Moving the mouse changes the position and size of each box.
Original Processing.org Example: Mouse2D
// All Examples Written by Casey Reas and Ben Fry
// unless otherwise stated.
void setup()
{
size(200, 200);
noStroke();
colorMode(RGB, 255, 255, 255, 100);
rectMode(CENTER);
}
void draw()
{
background(51);
fill(255, 80);
rect(mouseX, height/2, mouseY/2+10, mouseY/2+10);
fill(255, 80);
rect(width-mouseX, height/2, ((height-mouseY)/2)+10, ((height-mouseY)/2)+10);
}