engine/src/jbullet/com/jme3/bullet/collision/shapes/MeshCollisionShape.java

/*
 * Copyright (c) 2009-2010 jMonkeyEngine
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
 *   may be used to endorse or promote products derived from this software
 *   without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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package com.jme3.bullet.collision.shapes;

import com.bulletphysics.collision.shapes.BvhTriangleMeshShape;
import com.bulletphysics.collision.shapes.IndexedMesh;
import com.bulletphysics.collision.shapes.TriangleIndexVertexArray;
import com.jme3.bullet.util.Converter;
import com.jme3.export.InputCapsule;
import com.jme3.export.JmeExporter;
import com.jme3.export.JmeImporter;
import com.jme3.export.OutputCapsule;
import com.jme3.math.Vector3f;
import com.jme3.scene.Mesh;
import java.io.IOException;
import java.nio.ByteBuffer;

/**
 * Basic mesh collision shape
 * @author normenhansen
 */
public class MeshCollisionShape extends CollisionShape {

    protected int numVertices, numTriangles, vertexStride, triangleIndexStride;
    protected ByteBuffer triangleIndexBase, vertexBase;
    protected IndexedMesh bulletMesh;

    public MeshCollisionShape() {
    }

    /**
     * creates a collision shape from the given TriMesh
     * @param mesh the TriMesh to use
     */
    public MeshCollisionShape(Mesh mesh) {
        createCollisionMesh(mesh, new Vector3f(1, 1, 1));
    }

    private void createCollisionMesh(Mesh mesh, Vector3f worldScale) {
        this.scale = worldScale;
        bulletMesh = Converter.convert(mesh);
        this.numVertices = bulletMesh.numVertices;
        this.numTriangles = bulletMesh.numTriangles;
        this.vertexStride = bulletMesh.vertexStride;
        this.triangleIndexStride = bulletMesh.triangleIndexStride;
        this.triangleIndexBase = bulletMesh.triangleIndexBase;
        this.vertexBase = bulletMesh.vertexBase;
        createShape();
    }

    /**
     * creates a jme mesh from the collision shape, only needed for debugging
     */
    public Mesh createJmeMesh(){
        return Converter.convert(bulletMesh);
    }

    public void write(JmeExporter ex) throws IOException {
        super.write(ex);
        OutputCapsule capsule = ex.getCapsule(this);
        capsule.write(numVertices, "numVertices", 0);
        capsule.write(numTriangles, "numTriangles", 0);
        capsule.write(vertexStride, "vertexStride", 0);
        capsule.write(triangleIndexStride, "triangleIndexStride", 0);

        capsule.write(triangleIndexBase.array(), "triangleIndexBase", new byte[0]);
        capsule.write(vertexBase.array(), "vertexBase", new byte[0]);
    }

    public void read(JmeImporter im) throws IOException {
        super.read(im);
        InputCapsule capsule = im.getCapsule(this);
        numVertices = capsule.readInt("numVertices", 0);
        numTriangles = capsule.readInt("numTriangles", 0);
        vertexStride = capsule.readInt("vertexStride", 0);
        triangleIndexStride = capsule.readInt("triangleIndexStride", 0);

        triangleIndexBase = ByteBuffer.wrap(capsule.readByteArray("triangleIndexBase", new byte[0]));
        vertexBase = ByteBuffer.wrap(capsule.readByteArray("vertexBase", new byte[0]));
        createShape();
    }

    protected void createShape() {
        bulletMesh = new IndexedMesh();
        bulletMesh.numVertices = numVertices;
        bulletMesh.numTriangles = numTriangles;
        bulletMesh.vertexStride = vertexStride;
        bulletMesh.triangleIndexStride = triangleIndexStride;
        bulletMesh.triangleIndexBase = triangleIndexBase;
        bulletMesh.vertexBase = vertexBase;
        bulletMesh.triangleIndexBase = triangleIndexBase;
        TriangleIndexVertexArray tiv = new TriangleIndexVertexArray(numTriangles, triangleIndexBase, triangleIndexStride, numVertices, vertexBase, vertexStride);
        cShape = new BvhTriangleMeshShape(tiv, true);
        cShape.setLocalScaling(Converter.convert(getScale()));
        cShape.setMargin(margin);
    }
}