/** Surface properties, this base class does a single color,
 * extend class and override getColor for fancy 3D textures
 * (should use surface mapping instead for moving objects)
 * @author: Phil Gage
 */
class Material {
    Color color;        // base color
    double kd = 1.0;    // diffuse reflection coefficient
    double ks = 0.0;    // specular reflection coefficient
    double kt = 0.0;    // transmission coefficient
    double ir = 1.0;    // index of refraction
    double specular = 0.0;   // Phong specular highlight exponent

    Material (Color color) {
        this.color = color;
    }

    /** Return material color at a point, override for textures */
    Color getColor (Point point) {
        return color;
    }
}