geos::operation::overlay Namespace Reference

Contains classes that perform a topological overlay to compute boolean spatial functions. More...


Classes

class  EdgeSetNoder
 Nodes a set of edges. More...
class  FuzzyPointLocator
 Finds the most likely Location of a point relative to the polygonal components of a geometry, using a tolerance value. More...
class  LineBuilder
 Forms JTS LineStrings out of a the graph of geomgraph::DirectedEdge created by an OverlayOp. More...
class  MaximalEdgeRing
 A ring of edges which may contain nodes of degree > 2. More...
class  MinimalEdgeRing
 A ring of Edges with the property that no node has degree greater than 2. More...
class  OffsetPointGenerator
 Generates points offset from both sides of all segments in a geometry. More...
class  OverlayNodeFactory
 Creates nodes for use in the geomgraph::PlanarGraph constructed during overlay operations. NOTE: also used by operation::valid. More...
class  OverlayOp
 Computes the overlay of two Geometry. More...
struct  overlayOp
 OverlayOp::overlayOp Adapter for use with geom::BinaryOp. More...
class  OverlayResultValidator
 Validates that the result of an overlay operation is geometrically correct within a given tolerance. More...
class  PointBuilder
 Constructs geom::Point s from the nodes of an overlay graph. More...
class  PolygonBuilder
 Forms Polygon out of a graph of geomgraph::DirectedEdge. More...


Detailed Description

Contains classes that perform a topological overlay to compute boolean spatial functions.

The Overlay Algorithm is used in spatial analysis methods for computing set-theoretic operations (boolean combinations) of input Geometrys. The algorithm for computing the overlay uses the intersection operations supported by topology graphs. To compute an overlay it is necessary to explicitly compute the resultant graph formed by the computed intersections.

The algorithm to compute a set-theoretic spatial analysis method has the following steps:

Package Specification


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