// The current coordinates of the ball, starting at the center (in setup)
float x, y;
// The current color of the ball, and whether it's increasing or decreasing
int gray=255, dgray=-1;
// The current size of the ball, and how much it's increasing or decreasing
float sz=5, dsz=0.1;

void setup()
{
  size(400,400);
  smooth();
  noStroke();
  background(0);
  x=width/2; y=height/2;
}

void draw()
{
  fill(0,3);
  rect(0,0,width,height);
  fill(gray);
  ellipse(x,y,sz,sz);
  // Move the position by random steps in x and y
  x += random(-10,10);
  y += random(-10,10);
  // Increase/decrease the color, changing direction at the extremes
  gray += dgray;
  // too large or too small, go the other way
  if (gray <= 128) dgray = 1;
  else if(gray >= 255) dgray = -1;
  // Increase/decrease the size, changing direction at the extremes
  sz += dsz;
  // if too large or too small, go the other way
  if (sz <= 2 || sz >= 15) dsz = -dsz;
}

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