[geos-commits] r2730 - in trunk/source: headers/geos/operation/polygonize operation/polygonize

[svn_geos at osgeo.org]

Author: strk
Date: 2009-11-19 15:29:01 -0500 (Thu, 19 Nov 2009)
New Revision: 2730

Modified:
   trunk/source/headers/geos/operation/polygonize/PolygonizeGraph.h
   trunk/source/operation/polygonize/PolygonizeGraph.cpp
   trunk/source/operation/polygonize/Polygonizer.cpp
Log:
Don't force heap allocation of std::vector in PolygonizeGraph when deleting dangles (moved allocation higher, in Polygonizer, so needs a second pass)


Modified: trunk/source/headers/geos/operation/polygonize/PolygonizeGraph.h
===================================================================
--- trunk/source/headers/geos/operation/polygonize/PolygonizeGraph.h	2009-11-19 20:20:29 UTC (rev 2729)
+++ trunk/source/headers/geos/operation/polygonize/PolygonizeGraph.h	2009-11-19 20:29:01 UTC (rev 2730)
@@ -122,9 +122,10 @@
 	 * In order to handle large recursion depths efficiently,
 	 * an explicit recursion stack is used
 	 *
-	 * @return a List containing the LineStrings that formed dangles
+	 * @param dangleLines : the LineStrings that formed dangles will
+	 *                      be push_back'ed here
 	 */
-	std::vector<const geom::LineString*>* deleteDangles();
+	void deleteDangles(std::vector<const geom::LineString*> &dangleLines);
 
 private:
 

Modified: trunk/source/operation/polygonize/PolygonizeGraph.cpp
===================================================================
--- trunk/source/operation/polygonize/PolygonizeGraph.cpp	2009-11-19 20:20:29 UTC (rev 2729)
+++ trunk/source/operation/polygonize/PolygonizeGraph.cpp	2009-11-19 20:29:01 UTC (rev 2730)
@@ -440,21 +440,11 @@
 	return er;
 }
 
-/**
- * Marks all edges from the graph which are "dangles".
- * Dangles are which are incident on a node with degree 1.
- * This process is recursive, since removing a dangling edge
- * may result in another edge becoming a dangle.
- * In order to handle large recursion depths efficiently,
- * an explicit recursion stack is used
- *
- * @return a List containing the LineStrings that formed dangles
- */
-std::vector<const LineString*>*
-PolygonizeGraph::deleteDangles()
+/* public */
+void
+PolygonizeGraph::deleteDangles(std::vector<const LineString*>& dangleLines)
 {
 	std::vector<Node*> *nodesToRemove=findNodesOfDegree(1);
-	std::vector<const LineString*> *dangleLines=new std::vector<const LineString*>();
 	std::vector<Node*> nodeStack;
 	for(int i=0;i<(int)nodesToRemove->size();i++) {
 		nodeStack.push_back((*nodesToRemove)[i]);
@@ -475,14 +465,13 @@
 				sym->setMarked(true);
 			// save the line as a dangle
 			PolygonizeEdge *e=(PolygonizeEdge*) de->getEdge();
-			dangleLines->push_back(e->getLine());
+			dangleLines.push_back(e->getLine());
 			Node *toNode=de->getToNode();
 			// add the toNode to the list to be processed, if it is now a dangle
 			if (getDegreeNonDeleted(toNode)==1)
 				nodeStack.push_back(toNode);
 		}
 	}
-	return dangleLines;
 }
 
 } // namespace geos.operation.polygonize

Modified: trunk/source/operation/polygonize/Polygonizer.cpp
===================================================================
--- trunk/source/operation/polygonize/Polygonizer.cpp	2009-11-19 20:20:29 UTC (rev 2729)
+++ trunk/source/operation/polygonize/Polygonizer.cpp	2009-11-19 20:29:01 UTC (rev 2730)
@@ -234,7 +234,9 @@
 	// if no geometries were supplied it's possible graph could be null
 	if (graph==NULL) return; 
 
-	dangles=graph->deleteDangles();
+	// TODO: drop this heap allocation
+	dangles = new std::vector<const LineString*>();
+	graph->deleteDangles(*dangles);
 
 	// TODO: drop this heap allocation
 	cutEdges = new std::vector<const LineString*>();