public void addMatParamOverride(MatParamOverride override) {
        if (override == null) {
            throw new IllegalArgumentException("override cannot be null");
        }
        localOverrides.add(override);
        setMatParamOverrideRefresh();
    }
Adds a local material parameter override.

@param override The override to add.
@see MatParamOverride
jme3-core/src/main/java/com/jme3/scene/Spatial.java