/* FHKalotte - surface shader to map a polar map to a rectangle in shading 
               coordinates (s,t)
               Based on the painted plastic shader.

   Written by Florian Hars, 1996 (GPL Version 2 applies)
*/

surface FHKalotte (
		 float Ks =.5,
		       Kd =.5,
		       Ka = 1,
		       roughness = .1;
		 color specularcolor = 1;
		 string mapname = "kalotte.tiff")
{
   point Nf = faceforward(N,I);
   
   Ci = color texture(mapname, .5 +.5*(1-t)*sin(6.28318 * s),
		               .5 -.5*(1-t)*cos(6.28318 * s));
   Oi=Os;
   Ci=Os*(Ci * (ambient() + Kd*diffuse(Nf)) 
	  + specularcolor * Ks *specular(Nf, -I,roughness));
}