geos::operation::polygonize::PolygonizeGraph Class Reference

Represents a planar graph of edges that can be used to compute a polygonization, and implements the algorithms to compute the EdgeRings formed by the graph. More...

#include <PolygonizeGraph.h>

Inheritance diagram for geos::operation::polygonize::PolygonizeGraph:

List of all members.

Public Member Functions
	PolygonizeGraph (const geom::GeometryFactory *newFactory)
	Create a new polygonization graph.
	~PolygonizeGraph ()
	Destroy a polygonization graph.
void	addEdge (const geom::LineString *line)
	Add a LineString forming an edge of the polygon graph.
std::vector< EdgeRing * > *	getEdgeRings ()
	Computes the EdgeRings formed by the edges in this graph.
std::vector< const geom::LineString * > *	deleteCutEdges ()
	Finds and removes all cut edges from the graph.
std::vector< const geom::LineString * > *	deleteDangles ()
	Marks all edges from the graph which are "dangles".
Static Public Member Functions
static void	deleteAllEdges (planargraph::Node *node)
	Deletes all edges at a node.

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Detailed Description

Represents a planar graph of edges that can be used to compute a polygonization, and implements the algorithms to compute the EdgeRings formed by the graph.

The marked flag on DirectedEdge is used to indicate that a directed edge has be logically deleted from the graph.

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Member Function Documentation

void geos::operation::polygonize::PolygonizeGraph::addEdge (  const geom::LineString *  line  )

Add a LineString forming an edge of the polygon graph. Parameters: line  the line to add

std::vector<const geom::LineString*>* geos::operation::polygonize::PolygonizeGraph::deleteCutEdges (   )

Finds and removes all cut edges from the graph. Returns: a list of the LineString forming the removed cut edges

std::vector<const geom::LineString*>* geos::operation::polygonize::PolygonizeGraph::deleteDangles (   )

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 Returns: a List containing the LineStrings that formed dangles

std::vector<EdgeRing*>* geos::operation::polygonize::PolygonizeGraph::getEdgeRings (   )

Computes the EdgeRings formed by the edges in this graph. Returns: a list of the EdgeRing found by the polygonization process.

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The documentation for this class was generated from the following file:

• PolygonizeGraph.h

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