@Override
    public void setSpatial(Spatial spatial) {
        if (this.spatial != null && spatial != null && spatial != this.spatial) {
            throw new IllegalStateException("This control has already been added to a Spatial");
        }
        this.spatial = spatial;
        if (spatial != null) spatial.addLight(this);
    }
Returns true if savable results are required by this control.

@return true if savable results are required.
jme3-core/src/main/java/com/jme3/environment/EnvironmentProbeControl.java