@Override
    public void initialize(RenderManager rm, ViewPort vp) {
        reshape(vp, vp.getCamera().getWidth(), vp.getCamera().getHeight());
        viewPort.setOutputFrameBuffer(fb);
        guiViewPort.setClearFlags(true, true, true);

        guiNode.attachChild(display1);
        guiNode.attachChild(display2);
        guiNode.attachChild(display3);
        guiNode.attachChild(display4);
        guiNode.updateGeometricState();
    }
Create a cube with the specified color,
using a custom unshaded material that outputs 4 textures:<ul>
<li>red channel only to location 0,</li>
<li>green channel only to location 1,</li>
<li>blue channel only to location 2,</li>
<li>merged RGB to location 3.</li></ul>

@param color the desired albedo color (alias created)
@return a new Geometry with no parent
jme3-examples/src/main/java/jme3test/post/TestMultiRenderTarget.java