ConstantVolumeJointDef.java

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 * Copyright (c) 2011, Daniel Murphy
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package org.jbox2d.dynamics.joints;

import org.jbox2d.dynamics.Body;

/**
 * Definition for a {@link ConstantVolumeJoint}, which connects a group a bodies together
 * so they maintain a constant volume within them.
 */
public class ConstantVolumeJointDef extends JointDef {
	Body[] bodies;
	public float frequencyHz;
	public float dampingRatio;
	//public float relaxationFactor;//1.0 is perfectly stiff (but doesn't work, unstable)

	public ConstantVolumeJointDef() {
		type = JointType.CONSTANT_VOLUME;
		bodies = new Body[0];
		//relaxationFactor = 0.9f;
		collideConnected = false;
		frequencyHz = 0.0f;
		dampingRatio = 0.0f;
	}

	public void addBody(final Body b) {
		final Body[] tmp = new Body[bodies.length+1];
		System.arraycopy(bodies, 0, tmp, 0, bodies.length);
		tmp[bodies.length] = b;
		bodies = tmp;
		if (tmp.length == 1) {
			bodyA = b;
		}
		if (tmp.length == 2) {
			bodyB = b;
		}
	}
}