Koch snowflake

void setup(){

  size(500,500);

  background(255);

}

​

void draw(){

  background(255);

  tri(new PVector(50, 375), new PVector(450, 375), new PVector(250,25));

}

​

void bla(PVector s,PVector e,int deep){

   float d = dist(s.x, s.y, e.x, e.y);

   if(d < 5){

     line(s.x,s.y,e.x,e.y);

     return;

   }

   PVector mid1 = PVector.lerp(s, e, 1.0/3);

   PVector mid2 = PVector.lerp(s, e, 2.0/3);

   PVector midonLine = PVector.lerp(s, e, 0.5);

   PVector target = PVector.sub(mid2,mid1);

   target.rotate(PI/3);

   target.add(mid1);

   if(frameCount < 60*deep) {

     float dt = frameCount%(60);

     PVector mid = PVector.lerp(midonLine,target,dt/60.0);

     line(s.x,s.y,mid1.x,mid1.y);

     line(mid.x,mid.y,mid1.x,mid1.y);

     line(mid.x,mid.y,mid2.x,mid2.y);

     line(e.x,e.y,mid2.x,mid2.y);

   }

   else{

     bla(s,mid1,deep+1);

     bla(mid1,target,deep+1);

     bla(target,mid2,deep+1);

     bla(mid2,e,deep+1);    

   }

}

​

void tri(PVector p1, PVector p2, PVector p3){

  bla(p1,p2,1);

  bla(p2,p3,1);

  bla(p3,p1,1);

}