[Feature Request] Support for rom hacks utilizing the power of "NES-on-a-chip" Famiclones

[Gagert]

I just recently stumbled upon a Super Mario Bros 1 rom hack named Super Mario Bros. 1 & 3 Mashed Together, which according to a forum thread I created on the libretro forums might use features from VTxx extended famiclones.

It would be neat to have those capabilities in this libretro core, because as of now it seems like only a modified version of fceux (found in the forum thread of this hack which is also linked in the YouTube video) and a custom build of Mednafen support this rom hack as of today (as far as I know).

[Gagert]

There seems to now be a fork of this core that has the ability to play this rom hack, I havent tested it yet though.

fceumm mod libretro

[negativeExponent]

not the same same. fceumm-mod emulates the VTxx(cant confirm this was working though as there are different vtxx floating around in different forms).
this is a game hack which requires its own hacked emulator. it might be based on the extended nes hardware feature concept by VTxx but its not VT.

EDIT:
ok nevermind. look like the repo has updated to support it.
with that note, why not just compile it and replace the core and run the game.

[Gagert]

I have the setup to compile this to a libretro core dll file, so I'm good (I'm using Windows 10).

It might be a bit of a hassle for a casual user to do this however if he/she would like to play rom hacks such as this specific Mario 1 rom hack.

[negativeExponent]

since its basically a "game hack" and since its already a libretro core, it might be better and safer to just move that repo over here or just create a buildbot for it to play such game hacks (renaming the core if necessary). the massive, non-real hardware feature could break support for some older systems the already supports.
but im just a contributor, with no voice power with regards to suggestions or ideas whatsoever so im just voicing out as usual expecting noone to hear it. Maybe someone will port over these changes here or whatever.

[Gagert]

Yeah, sounds reasonable.

I think I'll just keep this Issue open for now, just in case. The authors of this core can feel free to close this Issue if they want, as we now got a custom modified core for this custom rom hack.

[Gagert]

I successfully managed to build a libretro core from the modified fceumm build that supports this rom hack. I posted the compiled Windows 10 64 bit libretro core on the Discord server for this rom hack, for those who would like to try this rom hack using RetroArch without having to compile the core themselves.

The Super Mario Bros. 1 & 3 Mashed Together rom hack seems to be working fine in RetroArch, I recently had a playsession and didn't encounter any issues. 2 player mode also worked fine in RetroArch.

[NRS-NewRisingSun]

The FCEU-something builds with "VT03 graphics", including libretro-fceumm-mod, do not emulate VT03 graphics. They just emulate some fantasy console with enhanced capabilities that the author foolishly called "VT03 graphics", even as they have nothing in common with an actual VT03 hardware-wise. This incorrect description causes great confusion.

[saulfabregwiivc]

Anyone is still interested in adding this mod as another core for the next release of RA-Wii?
https://github.com/Tippek/libretro-fceumm-mod

It recently in 2021 has fixed for support the v1.1 version of the romhack "Super Mario Bros. 1/3" by Corpse Grinder.

I couldn't compile it myself.
Anyone can provide a compiled version?