Mouse help

I know how to use the mouse (the setup and recieving data) using interupt 33. However, you can only get the absolute position of the mouse (like x=0-319, y=0-199). I need to get how far the mouse has moved since the last update (delta x and delta y). Do you know how to do this?

PS: The program is made for mode 13, if it matters. Check my signature for the compiler

> Do you know how to do this?
Just remember the previous position

delta = current - previous
previous = current

Simple...

If the mouse is at the edge of the screen (ie 319), and moves it right, it will be 319-319=0. zero movement when the user moves the mouse to the right... not good.

I'm sure you can do this by calling the right interupt, I've done this before, but lost the code . Isn't this how mice works? They only send the data how far it has moved relative to the last time. It's up to the mouse handler to calculate where on the screen the mouse pointer is.

There must be a way to do this. Take Quake for example, where you rotate the view depending on how much you have moved the mouse, NOT where the mouse is on the screen...

Someone?