Changeset 2730

Timestamp:

Nov 19, 2009, 12:29:01 PM (15 years ago)

Author:

strk

Message:

Don't force heap allocation of std::vector in PolygonizeGraph when deleting dangles (moved allocation higher, in Polygonizer, so needs a second pass)

Location:

trunk/source

Files:

• headers/geos/operation/polygonize/PolygonizeGraph.h (modified) (1 diff)
• operation/polygonize/PolygonizeGraph.cpp (modified) (3 diffs)
• operation/polygonize/Polygonizer.cpp (modified) (1 diff)

trunk/source/headers/geos/operation/polygonize/PolygonizeGraph.h

@@ -123 +123 @@
          * an explicit recursion stack is used
          *
-         * @return a List containing the LineStrings that formed dangles
-         */
-        std::vector<const geom::LineString*>* deleteDangles();
+         * @param dangleLines : the LineStrings that formed dangles will
+         *                      be push_back'ed here
+         */
+        void deleteDangles(std::vector<const geom::LineString*> &dangleLines);
 
 private:

trunk/source/operation/polygonize/PolygonizeGraph.cpp

@@ -441 +441 @@
 }
 
-/**
- * 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++) {
@@ -476 +466 @@
                         // 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
@@ -483 +473 @@
                 }
         }
-        return dangleLines;
 }
 

trunk/source/operation/polygonize/Polygonizer.cpp

@@ -235 +235 @@
         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