//creating leaf animation with drawing lines 
class Leaf 
{ 
  float x, y, r, r2, sp, ysp; 
  int id; 
 
  Leaf( float px, float py, float pr, float psp, float pysp, int pid ) 
  { 
    x = px; 
    y = py; 
    r = pr; 
    r2 = r*r; 
    id = pid; 
    sp = psp; 
    ysp = pysp; 
  } 
  
  void update() 
  { 
    for(int i = 0; i< numLeaf; i++) 
    { 
      if(i != id) 
      { 
        intersect( this, Leafs[i] ); 
      } 
    } 
  } 
  
  void move() 
  { 
    x += sp; 
    y += ysp; 
    
    if(sp > 0) 
    { 
      if(x > width+r) 
      { 
        x = -r; 
      }   
    } 
    else 
    { 
      if(x < -r) 
      { 
        x = width+r; 
      } 
    } 
    if(ysp > 0) 
    { 
      if(y > height+r) 
      { 
        y = -r; 
      } 
    } 
    else 
    { 
      if(y < -r) 
      { 
        y = height+r; 
      } 
    } 
  } 
} 
 
 
void intersect( Leaf cA, Leaf cB ) 
{ 
  float dx = cA.x - cB.x; 
  float dy = cA.y - cB.y; 
  float d2 = dx*dx + dy*dy; 
  float d = sqrt( d2 ); 
 
  if ( d>cA.r+cB.r || d<abs(cA.r-cB.r) ) 
  { 
    return;  
  } 
  
  float a = (cA.r2 - cB.r2 + d2) / (2*d); 
  float h = sqrt( cA.r2 - a*a ); 
  float x2 = cA.x + a*(cB.x - cA.x)/d; 
  float y2 = cA.y + a*(cB.y - cA.y)/d; 
 
  float paX = x2 + h*(cB.y - cA.y)/d; 
  float paY = y2 - h*(cB.x - cA.x)/d; 
  float pbX = x2 - h*(cB.y - cA.y)/d; 
  float pbY = y2 + h*(cB.x - cA.x)/d; 
 
  stroke(dist(paX, paY, pbX, pbY)*4, 80); 
  line(paX, paY, pbX, pbY); 
}