// 

String title=  "Flocks of birds";
String author=  "Hugo Bonilla";

int n; 
float x = 100; 
float y = 150;
float w = 15;
float h = 15; 
float pairs= random(3,10);
float shrink= .08 ; 


void setup() {
    size (600,400);
    reset(); 
}

void draw(){ 
    background(94,203,62);
    text( title, width/3, 30 );
    text(author, 20, height-20);

    flock( n , x ,y ,w ,h);
    x+= random (20);
    if (x>width*1.5) x=0;
    y = y-10 + random(20); 

}
void bird( float x ,float y ,float w ,float h) {
      fill(0);
    triangle(x,y, x-w , y-h/3, x-w, y+h/3 ); 
    }

void flock( int n , float x, float y, float w , float h) {
    float xx= x; 
    float up =0;  
    float ww=w; 
    float dy = h/3;
    float yy= y;
    dy= h/3; 
    dy += h/3;
   //lead bird 
    bird ( xx ,y ,w,h);
    
   // make flock of birds 
    for (int j=0;j<pairs;j++) {
      
    xx= xx-2*w;
    up=  up + h;
    ww=  ww * 0.8;
    bird ( xx ,y- up ,ww,h); // up 
    bird ( xx ,y+ up ,ww,h); // down 
  }
}


void reset() {  
  x=0;
  y= random(height/2, height); 
  pairs= int ( random(3,10));
}

void keyPressed() {
  if (key =='r') reset();
}