What is iodoom3?
On November 22, 2011 id Software released the source code to Doom 3. This project aims to build upon that source code release by cleaning up, fixing bugs, and adding features. Our permant goal is to create the open-source Doom 3 distribution upon which people base their games and projects. We also seek to have the perfect version of the game engine for playing Doom 3, it’s expansion pack Resurrection of Evil, and all popular mods.
Who created this project?
The people that brought you ioquake3.
Will PunkBuster work with iodoom3?
Nope, PunkBuster is closed-source software and cannot be made to work with open-source software.
Does this mean that Doom 3 is free to play?
No. Playing Doom 3 still requires a legitimate copy of the game. You can purchase a copy from Steam or your favorite retailer.