Mouse Movement Code

I have been working on this mouse movement code that detects which direction the mouse moves in hope to use it in a game. The only problem is that I can not figure out how to make it move to the other side of the screen so I could continue turning to the right or left without having to stop. How would I actually get the x and y coordinants of the mouse to change?

PHP Code: if(x == xscreen){
//set x to 0
}else if(x == 0){
//set x to xscreen
}else if(y == yscreen){
//set y to 0
}else if(y == 0){
//set y to yscreen
} mh_sh_highlight_all('php');