Beispiel #1
0
/*
 * Finds and removes all cut edges from the graph.
 * @return a list of the LineString forming the removed cut edges
 */
vector<const LineString*> *
PolygonizeGraph::deleteCutEdges()
{
	computeNextCWEdges();

	// label the current set of edgerings
	delete findLabeledEdgeRings(dirEdges);

	/*
	 * Cut Edges are edges where both dirEdges have the same label.
	 * Delete them, and record them
	 */
	vector<const LineString*> *cutLines=new vector<const LineString*>();
	for(int i=0;i<(int)dirEdges->size();i++) {
		PolygonizeDirectedEdge *de=(PolygonizeDirectedEdge*)(*dirEdges)[i];
		if (de->isMarked()) continue;
		PolygonizeDirectedEdge *sym=(PolygonizeDirectedEdge*) de->getSym();
		if (de->getLabel()==sym->getLabel()) {
			de->setMarked(true);
			sym->setMarked(true);
			// save the line as a cut edge
			PolygonizeEdge *e=(PolygonizeEdge*) de->getEdge();
			cutLines->push_back(e->getLine());
		}
	}
	return cutLines;
}
Beispiel #2
0
/**
 * Computes the EdgeRings formed by the edges in this graph.
 * @return a list of the EdgeRing found by the polygonization process.
 */
vector<polygonizeEdgeRing*>*
PolygonizeGraph::getEdgeRings()
{
	// maybe could optimize this, since most of these pointers should
	// be set correctly already
	// by deleteCutEdges()
	computeNextCWEdges();

	// clear labels of all edges in graph
	label(dirEdges,-1);
	vector<PolygonizeDirectedEdge*> *maximalRings=findLabeledEdgeRings(dirEdges);
	convertMaximalToMinimalEdgeRings(maximalRings);
	delete maximalRings;

	// find all edgerings
	vector<polygonizeEdgeRing*> *edgeRingList=new vector<polygonizeEdgeRing*>();
	for(int i=0;i<(int)dirEdges->size();i++) {
		PolygonizeDirectedEdge *de=(PolygonizeDirectedEdge*)(*dirEdges)[i];
		if (de->isMarked()) continue;
		if (de->isInRing()) continue;
		polygonizeEdgeRing *er=findEdgeRing(de);
		edgeRingList->push_back(er);
	}
	return edgeRingList;
}
Beispiel #3
0
/* public */
void
PolygonizeGraph::getEdgeRings(std::vector<EdgeRing*>& edgeRingList)
{
	// maybe could optimize this, since most of these pointers should
	// be set correctly already
	// by deleteCutEdges()
	computeNextCWEdges();

	// clear labels of all edges in graph
	label(dirEdges, -1);
	std::vector<PolygonizeDirectedEdge*> maximalRings;
	findLabeledEdgeRings(dirEdges, maximalRings);
	convertMaximalToMinimalEdgeRings(maximalRings);
	maximalRings.clear(); // not needed anymore

	// find all edgerings
	for(unsigned int i=0; i<dirEdges.size(); ++i)
	{
		PolygonizeDirectedEdge *de=(PolygonizeDirectedEdge*)dirEdges[i];
		if (de->isMarked()) continue;
		if (de->isInRing()) continue;
		EdgeRing *er=findEdgeRing(de);
		edgeRingList.push_back(er);
	}
}
Beispiel #4
0
/* public */
void
PolygonizeGraph::deleteCutEdges(std::vector<const LineString*> &cutLines)
{
	computeNextCWEdges();

	typedef std::vector<PolygonizeDirectedEdge*> DirEdges;

	// label the current set of edgerings
	DirEdges junk;
	findLabeledEdgeRings(dirEdges, junk);
	junk.clear(); // not needed anymore

	/*
	 * Cut Edges are edges where both dirEdges have the same label.
	 * Delete them, and record them
	 */
	for (DirEdges::size_type i=0, in=dirEdges.size(); i<in; ++i)
	{
		DirectedEdge *de_ = dirEdges[i];
#ifdef GEOS_CAST_PARANOIA
		assert(dynamic_cast<PolygonizeDirectedEdge*>(de_));
#endif
		PolygonizeDirectedEdge *de =
			static_cast<PolygonizeDirectedEdge*>(de_);

		if (de->isMarked()) continue;

		DirectedEdge *sym_ = de->getSym();
#ifdef GEOS_CAST_PARANOIA
		assert(dynamic_cast<PolygonizeDirectedEdge*>(sym_));
#endif
		PolygonizeDirectedEdge *sym =
			static_cast<PolygonizeDirectedEdge*>(sym_);

		if (de->getLabel()==sym->getLabel())
		{
			de->setMarked(true);
			sym->setMarked(true);

			// save the line as a cut edge
			Edge *e_ = de->getEdge();
#ifdef GEOS_CAST_PARANOIA
			assert(dynamic_cast<PolygonizeEdge*>(e_));
#endif
			PolygonizeEdge *e = static_cast<PolygonizeEdge*>(e_);

			cutLines.push_back(e->getLine());
		}
	}
}