#define TEST_DEFINE 3.14
surface plastic (float Ka = 1, Kd = 0.5, Ks = 0.5, roughness = 0.1;
color specularcolor = 1;) {
normal Nf = faceforward (normalize(N),I);
Ci = Cs * (Ka*ambient() + Kd*diffuse(Nf)) + specularcolor * Ks *
specular(Nf,-normalize(I),roughness);
Oi = Os;
Ci *= Oi;
}