PhysBall ball;

void setup()
{
  size(400,400);
  smooth();
  noStroke();
  background(0);

  ball = new PhysBall(width/2,height/2,color(255)); 
}

void draw()
{
  fill(0,25); noStroke();
  rect(0,0,width,height);
  ball.draw();
  ball.update();
}

void keyPressed()
{
  if (key=='r') { // randomize the ball
    ball.x = width/2;
    ball.y = height/2;
    ball.vx = random(-5,5);
    ball.vy = random(-5,5);
  }
  else if (key=='g') { // half as much gravity
    ball.gravity *= 0.5;
    println("gravity:"+ball.gravity);
  }
  else if (key=='G') {
    ball.gravity *= 2;
    println("gravity:"+ball.gravity);
  }
  else if (key=='d') { // half as much drag (measured as 1-d)
    ball.drag = 1 - (1-ball.drag)*0.5;
    println("drag:"+ball.drag);
  }
  else if (key=='D') {
    ball.drag = 1 - (1-ball.drag)*2;
    println("drag:"+ball.drag);
  }
  else if (key=='f') { // half as much damping
    ball.frict = 1 - (1-ball.frict)*0.5;
    println("y friction:"+ball.frict);
  }
  else if (key=='F') {
    ball.frict = 1 - (1-ball.frict)*2;
    println("y friction:"+ball.frict);
  }
}

// START NO NOTES
// code used to capture screenshots
void keyReleased() {
  if(key == '`' && !online) save("sketch.png");
}