Attract-Mode vs Onyx

Attract-Mode is a graphical frontend for command-line emulators such as MAME, MESS, and Nestopia. It is intended for arcade cabinets and control by joystick, gamepad, or spin dial, and runs on Windows, OS X, and Linux, including Raspberry Pi and Odroid. Users can import game lists, generate lists from emulator directories, and set launch commands for individual games. The frontend can retrieve missing game details and artwork from TheGamesDB, Progetto-Snaps, and adb.arcadeitalia.net. Controls can be assigned to joystick, keyboard, or mouse inputs, including combinations. A built-in configuration menu has on-screen help, and settings are stored in text files. Layouts can be scripted in Squirrel and customized with themes, animations, and GLSL shaders. It supports media formats supported by FFmpeg and SWF files through gameswf. The feature list also names Steam support and plug-ins for extensions or integration with external programs. Attract-Mode is free and open source under the GNU General Public License v3. Pause functionality for returning to the frontend and resuming an emulator is listed only for Linux and Windows versions.

Onyx has no write-up on Specifiction yet; its figures are above.