The Bethesda Blog announces the promised release of the source code for the DOOM 3 BFG Edition under terms of The GNU General Public License. The id Software section on GitHub has the files along with an explanation of the legalities of using the source code, and additional restrictions besides the GNU GPL, including this condition: "This source release does not contain any game data, the game data is still covered by the original EULA and must be obeyed as usual." The same update also has details on a new patch that will automatically be provided for the game through Steam. Here are the patch notes:

NEW FEATURES

• All projectiles cast shadows
• Texture LOD bias added to menu options
• Added option to force v-sync (instead of “smart v-sync”)
• Adjusted default brightness value
• Shadow casting projectiles added to menu options
• Allow setting anti-aliasing up to 16x on Nvidia hardware. AMD/Intel cap is at 8x
• Adjusted range of vertical sensitivity (allows you to lower sensitivity further than original implementation)
• Added option to disable checkpoints
• Allow left/right to enter resolution menu
• Variable FOV settings options were added into the main menu
• Added controller bind options
• Added additional anti-cheat measures

BUG FIXES

• Fixed blood splatter effects break after reloading save game
• Fixed broken view nodal code that allowed players to see through the world by backing into a wall and looking up
• Fixed weapon impact effects break after using the artifact (heart)
• Fixed leaderboards to work across languages