/*Wooksang's dirty shader for construction*/
 

#include "rmannotes.sl" 
surface
bug_shader(
      float Ks=0.3,Kd=0.9,Ka=0.1,freqR = 6,Km=0.02,roughness=.1;
      varying point Pr = 0;
      color specularcolor=1;
      color First=color(1,0.079,0),
      Second = color(1,1,1),
      Third=color(0.439,0.356,0.297);)
{
  color surface_color,layer_color=color(1,1,1);
  float layer_opac,r,freq=5,grey=0;
  point PP,newP;
  float size=2, i,opac=0,opac1=0;
  normal Nf;
  vector V;

  Nf = faceforward( normalize(N), I );
  V = -normalize(I);

  surface_color=First;
  layer_opac=0;

/*lay_line*/
  PP = transform("shader", P);
  PP+= noise(PP*4+3)*0.5;
  r = distance (point (0,ycomp(PP),zcomp(PP)),point(1,1,1));
  r = repeat(r+snoise(r*4),freq);
  layer_color = color(1,1,1);
  layer_opac = (step(0.6,r)-step(0.8,r))*0.07;
  surface_color = blend(surface_color, layer_color, layer_opac);


/*layer #1*/
  PP=transform("shader",P);
  surface_color=Third;
  for(i=0;i<freqR;i+=1){
    layer_opac+=abs(0.6-noise(PP*size))/size;
    size*=2;
    opac=layer_opac;
    layer_color=spline(layer_opac,First,First,First,Second,Second,Third,Third);
    surface_color=blend(surface_color,layer_color,layer_opac);
  }

/* layer #2*/  
  layer_color=color(0,0,0);
  for(i=0;i<freqR;i+=1){
    layer_opac+=abs(0.7-noise(PP*size))/size;
    size*=2; 
    opac1=layer_opac;
    surface_color=blend(surface_color,layer_color,layer_opac);
    }
  grey = 0.299*comp(surface_color,0)+
         0.587*comp(surface_color,1)+
         0.114*comp(surface_color,2);
/* bump */
  newP = calculatenormal(P+grey*Km*normalize(N));
  Nf = faceforward(normalize(newP),I);

Ci = Os * ( surface_color * (Ka*ambient()+Kd*diffuse(Nf))+
	      specularcolor * Ks * specular(Nf,V,roughness)*(1-opac));
}