com.sun.j3d.utils.geometry

Class EarClip

java.lang.Object

com.sun.j3d.utils.geometry.EarClip

 class EarClip
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
EarClip()

Method Summary

Methods

Modifier and Type	Method and Description
(package private) static void	classifyAngles(Triangulator triRef, int ind) Classifies all the internal angles of the loop referenced by ind.
(package private) static void	classifyEars(Triangulator triRef, int ind)
(package private) static boolean	clipEar(Triangulator triRef, boolean[] done) This is the main function that drives the ear-clipping.
(package private) static boolean	isEar(Triangulator triRef, int ind2, int[] ind1, int[] ind3, double[] ratio) This function checks whether a diagonal is valid, that is, whether it is locally within the polygon, and whether it does not intersect any other segment of the polygon.

Methods inherited from class java.lang.Object

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

Constructor Detail

EarClip

EarClip()

Method Detail

classifyAngles

static void classifyAngles(Triangulator triRef,
                  int ind)

Classifies all the internal angles of the loop referenced by ind. the following classification is used: 0 ... if angle is 180 degrees 1 ... if angle between 0 and 180 degrees 2 ... if angle is 0 degrees -1 ... if angle between 180 and 360 degrees -2 ... if angle is 360 degrees

classifyEars

static void classifyEars(Triangulator triRef,
                int ind)

isEar

static boolean isEar(Triangulator triRef,
            int ind2,
            int[] ind1,
            int[] ind3,
            double[] ratio)

This function checks whether a diagonal is valid, that is, whether it is locally within the polygon, and whether it does not intersect any other segment of the polygon. also, some degenerate cases get a special handling.

clipEar

static boolean clipEar(Triangulator triRef,
              boolean[] done)

This is the main function that drives the ear-clipping. it obtains an ear from set of ears maintained in a priority queue, clips this ear, and updates all data structures appropriately. (ears are arranged in the priority queue (i.e., heap) according to a quality criterion that tries to avoid skinny triangles.)