ContactID.java

/*
 * The MIT License (MIT)
 *
 * FXGL - JavaFX Game Library
 *
 * Copyright (c) 2015-2017 AlmasB (almaslvl@gmail.com)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
/*
 * JBox2D - A Java Port of Erin Catto's Box2D
 * 
 * JBox2D homepage: http://jbox2d.sourceforge.net/
 * Box2D homepage: http://www.box2d.org
 * 
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 * 
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 * 
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 */
package org.jbox2d.collision;

/**
 * Contact ids to facilitate warm starting. Note: the ContactFeatures class is just embedded in here
 */
public class ContactID implements Comparable<ContactID> {

    public static enum Type {
        VERTEX, FACE
    }

    public byte indexA;
    public byte indexB;
    public byte typeA;
    public byte typeB;

    public int getKey() {
        return ((int) indexA) << 24 | ((int) indexB) << 16 | ((int) typeA) << 8 | ((int) typeB);
    }

    public boolean isEqual(final ContactID cid) {
        return getKey() == cid.getKey();
    }

    public ContactID() {
    }

    public ContactID(final ContactID c) {
        set(c);
    }

    public void set(final ContactID c) {
        indexA = c.indexA;
        indexB = c.indexB;
        typeA = c.typeA;
        typeB = c.typeB;
    }

    public void flip() {
        byte tempA = indexA;
        indexA = indexB;
        indexB = tempA;
        tempA = typeA;
        typeA = typeB;
        typeB = tempA;
    }

    /**
     * zeros out the data
     */
    public void zero() {
        indexA = 0;
        indexB = 0;
        typeA = 0;
        typeB = 0;
    }

    @Override
    public int compareTo(ContactID o) {
        return getKey() - o.getKey();
    }
}