I have a layout for my game similar to this:
Where the light gray area is reserved for HUD elements and the dark gray area is reserved for the actual game. One function I want to offer in the dark gray area is the ability to zoom and move around, which works independently from the light gray area, meaning that no matter how far I zoom in/out or how far I move, the light gray area remains unaffected.
How can I do this without always taking the offset center into account? How can I completely separate the game play part and the HUD?