public void setFoamHardness(float foamHardness) {
        this.foamHardness = foamHardness;
        if (material != null) {
            material.setFloat("FoamHardness", foamHardness);
        }
    }
Sets the foam hardness : How much the foam will blend with the shore to avoid hard edged water plane.
Default is 1.0

@param foamHardness the desired hardness (default=1)
jme3-effects/src/main/java/com/jme3/water/WaterFilter.java