parallel x WideScreen Mode (16:9) x Stretch Image

Something that in my opinion should be changed not only for this core but for everyone else present in RetroArch would be the appropriate correspondence between the option chosen for the type of video and the result that we see on the screen. I will explain improvement now.

The option:

• 4: 3:
  In older games it keeps the side edges.

• Stretch:
  When the person wants to eliminate the edges in the older games.

• And the 16: 9 mode:
  That it would be able to be chosen only if the game managed to work with a widescreen aspect ratio without stretching the image.

Currently we see the option 16: 9 to be chosen but routinely the emulator is not able to work with a real widescreen. Stretching in this way the image of the game. So the user sometimes chooses 16: 9 but what we actually see is not 16: 9, but just a stretched screen.
Abstract: The chosen option does not correspond effectively with the image reality that is delivered.
I think that way it would make it clear to the user whether the game allows the real widescreen or not.

No files, tests, or entry points are named. Start by locating the emulator's video aspect-ratio handling and compare the 4:3, Stretch, and 16:9 paths. Done means the 16:9 option clearly corresponds to genuine widescreen support rather than silently stretching older games.