Page 1

A brief chat with ATI's Neal Robison

As you likely have noticed, last week we published a game review on The Elder Scrolls IV: Oblivion with a focus on graphics cards. Obviously most of you have heard about the "Chuck' patch which allows you to enable both HDR and antialiasing at the same time with ATI's Radeon X1000 family of graphics cards.

It's good marketing as up-to this point NVIDIA can not handle the two in this gaming title.

With that in mind I figured it would be nice to have an interview with ATI about this next to our Oblivion article. Unfortunately the interview got a little delayed, but none-the-less here it is. I do recommend you read our Oblivion article first, especially the page where we take a Crossfire rig into HDR+AA.

Neal Robison is the person being interviewed here, he's ATIs global Director for Developer Relations and despite his very busy schedule we have managed to get Neal to agree to Q&A session. We talk a little about the afore mentioned features, gaming in general, consoles, and as we are both in this industry .. the future of gaming.

First a quick course on HDR:

HDR is something you all know from games like Far Cry, extremely bright lighting that brings a really cool cinematic effect to gaming. This effect is becoming extraordinarily popular and the difference is obvious. HDR means High Dynamic Range. HDR facilitates the use of color values way beyond the normal range of the color palette in an effort to produce a more extreme form of lighting rendering. Typically this trick is used to contrast really dark scenery. Extreme sunlight, over-saturation or over exposure is a good example of what exactly is possible. The most simple way to describe it would be controlling the amount of light used present in a certain position in a 3D scene. HDR is already present in Far Cry, Oblivion, Age of Empires III, Half Life 2: Lost Coast, Serious Sam 2, 3DMark06 and will be available in Unreal 3 to name a few titles.

Look clearly at the overexposed lighting effects, that's HDR. It'll bring a nice cinematic effect to gaming. 

Guru3D: HDR is pretty much the latest hip thing for current and near future games. A lovely feature. Yet up-to the X1000 family it was impossible to render both HDR and antialiasing at the same time. You now have introduced great support for it in combination with a working anti-aliasing solution (AA). Last week ATI released a really nice hot fix in which it enabled the possibility of doing AA and HDR at the same time with ATI X1000 family graphics cards.

HDR & AA for NVIDIA obviously does not work for them as well as they have to run their HDR instructions though the Shader engine. It's a non-standard approach which I believe will limit NVIDIA's support for this really nice combo. Lately I have seen tremendous efforts from ATI to push both HDR and AA to be supported with games just because you can. Why and where is that dedication coming from all of the sudden ?

Neal:  Actually, as youve pointed out, the support for HDR + AA has been available since the introduction of the X1000 family of ATI video cards late last year.  We have been working with most of the industry-leading PC developers to include this feature in their games.  We have to work closely with these developers, because of the different release cycles for their games throughout the year.  You can see that HDR + AA has been implemented in several games already:  Far Cry, Serious Sam 2, Age of Empires 3, Half Life 2: Lost Coastjust to name a few.  So, I would say that the dedication to getting HDR + AA has been there for quite awhile.  I think that the Chuck patch to the ATI Catalyst driver, that enabled  HDR + AA for Oblivion has really shown the public what this kind of graphic feature can do to enhance a game.

Guru3D: When we look at AA+HDR enabled in games, what is it that gives ATI the edge over the competitors solution? How does NVIDIAs solution differ from ATIs and if it is, why is it superior?

Neal:  The shortest answer is that NVidia simply doesnt offer an HDR + AA solution.  ATI does.  I have to give tremendous credit to our GPU architects in championing this amazing feature a long time ago.  The combination of HDR and anti-aliasing can really enhance a game, and ATI provides that feature in an elegant, easy-to-implement way. If NVIDIA was to fake HDR + AA, I suppose they could but either the performance would be miserable, or the resulting graphic quality wouldnt be enough to actually improve a game.

* Hilbert - again, NVIDIA Series 6 & 7 cards can do HDR+AA, yet HDR is managed through shaders, not an optimal approach.

Guru3D: As stated in the first question, the latest hottest title supporting the combo was Oblivion and there were some rumors that the "patch" was done in less than 12 hours. Why is it so simple to implement on the X1000 family of graphics cards ?

Neal:  Thats a great question.  I can tell you that the patch to the ATI Catalyst driver took a little more than 12 hours but not much more.  Most of the time was spent in testing the solution not in the implementation.  The secret lays in the simple fact that HDR + AA was designed into the ATI video cards from the very start.  Its not some trickits not some brilliant hackits designed to be a part of a fantastic gaming experience.

Enabling HDR + AA in a game really is a simple process but only if a developer has gone through the process of integrating HDR into their graphics pipeline.  I appreciate the game developers that have taken the time to bring these types of rich graphics features to their consumers.  That way, integrating HDR and AA is easyand the pay-off for consumers is huge.

HDR + NO AA (click image to enlarge)	HDR + 4x AA HDR + NO AA (click image to enlarge)