RetroArch Alt is an alternative Front-End interface to RetroArch...
It's for people who don't like the standard interface of RetroArch and want something that is easier to navigate. (read on if that really didn't make any sense whatsoever).
RetroArch Alt is an alternative frontend user interface to the program RetroArch (which you will also need). ('RetroArch Alt' uses RetroArch to do anything meaningful). The RetroArch emulator is a separate program entirely which allows you to emulate many games systems, which have come and gone over the years. Anything from ZX Spectrum, Atari, Commodore 64 etc to Playstation, Gamecube and even Arcade games. Before I get into anything else, there's no ROMS on this site (ROMS are the actual games you'd play with the emulator.) They are the equivalent of the cartridge or game disc the original games machine would have needed to play.
Distributing them is mostly illegal, so again you won't find them here.
You can freely download the cores (mac versions) /(linux versions) though. The cores are plugins which are used by RetroArch to emulate a specific system. The great thing about this is any improvements to RetroArch compatibility can be upgraded simply by swapping out an updated core file.
BIOS files are sometimes required for greater compatibility. Again, the same situation as with the ROMS; you won't find them here due to copyright issues, although it's possible to play many systems without the BIOS files being present.
Lastly (and this will probably only make sense when you come to use the program), RetroArch Alt will pick the relevant emulation core for you based on the ROM it thinks you are opening. You can modify which core is used manually with the drop-down lists, or you can edit the file 'matching_rules.txt' to have RetroArch Alt always pick a specific core for you.
Me using RetroArch Alt to play Shadow Dancer (Megadrive).
One change I would advocate making (when you first launch RetroArch), is run RetroArch, then go across to Settings > Driver > Menu Driver > [choose rgui]. Now press your right-hand mouse button to navigate backwards until you are at the Main menu again then Configurations > Save Current Configuration. This will actually make RetroArch useable when you configure the keyboard or joypad. Close RetroArch (escape key) and run RetroArch again to see the change.
RetroArch Alt is free.
version 1.0 - December 2018: Initial release
version 1.1 - January 2019: A few small tweaks to the interface
March 2019: Hooray - a Linux version!
version 1.2 - May 2019: code cleanup and interface tweaksversion 1.30 - Aug 2019: A few fixes to the way ROMS are listed in menus, and theme overide fix for Linux
This means RetroArch Alt should be much more compatible and allow more games to run properly (regardless if they are '.d64', 't64' or '.prg' files).
version 1.32 - Apr 2020: Playstation 1 and Playstation 2 menu fix, appearance theme applied.
version 1.33 - Jan 2021: A bit of code cleanup with custom appearance themes support. Also added the ability to navigate the menus and thereby run a game from the keyboard / joypad buttons. 'A' key selects the ROM, 'D' key selects the core, and the 'S' key presses the run button. I mapped it to these as W,A,S and D keys are most commonly used in game movement.
version 1.34 - October 2021: Fixed the sort order of the drop-down menus. They should now behave the same under all operating systems.
Note: The Linux version of RetroArch-alt also enables you to select an Appimage as an alternative option.
Tested with Mac OS X 10.7 up to MacOS 10.14 Mojave.
Linux version Tested with Ubuntu 19+, and Debian 64bit intel.
If you have any suggestions, please get in touch via email. Many thanks.