Hup

You will need to have two different types of resolutions: client resolution and a virtual resolution. The client resolution is responsible for changing the resolution of the client window by assigning its width and height and determining if the client is full screen or not. The virtual resolution is responsible for how your game content is drawn inside of the game client. Therefore, you could set your client resolution to 800x600 and still be able to draw content that is 1920x1080 or whatever your graphics are set for. If you would like assistance with implementing something like this then let me know.