@Override
    public void simpleUpdate(float tpf) {
        leftScene.updateLogicalState(tpf);
        leftScene.updateGeometricState();
    }
Simple application to test split-screen rendering. Clicking with LMB toggles
between a single camera/viewport (cam) and split screen (leftCam plus
rightCam). See issue #357.
jme3-examples/src/main/java/jme3test/renderer/TestSplitScreen.java