RetroArch

Installation

You can install RetroArch from the Alpine repo:

$ sudo apk add retroarch

Touchscreen

To enable touchscreen on RetroArch menu the following settings must be set in retroarch.cfg:

menu_mouse_enable = "false"
menu_pointer_enable = "true"

In case you're on a scaled display, you have to specify the scale factor in retroarch.cfg:

input_touch_scale = "2"

As of writing, input_touch_scale is only available in postmarketOS edge.

Cores

WARNING: Launching roms from RetroArch frontend doesn't always works as expected, for this reason it is recommended to launch games from command-line

These are the tested cores so far, if you manage to successfully test a core please add it to the list so everyone can have an idea of what can be potentially executed.

A list of installable cores can be found here: https://pkgs.alpinelinux.org/packages?name=libretro*&branch=edge

Overlay assets and configurations can be found here: https://github.com/libretro/common-overlays Shader assets can be found here: https://github.com/libretro/common-shaders

You can git clone them directly to your ~/.config/retroarch/overlay and ~/.config/retroarch/shaders folders directly.

Sega Master System

Genesis Plus GX
Installation	`sudo apk add libretro-genesis-plus-gx`
Retroarch overlay	`~/.config/retroarch/overlay/gamepads/genesis/genesis.cfg`
Shader	`~/.config/retroarch/shaders/shaders_glsl/crt/crt-easymode.glslp`
Command-line
`retroarch --set-shader "shaders_glsl/crt/crt-easymode.glslp" -L /usr/lib/libretro/genesis_plus_gx_libretro.so -c ~/.config/retroarch/retroarch.cfg --appendconfig custom.cfg YOUR_ROM`
custom.cfg
input_overlay = "~/.config/retroarch/overlay/gamepads/genesis/genesis.cfg" # Custom aspect ratio and game viewport size/position params aspect_ratio_index = "23" custom_viewport_width = "720" custom_viewport_height = "578" custom_viewport_x = "0" custom_viewport_y = "0"

Gameboy

Gambatte
Installation	`sudo apk add libretro-gambatte`
Retroarch overlay	`~/.config/retroarch/overlay/gamepads/genesis/genesis.cfg`
Custom overlay	ZilogZ92 custom overlays
Shader	`~/.config/retroarch/shaders/shaders_glsl/handheld/gameboy.glslp`
Command-line
`retroarch --set-shader "shaders_glsl/handheld/gameboy.glslp" -L /usr/lib/libretro/gambatte_libretro.so -c ~/.config/retroarch/retroarch.cfg --appendconfig custom.cfg YOUR_ROM`
custom.cfg
# ZilogZ92 Gameboy overlay input_overlay = "./overlay/gb_big.cfg" # Custom aspect ratio and game viewport size/position params aspect_ratio_index = "23" custom_viewport_width = "720" custom_viewport_height = "578" custom_viewport_x = "0" custom_viewport_y = "0"

PlayStation

PSCX Rearmed
Installation	`sudo apk add libretro-pcsx-rearmed`
Retroarch overlay	`~/.config/retroarch/overlay/gamepads/psx/psx.cfg`
Command-line
`retroarch -L /usr/lib/libretro/pcsx_rearmed_libretro.so -c ~/.config/retroarch/retroarch.cfg --appendconfig custom.cfg YOUR_ROM`
custom.cfg
input_overlay = "~/.config/retroarch/overlay/gamepads/psx/psx.cfg
Comments	Please follow PSCX Rearmed instructions, this emulator may need PSX bin files. Buggy on paella, low FPS.

Troubleshooting

RetroArch is highly configurable and allows some tweaks to increase performance. Please, if you find some share them here.

Buggy audio

By default RetroArch set audio driver to ALSA. This may result in buggy audio. I had to change it to pulse to have a smooth audio:

audio_driver = "pulse"

If this doesn't solve the audio issue it may be that the device is not powerful enought to emulate the game/platform under some conditions (overlays, shaders). Enabling video threading can be a possible solution:

video_threaded = "true"

`ok`	`←`
`down`	`√`
`up`	`×` (Multiplication sign)
`left`	`π`
`right`	`τ`
`toggle fullsceen`	`F7`
`exit`	`0`