Also, for what game uses which resolution: most 3d games use 352 or 704, most Capcom games use 352 (it is closer to the arcade CPS2 resolution), most SNK games use 320 (closer to the arcade Neogeo resolution). For other 2d games it is a toss-up – they can use either.
That’s something we’ll have to figure out through testing.
From what I’ve seen so far, most games fall into either 352/320p and 704i territory, even if there are quirks which I assume depend on very specific assets:
– Dead or Alive uses the same numbers as Virtua Fighter 2, as in, 352p for character select/loading screens, and 704i in game. Everything is pixel-perfectly centered. That said, the title screen – in spite of not looking off or stretched in 704i – has two small columns of white background cut off, left and right, leading me to believe it might use some oddball resolution, just for that one instance.
– Sengoku Blade, while is running flawlessly in 320p for the main game, comes with a special CD which is basically a glorified art gallery, all displayed in high resolution. Once again, the 704i profile provides a perfectly clean image, with the correct aspect ratio, yet there are tiny black bars at both sides, this time.
Now, there’s one beast I’m having trouble figuring out: Winter Heat.
704i seems perfectly fine for the hi-res assets used in the game, but according to SEGA Retro, the actual gameplay runs at a 704×240 progressive resolution I can’t find the optimal timings for. By logic, I tried the same values suggested for 704i, and they actually seem to work. Only problem is, the frame is completely off-centered, and there’s no way I can rectify that with H-backporch. Any clues?