Id Software co-founder and lead developer John Carmack
was invited onstage at last week’s Macworld Expo Tokyo keynote, where he demonstrated an early development of the engine Id is using to develop the next game in its legendary Doom first person shooter series.
Carmack’s demonstration highlighted the new effects capable by Nvidia Corp.’s latest graphics chip, the GeForce3, which was officially unveiled for the first time at last week’s Tokyo Expo. Nvidia says that Apple will be the first or one of the first companies to ship the GeForce3. The GeForce3 is now available as a build-to-order option on Power Mac G4s, expected to ship in March.
Carmack quickly returned from Japan to Id Software, where he updated his .plan file with more thoughts and observations on the GeForce3 and the future of 3D graphics technology. Carmack also
posted some observations about the comparative performance of Power Mac G4 systems and Pentium III-based systems to “News for Nerds” site Slashdot, noting that Apple’s 733MHz G4 isn’t as fast as a 1GHz Pentium in his own tests.
Carmack’s comments have incited debate among Mac users, including questions about the authenticity of Carmack’s Slashdot remarks. MacCentral confirmed with Carmack over the weekend that he did indeed post the comments.
“Yes, those are my comments,” said Carmack.
Carmack further clarified his position on the relative performance benefits of Macs and PCs.
“The position hasn’t changed in years — PPC CPUs are as good as, or slightly better than, x86 on a clock for clock basis, but they can’t overcome the large MHz gap that exists,” said Carmack. “Altivec has some wins, but it won’t make any significant difference unless the performance is extremely focused in a small area, and the balance of computation and bandwidth is just right.”
The GeForce3 in particular is being touted by Nvidia as offering infinite flexibility for developers who want total control over the way that geometry and pixel shading information is calculated. Nvidia also says that the chip’s new memory management architecture promises extraordinary performance potential, as well. Carmack says that such advances will make it harder for developers to take advantage of features like the G4’s Velocity Engine (or, as it’s known in Motorola parlance, Altivec).
“Now that 3D cards are doing all the rasterization and geometry work, the traditional hot spots in games are gone, resulting in a much more diffuse profile that is harder to spot optimize,” said Carmack.