I'm working on a "2.5D" game where everything is still proper 3D but everything lives at 0 depth. Think of any standard side-scroller, Geometry Wars, or so on.
If I know I'm running at 1024x768 (just for example) resolution and I know that my "world" is constrained to x {-1.0, 1.0} and y {-1.0, 1.0) how do I go about creating my perspective and transform matrices other than trial and error?
I probably have to pick a camera depth, and because I do not want a lot of distortion, let's say z=1000 for the camera. But how do I go about getting my matrices so that the 1024x768 pixels I have map to a 4:3 region of game world?
Since the screen space in a side-scroller may be 1/20th or so of the actual 2D world, the camera will have to move horizontally as well. And similarly, I need to know when to start and stop the camera so that you do not run off either end.
As I said, I could probably guess and fine-tune until I got it right, but I have to imagine there's a more rigorous way to go about it.
Thanks for any tips!
Dave
PS: I'm not even entirely sure I'll need a projection matrix, but I would like to be able to zoom in and out.
