* @param kd The diffuse reflectance <code>Spectrum</code>.
* @param ks The specular reflectance <code>Spectrum</code>.
* @param n The sharpness of the specular reflectance lobe.
*/
public ModifiedPhongMaterial(Spectrum kd, Spectrum ks, double n) {
this(new UniformPainter(kd), new UniformPainter(ks), n);
}