Fun with vectors.

To convert from the normal computer's co-ordinates system to cartesian co-ordinates, just add half the window width to the x co-ords, and half the window height to the y co-ords.

You may also wanna check out my game in thread :
http://forums.vb-world.net/showthrea...threadid=56233

You might get some ideas from it...

- jamie

Perfect. Thanks.

Oops, just realised a mistake - I meant "x increases to the right". Looks like you're sorted though, so no worries.