Automatically detect and set resolution a game requests

The default in GLupen is 320x240, but e.g. Perfect Dark won't start unless you set 640x480 or above. Some games can change the resolution (and aspect ratio) in-game. I'd like to have an "automatic" option for the resolution that adjusts resolution and aspect ratio according to what the game requests. Increasing the internal resolution would be to change a multiplier in the options menu, just how Dolphin and mednafen-psx do it. Dolphin also has done the work to detect the precise aspect ratio and compensate if necessary: https://dolphin-emu.org/blog/2015/08/01/dolphin-progress-report-july-2015/#40-7133-automatically-detect-gamecube-aspect-ratios-by-phire. Maybe it can be appropriated for use in N64 games.

The issue names no source files, tests, or entry points, so begin by locating the emulator's resolution and aspect-ratio handling. Done would mean an automatic resolution option that responds to game requests while retaining a separate internal-resolution multiplier and correctly handling requested aspect ratios.