D2

void setup()

{

  fullScreen();

  background(255);

  frameRate(120);;

}

​

void draw()

{

  int x = int(random(0,width/24));

  int y = int(random(0,height/24));

  noStroke();

  fill(random(200,255),random(100,255),random(100,255),random(255));

  rect(24*x,24*y,24,24);

}

​

void mouseDragged()

{

  int a = int(mouseX/24);

  int b = int(mouseY/24);

  noStroke();

  fill(#544ddc,95);

  rect(a*24,b*24,24,24);

}

void keyPressed()

{

  background(255);

}