org.tinfour.voronoi

Class BoundedVoronoiDiagram

java.lang.Object

org.tinfour.voronoi.BoundedVoronoiDiagram

public class BoundedVoronoiDiagram
extends Object

Constructs a Voronoi Diagram structure from a set of sample points. The resulting structure is "bounded" in the sense that it covers only a finite domain on the coordinate plane (unlike a true Voronoi Diagram, which covers an infinite domain).

This class is under development and is subject to minor changes in its API and behavior.

Constructor Summary

Constructors

Constructor and Description
BoundedVoronoiDiagram(IIncrementalTin delaunayTriangulation) Constructs an instance of a Voronoi Diagram that corresponds to the input Delaunay Triangulation.
BoundedVoronoiDiagram(List<Vertex> vertexList, BoundedVoronoiBuildOptions options) Construct a Voronoi Diagram structure based on the input vertex set.

Method Summary

Modifier and Type	Method and Description
Rectangle2D	getBounds() Gets the bounds of the bounded Voronoi Diagram.
ThiessenPolygon	getContainingPolygon(double x, double y) Gets the polygon that contains the specified coordinate point (x,y).
List<IQuadEdge>	getEdges() Gets a list of the edges in the Voronoi Diagram.
int	getMaximumEdgeAllocationIndex() Gets the maximum index of the currently allocated edges.
List<ThiessenPolygon>	getPolygons() Gets a list of the polygons that comprise the Voronoi Diagram
Rectangle2D	getSampleBounds() Gets the bounds of the sample data set.
List<Vertex>	getVertices() Gets a list of the vertices that define the Voronoi Diagram.
List<Vertex>	getVoronoiVertices() Gets the vertices that were created to produce the Voronoi Diagram.
void	printDiagnostics(PrintStream ps) Prints diagnostic statistics for the Voronoi Diagram object.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BoundedVoronoiDiagram

public BoundedVoronoiDiagram(List<Vertex> vertexList,
                             BoundedVoronoiBuildOptions options)

Construct a Voronoi Diagram structure based on the input vertex set.

Parameters:

vertexList - a valid list of vertices

options - optional specification for setting build parameters or a null to use defaults.

BoundedVoronoiDiagram

public BoundedVoronoiDiagram(IIncrementalTin delaunayTriangulation)

Constructs an instance of a Voronoi Diagram that corresponds to the input Delaunay Triangulation.

Parameters:

delaunayTriangulation - a valid instance of a Delaunay Triangulation implementation.

Method Detail

printDiagnostics

public void printDiagnostics(PrintStream ps)

Prints diagnostic statistics for the Voronoi Diagram object.

Parameters:

ps - a valid print stream instance.

getBounds

public Rectangle2D getBounds()

Gets the bounds of the bounded Voronoi Diagram. If the associated Delaunay Triangulation included "skinny" triangles along its perimeter, the Voronoi Diagram's bounds may be substantially larger than those of the original input data set

Returns:

a valid rectangle

getSampleBounds

public Rectangle2D getSampleBounds()

Gets the bounds of the sample data set. These will usually be smaller than the bounds of the overall structure.

Returns:

a valid rectangle

getEdges

public List<IQuadEdge> getEdges()

Gets a list of the edges in the Voronoi Diagram. Applications are strongly cautioned against modifying these edges.

Returns:

a valid list of edges

getVertices

public List<Vertex> getVertices()

Gets a list of the vertices that define the Voronoi Diagram. This list is based on the input set, though in some cases coincident or nearly coincident vertices will be combined into a single vertex of type VertexMergerGroup.

Returns:

a valid list

getVoronoiVertices

public List<Vertex> getVoronoiVertices()

Gets the vertices that were created to produce the Voronoi Diagram. The output includes all circumcircle vertices that were computed when the structure was created. It does not include the original vertices from the input source

Returns:

a valid list of vertices

getPolygons

public List<ThiessenPolygon> getPolygons()

Gets a list of the polygons that comprise the Voronoi Diagram

Returns:

a valid list of polygons

getContainingPolygon

public ThiessenPolygon getContainingPolygon(double x,
                                            double y)

Gets the polygon that contains the specified coordinate point (x,y).

Note: Although a true Voronoi Diagram covers the entire plane, the Bounded Voronoi class is has a finite domain. If the specified coordinates are outside the bounds of this instance, no polygon will be found and a null result will be returned.

Parameters:

x - a valid floating point value

y - a valid floating point value

Returns:

the containing polygon or a null if none is found.

getMaximumEdgeAllocationIndex

public int getMaximumEdgeAllocationIndex()

Gets the maximum index of the currently allocated edges. This method can be used in support of applications that require the need to survey the edge set and maintain a parallel array or collection instance that tracks information about the edges. In such cases, the maximum edge index provides a way of knowing how large to size the array or collection.

Internally, Tinfour uses edge index values to manage edges in memory. The while there can be small gaps in the indexing sequence, this method provides a way of obtaining the absolute maximum value of currently allocated edges.

Returns:

a positive value or zero if the TIN is not bootstrapped.