/* shinymetal.sl - Standard metal with environment mapping for
 * RenderMan Interface.
 * (c) Copyright 1988, Pixar.
 *
 * The RenderMan (R) Interface Procedures and RIB Protocol are:
 *     Copyright 1988, 1989, Pixar.  All rights reserved.
 * RenderMan (R) is a registered trademark of Pixar.
 */


surface
shinymetal (float Ka = 1;
	    float Ks = 1;
	    float Kr = 1;
	    float roughness = .1;
	    string texturename = "";)
{
  normal Nf;
  vector V, D;
  color env;

  V = normalize(I);
  Nf = faceforward (normalize(N),V);
  D = reflect (V, Nf);
  D = vtransform ("world", D);

  if (texturename != "")
      env = Kr * color environment (texturename, D);
  else env = 0;

  Oi = Os;
  Ci = Os * Cs * (Ka*ambient() + Ks*specular(Nf,-V,roughness) + env);
}