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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."
Kirk should talk to Picard who is quite enthused about real time raytracing.
Saying something sucks if he's already developing a product for it.
“Common sense is not so common.” — Voltaire
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.
Seriously though, does anyone expect Nvidia to say, "Yes, we really do think that our products will all be obsolete and outdated in a few years.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).
Intel says to do it with the CPU, and nVidia says to do it with the GPU. What a surprise.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
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.
I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
IBM doubts the future of the "personal computer"
Buggy manufacturers poo-poo the new horseless carriage
etc, etc.
Women are like electronics: you don't know how damaged they are until you try to turn them on.
We can't do it as well as Intel yet, therefore it sucks. BUY NVIDIA.
What about game and engine devs? Where do they see the future going?
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...)
8==8 Bones 8==8
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.
Ezekiel 23:20
"C is much too slow, to get good performance you must use assembly."
"Scripted languages are much too slow, to get good performance you must use compiled languages."
As computers get faster, there is always a move from technologies that are easier for the computer to technologies that are easier for the developer. Since ray tracing involves less hacks and is a more direct model of the effects developers want to create, it seems inevitable.
There used to be an interesting debate between Professer Philipp Slusallek of the University of Saarbruecken and chief scientist David Kirk of nVidia at GameStar.de. The original article has been taken down, but I found a slightly mangled version on the Wayback machine and I've cleaned it up a bit and put it up on my not-a-blog: link.
I'd appreciate a better translation of the German part of the text.
Following up on my previous post about the debate between David Kirk and Philipp Slusallek in 2006 (link ... apologies to Dr. Slusallek, Slashdot truncated his name).
According to Dr. Slusallek's LinkedIn profile he's currently a "Visiting Professor at NVIDIA".
The performance of Dr. Slusallek's real-time raytracing engine at only 90 MHz was quite impressive: "In contrast we have recently implemented a prototype of a custom ray tracing based graphics card using a single Xilinx FPGA chip. The first results show that this really simple hardware running at 90 MHz and containing only a small fraction of the floating point units of a rasterization chip already performs like a 8-12 GHz Pentium 4. In addition, it uses only a tiny fraction of the external memory bandwidth of a rasterization chip (often as low as 100-200 MB/s) and therefore can be scaled simply by using many parallel ray tracing pipelines both on-chip and/or via multiple chips.".
It seems there may be room for more than one opinion about the future of raytracing and gaming at nVidia.