/* tree2.sl
 *
 * draws regular tree, purturbs to produce vienlike pattern, see thru
 *
 */
#include "rmannotes.sl"

surface tree2( color treecolor = color(1,0,0);
	      float treenumber = 1)
	
	
{
  color paper, ink;
  float paper_opac, ink_opac;
  float ss, tt;

  float count;
  float hold;
  point center;
  float radius, width;
  float d;
  float noi;
  float fuzz = 0.025;
  float freq = 4;
  float noifreq = 5;
  float noiscale = 0.5;
  point p1, p2, p3, p4, p5;
  
 
 

  /* init */

  paper = 0;
  paper_opac = 0;
  count = 0;
  hold = .05;

  /* compute base noise */

  noi = noise(s * noifreq, t * noifreq);

  /* perturb ss, tt */

  ss = s + snoise(noi + 912) * noiscale;
  tt = t + snoise(noi + 333) * noiscale;


 /*create tiles*/

  ss = repeat(ss,treenumber);
  tt = repeat(tt,1) + noiscale/2.3;

 /*assign ink color*/
  
  ink = treecolor;
 
 
 /*draw tree*/
 
      p1 = (.5, 1, 0);
      p2 = (.5, 0.75, 0);
      width = .05;
      d = ptlined(p1, p2, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
  
 
  p3 = ( .25 + .1, .5 + .1, 0);
     
      width = .04;
      d = ptlined(p2, p3, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;

  p4 = ( 0 + .15, .5 + .1, 0);
     
      width = .03;
      d = ptlined(p3, p4, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;

  p5 = ( .25 - 0.2, .5 - .005, 0);
     
      width = .02;
      d = ptlined(p4, p5, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 
  
  p5 = ( .25 - 0.2, .5 + .2, 0);
     
      width = .02;
      d = ptlined(p4, p5, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 
  

  p4 = ( .25 + .1, .25 + .15, 0);
     
      width = .03;
      d = ptlined(p3, p4, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;

  p5 = ( .25 + .2, .25 + .05, 0);
     
      width = .02;
      d = ptlined(p4, p5, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 
  
  p5 = ( .25 , .25 + .05, 0);
     
      width = .02;
      d = ptlined(p4, p5, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 

   p3 = ( .75 - .1, .5 + .1, 0);
     
      width = .04;
      d = ptlined(p2, p3, (ss, tt, 0));
      ink_opac = (1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 
  p4 = ( 1 - .15, .5 + .1, 0);
     
      width = .03;
      d = ptlined(p3, p4, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
  
   p5 = ( .75 + 0.2, .5 - .005, 0);
     
      width = .02;
      d = ptlined(p4, p5, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 
  
  p5 = ( .75 + 0.2, .5 + .2, 0);
     
      width = .02;
      d = ptlined(p4, p5, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 
  
  p4 = ( .75 - .1, .25 + .15, 0);
     
      width = .03;
      d = ptlined(p3, p4, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
  
   p5 = ( .75 - .2, .25 + .05, 0);
     
      width = .02;
      d = ptlined(p4, p5, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 
  
  p5 = ( .75 , .25 + .05, 0);
     
      width = .02;
      d = ptlined(p4, p5, (ss, tt, 0));
      ink_opac =(1 - smoothstep(width / 2 - fuzz, width / 2 + fuzz, d));
      paper = mix(paper, ink, ink_opac);
      paper_opac = paper_opac + ink_opac;
 

  /* output */
 
  
  Oi = paper_opac;
  Ci = paper_opac * paper;
}