public void setVxOffset(float vxOffset) {
        this.vxOffset = vxOffset;
        if (material != null) {
            material.setFloat("VxOffset", this.vxOffset);
        }
    }
set to 0.0f for higher quality

@param reduceMul the desired value (default=0.125)
jme3-effects/src/main/java/com/jme3/post/filters/FXAAFilter.java