cs252proj.api
Interface PolygonPathFinder

public interface PolygonPathFinder

An interface for finding the shortest path within a simple polygonal subdivision.

Method Summary

void	execute(jdsl.map.api.InspectableEmbeddedPlanarGraph g) Initializes the PolygonPathFinder with the given embedded planar graph.
jdsl.core.api.ObjectIterator	getPath(jdsl.geomobj.api.Point2D p1, jdsl.geomobj.api.Point2D p2) Finds a path within the polygonal subdivision.

Method Detail

execute

public void execute(jdsl.map.api.InspectableEmbeddedPlanarGraph g)
             throws java.lang.ClassCastException

Initializes the PolygonPathFinder with the given embedded planar graph.

Parameters:

g - the embedded planar graph on which to search.

Throws:

java.lang.ClassCastException - if the embedded planar graph does not contain Point2Ds at its vertices.

getPath

public jdsl.core.api.ObjectIterator getPath(jdsl.geomobj.api.Point2D p1,
                                            jdsl.geomobj.api.Point2D p2)
                                     throws java.lang.IllegalStateException

Finds a path within the polygonal subdivision.

Parameters:

p1 - the first point in the path.

p2 - the last point in the path.

Returns:

an iterator over the sequence of Point2Ds making up the path, or null if no path exists, or one of the points lies on the graph.

Throws:

java.lang.IllegalStateException - if execute was not called first.