OpenGL error in current version of LR-ScummVM

WeeFlats

Pi 3B, RetroPie v4.8.8, official PSU

Hi, I stupidly updated LR-ScummVM even though this core has caused me so many problems in the past, and now when I try to launch anything I get this OpenGL error:
[libretro ERROR!] Couldn't initialize OpenGL!

Every other core still works absolutely fine.

I can't even get the romdir-launcher to load to see any settings within the GUI, and manually editing scummvm.ini to try to change the video mode hasn't helped either.

So I wondered if there is a way around the error, or a way to revert to a previous version of the core.

Looking at "/home/pi/RetroPie-Setup/scriptmodules/libretrocores/lr-scummvm.sh" the only mention of OpenGL is here:

function build_lr-scummvm() {
    local gl_platform=OPENGL
    isPlatform "gles" && gl_platform=OPENGLES2
    cd backends/platform/libretro
    make clean
    make USE_MT32EMU=1 FORCE_${gl_platform}=1
    make datafiles
    md_ret_require="$md_build/backends/platform/libretro/scummvm_libretro.so"
}

Is there anything I could change here to force another GL version, or another video mode when installing from source?

Or could anyone explain how to install an older version? I just can't figure it out at all.

Even if anyone could give me the files from an older working version of "/opt/retropie/libretrocores/lr-scummvm/" I'd really apprecaite it.

If nothing can be done I can just use regular ScummVM, but I like to use a joypad to play these sometimes, and the controller support in the non-LR version is not very good.

Thanks a lot.

mitu

Looks like an issue with the core, caused by the recent addition of the OpenGL context support. I'll see what can be done for 3B devices, which support OpenGLES2 only with the current RetroPie release. Is the standalone ScummVM working fine with the same game(s) ?

WeeFlats

@mitu Hi, thanks a lot for looking into this, any help you could give me will be much appreciated. And yes, standalone ScummVM is working fine with the same games, i just really prefer the LR version.

mitu

For now, let's see what the upstream project thinks about the error and then we'll see how we tackle the problem.

EDIT: as a workaround, open the RetroArch core options file (/opt/retropie/configs/all/retroarch-core-options.cfg) and add:

scummvm_video_hw_acceleration = "disabled"

to disable any OpenGL initialization. The core should work as before.

WeeFlats

Amazing, it works!

Thank you so much. I only tried Monkey Island 1 so far, will check another couple of games as well.

I hope an actual fix comes to help other people in my situation but in the meantime this is great.

WeeFlats

Just checked some more demanding things like Monkey 3 and they run very slowly, so I guess that's what the acceleration helps with!

But for now it's still a great temporary fix.

WeeFlats

Sorry to keep replying to my own post, but I was just wondering if there's a way I can revert to the prevous version of this core via the method described here:
https://retropie.org.uk/forum/topic/27421/is-there-any-way-to-get-older-emulator-core-binaries/7

How would I determine the version number needed to install the previous version?

WeeFlats

@mitu Just wondering if there is any plan for a proper solution for this as I am almost finished my build and all that's outstanding is this LR-ScummVM issue.

If I have to make do with regular ScummVM I suppose that's OK, it's just that the LR version is so much better. Thanks for your help, regardless.

Lolonois

@WeeFlats I guess you have to be patient. A Rpi3 should support OpenGL ES 2.0 but for some reason the implementation in this libretro core is not working.

For me, the most important things can also be done in the native ScummVM: Soundfonts and Shaders, thus there is not that much need to use the lr core, unless for uniform configuration of RA/lr.

WeeFlats

@Lolonois @mitu is it now safe to upgrade to the latest version on a pi 3?

https://github.com/RetroPie/RetroPie-Setup/commit/191631b0d870d05bb679d39d62861d210d919ea3

Thank you again for everything.

mitu

@WeeFlats Sure, update Retropie and the included packages and then try the ScummVM core again.