Manifold.java

package com.badlogic.gdx.physics.box2d;

import com.badlogic.gdx.math.Vector2;

public class Manifold {
        final World world;
        long addr;
        final ManifoldPoint[] points = new ManifoldPoint[] { new ManifoldPoint(), new ManifoldPoint() };
        final Vector2 localNormal = new Vector2();
        final Vector2 localPoint = new Vector2();       
        
        final int[] tmpInt = new int[2];
        final float[] tmpFloat = new float[4];
        
        protected Manifold(World world, long addr) {
                this.world = world;
                this.addr = addr;
        }
        
        public ManifoldType getType() {
                int type = jniGetType(addr);
                if(type == 0) return ManifoldType.Circle;
                if(type == 1) return ManifoldType.FaceA;
                if(type == 2) return ManifoldType.FaceB;
                return ManifoldType.Circle;
        }
        
        private native int jniGetType(long addr);
        
        public int getPointCount() {
                return jniGetPointCount(addr);
        }
        
        private native int jniGetPointCount(long addr);
        
        public Vector2 getLocalNormal() {
                jniGetLocalNormal(addr, tmpFloat);
                localNormal.set(tmpFloat[0], tmpFloat[1]);
                return localNormal;
        }
        
        private native void jniGetLocalNormal(long addr, float[] values);
        
        public Vector2 getLocalPoint() {
                jniGetLocalPoint(addr, tmpFloat);
                localPoint.set(tmpFloat[0], tmpFloat[1]);
                return localPoint;
        }
        
        private native void jniGetLocalPoint(long addr, float[] values);
        
        public ManifoldPoint[] getPoints() {
                int count = jniGetPointCount(addr);
                
                for(int i = 0; i < count; i++) {
                        int contactID = jniGetPoint(addr, tmpFloat, i);
                        ManifoldPoint point = points[i];
                        point.contactID = contactID;
                        point.localPoint.set(tmpFloat[0], tmpFloat[1]);
                        point.normalImpulse = tmpFloat[2];
                        point.tangentImpulse = tmpFloat[3];
                }
                
                return points;
        }
        
        private native int jniGetPoint(long addr, float[] values, int i);       
        
        public class ManifoldPoint {
                public final Vector2 localPoint = new Vector2();
                public float normalImpulse;
                public float tangentImpulse;
                public int contactID = 0;
                
                public String toString() {
                        return "id: " + contactID + ", " + localPoint + ", "  + normalImpulse + ", " + tangentImpulse;
                }
        }
        
        public enum ManifoldType {
                Circle,
                FaceA,
                FaceB
        }       
}