@Override
            protected void onEnable() {}
Test PBR lighting with different parameters

@param testName The name of the test (used for screenshot filename)
@param roughness The roughness value to use
@param updateLight Whether to update the directional light to match camera direction
jme3-screenshot-tests/src/test/java/org/jmonkeyengine/screenshottests/light/pbr/TestPBRLighting.java