@Override
    public void write(JmeExporter ex) throws IOException {
        super.write(ex);
        OutputCapsule oc = ex.getCapsule(this);
        oc.write(shadowRenderer, "shadowRenderer", null);
    }
Sets the light to use to cast shadows.

@param light the SpotLight
jme3-core/src/main/java/com/jme3/shadow/SpotLightShadowFilter.java