/Curve.cpp                                 |   6 +
 src/geom/GeometryFactory.cpp                       |  22 ++
 src/noding/NodableArcString.cpp                    | 243 +++++++++++++-----
 src/noding/snap/SnappingNoder.cpp                  |   3 +-
 src/operation/overlayng/Edge.cpp                   |   3 +-
 src/operation/overlayng/EdgeNodingBuilder.cpp      | 191 +++++++++++----
 .../overlayng/IndexedPointOnLineLocator.cpp        |   2 +-
 src/operation/overlayng/InputGeometry.cpp          |  20 +-
 src/operation/overlayng/LineBuilder.cpp            |  33 ++-
 src/operation/overlayng/OverlayEdgeRing.cpp        | 150 ++++++++----
 src/operation/overlayng/OverlayGraph.cpp           |  24 +-
 src/operation/overlayng/OverlayMixedPoints.cpp     |  40 +--
 src/operation/overlayng/OverlayNG.cpp              |   6 +-
 src/operation/overlayng/OverlayNGRobust.cpp        |   3 -
 src/operation/overlayng/OverlayUtil.cpp            |  39 ++-
 src/operation/overlayng/PolygonBuilder.cpp         |  10 +-
 .../unit/algorithm/CircularArcIntersectorTest.cpp  |  60 +++++
 tests/unit/capi/GEOSDifferenceTest.cpp             |   8 +-
 tests/unit/capi/GEOSIntersectionTest.cpp           |  10 +-
 tests/unit/capi/GEOSNodeTest.cpp                   |   8 +-
 tests/unit/capi/GEOSSymDifferenceTest.cpp          |  10 +-
 tests/unit/capi/GEOSUnionTest.cpp                  |  10 +-
 tests/unit/geom/CircularStringTest.cpp             |   8 +-
 tests/unit/geom/CompoundCurveTest.cpp              |   9 +-
 tests/unit/geom/CurvePolygonTest.cpp               |   8 +-
 tests/unit/geom/MultiCurveTest.cpp                 |   9 +-
 tests/unit/geom/MultiSurfaceTest.cpp               |   8 +-
 .../operation/overlayng/EdgeNodingBuilderTest.cpp  | 110 +++++++++
 .../unit/operation/overlayng/OverlayGraphTest.cpp  |   2 +-
 tests/unit/operation/overlayng/OverlayNGTest.cpp   | 271 ++++++++++++++++++++-
 47 files changed, 1453 insertions(+), 418 deletions(-)
 create mode 100644 tests/unit/operation/overlayng/EdgeNodingBuilderTest.cpp


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From git at osgeo.org  Tue Jun 16 11:36:50 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue, 16 Jun 2026 11:36:50 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 ce51dbd1f94661b99ae8b263e56b6c53cc7876ae
Message-ID: <20260616183654.7F01F1A1C7E@trac.osgeo.org>

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the project "GEOS".

The branch, main has been updated
       via  ce51dbd1f94661b99ae8b263e56b6c53cc7876ae (commit)
      from  11f1851a82bdf5f9983f03d1b967adfb5da6fb39 (commit)

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- Log -----------------------------------------------------------------
commit ce51dbd1f94661b99ae8b263e56b6c53cc7876ae
Author: Daniel Baston <dbaston at gmail.com>
Date:   Tue Jun 16 14:36:04 2026 -0400

    NEWS updates

diff --git a/NEWS.md b/NEWS.md
index cb455468c..a77954ff6 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -7,6 +7,16 @@
   - Add GEOSCoverageEdges (Paul Ramsey)
   - Add new C API functions for Hausdorff distance (GH-1352, Sven Jensen)
   - Add GEOSSubdivideByGrid (GH-1232, Dan Baston)
+  - Add support for curved geometries to the following operations:
+    - BoundaryOp (GH-1394, Dan Baston)
+    - DistanceOp (GH-1428, Dan Baston)
+    - GeometryNoder (GH-1347, Dan Baston)
+    - GeometryPrecisionReducer (pointwise only, GH-1402; Dan Baston)
+    - LineMerger (GH-1441, Dan Baston)
+    - Normalize (GH-1397, Dan Baston)
+    - OverlayNG (GH-1427, Dan Baston)
+    - Polygonizer (GH-1420, Dan Baston)
+  - Add GeometrySplitter (GH-1424, Dan Baston)
 
 - Breaking Changes:
   - BufferOp returns POLYGON EMPTY when fed Inf/Nan coords (GH-1332)
@@ -21,11 +31,12 @@
   - Preserve M values in GEOSDensify (GH-1319, Dan Baston)
   - Preserve M values in GEOSSimplify (GH-1317, Dan Baston)
   - Preserve M values in GEOSPolygonize (GH-1363 Dan Baston)
-  - Fix some cases of dropped M values in overlay (GH-1364/GH-1388, Dan Baston)
+  - Fix some cases of dropped M values in overlay (GH-1364,GH-1388,GH-1407,GH-1408; Dan Baston)
   - Support curved inputs in GEOSNode (GH-1347, Dan Baston)
   - GEOSClusterDBSCAN fix unsassigned clusters with minPoints <= 1 (GH-1386, Dan Baston)
   - Fix crash in GEOSConvexHull (GH-1358, Dan Baston)
   - Overlay performance improvements (GH-1353, arriopolis, Martin Davis)
+  - Fix unintended ring rotation in Overlay results (GH-1412, Dan Baston)
 
 ## Changes in 3.14.0
 2025-08-21

-----------------------------------------------------------------------

Summary of changes:
 NEWS.md | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)


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From git at osgeo.org  Tue Jun 16 18:40:12 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue, 16 Jun 2026 18:40:12 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch 3.14 updated.
 a80d3c2da06305ce5d6cf03b882c2809c5ee43ab
Message-ID: <20260617014013.28CBE1A5E21@trac.osgeo.org>

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       via  a80d3c2da06305ce5d6cf03b882c2809c5ee43ab (commit)
      from  a7a985eca203a98c19b36641ac29bdbac1c9db31 (commit)

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- Log -----------------------------------------------------------------
commit a80d3c2da06305ce5d6cf03b882c2809c5ee43ab
Author: Daniel Baston <dbaston at gmail.com>
Date:   Tue Jun 16 21:39:44 2026 -0400

    NEWS update

diff --git a/NEWS.md b/NEWS.md
index a60c7ad58..b1bea0c64 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -10,6 +10,7 @@
   - Fix crash in GEOSConvexHull (GH-1358, Dan Baston)
   - Guard against stack overflow in inputs (GH-1437, Paul Ramsey)
   - Avoid overflow risk in WKB reader (Paul Ramsey)
+  - GEOSNode: fix crash on collection with empty components (GH-1406, Dan Baston)
 
 ## Changes in 3.14.1
 2025-10-27

-----------------------------------------------------------------------

Summary of changes:
 NEWS.md | 1 +
 1 file changed, 1 insertion(+)


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From git at osgeo.org  Tue Jun 16 19:39:53 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue, 16 Jun 2026 19:39:53 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 69b6dad8aa171142b2e0d4342b578232f40cd9a4
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commit 69b6dad8aa171142b2e0d4342b578232f40cd9a4
Author: Daniel Baston <dbaston at gmail.com>
Date:   Tue Jun 16 22:03:30 2026 -0400

    NodableSegmentString constructor: accept pts as const ref

diff --git a/include/geos/noding/NodableSegmentString.h b/include/geos/noding/NodableSegmentString.h
index 7b3440d95..8865c0781 100644
--- a/include/geos/noding/NodableSegmentString.h
+++ b/include/geos/noding/NodableSegmentString.h
@@ -37,7 +37,7 @@ class GEOS_DLL NodableSegmentString : public SegmentString {
 private:
 protected:
 public:
-    NodableSegmentString(const void* newContext, std::shared_ptr<const geom::CoordinateSequence> newSeq)
+    NodableSegmentString(const void* newContext, const std::shared_ptr<const geom::CoordinateSequence>& newSeq)
         :
         SegmentString(newContext, newSeq)
     { }

-----------------------------------------------------------------------

Summary of changes:
 include/geos/noding/NodableSegmentString.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)


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From git at osgeo.org  Wed Jun 17 09:45:40 2026
From: git at osgeo.org (git at osgeo.org)
Date: Wed, 17 Jun 2026 09:45:40 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 fa569a231414a1f73cb6c4f3c31c259700337035
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- Log -----------------------------------------------------------------
commit fa569a231414a1f73cb6c4f3c31c259700337035
Author: Daniel Baston <dbaston at gmail.com>
Date:   Wed Jun 17 10:59:48 2026 -0400

    KdTree: Resolve various clang-tidy issues

diff --git a/include/geos/index/kdtree/KdNodeVisitor.h b/include/geos/index/kdtree/KdNodeVisitor.h
index 17c9a9cfa..51589e4f5 100644
--- a/include/geos/index/kdtree/KdNodeVisitor.h
+++ b/include/geos/index/kdtree/KdNodeVisitor.h
@@ -35,6 +35,7 @@ public:
     KdNodeVisitor() {};
     virtual void visit(KdNode *node) = 0;
 
+    virtual ~KdNodeVisitor() = default;
 
 };
 
diff --git a/include/geos/index/kdtree/KdTree.h b/include/geos/index/kdtree/KdTree.h
index 144fbc13f..f98f203cc 100644
--- a/include/geos/index/kdtree/KdTree.h
+++ b/include/geos/index/kdtree/KdTree.h
@@ -19,9 +19,7 @@
 #include <geos/index/kdtree/KdNodeVisitor.h>
 #include <geos/index/kdtree/KdNode.h>
 
-#include <memory>
 #include <vector>
-#include <string>
 #include <deque>
 
 #ifdef _MSC_VER
@@ -64,8 +62,8 @@ private:
     KdNode* findBestMatchNode(const geom::Coordinate& p);
     KdNode* insertExact(const geom::Coordinate& p, void* data);
 
-    void queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd, KdNodeVisitor& visitor);
-    KdNode* queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, bool odd);
+    static void queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd, KdNodeVisitor& visitor);
+    static KdNode* queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, bool odd);
 
     /**
     * Create a node on a locally managed deque to allow easy
@@ -85,15 +83,16 @@ private:
         KdNode* getNode();
         void visit(KdNode* node) override;
 
+        // Declare type as noncopyable
+        BestMatchVisitor(const BestMatchVisitor& other) = delete;
+        BestMatchVisitor& operator=(const BestMatchVisitor& rhs) = delete;
+
     private:
         // Members
         double tolerance;
         KdNode* matchNode;
         double matchDist;
         const geom::Coordinate& p;
-        // Declare type as noncopyable
-        BestMatchVisitor(const BestMatchVisitor& other);
-        BestMatchVisitor& operator=(const BestMatchVisitor& rhs);
     };
 
     /**
@@ -102,16 +101,17 @@ private:
     */
     class AccumulatingVisitor : public KdNodeVisitor {
     public:
-        AccumulatingVisitor(std::vector<KdNode*>& p_nodeList) :
+        explicit AccumulatingVisitor(std::vector<KdNode*>& p_nodeList) :
             nodeList(p_nodeList) {};
         void visit(KdNode* node) override { nodeList.push_back(node); }
 
+        // Declare type as noncopyable
+        AccumulatingVisitor(const AccumulatingVisitor& other) = delete;
+        AccumulatingVisitor& operator=(const AccumulatingVisitor& rhs) = delete;
+
     private:
         // Members
         std::vector<KdNode*>& nodeList;
-        // Declare type as noncopyable
-        AccumulatingVisitor(const AccumulatingVisitor& other);
-        AccumulatingVisitor& operator=(const AccumulatingVisitor& rhs);
     };
 
 
@@ -121,10 +121,10 @@ public:
     /**
     * Converts a collection of {@link KdNode}s to an vector of {@link geom::Coordinate}s.
     *
-    * @param kdnodes a collection of nodes
-    * @return an vector of the coordinates represented by the nodes
+    * @param kdNodes a collection of nodes
+    * @return a vector of the coordinates represented by the nodes
     */
-    static std::unique_ptr<std::vector<geom::Coordinate>> toCoordinates(std::vector<KdNode*>& kdnodes);
+    static std::vector<geom::Coordinate> toCoordinates(const std::vector<KdNode*>& kdNodes);
 
     /**
     * Converts a collection of {@link KdNode}s
@@ -132,12 +132,12 @@ public:
     * specifying whether repeated nodes should be represented
     * by multiple coordinates.
     *
-    * @param kdnodes a collection of nodes
+    * @param kdNodes a collection of nodes
     * @param includeRepeated true if repeated nodes should
     *   be included multiple times
-    * @return an vector of the coordinates represented by the nodes
+    * @return a vector of the coordinates represented by the nodes
     */
-    static std::unique_ptr<std::vector<geom::Coordinate>> toCoordinates(std::vector<KdNode*>& kdnodes, bool includeRepeated);
+    static std::vector<geom::Coordinate> toCoordinates(const std::vector<KdNode*>& kdNodes, bool includeRepeated);
 
     KdTree() :
         root(nullptr),
@@ -145,7 +145,7 @@ public:
         tolerance(0.0)
         {};
 
-    KdTree(double p_tolerance) :
+    explicit KdTree(double p_tolerance) :
         root(nullptr),
         numberOfNodes(0),
         tolerance(p_tolerance)
@@ -167,7 +167,7 @@ public:
     /**
     * Performs a range search of the points in the index.
     */
-    std::unique_ptr<std::vector<KdNode*>> query(const geom::Envelope& queryEnv);
+    std::vector<KdNode*> query(const geom::Envelope& queryEnv);
 
     /**
     * Performs a range search of the points in the index.
diff --git a/src/index/kdtree/KdTree.cpp b/src/index/kdtree/KdTree.cpp
index a0c2dfbff..2118165aa 100644
--- a/src/index/kdtree/KdTree.cpp
+++ b/src/index/kdtree/KdTree.cpp
@@ -27,26 +27,26 @@ namespace kdtree { // geos.index.kdtree
 
 
 /*public static*/
-std::unique_ptr<std::vector<Coordinate>>
-KdTree::toCoordinates(std::vector<KdNode*>& kdnodes)
+std::vector<Coordinate>
+KdTree::toCoordinates(const std::vector<KdNode*>& kdnodes)
 {
     return toCoordinates(kdnodes, false);
 }
 
 /*public static*/
-std::unique_ptr<std::vector<Coordinate>>
-KdTree::toCoordinates(std::vector<KdNode*>& kdnodes, bool includeRepeated)
+std::vector<Coordinate>
+KdTree::toCoordinates(const std::vector<KdNode*>& kdnodes, bool includeRepeated)
 {
-    std::unique_ptr<std::vector<Coordinate>> coord(new std::vector<Coordinate>);
+    std::vector<Coordinate> coord;
     for (auto node: kdnodes) {
         std::size_t count = includeRepeated ? node->getCount() : 1;
         for (std::size_t i = 0; i < count; i++) {
-            coord->emplace_back(node->getCoordinate());
+            coord.emplace_back(node->getCoordinate());
         }
     }
     if (!includeRepeated) {
         // Remove duplicate Coordinates from coordList
-        coord->erase(std::unique(coord->begin(), coord->end()), coord->end());
+        coord.erase(std::unique(coord.begin(), coord.end()), coord.end());
     }
     return coord;
 }
@@ -153,7 +153,7 @@ KdTree::insertExact(const geom::Coordinate& p, void* data)
 void
 KdTree::queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd, KdNodeVisitor& visitor)
 {
-    // Non recursive formulation of in-order traversal from
+    // Non-recursive formulation of in-order traversal from
     // http://web.cs.wpi.edu/~cs2005/common/iterative.inorder
     // Otherwise we may blow up the stack
     // See https://github.com/qgis/QGIS/issues/45226
@@ -175,7 +175,7 @@ KdTree::queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd,
             }
             bool searchLeft = min < discriminant;
 
-            activeNodes.emplace(Pair(currentNode, odd));
+            activeNodes.emplace(currentNode, odd);
 
             // search is computed via in-order traversal
             KdNode* leftNode = nullptr;
@@ -267,11 +267,11 @@ KdTree::query(const geom::Envelope& queryEnv, KdNodeVisitor& visitor)
 }
 
 /*public*/
-std::unique_ptr<std::vector<KdNode*>>
+std::vector<KdNode*>
 KdTree::query(const geom::Envelope& queryEnv)
 {
-    std::unique_ptr<std::vector<KdNode*>> result(new std::vector<KdNode*>);
-    query(queryEnv, *result);
+    std::vector<KdNode*> result;
+    query(queryEnv, result);
     return result;
 }
 
diff --git a/tests/unit/index/kdtree/KdTreeTest.cpp b/tests/unit/index/kdtree/KdTreeTest.cpp
index 2de94f162..34ef8d8c6 100644
--- a/tests/unit/index/kdtree/KdTreeTest.cpp
+++ b/tests/unit/index/kdtree/KdTreeTest.cpp
@@ -28,13 +28,13 @@ struct test_kdtree_data {
         std::vector<Coordinate> expectedCoord;
         csExpected->toVector(expectedCoord);
         // Read tree into vector of coordinates
-        std::unique_ptr<std::vector<Coordinate>> result = KdTree::toCoordinates(*(index.query(queryEnv)), includeRepeated);
+        auto result = KdTree::toCoordinates(index.query(queryEnv), includeRepeated);
 
-        std::sort(result->begin(), result->end());
+        std::sort(result.begin(), result.end());
         std::sort(expectedCoord.begin(), expectedCoord.end());
 
-        ensure("Result count not equal to expected count", result->size() == expectedCoord.size());
-        ensure("Expected result coordinates not found", *result == expectedCoord);
+        ensure("Result count not equal to expected count", result.size() == expectedCoord.size());
+        ensure("Expected result coordinates not found", result == expectedCoord);
     }
 
     void testQuery(std::string& wktInput, double tolerance, const Envelope& queryEnv, std::string& wktExpected) {
@@ -67,11 +67,11 @@ void object::test<1> ()
     ensure("Inserting 2 identical points should create one node", node1 == node2);
 
     Envelope queryEnv(0, 10, 0, 10);
-    std::unique_ptr<std::vector<KdNode*>> result = index.query(queryEnv);
+    std::vector<KdNode*> result = index.query(queryEnv);
 
-    ensure("query should return 1 result", result->size() == 1);
+    ensure("query should return 1 result", result.size() == 1);
 
-    KdNode* node = result->at(0);
+    KdNode* node = result.at(0);
     ensure("node should have two entries", node->getCount() == 2);
     ensure("node should be repeated", node->isRepeated());
 }
@@ -180,11 +180,11 @@ void object::test<8> ()
     ensure("Inserting 2 identical points should create one node", node1 == node2);
 
     Envelope queryEnv(0, 10, 0, 10);
-    std::unique_ptr<std::vector<KdNode*>> result = index.query(queryEnv);
+    std::vector<KdNode*> result = index.query(queryEnv);
 
-    ensure(result->size() == 1);
+    ensure(result.size() == 1);
 
-    KdNode* node = (KdNode*)(*result)[0];
+    KdNode* node = result[0];
     ensure(node->getCount() == 2);
     ensure(node->isRepeated());
 }

-----------------------------------------------------------------------

Summary of changes:
 include/geos/index/kdtree/KdNodeVisitor.h |  1 +
 include/geos/index/kdtree/KdTree.h        | 38 +++++++++++++++----------------
 src/index/kdtree/KdTree.cpp               | 24 +++++++++----------
 tests/unit/index/kdtree/KdTreeTest.cpp    | 20 ++++++++--------
 4 files changed, 42 insertions(+), 41 deletions(-)


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GEOS

From git at osgeo.org  Wed Jun 17 11:16:35 2026
From: git at osgeo.org (git at osgeo.org)
Date: Wed, 17 Jun 2026 11:16:35 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 3ffdc29d3973d77d2b3505557ed793b3c4ca8111
Message-ID: <20260617181635.C4EF11B1985@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
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The branch, main has been updated
       via  3ffdc29d3973d77d2b3505557ed793b3c4ca8111 (commit)
      from  fa569a231414a1f73cb6c4f3c31c259700337035 (commit)

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- Log -----------------------------------------------------------------
commit 3ffdc29d3973d77d2b3505557ed793b3c4ca8111
Author: Daniel Baston <dbaston at gmail.com>
Date:   Wed Jun 17 14:16:15 2026 -0400

    CommonBits: clean UBSAN error (#1448)

diff --git a/src/precision/CommonBits.cpp b/src/precision/CommonBits.cpp
index e5d004ebb..179e0d557 100644
--- a/src/precision/CommonBits.cpp
+++ b/src/precision/CommonBits.cpp
@@ -14,6 +14,7 @@
  **********************************************************************/
 
 #include <geos/precision/CommonBits.h>
+#include <limits>
 
 namespace geos {
 namespace precision { // geos.precision
@@ -71,6 +72,11 @@ CommonBits::CommonBits()
 void
 CommonBits::add(double num)
 {
+    if (num > static_cast<double>(std::numeric_limits<std::int64_t>::max())) {
+        commonBits = 0;
+        return;
+    }
+
     int64_t numBits = (int64_t) num;
     if(isFirst) {
         commonBits = numBits;

-----------------------------------------------------------------------

Summary of changes:
 src/precision/CommonBits.cpp | 6 ++++++
 1 file changed, 6 insertions(+)


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From git at osgeo.org  Wed Jun 17 12:36:00 2026
From: git at osgeo.org (git at osgeo.org)
Date: Wed, 17 Jun 2026 12:36:00 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 4150b856e18b4f33460dbe12b23eea449af8095b
Message-ID: <20260617193600.EE3771B28BC@trac.osgeo.org>

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The branch, main has been updated
       via  4150b856e18b4f33460dbe12b23eea449af8095b (commit)
      from  3ffdc29d3973d77d2b3505557ed793b3c4ca8111 (commit)

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- Log -----------------------------------------------------------------
commit 4150b856e18b4f33460dbe12b23eea449af8095b
Author: Sandro Santilli <strk at kbt.io>
Date:   Wed Jun 17 21:35:42 2026 +0200

    Ensure rpath is used for libgeos_c.so (#1436)
    
    * Ensure rpath is used for libgeos_c.so
    
    This ensures each C library links to its corresponding C++ library
    
    Closes GH-1435
    
    * Allow CMAKE_INSTALL_RPATH override from commandline, handle MacOS

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d114245cf..541288b93 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -406,6 +406,18 @@ if(BUILD_SHARED_LIBS)
     PRIVATE $<$<BOOL:${WIN32}>:GEOS_DLL_EXPORT>)
 
   set_target_properties(geos_c PROPERTIES VERSION ${CAPI_VERSION})
+
+  # See https://github.com/libgeos/geos/issues/1435
+  if(NOT DEFINED CMAKE_INSTALL_RPATH)
+    # Use relative rpath
+    if(APPLE)
+      set_target_properties(geos_c PROPERTIES
+        INSTALL_RPATH "@loader_path")
+    else()
+      set_target_properties(geos_c PROPERTIES INSTALL_RPATH "\$ORIGIN")
+    endif()
+  endif()
+
   if(NOT WIN32 OR MINGW)
     set_target_properties(geos_c PROPERTIES SOVERSION ${CAPI_VERSION_MAJOR})
   endif()

-----------------------------------------------------------------------

Summary of changes:
 CMakeLists.txt | 12 ++++++++++++
 1 file changed, 12 insertions(+)


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From git at osgeo.org  Wed Jun 17 14:04:31 2026
From: git at osgeo.org (git at osgeo.org)
Date: Wed, 17 Jun 2026 14:04:31 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 cc58aad27d8e8d13fcfcfab00b1305944c6833e7
Message-ID: <20260617210431.D73581B3171@trac.osgeo.org>

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      from  4150b856e18b4f33460dbe12b23eea449af8095b (commit)

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- Log -----------------------------------------------------------------
commit cc58aad27d8e8d13fcfcfab00b1305944c6833e7
Author: Kurt Schwehr <schwehr at gmail.com>
Date:   Wed Jun 17 14:04:09 2026 -0700

    Fix `size_t <<` debug prints (#1452)
    
    Bug introduced in https://github.com/libgeos/geos/commit/d271aaa9a1939fe5a51c5b5d05f1a3d547a2f900

diff --git a/src/io/WKBReader.cpp b/src/io/WKBReader.cpp
index b366d91b9..3562e0147 100644
--- a/src/io/WKBReader.cpp
+++ b/src/io/WKBReader.cpp
@@ -46,6 +46,9 @@
 
 //#define DEBUG_WKB_READER 1
 
+#if DEBUG_WKB_READER
+#include <iostream>
+#endif
 
 using namespace geos::geom;
 
@@ -174,7 +177,7 @@ WKBReader::readHEX(std::istream& is)
             static_cast<unsigned char>((result_high << 4) + result_low);
 
 #if DEBUG_HEX_READER
-        std::size_t << "HEX " << high << low << " -> DEC " << (int)value << std::endl;
+        std::cout << "HEX " << high << low << " -> DEC " << (int)value << std::endl;
 #endif
         // write the value to the output stream
         os << value;
@@ -272,7 +275,7 @@ WKBReader::readGeometry()
     unsigned char byteOrder = dis.readByte();
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB byteOrder: " << (int)byteOrder << std::endl;
+    std::cout << "WKB byteOrder: " << (int)byteOrder << std::endl;
 #endif
 
     // default is machine endian
@@ -295,7 +298,7 @@ WKBReader::readGeometry()
     int sfsqlHasM = (typeInt & 0x40000000) != 0;
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB geometryType: " << geometryType << std::endl;
+    std::cout << "WKB geometryType: " << geometryType << std::endl;
 #endif
 
     hasZ = sfsqlHasZ || isoHasZ;
@@ -311,17 +314,17 @@ WKBReader::readGeometry()
     }
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB hasZ: " << hasZ << std::endl;
+    std::cout << "WKB hasZ: " << hasZ << std::endl;
 #endif
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB dimensions: " << inputDimension << std::endl;
+    std::cout << "WKB dimensions: " << inputDimension << std::endl;
 #endif
 
     bool hasSRID = ((typeInt & 0x20000000) != 0);
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB hasSRID: " << hasSRID << std::endl;
+    std::cout << "WKB hasSRID: " << hasSRID << std::endl;
 #endif
 
     int SRID = 0;
@@ -398,7 +401,7 @@ WKBReader::readLineString()
     uint32_t size = dis.readUnsigned();
     minMemSize(GEOS_LINESTRING, size);
 #if DEBUG_WKB_READER
-    std::size_t << "WKB npoints: " << size << std::endl;
+    std::cout << "WKB npoints: " << size << std::endl;
 #endif
     auto pts = readCoordinateSequence(size);
     return factory.createLineString(std::move(pts));
@@ -410,7 +413,7 @@ WKBReader::readLinearRing()
     uint32_t size = dis.readUnsigned();
     minMemSize(GEOS_LINEARRING, size);
 #if DEBUG_WKB_READER
-    std::size_t << "WKB npoints: " << size << std::endl;
+    std::cout << "WKB npoints: " << size << std::endl;
 #endif
     auto pts = readCoordinateSequence(size);
     // Replace unclosed ring with closed
@@ -451,7 +454,7 @@ WKBReader::readPolygon()
     minMemSize(GEOS_POLYGON, numRings);
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB numRings: " << numRings << std::endl;
+    std::cout << "WKB numRings: " << numRings << std::endl;
 #endif
 
     std::unique_ptr<LinearRing> shell;
@@ -481,7 +484,7 @@ WKBReader::readCurvePolygon()
     minMemSize(GEOS_POLYGON, numRings);
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB numRings: " << numRings << std::endl;
+    std::cout << "WKB numRings: " << numRings << std::endl;
 #endif
 
     if (numRings == 0) {
@@ -624,7 +627,7 @@ WKBReader::readCoordinate()
         }
     }
 #if DEBUG_WKB_READER
-    std::size_t << "WKB coordinate: " << ordValues[0] << "," << ordValues[1] << std::endl;
+    std::cout << "WKB coordinate: " << ordValues[0] << "," << ordValues[1] << std::endl;
 #endif
 }
 
diff --git a/src/io/WKBWriter.cpp b/src/io/WKBWriter.cpp
index f7c83d38d..95c64b044 100644
--- a/src/io/WKBWriter.cpp
+++ b/src/io/WKBWriter.cpp
@@ -42,6 +42,10 @@
 
 #undef DEBUG_WKB_WRITER
 
+#if DEBUG_WKB_READER
+#include <iostream>
+#endif
+
 
 using namespace geos::geom;
 
@@ -380,7 +384,7 @@ void
 WKBWriter::writeCoordinate(const CoordinateSequence& cs, std::size_t idx)
 {
 #if DEBUG_WKB_WRITER
-    std::size_t << "writeCoordinate: X:" << cs.getX(idx) << " Y:" << cs.getY(idx) << std::endl;
+    std::cout << "writeCoordinate: X:" << cs.getX(idx) << " Y:" << cs.getY(idx) << std::endl;
 #endif
     assert(outStream);
 
@@ -442,4 +446,3 @@ WKBWriter::getWkbType(const Geometry& g) {
 
 } // namespace geos.io
 } // namespace geos
-
diff --git a/src/operation/overlay/snap/GeometrySnapper.cpp b/src/operation/overlay/snap/GeometrySnapper.cpp
index c0b429739..a9a4722e6 100644
--- a/src/operation/overlay/snap/GeometrySnapper.cpp
+++ b/src/operation/overlay/snap/GeometrySnapper.cpp
@@ -209,8 +209,8 @@ GeometrySnapper::snap(const geom::Geometry& g0,
     GeometrySnapper snapper1(g1);
     snapGeom.second = snapper1.snapTo(*snapGeom.first, snapTolerance);
 
-//	std::size_t << *snapGeom.first << std::endl;
-//	std::size_t << *snapGeom.second << std::endl;
+//	std::cout << *snapGeom.first << std::endl;
+//	std::cout << *snapGeom.second << std::endl;
 
 }
 
@@ -228,4 +228,3 @@ GeometrySnapper::snapToSelf(const geom::Geometry& g,
 } // namespace geos.operation.overlay
 } // namespace geos.operation
 } // namespace geos
-

-----------------------------------------------------------------------

Summary of changes:
 src/io/WKBReader.cpp                           | 25 ++++++++++++++-----------
 src/io/WKBWriter.cpp                           |  7 +++++--
 src/operation/overlay/snap/GeometrySnapper.cpp |  5 ++---
 3 files changed, 21 insertions(+), 16 deletions(-)


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From git at osgeo.org  Fri Jun 19 06:59:52 2026
From: git at osgeo.org (git at osgeo.org)
Date: Fri, 19 Jun 2026 06:59:52 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 4226b5a034d249e64385d3dac7e69774ff30d6f3
Message-ID: <20260619135952.C04711B12E8@trac.osgeo.org>

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       via  b0689cbf1ac4f21c9370e8485aae39c8a55d9c47 (commit)
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- Log -----------------------------------------------------------------
commit 4226b5a034d249e64385d3dac7e69774ff30d6f3
Author: Daniel Baston <dbaston at gmail.com>
Date:   Thu Jun 18 12:49:34 2026 -0400

    KdTree: Disable optimizations in latest MSVC version
    
    References #1449

diff --git a/src/index/kdtree/KdTree.cpp b/src/index/kdtree/KdTree.cpp
index 2118165aa..e11626aed 100644
--- a/src/index/kdtree/KdTree.cpp
+++ b/src/index/kdtree/KdTree.cpp
@@ -226,6 +226,11 @@ KdTree::queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd,
     }
 }
 
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+// Avoid segfault with MSVC 19.51.36246.0
+// See https://github.com/libgeos/geos/issues/1449
+#pragma optimize("", off)
+#endif
 /*private*/
 KdNode*
 KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, bool odd)
@@ -257,7 +262,9 @@ KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, boo
     }
     return nullptr;
 }
-
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+#pragma optimize("", on)
+#endif
 
 /*public*/
 void

commit b0689cbf1ac4f21c9370e8485aae39c8a55d9c47
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri Jun 19 09:24:45 2026 -0400

    KdTree: Add minimal test for #1449

diff --git a/tests/unit/index/kdtree/KdTreeTest.cpp b/tests/unit/index/kdtree/KdTreeTest.cpp
index 34ef8d8c6..ec8d238e7 100644
--- a/tests/unit/index/kdtree/KdTreeTest.cpp
+++ b/tests/unit/index/kdtree/KdTreeTest.cpp
@@ -189,6 +189,24 @@ void object::test<8> ()
     ensure(node->isRepeated());
 }
 
+template<>
+template<>
+void object::test<9>()
+{
+    set_test_name("query by point");
+    // minimal test for https://github.com/libgeos/geos/issues/1449
+
+    KdTree index;
+    ensure(index.query({ 6, 8 }) == nullptr);
+
+    const KdNode* node68 = index.insert({ 6, 8 });
+    ensure(node68);
+    ensure_equals(index.query({ 6, 8 }), node68);
+
+    const KdNode* node28 = index.insert({ 2, 8 });
+    ensure(node28);
+    ensure_equals(index.query({ 2, 8 }), node28);
+}
 
 
 

-----------------------------------------------------------------------

Summary of changes:
 src/index/kdtree/KdTree.cpp            |  9 ++++++++-
 tests/unit/index/kdtree/KdTreeTest.cpp | 18 ++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)


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From git at osgeo.org  Fri Jun 19 14:57:18 2026
From: git at osgeo.org (git at osgeo.org)
Date: Fri, 19 Jun 2026 14:57:18 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 b7e11f5710ace681562228b791651bbc28835986
Message-ID: <20260619215718.9088E1B866C@trac.osgeo.org>

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- Log -----------------------------------------------------------------
commit b7e11f5710ace681562228b791651bbc28835986
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri Jun 19 15:13:34 2026 -0400

    KdNode: mark some methods as const

diff --git a/include/geos/index/kdtree/KdNode.h b/include/geos/index/kdtree/KdNode.h
index e1238ab0b..1d7ea0450 100644
--- a/include/geos/index/kdtree/KdNode.h
+++ b/include/geos/index/kdtree/KdNode.h
@@ -42,15 +42,15 @@ public:
     KdNode(double p_x, double p_y, void* p_data);
     KdNode(const geom::Coordinate& p_p, void* p_data);
 
-    double getX() { return p.x; }
-    double getY() { return p.y; }
-    const geom::Coordinate& getCoordinate() { return p; }
+    double getX() const { return p.x; }
+    double getY() const { return p.y; }
+    const geom::Coordinate& getCoordinate() const { return p; }
     void* getData() { return data; }
     KdNode* getLeft() { return left; }
     KdNode* getRight() { return right; }
     void increment() { count++; }
-    std::size_t getCount() { return count; }
-    bool isRepeated() { return count > 1; }
+    std::size_t getCount() const { return count; }
+    bool isRepeated() const { return count > 1; }
     void setLeft(KdNode* p_left) { left = p_left; }
     void setRight(KdNode* p_right) { right = p_right; }
 
diff --git a/include/geos/index/kdtree/KdTree.h b/include/geos/index/kdtree/KdTree.h
index f98f203cc..a715a4c4c 100644
--- a/include/geos/index/kdtree/KdTree.h
+++ b/include/geos/index/kdtree/KdTree.h
@@ -119,7 +119,7 @@ private:
 public:
 
     /**
-    * Converts a collection of {@link KdNode}s to an vector of {@link geom::Coordinate}s.
+    * Converts a collection of {@link KdNode}s to a vector of {@link geom::Coordinate}s.
     *
     * @param kdNodes a collection of nodes
     * @return a vector of the coordinates represented by the nodes
@@ -128,7 +128,7 @@ public:
 
     /**
     * Converts a collection of {@link KdNode}s
-    * to an vector of {@link geom::Coordinate}s,
+    * to a vector of {@link geom::Coordinate}s,
     * specifying whether repeated nodes should be represented
     * by multiple coordinates.
     *

-----------------------------------------------------------------------

Summary of changes:
 include/geos/index/kdtree/KdNode.h | 10 +++++-----
 include/geos/index/kdtree/KdTree.h |  4 ++--
 2 files changed, 7 insertions(+), 7 deletions(-)


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From git at osgeo.org  Fri Jun 19 15:21:34 2026
From: git at osgeo.org (git at osgeo.org)
Date: Fri, 19 Jun 2026 15:21:34 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch 3.14 updated.
 70f292941d2e2243f2db66cf1292bfcffcc001fb
Message-ID: <20260619222135.0DBDE1B97E5@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
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The branch, 3.14 has been updated
       via  70f292941d2e2243f2db66cf1292bfcffcc001fb (commit)
       via  64e97b299d3f08160debd796c629fd7075b57892 (commit)
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- Log -----------------------------------------------------------------
commit 70f292941d2e2243f2db66cf1292bfcffcc001fb
Author: Daniel Baston <dbaston at gmail.com>
Date:   Thu Jun 18 12:49:34 2026 -0400

    KdTree: Disable optimizations in latest MSVC version
    
    References #1449

diff --git a/src/index/kdtree/KdTree.cpp b/src/index/kdtree/KdTree.cpp
index a0c2dfbff..9142a0789 100644
--- a/src/index/kdtree/KdTree.cpp
+++ b/src/index/kdtree/KdTree.cpp
@@ -226,6 +226,11 @@ KdTree::queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd,
     }
 }
 
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+// Avoid segfault with MSVC 19.51.36246.0
+// See https://github.com/libgeos/geos/issues/1449
+#pragma optimize("", off)
+#endif
 /*private*/
 KdNode*
 KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, bool odd)
@@ -257,7 +262,9 @@ KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, boo
     }
     return nullptr;
 }
-
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+#pragma optimize("", on)
+#endif
 
 /*public*/
 void

commit 64e97b299d3f08160debd796c629fd7075b57892
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri Jun 19 09:24:45 2026 -0400

    KdTree: Add minimal test for #1449

diff --git a/tests/unit/index/kdtree/KdTreeTest.cpp b/tests/unit/index/kdtree/KdTreeTest.cpp
index 2de94f162..1121ca25b 100644
--- a/tests/unit/index/kdtree/KdTreeTest.cpp
+++ b/tests/unit/index/kdtree/KdTreeTest.cpp
@@ -189,6 +189,24 @@ void object::test<8> ()
     ensure(node->isRepeated());
 }
 
+template<>
+template<>
+void object::test<9>()
+{
+    set_test_name("query by point");
+    // minimal test for https://github.com/libgeos/geos/issues/1449
+
+    KdTree index;
+    ensure(index.query({ 6, 8 }) == nullptr);
+
+    const KdNode* node68 = index.insert({ 6, 8 });
+    ensure(node68);
+    ensure_equals(index.query({ 6, 8 }), node68);
+
+    const KdNode* node28 = index.insert({ 2, 8 });
+    ensure(node28);
+    ensure_equals(index.query({ 2, 8 }), node28);
+}
 
 
 

commit b7ec1cbad96d0f518badeac697da4ab3381a86da
Author: Kurt Schwehr <schwehr at gmail.com>
Date:   Wed Jun 17 14:04:09 2026 -0700

    Fix `size_t <<` debug prints (#1452)
    
    Bug introduced in https://github.com/libgeos/geos/commit/d271aaa9a1939fe5a51c5b5d05f1a3d547a2f900

diff --git a/src/io/WKBReader.cpp b/src/io/WKBReader.cpp
index 442d28506..0016e6328 100644
--- a/src/io/WKBReader.cpp
+++ b/src/io/WKBReader.cpp
@@ -46,6 +46,9 @@
 
 //#define DEBUG_WKB_READER 1
 
+#if DEBUG_WKB_READER
+#include <iostream>
+#endif
 
 using namespace geos::geom;
 
@@ -174,7 +177,7 @@ WKBReader::readHEX(std::istream& is)
             static_cast<unsigned char>((result_high << 4) + result_low);
 
 #if DEBUG_HEX_READER
-        std::size_t << "HEX " << high << low << " -> DEC " << (int)value << std::endl;
+        std::cout << "HEX " << high << low << " -> DEC " << (int)value << std::endl;
 #endif
         // write the value to the output stream
         os << value;
@@ -265,7 +268,7 @@ WKBReader::readGeometry()
     unsigned char byteOrder = dis.readByte();
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB byteOrder: " << (int)byteOrder << std::endl;
+    std::cout << "WKB byteOrder: " << (int)byteOrder << std::endl;
 #endif
 
     // default is machine endian
@@ -288,7 +291,7 @@ WKBReader::readGeometry()
     int sfsqlHasM = (typeInt & 0x40000000) != 0;
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB geometryType: " << geometryType << std::endl;
+    std::cout << "WKB geometryType: " << geometryType << std::endl;
 #endif
 
     hasZ = sfsqlHasZ || isoHasZ;
@@ -304,17 +307,17 @@ WKBReader::readGeometry()
     }
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB hasZ: " << hasZ << std::endl;
+    std::cout << "WKB hasZ: " << hasZ << std::endl;
 #endif
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB dimensions: " << inputDimension << std::endl;
+    std::cout << "WKB dimensions: " << inputDimension << std::endl;
 #endif
 
     bool hasSRID = ((typeInt & 0x20000000) != 0);
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB hasSRID: " << hasSRID << std::endl;
+    std::cout << "WKB hasSRID: " << hasSRID << std::endl;
 #endif
 
     int SRID = 0;
@@ -391,7 +394,7 @@ WKBReader::readLineString()
     uint32_t size = dis.readUnsigned();
     minMemSize(GEOS_LINESTRING, size);
 #if DEBUG_WKB_READER
-    std::size_t << "WKB npoints: " << size << std::endl;
+    std::cout << "WKB npoints: " << size << std::endl;
 #endif
     auto pts = readCoordinateSequence(size);
     return factory.createLineString(std::move(pts));
@@ -403,7 +406,7 @@ WKBReader::readLinearRing()
     uint32_t size = dis.readUnsigned();
     minMemSize(GEOS_LINEARRING, size);
 #if DEBUG_WKB_READER
-    std::size_t << "WKB npoints: " << size << std::endl;
+    std::cout << "WKB npoints: " << size << std::endl;
 #endif
     auto pts = readCoordinateSequence(size);
     // Replace unclosed ring with closed
@@ -444,7 +447,7 @@ WKBReader::readPolygon()
     minMemSize(GEOS_POLYGON, numRings);
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB numRings: " << numRings << std::endl;
+    std::cout << "WKB numRings: " << numRings << std::endl;
 #endif
 
     std::unique_ptr<LinearRing> shell;
@@ -474,7 +477,7 @@ WKBReader::readCurvePolygon()
     minMemSize(GEOS_POLYGON, numRings);
 
 #if DEBUG_WKB_READER
-    std::size_t << "WKB numRings: " << numRings << std::endl;
+    std::cout << "WKB numRings: " << numRings << std::endl;
 #endif
 
     if (numRings == 0) {
@@ -617,7 +620,7 @@ WKBReader::readCoordinate()
         }
     }
 #if DEBUG_WKB_READER
-    std::size_t << "WKB coordinate: " << ordValues[0] << "," << ordValues[1] << std::endl;
+    std::cout << "WKB coordinate: " << ordValues[0] << "," << ordValues[1] << std::endl;
 #endif
 }
 
diff --git a/src/io/WKBWriter.cpp b/src/io/WKBWriter.cpp
index f7c83d38d..95c64b044 100644
--- a/src/io/WKBWriter.cpp
+++ b/src/io/WKBWriter.cpp
@@ -42,6 +42,10 @@
 
 #undef DEBUG_WKB_WRITER
 
+#if DEBUG_WKB_READER
+#include <iostream>
+#endif
+
 
 using namespace geos::geom;
 
@@ -380,7 +384,7 @@ void
 WKBWriter::writeCoordinate(const CoordinateSequence& cs, std::size_t idx)
 {
 #if DEBUG_WKB_WRITER
-    std::size_t << "writeCoordinate: X:" << cs.getX(idx) << " Y:" << cs.getY(idx) << std::endl;
+    std::cout << "writeCoordinate: X:" << cs.getX(idx) << " Y:" << cs.getY(idx) << std::endl;
 #endif
     assert(outStream);
 
@@ -442,4 +446,3 @@ WKBWriter::getWkbType(const Geometry& g) {
 
 } // namespace geos.io
 } // namespace geos
-
diff --git a/src/operation/overlay/snap/GeometrySnapper.cpp b/src/operation/overlay/snap/GeometrySnapper.cpp
index a2aed6eaa..294c2f93d 100644
--- a/src/operation/overlay/snap/GeometrySnapper.cpp
+++ b/src/operation/overlay/snap/GeometrySnapper.cpp
@@ -203,8 +203,8 @@ GeometrySnapper::snap(const geom::Geometry& g0,
     GeometrySnapper snapper1(g1);
     snapGeom.second = snapper1.snapTo(*snapGeom.first, snapTolerance);
 
-//	std::size_t << *snapGeom.first << std::endl;
-//	std::size_t << *snapGeom.second << std::endl;
+//	std::cout << *snapGeom.first << std::endl;
+//	std::cout << *snapGeom.second << std::endl;
 
 }
 
@@ -222,4 +222,3 @@ GeometrySnapper::snapToSelf(const geom::Geometry& g,
 } // namespace geos.operation.overlay
 } // namespace geos.operation
 } // namespace geos
-

-----------------------------------------------------------------------

Summary of changes:
 src/index/kdtree/KdTree.cpp                    |  9 ++++++++-
 src/io/WKBReader.cpp                           | 25 ++++++++++++++-----------
 src/io/WKBWriter.cpp                           |  7 +++++--
 src/operation/overlay/snap/GeometrySnapper.cpp |  5 ++---
 tests/unit/index/kdtree/KdTreeTest.cpp         | 18 ++++++++++++++++++
 5 files changed, 47 insertions(+), 17 deletions(-)


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From git at osgeo.org  Sat Jun 20 05:08:47 2026
From: git at osgeo.org (git at osgeo.org)
Date: Sat, 20 Jun 2026 05:08:47 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch 3.12 updated.
 ef1e94327bfb9f9f1b175d8a85f8220f72497f41
Message-ID: <20260620120848.028901C2BB1@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, 3.12 has been updated
       via  ef1e94327bfb9f9f1b175d8a85f8220f72497f41 (commit)
       via  34fd1f89d476e8ffcba1d01afa86de7b1685868c (commit)
      from  a8df87a0ff1989e8b3b088e25785ee7a0e4769a6 (commit)

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- Log -----------------------------------------------------------------
commit ef1e94327bfb9f9f1b175d8a85f8220f72497f41
Author: Daniel Baston <dbaston at gmail.com>
Date:   Thu Jun 18 12:49:34 2026 -0400

    KdTree: Disable optimizations in latest MSVC version
    
    References #1449

diff --git a/src/index/kdtree/KdTree.cpp b/src/index/kdtree/KdTree.cpp
index a0c2dfbff..9142a0789 100644
--- a/src/index/kdtree/KdTree.cpp
+++ b/src/index/kdtree/KdTree.cpp
@@ -226,6 +226,11 @@ KdTree::queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd,
     }
 }
 
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+// Avoid segfault with MSVC 19.51.36246.0
+// See https://github.com/libgeos/geos/issues/1449
+#pragma optimize("", off)
+#endif
 /*private*/
 KdNode*
 KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, bool odd)
@@ -257,7 +262,9 @@ KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, boo
     }
     return nullptr;
 }
-
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+#pragma optimize("", on)
+#endif
 
 /*public*/
 void

commit 34fd1f89d476e8ffcba1d01afa86de7b1685868c
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri Jun 19 09:24:45 2026 -0400

    KdTree: Add minimal test for #1449

diff --git a/tests/unit/index/kdtree/KdTreeTest.cpp b/tests/unit/index/kdtree/KdTreeTest.cpp
index 2de94f162..1121ca25b 100644
--- a/tests/unit/index/kdtree/KdTreeTest.cpp
+++ b/tests/unit/index/kdtree/KdTreeTest.cpp
@@ -189,6 +189,24 @@ void object::test<8> ()
     ensure(node->isRepeated());
 }
 
+template<>
+template<>
+void object::test<9>()
+{
+    set_test_name("query by point");
+    // minimal test for https://github.com/libgeos/geos/issues/1449
+
+    KdTree index;
+    ensure(index.query({ 6, 8 }) == nullptr);
+
+    const KdNode* node68 = index.insert({ 6, 8 });
+    ensure(node68);
+    ensure_equals(index.query({ 6, 8 }), node68);
+
+    const KdNode* node28 = index.insert({ 2, 8 });
+    ensure(node28);
+    ensure_equals(index.query({ 2, 8 }), node28);
+}
 
 
 

-----------------------------------------------------------------------

Summary of changes:
 src/index/kdtree/KdTree.cpp            |  9 ++++++++-
 tests/unit/index/kdtree/KdTreeTest.cpp | 18 ++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)


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From git at osgeo.org  Sat Jun 20 05:08:50 2026
From: git at osgeo.org (git at osgeo.org)
Date: Sat, 20 Jun 2026 05:08:50 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch 3.13 updated.
 4a31a2b4d3d17e01c028fe0539f2d0235bbd27f7
Message-ID: <20260620120850.E0FA21C3B83@trac.osgeo.org>

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the project "GEOS".

The branch, 3.13 has been updated
       via  4a31a2b4d3d17e01c028fe0539f2d0235bbd27f7 (commit)
       via  f84cfb521a2f72bf119d444701738eaac7bee1ea (commit)
      from  98da0fad0b9abff91349cf71d19196c5d48e258a (commit)

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- Log -----------------------------------------------------------------
commit 4a31a2b4d3d17e01c028fe0539f2d0235bbd27f7
Author: Daniel Baston <dbaston at gmail.com>
Date:   Thu Jun 18 12:49:34 2026 -0400

    KdTree: Disable optimizations in latest MSVC version
    
    References #1449

diff --git a/src/index/kdtree/KdTree.cpp b/src/index/kdtree/KdTree.cpp
index a0c2dfbff..9142a0789 100644
--- a/src/index/kdtree/KdTree.cpp
+++ b/src/index/kdtree/KdTree.cpp
@@ -226,6 +226,11 @@ KdTree::queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd,
     }
 }
 
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+// Avoid segfault with MSVC 19.51.36246.0
+// See https://github.com/libgeos/geos/issues/1449
+#pragma optimize("", off)
+#endif
 /*private*/
 KdNode*
 KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, bool odd)
@@ -257,7 +262,9 @@ KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, boo
     }
     return nullptr;
 }
-
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+#pragma optimize("", on)
+#endif
 
 /*public*/
 void

commit f84cfb521a2f72bf119d444701738eaac7bee1ea
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri Jun 19 09:24:45 2026 -0400

    KdTree: Add minimal test for #1449

diff --git a/tests/unit/index/kdtree/KdTreeTest.cpp b/tests/unit/index/kdtree/KdTreeTest.cpp
index 2de94f162..1121ca25b 100644
--- a/tests/unit/index/kdtree/KdTreeTest.cpp
+++ b/tests/unit/index/kdtree/KdTreeTest.cpp
@@ -189,6 +189,24 @@ void object::test<8> ()
     ensure(node->isRepeated());
 }
 
+template<>
+template<>
+void object::test<9>()
+{
+    set_test_name("query by point");
+    // minimal test for https://github.com/libgeos/geos/issues/1449
+
+    KdTree index;
+    ensure(index.query({ 6, 8 }) == nullptr);
+
+    const KdNode* node68 = index.insert({ 6, 8 });
+    ensure(node68);
+    ensure_equals(index.query({ 6, 8 }), node68);
+
+    const KdNode* node28 = index.insert({ 2, 8 });
+    ensure(node28);
+    ensure_equals(index.query({ 2, 8 }), node28);
+}
 
 
 

-----------------------------------------------------------------------

Summary of changes:
 src/index/kdtree/KdTree.cpp            |  9 ++++++++-
 tests/unit/index/kdtree/KdTreeTest.cpp | 18 ++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)


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From git at osgeo.org  Sat Jun 20 05:09:10 2026
From: git at osgeo.org (git at osgeo.org)
Date: Sat, 20 Jun 2026 05:09:10 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch 3.11 updated.
 72b0c32d012bbb078e6ba83b49b2676c340949a0
Message-ID: <20260620120910.757241C3C12@trac.osgeo.org>

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The branch, 3.11 has been updated
       via  72b0c32d012bbb078e6ba83b49b2676c340949a0 (commit)
       via  3ea733fad5ee52d828d5e83feae667eb7788576c (commit)
      from  0576a1fd2a49ef2c7b1abc7245e769565b169b02 (commit)

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- Log -----------------------------------------------------------------
commit 72b0c32d012bbb078e6ba83b49b2676c340949a0
Author: Daniel Baston <dbaston at gmail.com>
Date:   Thu Jun 18 12:49:34 2026 -0400

    KdTree: Disable optimizations in latest MSVC version
    
    References #1449

diff --git a/src/index/kdtree/KdTree.cpp b/src/index/kdtree/KdTree.cpp
index a0c2dfbff..9142a0789 100644
--- a/src/index/kdtree/KdTree.cpp
+++ b/src/index/kdtree/KdTree.cpp
@@ -226,6 +226,11 @@ KdTree::queryNode(KdNode* currentNode, const geom::Envelope& queryEnv, bool odd,
     }
 }
 
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+// Avoid segfault with MSVC 19.51.36246.0
+// See https://github.com/libgeos/geos/issues/1449
+#pragma optimize("", off)
+#endif
 /*private*/
 KdNode*
 KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, bool odd)
@@ -257,7 +262,9 @@ KdTree::queryNodePoint(KdNode* currentNode, const geom::Coordinate& queryPt, boo
     }
     return nullptr;
 }
-
+#if defined(_MSC_VER) && _MSC_FULL_VER > 195035734
+#pragma optimize("", on)
+#endif
 
 /*public*/
 void

commit 3ea733fad5ee52d828d5e83feae667eb7788576c
Author: Daniel Baston <dbaston at gmail.com>
Date:   Fri Jun 19 09:24:45 2026 -0400

    KdTree: Add minimal test for #1449

diff --git a/tests/unit/index/kdtree/KdTreeTest.cpp b/tests/unit/index/kdtree/KdTreeTest.cpp
index 2de94f162..1121ca25b 100644
--- a/tests/unit/index/kdtree/KdTreeTest.cpp
+++ b/tests/unit/index/kdtree/KdTreeTest.cpp
@@ -189,6 +189,24 @@ void object::test<8> ()
     ensure(node->isRepeated());
 }
 
+template<>
+template<>
+void object::test<9>()
+{
+    set_test_name("query by point");
+    // minimal test for https://github.com/libgeos/geos/issues/1449
+
+    KdTree index;
+    ensure(index.query({ 6, 8 }) == nullptr);
+
+    const KdNode* node68 = index.insert({ 6, 8 });
+    ensure(node68);
+    ensure_equals(index.query({ 6, 8 }), node68);
+
+    const KdNode* node28 = index.insert({ 2, 8 });
+    ensure(node28);
+    ensure_equals(index.query({ 2, 8 }), node28);
+}
 
 
 

-----------------------------------------------------------------------

Summary of changes:
 src/index/kdtree/KdTree.cpp            |  9 ++++++++-
 tests/unit/index/kdtree/KdTreeTest.cpp | 18 ++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Sat Jun 20 05:10:41 2026
From: git at osgeo.org (git at osgeo.org)
Date: Sat, 20 Jun 2026 05:10:41 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch 3.14 updated.
 7db6f62d50221a7ccac91c329a9a4fe61d172a56
Message-ID: <20260620121041.C86E41C2C62@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
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The branch, 3.14 has been updated
       via  7db6f62d50221a7ccac91c329a9a4fe61d172a56 (commit)
      from  70f292941d2e2243f2db66cf1292bfcffcc001fb (commit)

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- Log -----------------------------------------------------------------
commit 7db6f62d50221a7ccac91c329a9a4fe61d172a56
Author: Daniel Baston <dbaston at gmail.com>
Date:   Sat Jun 20 08:10:23 2026 -0400

    CommonBits: clean UBSAN error (#1451)

diff --git a/src/precision/CommonBits.cpp b/src/precision/CommonBits.cpp
index e5d004ebb..179e0d557 100644
--- a/src/precision/CommonBits.cpp
+++ b/src/precision/CommonBits.cpp
@@ -14,6 +14,7 @@
  **********************************************************************/
 
 #include <geos/precision/CommonBits.h>
+#include <limits>
 
 namespace geos {
 namespace precision { // geos.precision
@@ -71,6 +72,11 @@ CommonBits::CommonBits()
 void
 CommonBits::add(double num)
 {
+    if (num > static_cast<double>(std::numeric_limits<std::int64_t>::max())) {
+        commonBits = 0;
+        return;
+    }
+
     int64_t numBits = (int64_t) num;
     if(isFirst) {
         commonBits = numBits;

-----------------------------------------------------------------------

Summary of changes:
 src/precision/CommonBits.cpp | 6 ++++++
 1 file changed, 6 insertions(+)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Mon Jun 22 17:52:00 2026
From: git at osgeo.org (git at osgeo.org)
Date: Mon, 22 Jun 2026 17:52:00 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 ab8e9c9a6059b407644e041dd739459631856514
Message-ID: <20260623005201.416CB1A2F44@trac.osgeo.org>

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The branch, main has been updated
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      from  b7e11f5710ace681562228b791651bbc28835986 (commit)

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- Log -----------------------------------------------------------------
commit ab8e9c9a6059b407644e041dd739459631856514
Author: Arthur Chan <arthur.chan at adalogics.com>
Date:   Tue Jun 23 01:51:39 2026 +0100

    OSS-Fuzz: Move fuzzers upstream (#1447)
    
    Signed-off-by: Arthur Chan <arthur.chan at adalogics.com>

diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 3401775c8..70af383b4 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -10,3 +10,4 @@
 ################################################################################
 add_subdirectory(unit)
 add_subdirectory(xmltester)
+add_subdirectory(fuzz)
diff --git a/tests/CMakeLists.txt b/tests/fuzz/CMakeLists.txt
similarity index 50%
copy from tests/CMakeLists.txt
copy to tests/fuzz/CMakeLists.txt
index 3401775c8..d8868ed88 100644
--- a/tests/CMakeLists.txt
+++ b/tests/fuzz/CMakeLists.txt
@@ -8,5 +8,12 @@
 # by the Free Software Foundation.
 # See the COPYING file for more information.
 ################################################################################
-add_subdirectory(unit)
-add_subdirectory(xmltester)
+if(DEFINED ENV{LIB_FUZZING_ENGINE})
+  add_executable(fuzz_geo2 fuzz_geo2.c)
+  target_include_directories(fuzz_geo2 PUBLIC $<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/include>)
+  target_link_libraries(fuzz_geo2 geos_c $ENV{LIB_FUZZING_ENGINE})
+
+  add_executable(fuzz_geojson fuzz_geojson.c)
+  target_include_directories(fuzz_geojson PUBLIC $<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/include>)
+  target_link_libraries(fuzz_geojson geos_c $ENV{LIB_FUZZING_ENGINE})
+endif()
diff --git a/tests/fuzz/fuzz_geo2.c b/tests/fuzz/fuzz_geo2.c
new file mode 100644
index 000000000..ceee7ea6b
--- /dev/null
+++ b/tests/fuzz/fuzz_geo2.c
@@ -0,0 +1,69 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdarg.h>
+#include <string.h>
+
+#include "geos_c.h"
+
+static int initialized = 0;
+FILE * flogOut;
+
+void
+notice(const char *fmt, ...) {
+    va_list ap;
+    fprintf( flogOut, "NOTICE: ");
+    va_start (ap, fmt);
+    vfprintf( flogOut, fmt, ap);
+    va_end(ap);
+    fprintf( flogOut, "\n" );
+}
+
+void
+log_and_exit(const char *fmt, ...) {
+    va_list ap;
+    fprintf( flogOut, "ERROR: ");
+    va_start (ap, fmt);
+    vfprintf( flogOut, fmt, ap);
+    va_end(ap);
+    fprintf( flogOut, "\n" );
+}
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+    if (initialized == 0) {
+        flogOut = fopen("/dev/null", "wb");
+        initGEOS(notice, log_and_exit);
+        initialized = 1;
+    }
+    size_t sep;
+    for (sep = 0; sep < Size; sep ++) {
+        if (Data[sep] == 0) {
+            break;
+        }
+    }
+    if (sep == Size) {
+        return 0;
+    }
+    GEOSGeometry *g1 = GEOSGeomFromWKT(Data);
+
+    if (g1 != NULL) {
+        GEOSGeometry *g2 = GEOSGeomFromWKB_buf(Data+sep, Size-sep);
+        if (g2 != NULL) {
+            size_t usize;
+            GEOSGeometry *g3 = GEOSIntersection(g1, g2);
+            GEOSGeom_destroy(g3);
+            g3 = GEOSDifference(g1, g2);
+            GEOSGeom_destroy(g3);
+            g3 = GEOSUnion(g1, g2);
+            GEOSGeom_destroy(g3);
+            unsigned char* uptr = GEOSGeomToWKB_buf(g1, &usize);
+            free(uptr);
+            GEOSGeom_destroy(g2);
+        }
+        char * r = GEOSGeomToWKT(g1);
+        free(r);
+        GEOSGeom_destroy(g1);
+    }
+    return 0;
+}
+
diff --git a/tests/fuzz/fuzz_geojson.c b/tests/fuzz/fuzz_geojson.c
new file mode 100644
index 000000000..bbdcc6bfd
--- /dev/null
+++ b/tests/fuzz/fuzz_geojson.c
@@ -0,0 +1,57 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdarg.h>
+#include <string.h>
+
+#include "geos_c.h"
+
+static int initialized = 0;
+FILE * flogOut;
+
+void
+notice(const char *fmt, ...) {
+    va_list ap;
+    fprintf( flogOut, "NOTICE: ");
+    va_start (ap, fmt);
+    vfprintf( flogOut, fmt, ap);
+    va_end(ap);
+    fprintf( flogOut, "\n" );
+}
+
+void
+log_and_exit(const char *fmt, ...) {
+    va_list ap;
+    fprintf( flogOut, "ERROR: ");
+    va_start (ap, fmt);
+    vfprintf( flogOut, fmt, ap);
+    va_end(ap);
+    fprintf( flogOut, "\n" );
+}
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+    if (initialized == 0) {
+        flogOut = fopen("/dev/null", "wb");
+        initGEOS(notice, log_and_exit);
+        initialized = 1;
+    }
+
+    char *json = (char *) malloc(Size + 1);
+    if (json == NULL) {
+        return 0;
+    }
+    memcpy(json, Data, Size);
+    json[Size] = '\0';
+
+    GEOSGeoJSONReader *reader = GEOSGeoJSONReader_create();
+    if (reader != NULL) {
+        GEOSGeometry *g = GEOSGeoJSONReader_readGeometry(reader, json);
+        if (g != NULL) {
+            GEOSGeom_destroy(g);
+        }
+        GEOSGeoJSONReader_destroy(reader);
+    }
+
+    free(json);
+    return 0;
+}
diff --git a/tests/fuzz/geojson.dict b/tests/fuzz/geojson.dict
new file mode 100644
index 000000000..14d2ee89b
--- /dev/null
+++ b/tests/fuzz/geojson.dict
@@ -0,0 +1,38 @@
+# GeoJSON tokens for fuzz_geojson (see geos::io::GeoJSONReader)
+# Object keys
+"type"
+"coordinates"
+"geometry"
+"geometries"
+"features"
+"properties"
+# Geometry / object type values
+"Point"
+"LineString"
+"Polygon"
+"MultiPoint"
+"MultiLineString"
+"MultiPolygon"
+"GeometryCollection"
+"Feature"
+"FeatureCollection"
+# Common key/value fragments
+"\"type\":"
+"\"coordinates\":"
+"\"geometry\":"
+"\"properties\":"
+"\"features\":"
+"\"geometries\":"
+# Structural / literal tokens
+"{"
+"}"
+"["
+"]"
+":"
+","
+"true"
+"false"
+"null"
+"0.0"
+"1.0"
+"1e10"
diff --git a/tests/fuzz/geojson_seed_corpus/feature.json b/tests/fuzz/geojson_seed_corpus/feature.json
new file mode 100644
index 000000000..0ead4f4eb
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/feature.json
@@ -0,0 +1 @@
+{"type":"Feature","geometry":{"type":"Point","coordinates":[100.0,0.0]},"properties":{"name":"x","n":1,"b":true,"nil":null}}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/featurecollection.json b/tests/fuzz/geojson_seed_corpus/featurecollection.json
new file mode 100644
index 000000000..9913dd38f
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/featurecollection.json
@@ -0,0 +1 @@
+{"type":"FeatureCollection","features":[{"type":"Feature","geometry":{"type":"Point","coordinates":[100.0,0.0]},"properties":{}},{"type":"Feature","geometry":{"type":"Polygon","coordinates":[[[100.0,0.0],[101.0,0.0],[101.0,1.0],[100.0,0.0]]]},"properties":{"k":"v"}}]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/geometrycollection.json b/tests/fuzz/geojson_seed_corpus/geometrycollection.json
new file mode 100644
index 000000000..0c78938cd
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/geometrycollection.json
@@ -0,0 +1 @@
+{"type":"GeometryCollection","geometries":[{"type":"Point","coordinates":[100.0,0.0]},{"type":"LineString","coordinates":[[101.0,0.0],[102.0,1.0]]}]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/linestring.json b/tests/fuzz/geojson_seed_corpus/linestring.json
new file mode 100644
index 000000000..4a40c6726
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/linestring.json
@@ -0,0 +1 @@
+{"type":"LineString","coordinates":[[100.0,0.0],[101.0,1.0]]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/multilinestring.json b/tests/fuzz/geojson_seed_corpus/multilinestring.json
new file mode 100644
index 000000000..68aa13f58
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/multilinestring.json
@@ -0,0 +1 @@
+{"type":"MultiLineString","coordinates":[[[100.0,0.0],[101.0,1.0]],[[102.0,2.0],[103.0,3.0]]]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/multipoint.json b/tests/fuzz/geojson_seed_corpus/multipoint.json
new file mode 100644
index 000000000..27c3d27de
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/multipoint.json
@@ -0,0 +1 @@
+{"type":"MultiPoint","coordinates":[[100.0,0.0],[101.0,1.0]]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/multipolygon.json b/tests/fuzz/geojson_seed_corpus/multipolygon.json
new file mode 100644
index 000000000..afa67db9f
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/multipolygon.json
@@ -0,0 +1 @@
+{"type":"MultiPolygon","coordinates":[[[[102.0,2.0],[103.0,2.0],[103.0,3.0],[102.0,3.0],[102.0,2.0]]],[[[100.0,0.0],[101.0,0.0],[101.0,1.0],[100.0,1.0],[100.0,0.0]]]]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/point.json b/tests/fuzz/geojson_seed_corpus/point.json
new file mode 100644
index 000000000..2756bae67
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/point.json
@@ -0,0 +1 @@
+{"type":"Point","coordinates":[100.0,0.0]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/point_z.json b/tests/fuzz/geojson_seed_corpus/point_z.json
new file mode 100644
index 000000000..a13a91b66
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/point_z.json
@@ -0,0 +1 @@
+{"type":"Point","coordinates":[100.0,0.0,50.0]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/polygon.json b/tests/fuzz/geojson_seed_corpus/polygon.json
new file mode 100644
index 000000000..9c573c1a3
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/polygon.json
@@ -0,0 +1 @@
+{"type":"Polygon","coordinates":[[[100.0,0.0],[101.0,0.0],[101.0,1.0],[100.0,1.0],[100.0,0.0]]]}
\ No newline at end of file
diff --git a/tests/fuzz/geojson_seed_corpus/polygon_hole.json b/tests/fuzz/geojson_seed_corpus/polygon_hole.json
new file mode 100644
index 000000000..11661ebf6
--- /dev/null
+++ b/tests/fuzz/geojson_seed_corpus/polygon_hole.json
@@ -0,0 +1 @@
+{"type":"Polygon","coordinates":[[[100.0,0.0],[101.0,0.0],[101.0,1.0],[100.0,1.0],[100.0,0.0]],[[100.2,0.2],[100.8,0.2],[100.8,0.8],[100.2,0.8],[100.2,0.2]]]}
\ No newline at end of file

-----------------------------------------------------------------------

Summary of changes:
 tests/CMakeLists.txt                               |  1 +
 {benchmarks/index => tests/fuzz}/CMakeLists.txt    | 16 +++--
 tests/fuzz/fuzz_geo2.c                             | 69 ++++++++++++++++++++++
 tests/fuzz/fuzz_geojson.c                          | 57 ++++++++++++++++++
 tests/fuzz/geojson.dict                            | 38 ++++++++++++
 tests/fuzz/geojson_seed_corpus/feature.json        |  1 +
 .../geojson_seed_corpus/featurecollection.json     |  1 +
 .../geojson_seed_corpus/geometrycollection.json    |  1 +
 tests/fuzz/geojson_seed_corpus/linestring.json     |  1 +
 .../fuzz/geojson_seed_corpus/multilinestring.json  |  1 +
 tests/fuzz/geojson_seed_corpus/multipoint.json     |  1 +
 tests/fuzz/geojson_seed_corpus/multipolygon.json   |  1 +
 tests/fuzz/geojson_seed_corpus/point.json          |  1 +
 tests/fuzz/geojson_seed_corpus/point_z.json        |  1 +
 tests/fuzz/geojson_seed_corpus/polygon.json        |  1 +
 tests/fuzz/geojson_seed_corpus/polygon_hole.json   |  1 +
 16 files changed, 183 insertions(+), 9 deletions(-)
 copy {benchmarks/index => tests/fuzz}/CMakeLists.txt (51%)
 create mode 100644 tests/fuzz/fuzz_geo2.c
 create mode 100644 tests/fuzz/fuzz_geojson.c
 create mode 100644 tests/fuzz/geojson.dict
 create mode 100644 tests/fuzz/geojson_seed_corpus/feature.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/featurecollection.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/geometrycollection.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/linestring.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/multilinestring.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/multipoint.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/multipolygon.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/point.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/point_z.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/polygon.json
 create mode 100644 tests/fuzz/geojson_seed_corpus/polygon_hole.json


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Tue Jun 23 14:14:53 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue, 23 Jun 2026 14:14:53 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 cbd9839e30e64d2f851358feaec2ccb2acc1b804
Message-ID: <20260623211453.DD3D41B4889@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, main has been updated
       via  cbd9839e30e64d2f851358feaec2ccb2acc1b804 (commit)
      from  ab8e9c9a6059b407644e041dd739459631856514 (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
commit cbd9839e30e64d2f851358feaec2ccb2acc1b804
Author: Paul Ramsey <pramsey at cleverelephant.ca>
Date:   Tue Jun 23 21:12:01 2026 +0000

    Fuzzer fixes
    
    Ensure WKB pointer actually points to start of
    WKB segment and not the separator null byte.
    Only setup JSON reader once, not for every
    iteration.

diff --git a/tests/fuzz/fuzz_geo2.c b/tests/fuzz/fuzz_geo2.c
index ceee7ea6b..26c22e79c 100644
--- a/tests/fuzz/fuzz_geo2.c
+++ b/tests/fuzz/fuzz_geo2.c
@@ -47,7 +47,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
     GEOSGeometry *g1 = GEOSGeomFromWKT(Data);
 
     if (g1 != NULL) {
-        GEOSGeometry *g2 = GEOSGeomFromWKB_buf(Data+sep, Size-sep);
+        GEOSGeometry *g2 = GEOSGeomFromWKB_buf(Data+sep+1, Size-sep-1);
         if (g2 != NULL) {
             size_t usize;
             GEOSGeometry *g3 = GEOSIntersection(g1, g2);
@@ -57,11 +57,11 @@ int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
             g3 = GEOSUnion(g1, g2);
             GEOSGeom_destroy(g3);
             unsigned char* uptr = GEOSGeomToWKB_buf(g1, &usize);
-            free(uptr);
+            GEOSFree(uptr);
             GEOSGeom_destroy(g2);
         }
         char * r = GEOSGeomToWKT(g1);
-        free(r);
+        GEOSFree(r);
         GEOSGeom_destroy(g1);
     }
     return 0;
diff --git a/tests/fuzz/fuzz_geojson.c b/tests/fuzz/fuzz_geojson.c
index bbdcc6bfd..28d100ce0 100644
--- a/tests/fuzz/fuzz_geojson.c
+++ b/tests/fuzz/fuzz_geojson.c
@@ -6,8 +6,8 @@
 
 #include "geos_c.h"
 
-static int initialized = 0;
-FILE * flogOut;
+static FILE * flogOut;
+static GEOSGeoJSONReader *reader;
 
 void
 notice(const char *fmt, ...) {
@@ -29,11 +29,17 @@ log_and_exit(const char *fmt, ...) {
     fprintf( flogOut, "\n" );
 }
 
+int LLVMFuzzerInitialize(int *argc, char ***argv) {
+    (void)argc; (void)argv;
+    flogOut = fopen("/dev/null", "wb");
+    initGEOS(notice, log_and_exit);
+    reader = GEOSGeoJSONReader_create();
+    return 0;
+}
+
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
-    if (initialized == 0) {
-        flogOut = fopen("/dev/null", "wb");
-        initGEOS(notice, log_and_exit);
-        initialized = 1;
+    if (reader == NULL) {
+        return 0;
     }
 
     char *json = (char *) malloc(Size + 1);
@@ -43,13 +49,9 @@ int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
     memcpy(json, Data, Size);
     json[Size] = '\0';
 
-    GEOSGeoJSONReader *reader = GEOSGeoJSONReader_create();
-    if (reader != NULL) {
-        GEOSGeometry *g = GEOSGeoJSONReader_readGeometry(reader, json);
-        if (g != NULL) {
-            GEOSGeom_destroy(g);
-        }
-        GEOSGeoJSONReader_destroy(reader);
+    GEOSGeometry *g = GEOSGeoJSONReader_readGeometry(reader, json);
+    if (g != NULL) {
+        GEOSGeom_destroy(g);
     }
 
     free(json);

-----------------------------------------------------------------------

Summary of changes:
 tests/fuzz/fuzz_geo2.c    |  6 +++---
 tests/fuzz/fuzz_geojson.c | 28 +++++++++++++++-------------
 2 files changed, 18 insertions(+), 16 deletions(-)


hooks/post-receive
-- 
GEOS

From git at osgeo.org  Tue Jun 23 14:42:18 2026
From: git at osgeo.org (git at osgeo.org)
Date: Tue, 23 Jun 2026 14:42:18 -0700 (PDT)
Subject: [geos-commits] [SCM] GEOS branch main updated.
 72a954f63aab8eaec71d6570d900b3450e0ea946
Message-ID: <20260623214218.71FA91B4D99@trac.osgeo.org>

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GEOS".

The branch, main has been updated
       via  72a954f63aab8eaec71d6570d900b3450e0ea946 (commit)
      from  cbd9839e30e64d2f851358feaec2ccb2acc1b804 (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
commit 72a954f63aab8eaec71d6570d900b3450e0ea946
Author: Paul Ramsey <pramsey at cleverelephant.ca>
Date:   Tue Jun 23 14:41:54 2026 -0700

    CMake status entry when ossfuzz is enabled

diff --git a/tests/fuzz/CMakeLists.txt b/tests/fuzz/CMakeLists.txt
index d8868ed88..e96ac876f 100644
--- a/tests/fuzz/CMakeLists.txt
+++ b/tests/fuzz/CMakeLists.txt
@@ -10,6 +10,7 @@
 ################################################################################
 if(DEFINED ENV{LIB_FUZZING_ENGINE})
   add_executable(fuzz_geo2 fuzz_geo2.c)
+  message(STATUS "GEOS: OSSFuzz build ENABLED")
   target_include_directories(fuzz_geo2 PUBLIC $<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/include>)
   target_link_libraries(fuzz_geo2 geos_c $ENV{LIB_FUZZING_ENGINE})
 

-----------------------------------------------------------------------

Summary of changes:
 tests/fuzz/CMakeLists.txt | 1 +
 1 file changed, 1 insertion(+)


hooks/post-receive
-- 
GEOS