@Override
protected void initGame() {
GameStateManager.create();
rootNode = new Node("rootNode");
ZBufferState buf = display.getRenderer().createZBufferState();
buf.setEnabled(true);
buf.setFunction(ZBufferState.TestFunction.LessThanOrEqualTo);
rootNode.setRenderState(buf);
PointLight light = new PointLight();
light.setDiffuse(new ColorRGBA(0.75f, 0.75f, 1.0f, 0.75f));
light.setAmbient(new ColorRGBA(0.1f, 0.1f, 0.1f, 1.0f));