Unveiled as a surprise guest at Apple CEO Steve Jobs's WWDC07 keynote, id co-founder and technical director John Carmack gave the audience the first look at 'Tech 5,' its new engine for Mac, PC, PS3, and Xbox 360. Consumer electronics site Engadget noted the appearance in its live coverage of the Worldwide Developers Conference 2007 keynote from San Francisco's Moscone Center. "So the last couple of years at id we've been working in secrecy on next-gen tech and a game for it," Carmack is quoted as saying, as the demo showed a logo naming the engine "id Tech 5." Though details of the engine are currently still scarce, Carmack revealed a number of real-time user-editable features in the engine, saying, "What we've got here is the entire world with unique textures, 20GB of textures covering this track. They can go in and look at the world and, say, change the color of the mountaintop, or carve their name into the rock. They can change as much as they want on surfaces with no impact on the game." More announcements on the engine are expected to be revealed at E3, with Carmack telling the audience the engine was geared toward PC, PS3, Xbox 360, and, of course, Mac -- a platform heretofore often relatively ignored by bigger industry publishers. Carmack said "another Mac announcement" would be made at this year's E3, as well. (photo credit: Engadget)