Forcing internal resolution in MAME core?

Libretro Cores
#1

This is going to sound like a repeat of an earlier query I made with regard to how the vecx core handles graphics. This time, MAME. Having sort of the same issue: Native MAME defaults to displaying vector games (and its own Vectrex emulation) at whatever resolution my display happens to be, whereas RetroArch seems to want to render the graphics internally at a lower resolution and scale that up.

The chosen internal resolution is hard to pin down but seems to be perhaps 640x480. Although there is a bevy of options in the Retroarch.cfg for specifying resolution, none of them have an impact. I have tried: video_fullscreen_x/y, video_window_x/y, custom_viewport_width/height, setting each to 1920x1080. The only thing any of that accomplishes is to stretch the image to the full dimensions of the display, along with the artifacts of the low-resolution render.

It is unknown whether the fact that the “resolution” setting in RetroArch’s F1 menu caps at 960x720 has any bearing on this phenomenon.

Outside of generating thousands of .bat files, I don’t have the luxury of choosing to use native MAME.EXE for vector games and RetroArch for everything else, so I need to find a way to sort this out.

#2

With the alternate render option enabled, the resolution option should increase the core’s internal resolution. We could add more resolutions to it, which has been discussed already in this issue:

1 Like
#3

Alright, alt render permitted higher resolutions, but as you say, it seems 960x720 is a fundamental limit at this time. Thanks for the info.

#4

I tried adding more. We’ll see how that works.

1 Like
#5

do those resolutions affect the aspect ratio?

#6

There’s a check for 4/3 and all old ones were 4/3 or 16/9, so I added the same kind only.

1 Like
#7

I tried adding more. We’ll see how that works. https://github.com/libretro/mame/pull/39/files

I am not knowledgeable enough to make immediate use of this change. Are there any how-to instructions? This turns out to be important because I have recently discovered to my dismay that the limitation of 960x720 is detrimental to more than just vector graphics. It’s a problem for any game at all that uses artwork, because generally speaking that artwork comes in 1080p+ flavors. When it gets arbitrarily scaled to 720p and then back to 1080p, that needlessly degrades the quality.

1 Like
#8

New resolutions have been added for the alt renderer. It should be on the buildbot/updater.

1 Like
#9

great! can you add this to the the mame2014 and mame2016 Cores too ?

#10

lol always asking more more and more…

BTW in older implementation , I had only done thing simple like use altres? then use the max res (1600x1200): else use game res. So it’s not just a quick commit like just add some new res like 1920x1080…

That said it’s doable (i did it in current :slight_smile: ), just add new option for resolution to use in altres then use it if altres . For now I’m not on mame cores , so I let someone else doing a PR ,if none maybe I will do it later.

1 Like
#11

i really can’t stop trying and asking :slight_smile: maybe i can take a larger break if everything is running fine for me with the mame-cores :smiley:

#12

If the old ones are already using max res, what’s gained by adding the others? Won’t the artwork etc. still look good after downsampling from that higher res?

#13

Hi @hunterk , in older implementation ,sizeof screen was limited to 1600x1200. It could be good to choose higher appropriate resolution . that said, in the past I never used the alt resolution .

recently I was working on the mame internal debugger using imgui ( I had to finish this one a day) and then I’ve appreciate the use of alt resolution.

#14

Ah, yeah, I bet that small imgui text really highlights any scaling issues :slight_smile: