Class VoronoiDiagramBuilder

Hierarchy: Object , VoronoiDiagramBuilder

public class VoronoiDiagramBuilder

A utility class which creates Voronoi Diagrams from collections of points. The diagram is returned as a GeometryCollection of Polygons representing the faces of the Voronoi diagram. The faces are clipped to the larger of:

an envelope supplied by setClipEnvelope(Envelope)
an envelope determined by the input sites

The userData attribute of each face Polygon is set to the Coordinate of the corresponding input site. This allows using a Map to link faces to data associated with sites.

Authors:: Martin Davis

public VoronoiDiagramBuilder()

Creates a new Voronoi diagram builder.

public void setSites(Geometry geom)

Sets the sites (point or vertices) which will be diagrammed. All vertices of the given geometry will be used as sites.

Parameters:: geom - geom the geometry from which the sites will be extracted.

public void setSites(Collection coords)

Sets the sites (point or vertices) which will be diagrammed from a collection of Coordinates.

Parameters:: coords - coords a collection of Coordinates.

public void setClipEnvelope(Envelope clipEnv)

Sets the envelope to clip the diagram to. The diagram will be clipped to the larger of this envelope or an envelope surrounding the sites.

Parameters:: clipEnv - clipEnv the clip envelope.

public void setTolerance(double tolerance)

Sets the snapping tolerance which will be used to improved the robustness of the triangulation computation. A tolerance of 0.0 specifies that no snapping will take place.

Parameters:: tolerance - tolerance the tolerance distance to use

public QuadEdgeSubdivision getSubdivision()

Gets the QuadEdgeSubdivision which models the computed diagram.

Returns:: the subdivision containing the triangulation

public Geometry getDiagram(GeometryFactory geomFact)

Gets the faces of the computed diagram as a GeometryCollection of Polygons, clipped as specified.

The userData attribute of each face Polygon is set to the Coordinate of the corresponding input site. This allows using a Map to link faces to data associated with sites.

Parameters:: geomFact - geomFact the geometry factory to use to create the output

Returns:: a GeometryCollection containing the face Polygons of the diagram