[geos-commits] r3623 - trunk/src/geom

[svn_geos at osgeo.org]

Author: strk
Date: 2012-05-08 11:41:40 -0700 (Tue, 08 May 2012)
New Revision: 3623

Modified:
   trunk/src/geom/Geometry.cpp
Log:
Envelope-based short-circuit for Geometry->symDifference (#543)

Modified: trunk/src/geom/Geometry.cpp
===================================================================
--- trunk/src/geom/Geometry.cpp	2012-05-08 18:23:38 UTC (rev 3622)
+++ trunk/src/geom/Geometry.cpp	2012-05-08 18:41:40 UTC (rev 3623)
@@ -606,6 +606,39 @@
 	if ( isEmpty() ) return other->clone();
 	if ( other->isEmpty() ) return clone();
 
+	// if envelopes are disjoint return a MULTI geom or
+	// a geometrycollection
+	if ( ! getEnvelopeInternal()->intersects(other->getEnvelopeInternal()) )
+	{
+		const GeometryCollection *coll;
+
+		size_t ngeomsThis = getNumGeometries();
+		size_t ngeomsOther = other->getNumGeometries();
+
+		// Allocated for ownership transfer
+		vector<Geometry *> *v = new vector<Geometry *>();
+		v->reserve(ngeomsThis+ngeomsOther);
+
+
+		if ( NULL != (coll = dynamic_cast<const GeometryCollection *>(this)) )
+		{
+			for (size_t i=0; i<ngeomsThis; ++i)
+				v->push_back(coll->getGeometryN(i)->clone());
+		} else {
+			v->push_back(this->clone());
+		}
+
+		if ( NULL != (coll = dynamic_cast<const GeometryCollection *>(other)) )
+		{
+			for (size_t i=0; i<ngeomsOther; ++i)
+				v->push_back(coll->getGeometryN(i)->clone());
+		} else {
+			v->push_back(other->clone());
+		}
+
+		return factory->buildGeometry(v);
+	}
+
 	return BinaryOp(this, other, overlayOp(OverlayOp::opSYMDIFFERENCE)).release();
 }