Carmack on multi-threading in id Tech 5

Written by Tim Smalley

August 22, 2008 // 12:27 a.m.

Tags: #5 #carmack #id #idf-fall-2008 #intel #james #john #keynote #megatexture #multi-threading #rage #renee #software #tech #threads

Along with the joint InTru 3D announcement with DreamWorks, one of the big focuses for Intel software chief Renee James’ keynote was future developer support for multi- and many-core products that Intel will deliver to market soon.

James invited John Carmack onto stage to talk about visual computing and he bought along what looked to be the same id Tech 5 Rage demo he showed at Apple’s Worldwide Developers Conference a while back.

While the demo was playing, Carmack spent some time talking about multi-threaded aspects of id Tech 5, where the entire rendering system is offloaded onto one core. he said this was a “natural progression” from the multi-core support it had included in previous generation titles. “That balances pretty nicely for most games, where you can run your game logic and simulation in one thread, and your rendering system in another thread,” he explained.

He explained that there was much more than just this going on in id Tech 5 though. He said that there’s a separate thread devoted entirely to “running analysis over what’s being rendered, managing the streaming of information from DVDs and hard drives, decompressing all of it, transcoding the formats that are useful for GPUs, and so on.

That sucks up a pretty good amount of processing power just to do that, but that's one of the key things that lets us do this level of detail that really is beyond anything that you've seen before,” he added.

Carmack on multi-threading in id Tech 5 Carmack on multi-threading in id Tech 5 Carmack on multi-threading in id Tech 5
Click to enlarge

We also have additional threads running. The high-level AI determinations that go on in the game logic runs asynchronously with the sort of tick-based stuff that handles the moving and bouncing into things on the game logic. Collision detection is also pulled off into a more fine-grain system that can handle offline contingent stuff going on separate from the main game frames analysis.

It’s the first time I’ve seen it on a big screen and I have to say was impressed – the graphics look crisp, with notable mentions going to the lighting and particle effects in particular. Carmack didn’t give a release timeframe for Rage, so I guess we’ll have to wait for further announcements from id Software.

Are you looking forward to Rage? Tell us in the forums.

WEEK IN REVIEW

TOP STORIES

SUGGESTED FOR YOU