public void setValue(float value) {
        this.value = value;       
        if (material != null) {
            material.setFloat("Value", value);
        }
    }
Sets the fade value.
Can be used to force all black or all scene.

@param value the desired value (default=1)
jme3-effects/src/main/java/com/jme3/post/filters/FadeFilter.java