text: function TestDamBreak() {
    camera.position.y = 2;
    camera.position.z = 3;
    var bodyDef = new b2BodyDef();
    var ground = world.CreateBody(bodyDef);
  
    var chainShape = new b2ChainShape();
    chainShape.vertices.push(new b2Vec2(-2, 0));
    chainShape.vertices.push(new b2Vec2(2, 0));
    chainShape.vertices.push(new b2Vec2(2, 4));
    chainShape.vertices.push(new b2Vec2(-2, 4));
  
    chainShape.CreateLoop();
    ground.CreateFixtureFromShape(chainShape, 0);
  
    var shape = new b2PolygonShape;
    shape.SetAsBoxXYCenterAngle(0.8, 1, new b2Vec2(-1.2, 1.01), 0);
  
    var psd = new b2ParticleSystemDef();
    psd.radius = 0.025;
    psd.dampingStrength = 0.2;
  
    var particleSystem = world.CreateParticleSystem(psd);
  
    var pgd = new b2ParticleGroupDef();
    pgd.color.Set(80, 140, 200, 130);
    pgd.shape = shape;
    var group = particleSystem.CreateParticleGroup(pgd);
  }
  