OpenJKDF2 is an open-source re-implementation of “Jedi Knight: Dark Forces II” (JKDF2). OpenJKDF2 removes the hassle of rendering and input compatibility shims, while also providing in-app guided installation steps, cross-platform multiplayer, and a host of graphical (and other) improvements:

Jedi Knight™ Dark Forces II is Copyright © Lucasfilm Ltd. 1997-2009. An original “Jedi Knight: Dark Forces II” game disk, or original licensed assets from Steam or GOG, are required in order to play OpenJKDF2.