[PostGIS] #2574: Have ST_3DDWithin to recognize Triangle as a type

[PostGIS]

#2574: Have ST_3DDWithin to recognize Triangle as a type
----------------------------+-----------------------------
  Reporter:  smathermather  |      Owner:  colivier
      Type:  enhancement    |     Status:  closed
  Priority:  medium         |  Milestone:  PostGIS Fund Me
 Component:  postgis        |    Version:  2.1.x
Resolution:  fixed          |   Keywords:
----------------------------+-----------------------------
Changes (by komzpa):

 * resolution:   => fixed
 * status:  new => closed

Comment:

 Works
 {{{
 POSTGIS="3.7.0dev 3.6.0rc2-157-g385a9ff4e" [EXTENSION] PGSQL="180"
 GEOS="3.14.0-CAPI-1.20.4" PROJ="9.7.0 NETWORK_ENABLED=OFF
 URL_ENDPOINT=https://cdn.proj.org USER_WRITABLE_DIRECTORY=/tmp/proj
 DATABASE_PATH=/usr/share/proj/proj.db" (compiled against PROJ 9.7.0)
 GDAL="GDAL 3.12.0beta1 "Chicoutimi", released 2025/10/20" LIBXML="2.15.1"
 LIBJSON="0.18" LIBPROTOBUF="1.5.1" WAGYU="0.5.0 (Internal)" RASTER


 16:50:48 [kom] >
 -- Helpers: two triangles and a few other geoms
 -- tri_a: near origin, XY plane at z=0
 WITH
 tri_a AS (
   SELECT 'TRIANGLE Z ((0 0 0, 1 0 0, 0 1 0, 0 0 0))'::geometry AS g
 ),
 -- tri_b_xy: translated along +X by 10, same plane z=0
 -- shortest 3D distance to tri_a is exactly 9 (from x=1 to x=10)
 tri_b_xy AS (
   SELECT 'TRIANGLE Z ((10 0 0, 11 0 0, 10 1 0, 10 0 0))'::geometry AS g
 ),
 -- tri_b_xyz: same footprint as tri_b_xy but raised to z=8
 -- true 3D shortest distance to tri_a is sqrt(9^2 + 8^2) = sqrt(145) ≈
 12.0415945788
 tri_b_xyz AS (
   SELECT 'TRIANGLE Z ((10 0 8, 11 0 8, 10 1 8, 10 0 8))'::geometry AS g
 ),
 pt_inside_tri_a AS (
   SELECT ST_MakePoint(0.25, 0.25, 0.0)::geometry AS g
 ),
 poly_near_tri_a AS (
   -- simple square polygon hovering 0.5 units above tri_a in Z
   SELECT 'POLYGON Z ((0.2 0.2 0.5, 0.8 0.2 0.5, 0.8 0.8 0.5, 0.2 0.8 0.5,
 0.2 0.2 0.5))'::geometry AS g
 )

 -- 1) REPRO of current pre-fix failure (expected to ERROR today; should
 PASS after fix):
 --    If your build still errors with "Unsupported geometry type:
 Triangle",
 --    these SELECTs will fail right here. After the fix, they return
 booleans.
 SELECT
   'tri vs tri (XY, d=8) expect false' AS test,
   ST_3DDWithin((SELECT g FROM tri_a), (SELECT g FROM tri_b_xy), 8.0) AS ok
 UNION ALL
 SELECT
   'tri vs tri (XY, d=9) expect true',
   ST_3DDWithin((SELECT g FROM tri_a), (SELECT g FROM tri_b_xy), 9.0)
 UNION ALL
 SELECT
   'tri vs tri (XYZ, d=12) expect false',
   ST_3DDWithin((SELECT g FROM tri_a), (SELECT g FROM tri_b_xyz), 12.0)
 UNION ALL
 SELECT
   'tri vs tri (XYZ, d=12.05) expect true',
   ST_3DDWithin((SELECT g FROM tri_a), (SELECT g FROM tri_b_xyz), 12.05)
 UNION ALL
 SELECT
   'tri vs point (inside, d=0) expect true',
   ST_3DDWithin((SELECT g FROM tri_a), (SELECT g FROM pt_inside_tri_a),
 0.0)
 UNION ALL
 SELECT
   'tri vs polygon (hovering at z=0.5, d=0.5) expect true',
   ST_3DDWithin((SELECT g FROM tri_a), (SELECT g FROM poly_near_tri_a),
 0.5);
 ┌───────────────────────────────────────────────────────┬────┐
 │                         test                          │ ok │
 ├───────────────────────────────────────────────────────┼────┤
 │ tri vs tri (XY, d=8) expect false                     │ f  │
 │ tri vs tri (XY, d=9) expect true                      │ t  │
 │ tri vs tri (XYZ, d=12) expect false                   │ f  │
 │ tri vs tri (XYZ, d=12.05) expect true                 │ t  │
 │ tri vs point (inside, d=0) expect true                │ t  │
 │ tri vs polygon (hovering at z=0.5, d=0.5) expect true │ t  │
 └───────────────────────────────────────────────────────┴────┘
 (6 rows)

 Time: 0,629 ms
 }}}
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/2574#comment:6>
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