HWSW interview with Chris Donahue, DR Manager of NVIDIA

After posting my controversial editorial 'T&L: Revolution or Dead End', many an email I have received from readers. The majority kindly recommended that I should give up my humble attempts at writing about such matters, whereas some argued either in favor or against my position. Regardless of the diversity of opinion expressed in these messages, it became clear for me that my piece reached its purpose: it did stir up some strong feelings. Also the number of emails in itself was a clear indication that quite a lot of people are more than interested in this topic.

T&L in action: X-Isle from Crytek Studios

Therefore I thought it fit to ask for some clarification from those that are most competent in this matter: that is NVIDIA. This time Chris Donahue, Developer Relations Manager at NVIDIA Corporation was so kind as to devote some time to my questions:

[oldal:Q&A 1-3]

HWSW: As it was emphasized upon the announcement of the world's first GPU, the primary function of an on-chip hardware T&L unit is to off-load several demanding tasks from the CPU and provide software developers with the opportunity to create stunning visual effects never seen before on PCs. What it is exactly that this surplus of computing power that emerges as a result can be utilized for?

Chris: Developers can use the additional CPU cycles for additional things such as more complex A.I. and more realistic physics. I have yet to talk to one game developer that doesn't want more CPU time. This is why increasingly complex games run so well on NVIDIA GPUs.

HWSW: How do you see the relation between hardware T&L and such special instruction sets as SSE or 3DNow!? Recently Alf Covey of 3dfx has told me in an interview that these solutions exclude each other. Can you subscribe to this view?

Chris: The relationship is symbiotic- if we optimize the data paths to get the data to the GPU faster then it stands to reason that the entire application will benefit. There is nothing exclusionary and these are complimentary.

HWSW: What does SSE and 3DNow! driver optimization mean in the case of the GeForce series?

Chris: Actually, AMD and Intel have helped us with SSE and 3Dnow! optimizations, and we have seen a performance improvement in almost all situations. Again, this benefits the entire system, if we can get data processed and displayed faster then it's a win-win situation for the NVIDIA, the CPU manufacturer and the enduser.

[oldal:Q&A 4-6.33]

HWSW: Your amazing T&L technology demos push the envelope of what this unit can offer. But while these demos really show us that T&L is almost independent of the computing power of the CPU it is coupled with, they also indicate the limits of the given graphics chip. For example, if you happen to turn on FSAA you will have to observe that framerate may well drop below the 30 fps limit, which is the minimum requirement for a first person shooter game. That is, is it possible that a game utilizing all the features offered by T&L (just like these demos do) can be enjoyed at playable framerates?

Chris: Absolutely, if you look at some of the reviews done recently using the Detonator 3 drivers it's clear that you can turn on all of the features.

HWSW: Can we expect several titles to appear with T&L support in the foreseeable future?

Chris: Heck yes, there are already quite a few titles that use the T&L pipeline available and there will be a bunch more that exploit the T&L capabilites (see http://www.nvidia.com/products.nsf/xformlight_titles.html for the current list.)

HWSW: Given the aggressive 6-month product cycle in the graphics market, do we have to worry about the fact that by the time these titles will be released our, say, original GeForce card will have become far too obsolete to handle them?

Chris: No, one of the biggest challenges developers face is making a game scaleable enough to work on a wide variety of hardware - many games are still shipping with software rasterizers. Most of the people we work with are able to reward the people that have a high end system with a GeForce2 class GPU with higher res models, textures or more complex and detailed environments and characters.

HWSW: And here comes my inevitable 1/3 question: do we have to be afraid of NVIDIA PR?:)

Chris: Well, I can't really speak for Nvidia PR - I'm the manager of Developer Relations (but between you and I, when Diane wants something I don't hesitate, she has some REAL strong arms!)

Thank you.