// Copy the part of the screen to be overlapped by the window
// and draw a transparent rectangle over it.
event.load
screen.copyTo.main(100,100,200,200,0,0)
window.main.pos.now(100,100,200,200)
draw.main.rect(0,0,200,200,num.rgb(100,0,0),0,40)
draw.main.paint()
event.end |