Sorry, this is probably a really newbie question, but I'm now moving into Cocoa (after almost 2 years in Real Basic) and I've got a simple sidescroller in the works, I have the key input working fine, but I can't find how I get the mouse X and Y (in RB i just had to check system.mouseX/system.mouseY), i would prefer if it was window-relative (so you could choose to play the game in a windowed mode), but screen relative would be fine too (then you'll be forced to play it full screen).

Thanks for any help,
Phate

Look around in NSEvent for getMouseLoctionInWindow. The number of times this (and questions about setting the mouse location) have been asked definitely warrant an FAQ entry.

i usually do somthing (from an NSView) like :

[NSEvent mouseLocation].x-[[self window] frame].origin.x-[self frame].origin.x
and
[[self window] frame].size.height-([NSEvent mouseLocation].y-[[self window] frame].origin.y-[self frame].origin.y)

ededed, you might want to have a look at NSView's convertPoint:fromView: and convertPoint:toView:, as well as NSWindow's convertBaseToScreen: and convertScreenToBase:. Might help avoid all those subtractions...