NVIDIA Doubts Ray Tracing Is the Future of Games

SizeWise writes "After Intel's prominent work in ray tracing in the both the desktop and mobile spaces, many gamers might be thinking that the move to ray-tracing engines is inevitable. NVIDIA's Chief Scientist, Dr. David Kirk, thinks otherwise as revealed in this interview on rasterization and ray tracing. Kirk counters many of Intel's claims of ray tracing's superiority, such as the inherent benefit to polygon complexity, while pointing out areas where ray-tracing engines would falter, such as basic antialiasing. The interview concludes with discussions on mixing the two rendering technologies and whether NVIDIA hardware can efficiently handle ray tracing calculations as well."

Comments

Counterpoint

[peipas]

Kirk should talk to Picard who is quite enthused about real time raytracing.

Re:Counterpoint

[moderatorrater]

That lends a lot of weight to the raytracing argument, since I generally prefer Picard over Kirk...

Re:Counterpoint

[peipas]

Yes, I loved the episode where Odo shape-shifted into a layer 3 switch during the Romulan invasion.

Re:Counterpoint

[Applekid]

We're not talking about the current technology, we're talking about the future. As in whether Ray Tracing is the Future of Games.

Graphics hardware has evolved into huge parallel general-purpose stream processors capable of obscene numbers of FLOPs per second... yet we're still clinging tenaciously to the old safety blanket of a mesh of tesselated triangles and projecting textures onto them.

And it makes sense: the industry is really, really good at pushing them around. Sort of how like internal combustion engines are pretty much the only game in town until alternative save themselves from the vapor.

Nvidia, either by being wise or shortsighted, is discounting ray-tracing. ATI is trailing right now so they'd probably do well to hedge their bets on the polar opposite of where Nvidia is going.

3D modelling starts out in abstractions anyway with deformations and curves and all sorts of things that are relatively easy to describe with pure mathematics. Converting it all to mesh approximations of what was sculpted was, and still is, pretty much just a hack to get things to run at acceptable real-time speeds.

Steve Jobs also uses this trick

[OrangeTide]

Saying something sucks if he's already developing a product for it.

Relief Texture Mapping

[DeKO]

A good way to mix both techniques is Relief Texture Mapping. It's a good way to get smooth surfaces thanks to the texture interpolation hardware, with no extra polygons.

Like we were expecting something else

[Btarlinian]

Seriously though, does anyone expect Nvidia to say, "Yes, we really do think that our products will all be obsolete and outdated in a few years. Thank you for asking." I personally have no idea as to whether or not ray tracing is the future of games, but I really don't think that Nvidia is the right person to ask either, (just as Intel isn't).

Re:Like we were expecting something else

[Abcd1234]

Actually, I don't think that's true at all. Raytracing, just like today's rasterizers, can greatly benefit from dedicated hardware for doing vector operations, geometry manipulation, and so forth. This is particularly true as raytracing benefits greatly from parallelization, and it would be far easier to build a dedicated card with a nice fat bus for shunting geometry and texture information between a large number of processing units than it would be to use a stock, general multicore processor which isn't really designed with those specific applications in mind.

Besides, the whole reason to have separate, specialized gear for doing things like audio/visual processing is to free up the main CPU for doing other things. Heck, we're even seeing specialized, third-party hardware for doing things like physics and AI calculations, not to mention accelerators for H.264 decoding, etc. As such, I see no reason to move graphics rendering back to the main CPU(s).

Hmmm - who to believe, who to believe??

[$RANDOMLUSER]

Intel says to do it with the CPU, and nVidia says to do it with the GPU. What a surprise.

Obey your thirst...

[Itninja]

Personally, I prefer spites to either ray-trace or polygons. I still thing Starcraft (the game, not the conversion van) had some of the best graphics. But then I am kind of a fuddy-duddy. I also think River Raid was an awesome game.

What do the people that make the software say?

[9mm Censor]

What about game and engine devs? Where do they see the future going?

Re:What do the people that make the software say?

[Squapper]

I am an game-developing 3d-artist, and our biggest problem right now is the lack of ability to render complex per-pixel shaders (particulary on the PS3). But this is only a short-term problem, and what would we do with the ability to create more complex shaders? Fake the appearance of the benefits of Ray-tracing (more complex scenes and more realistic surfaces) of course!

On the other hand, the film industry could be a good place to look for the future technology of computer games. And as it is right now, it's preferable to avoid the slowness of raytracing and fake the effects instead, even when making big blockbuster movies.

Probably right on this one...

[Bones3D_mac]

For the most part, I really don't see ray-tracing adding much to the world of gaming that isn't being handled well enough by current methods. Unless someone was specifically creating games that somehow directly incorporated either the benefits or the added calculations involved with ray-tracing itself, it would only be a costly, and highly inefficient gimmick of an alternative to current techniques.

Sure, ray-tracing has its place in a lot of areas, but real-time gaming would be a terrible misuse of processing horsepower... especially when you could be applying it to other areas of gaming that actually affect gameplay itself. For example, how about more robust AIs for in game elements, or high-end physics processing that can combine things like fabric/hair/ fluid/fire physics processing with the ability to decimate objects completely as vector-calculated chunks based on the surrounding environments, rather than all this predetermined destruction we currently see in games. (Example, a surface could be eroded incrimentally by having a fluid running acrossed it until a hole forms in the shape of the fluid path...)

Hardly anything new

[K. S. Kyosuke]

For years, the movie studios were using Pixar PRMan, which is in many ways a high-quality software equivalent of a modern graphics card. It takes a huge and complex scene, divides it into screen-space buckets of equal size, sorts the geometrical primitives in some way, and then (pay attention now!) tesselates and dices the primitives into micropolygons about one pixel each in size (OpenGL fragments, anyone?), shades and deforms them them using simple (or not-so-simple) algorithms written in the RenderMan shading language (hey, vertex and pixel shaders!) and then, it rasterizes them using stochastic algorithms that allow for high quality motion blur, depth-of-field and antialiasing.

Now the latest part is slightly easier for a raytracer, which can cast a ray from any place in the scene - of course, it needs this functionality anyway. But a raytracer also needs random access to the scene which means that you need to keep the whole scene in memory at all times, along with spatial indexing structures. The REYES algorithms of PRMan needs no such thing (it easily handles 2 GB of scene data on a 512 MB machine along with gigs of textures), and it allows for coherent memory access patterns and coherent computation in general (there is of course some research into coherency in raytracing, but IIRC, the results were never that good). This is a big win for graphics cards, as the bandwidth of graphics card RAM has never been spectacular - it's basically the same case as with general-purpose CPU of your computer and its main memory. But with 128 or so execution units of modern graphics card, the problem is even more apparent.

Unless the Intel engineeers stumbled upon some spectacular breakthrough, I fail to see how raytracing is supposed to have any advantage in a modern graphics card. And if I had to choose between vivid forest imagery with millions of leaves flapping in the wind and reflective balls on a checkered floor, I know what I would choose.