Transparent Background?

Hello everyone! I am creating a game and am wondering if i could make it a transparent background? If any of you have heard of screen snake this is what i am asking for. I have all the code to make it transparent but don’t know where to put it. This game is for mac only so please don’t tell me it isn’t possible for windows. Does this only work w/ Objective-C Or can it work w/ Unity too?

Thanks!

Sam

EDIT: What i mean By transparent background is that you will see the desktop as the background.

As the GUI would be drawn over anything 3D, which isn’t very backgroundy, you’ll have to draw something 3d on a different camera on depth-only with proper culling mask and a different depth (higher or lower, i always mix them up).