public void setNormalTexture(Texture2D normalTexture) {
        this.normalTexture = normalTexture;
        normalTexture.setWrap(WrapMode.Repeat);
        if (material != null) {
            material.setTexture("NormalMap", normalTexture);
        }
    }
Sets the normal texture.

@param normalTexture the normal texture.
jme3-effects/src/main/java/com/jme3/water/WaterFilter.java