Releasing the source code for Wolfenstein, Doom, Quake, Quake 2, Quake 3 was very much a Carmack thing. Source code releases for extremely successful, closed, c

Releasing the source code for Wolfenstein, Doom, Quake, Quake 2, Quake 3 was very much a Carmack thing. Source code releases for extremely successful, closed, commercial projects remains very uncommon (though it is fair to point out that the current Unreal Engine code is published.)