RetroArch

Installing and configuring RetroArch in Ubuntu 24.04 LTS, running on a Lenovo X220.

Fresh install of Ubuntu comes with RetroArch, but I couldn't find the cores. There may have been easy fix (Settings > User Interface > Menu Item Visibility > Show 'Core Downloader') but I've already changed too much, and I don't feel like doing another fresh install to try. 

Snap package could not play in-game audio, possibly because of sand-boxing. Do not bother with snap package.

Installed the PPA from github:

sudo add-apt-repository ppa:libretro/stable && sudo apt-get update && sudo apt-get install retroarch

Had to modify the config (vi ~/.config/retroarch.cfg) so that

libretro_directory = "~/.config/retroarch/cores"

libretro_info_path = "~/.config/retroarch/cores/info"

And create the info directory (the cores directory already existed)

Start (or restart) RetroArch. Now Main > Online Updater > Core Downloader should be visible, but don't click it yet. First choose

• Update Core Info Files
• Update Controller Profiles
• Update Cheats
• Update Databases
• Update Overlays
• Update GLSL Shaders

Do one at a time, don't rush.

Then choose Core Downloader and you should be able to find e.g. mGBA, melonDS DS, and so on in the list.

Transfer ROMs over to e.g. ~/roms/gba and ~/roms/nds directories, using scp for example.

Then scan for them: "+" symbol > Scan Directory > roms/gba or roms/nds or even just roms.

If everything was setup correctly, the main menu bar should have a GBA icon or an NDS icon. If not, check the cores can be loaded. 

FWIW, "pulse" was the default sound driver, there was stuttering in Mario Kart: Super Circuit (GBA). The "alsa" driver should be better (it was).

RetroArch controls

• F1 quits the game 
• Pressing ESC twice quits RetroArch
• Navigating the menu using the keyboard: Backspace goes up a level, arrow keys up and down menu, ENTER to dive into a menu item.

Things I tried that didn't work

• The Lakka distro wraps RetroArch in LibreElec. Nice, but could not get the x220 to display externally, and sound buttons did not change sound volume.