"ioquake3 is a free and open-source software first person shooter engine based on the Quake 3: Arena and Quake 3: Team Arena source code. The source code is licensed under the GPL version 2, and was first released under that license by id software on August 20th, 2005. Since then, our dedicated team has working hard to improve it, fixing bugs, and adding just the right new features to make the engine even better than before."
What can you do with it ?
"You can use it to play Quake 3: Arena, Quake 3: Team Arena, and the mods people have made for those games. See our Player’s Guide for instructions and help playing ioquake3, or our SysAdmin Guide to get started running your own game server. Or play a game that other great teams using ioquake3 have made if you don’t already have Quake 3.
You can also make your own game from our source code in git on gibhub."
ioQuake3 - Code
The following are excerpts from their website.
What is ioquake3 ?
"ioquake3 is a free and open-source software first person shooter engine based on the Quake 3: Arena and Quake 3: Team Arena source code. The source code is licensed under the GPL version 2, and was first released under that license by id software on August 20th, 2005. Since then, our dedicated team has working hard to improve it, fixing bugs, and adding just the right new features to make the engine even better than before."
What can you do with it ?
"You can use it to play Quake 3: Arena, Quake 3: Team Arena, and the mods people have made for those games. See our Player’s Guide for instructions and help playing ioquake3, or our SysAdmin Guide to get started running your own game server. Or play a game that other great teams using ioquake3 have made if you don’t already have Quake 3. You can also make your own game from our source code in git on gibhub."