jv.geom

Class PgUtil

java.lang.Object

jv.geom.PgUtil

public class PgUtil
extends java.lang.Object

Utility programs for geometry classes which operate on primitive data.

Author:

Konrad Polthier

Version:

06.10.03, 1.10 revised (kp) Superclass changed to java.lang.Object.
10.09.98, 1.00 created (kp)

Constructor Summary

Constructors

Constructor and Description
PgUtil()

Method Summary

Modifier and Type	Method and Description
static PiVector[]	triangulate(PdVector[] polygon) Deprecated. use triangulate(PdVector[], int)
static PiVector[]	triangulate(PdVector[] polygon, int numVertices) Triangulate a given simple closed, nearly planar polygon.

Methods inherited from class java.lang.Object

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

Constructor Detail

PgUtil

public PgUtil()

Method Detail

triangulate

public static PiVector[] triangulate(PdVector[] polygon,
                                     int numVertices)

Triangulate a given simple closed, nearly planar polygon. It is assumed that the 0-th and (numVertices-1)-th vertex are connected by an additional edge which closes the given sequence of vertices.

Method successively removes the vertex with the smallest interior angle. Method can handle non-convex polygons.

Polygon may have vertices of arbitrary ambient dimension larger than one. First and last vertex are implicitly connected to obtain a closed polygon.

ToDo: But until now it cannot handle situations where the edge introduced by removing a vertex intersects the polygon somewhere else. To solve this problem the above method checkTriangleCut must be employed.

Parameters:

polygon - Array with vertices described a closed polygon in R^n.

numVertices - Number of used entries in vertex array.

Since:

JavaView 2.36

Author:

Konrad Polthier

Version:

07.11.02, 1.40 revised (ur) No decrementing the number of vertices in this method.
04.09.02, 1.30 revised (kp) Include length of used part of array as argument.
12.02.01, 1.20 revised (kp) Bugs removed in star-shaped polygons, argument orient removed.
10.06.98, 1.10 revised (kp) rewritten for Java.
10.06.90, 1.00 created (kp) original Fortran version "triplg.f".

triangulate

public static PiVector[] triangulate(PdVector[] polygon)

Deprecated. use triangulate(PdVector[], int)

Triangulate a given simple closed, nearly planar polygon. Method successively removes the vertex with the smallest interior angle. Method can handle non-convex polygons.

Polygon may have vertices of arbitrary ambient dimension larger than one. First and last vertex are implicitly connected to obtain a closed polygon.

ToDo: But until now it cannot handle situations where the edge introduced by removing a vertex intersects the polygon somewhere else. To solve this problem the above method checkTriangleCut must be employed.

Parameters:

polygon - Array with vertices described a closed polygon in R^n.

Author:

Konrad Polthier

Version:

12.02.01, 1.20 revised (kp) Bugs removed in star-shaped polygons, argument orient removed.
10.06.98, 1.10 revised (kp) rewritten for Java.
10.06.90, 1.00 created (kp) original Fortran version "triplg.f".