public boolean isFaceCullFlippable() {
        return cullMode == FaceCullMode.Front || cullMode == FaceCullMode.Back;
    }
Checks if the face cull mode is "flippable".
<p>The cull mode is flippable when it is either {@code Front} or {@code Back}.
@return
jme3-core/src/main/java/com/jme3/material/RenderState.java