Creative Is Blocking Carmack From Releasing Doom 3 Source Code

John Carmack has pledged to release the source code of Doom 3 as soon as Rage was released but he hasn't fulfill that pledge yet, and the reason behind that turned out to legal and patent issues.

A key algorithm in the id Tech 4 graphics engine which powers Doom 3 is called "Carmack's reverse." This algorithm is a clever implementation of shadow volumes using the stencil buffer found in the GPU. Carmack developed that algorithm independently in 2000 before discovering that Creative Labs has filed a patent for a "Method for rendering shadows using a shadow volume and a stencil buffer" in 1999.

The USPTO granted the patent to Creative in 2002, so Carmack negotiated with them a deal to use the algorithm in exchange for supporting Creative's EAX technology and to display their logos in the game. Problem is, this deal doesn't extend to third party games that'll be created using the source code once it is freed.

To get past this hindrance, Carmack is now writing replacement code for the patented parts of the engine. Hopefully, the new code will be on par with the original code in terms of visual quality and performance.

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I don't trust anything from ID it lost it's flare somewhere between Quake 1 and Quake 2 doubt any of it has to do with patents, think of Homeworld 1 in the case of released source code.


See "Prey". Not everyone's cup of tea, but a nicely done game with some impressive set pieces. id has always made really good engines for others, such as Raven in the past, to run with and give us not games, but experiences!

Its funny how stupid this

Its funny how stupid this sounds, like think of it, legal issues because of a "stencil buffer", i mean, what the hell is wrong with people, who gives a flying crap. Creative is soo dumb. The judge would be like, daaawww whadafuuuh, no more buffering of the stenicls, now where's my tomato juice!?


Doom 3 was the first game to use vertex shaders too. Might explain why it was one of the most atmospheric and graphically impressive games of it's time. Sure, there were a few that had similar characteristics of it's time, but Doom was in a league of it's own and stood out because of those technology's.

Why do they even bother

I mean. Haven't they come up with some new sort of shadowing tech by now? If so, why would they bother stopping Carmack if everyone now many years later uses something of their own or something better?

But that's how the world goes with the suits and patents. As soon as someone tries to do something good for the community/fans/anything, there will be someone somewhere to say "Hey, you can't do that or I will sue you."

Right of the bat

Still an impressive intense game for it's era. The second someone tries to do something good, there is always a bunch of asshole stopping them. The modding possibilities if the engine got released would be awesome.

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