How would one find the size of the viewing rectangle(X/Y coords in the camera's local system) at a certain distance ahead of the camera. I know it's based off the cameras zoom/aspect ratio, but I don't want to just understand a the blitz method of doing so, as I don't know if it's essentially the same when directly using DX, and oGL, or if it differes alot.
Any help is appreciated.
Any help is appreciated.