/* paisley.sl
 *
 *   creates two layers of paisleys with a third dotted layer
 *    taking the usual parameters
 */
#include "/usr/local/accad/shaders/rmannotes.sl"

surface paisley(
	      float hfreq1 = 4, vfreq1 = 4, hfreq2 = 3, vfreq2 = 3;
              float angle1 = 0.5, angle2 = 0.0;
              float Ka = 0.5, Kd = 0.5, Ks = 0.5, roughness = 0.1;
              color specularcolor = 1;
              )
{
  color surface_color, layer_color;
  color surface_opac, layer_opac;
  float fuzz = 0.025;
  point center1, center2, center3;
  float radius1, radius2, radius3;
  float d1, d2, d3;
  float x1, y1, lo1, lo2, lo3;

  float ss, tt, sss, ttt;

  /* background layer */
  surface_color = Cs;
  surface_opac = Os;


  /* lower paisley layer */

  layer_color = color (0.5, 0.1, 0.95);
  x1 = noise(s)*0.5;

  sss = repeat(s, hfreq1);
  ttt = repeat(t, vfreq1);

  rotate2d(sss, ttt, angle1, 0.5, 0.5, ss, tt);

  center1 = (0.5, 0.5, 0.0);
  radius1 = 0.5;
  d1 = distance(center1, (ss, tt, 0));

  center2 = (x1, 0.5, 0.0);
  radius2 = x1;
  d2 = distance(center2, (ss, tt, 0));

  center3 = (0.5 + x1, 0.5, 0.0);
  radius3 = 0.5 - x1;
  d3 = distance(center3, (ss, tt, 0));

   lo1 = (1 - smoothstep(radius1 - fuzz, radius1, d1)) *
               (1 - smoothstep(0.5 - fuzz, 0.5, tt));
   lo2 = 1 - smoothstep(radius2 - fuzz, radius2, d2);

   lo3 = 1 - smoothstep(radius3 - fuzz, radius3, d3);

   layer_opac = difference(union(lo1, lo2), lo3);

  surface_color = blend(surface_color, layer_color, layer_opac);


 /* upper paisley layer */
  layer_color = color (0.1, 0.05, 0.95);
  x1 = noise(t)*0.5;

  sss = repeat(-s, hfreq2);
  ttt = repeat(-t, vfreq2);

  rotate2d(sss, ttt, angle2, 0.5, 0.5, ss, tt);

  center1 = (0.5, 0.5, 0.0);
  radius1 = 0.5;
  d1 = distance(center1, (ss, tt, 0));

  center2 = (x1, 0.5, 0.0);
  radius2 = x1;
  d2 = distance(center2, (ss, tt, 0));

  center3 = (0.5 + x1, 0.5, 0.0);
  radius3 = 0.5 - x1;
  d3 = distance(center3, (ss, tt, 0));

   lo1 = (1 - smoothstep(radius1 - fuzz, radius1, d1)) *
               (1 - smoothstep(0.5 - fuzz, 0.5, tt));
   lo2 = 1 - smoothstep(radius2 - fuzz, radius2, d2);

   lo3 = 1 - smoothstep(radius3 - fuzz, radius3, d3);

   layer_opac = difference(union(lo1, lo2), lo3)*0.5;

  surface_color = blend(surface_color, layer_color, layer_opac);


/* dot layer */

 layer_color = color (0.596, 0.984, 0.596);


 center1 = (x1, 0.5, 0);
 radius1 = x1 / 5.0;

 d1 = distance(center1, (ss, tt, 0));
 layer_opac = (1 - smoothstep(radius1 - fuzz, radius1, d1))* 0.8;

  surface_color = blend(surface_color, layer_color, layer_opac);


  /* output */

  Oi = surface_opac;
  Ci = surface_opac * surface_color
       * (Ka*ambient() + Kd*diffuse(Nf)) +
          specularcolor * Ks * specular(Nf, V, roughness);
}