Integer Scaling on Amiga Core

Something is off about the integer scaling with the Amiga core. Amiga PAL resolution is 320256/640512. This would mean that a 4x would make it almost fill it vertically in 1080p, considering the usual black borders amiga games have.

I fear retroarch is assuming some of the natural black borders as not being part of the game or image, and using integer scaling forces a tiny game window in the center of the screen. Comparing it to standalone FS-UAE or WinUAE with integer scaling proves that retroarch/p-uae is not scaling the games correctly.

First of all the Amiga has 288 vertical lines not 256, and Puae runs at high resolution by default. That means if you integer 2 times you have 576 and if you do it twice you have 1152 which is more than 1080 and retroarch by default won’t allow it. You would have to enable overscale.

PUAE assumes the total of the PAL signal, which is 288px, you need to use the core video options to crop the borders appropriately. Since the vast majority of Amiga games use only 200 lines even if coded for PAL, you need to crop beyond 256px though if you want to fill the screen the most (ie. 1000p).

No he shouldn’t crop because there are hundreds of games that use 256 pixels. He should just enable overscale on 1080p.

  1. Autozoom (crop) core option works very well in almost all cases, so no fear of cropping wanted stuff out of the screen.

  2. In order to use 1:1 aspect via frontend, the core must be set in either low res or high res + double lined, otherwise the aspect will be extremely off. “Core provided” handles it fine and also allows the use of core option cropping.


So, if I have “integer scaling” on on the general settings, using autozoom is absolutely fine? It doesn’t override?

Sure they can coexist, but the effect may not be desired.