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NVIDIA Shows Interactive Ray Tracing On GPUs

kdawson posted about 6 years ago | from the raster-fair dept.

Graphics 260

MojoKid writes "During SIGGRAPH 2008 in Los Angeles, NVIDIA is demonstrating a fully interactive GPU-based ray tracer. The demo is based purely on NVIDIA GPU technology, and according to NVIDIA the ray tracer shows linear scaling during rendering of a complex, two-million polygon, anti-aliased automotive styling application. The article reproduces screenshots from NVIDIA's demo. At three bounces (rays being traced as they bounce three times through a scene), performance is demonstrated at up to 30fps at HD resolutions of 1920x1080 for an image-based lighting paint shader, ray-traced shadows, reflections and refractions running on four next-generation Quadro GPUs in an NVIDIA Quadro Plex 2100 D4 Visual Computing System." Meanwhile reader arcticstoat passes on Intel's latest claim that rasterisation will die out the next few years, possibly in favour of ray tracing.

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Beautiful (5, Interesting)

AKAImBatman (238306) | about 6 years ago | (#24615527)

Wow, those screen caps are gorgeous. I hope this finally puts to rest the idea that rasterizing with upteenth number of features added in can compete with the image quality of Raytracing. While rasterizing may have a number of competitive features, it's hard to get the same level of specularity, reflection, shadows, shading, and other features so nicely demonstrated by this demo.

The genius of what NVidia is doing here, I think, is that by using their existing GPU architecture, they create a path by which Raytracing can be phased in as a technology without removing the support and investment in current rendering pipelines. This is a bit different from Intel's goal, which appears to be a cutoff between the old and the new.

Another interesting point is that this demo is currently capped at 3 casts per pixel. Which means that the scenes shown could look even better than they already do. Shadows could be softer, reflections could be more complex, and inventive scenes could be created to make for interesting styles of gameplay. (e.g. Fighting in a hall of mirrors.) If 3 casts/pixel is the baseline, then NVidia is setting up a vast new territory for graphical improvements. Each increase in casts/pixel will increase the realism of the scene. Thus graphical quality becomes a matter of raw horsepower. A market that I'm sure NVidia would gladly be interested in opening up.

Funny how things change, eh? [slashdot.org] :-P

Actually, I doubt NVidia has changed its position by very much. They're probably making a smart business decision and ensuring that they ride the wave of Intel's hype. If Intel *does* succeed in convincing the market that Raytracing is the future, NVidia will be ready to compete rather than cede the market.

That's a nice canned post ya got there (-1, Troll)

Anonymous Coward | about 6 years ago | (#24615579)

Story submitted: 11:00am. Your post submitted: 11:00am. There's just no way in hell you formulated a response and typed out all of that in less than a minute. So just what kind of douchebag are you, anyway?

Re:That's a nice canned post ya got there (5, Informative)

Anonymous Coward | about 6 years ago | (#24615639)

The kind with a star next to his name, obviously.

Re:That's a nice canned post ya got there (-1, Flamebait)

Anonymous Coward | about 6 years ago | (#24615727)

Well paint me black and call me a nigger, by George you're right!

Re:That's a nice canned post ya got there (4, Informative)

Colonel Korn (1258968) | about 6 years ago | (#24615789)

Story submitted: 11:00am. Your post submitted: 11:00am. There's just no way in hell you formulated a response and typed out all of that in less than a minute. So just what kind of douchebag are you, anyway?

Uh, maybe he looked at the story on the firehose.

Re:That's a nice canned post ya got there (1)

omnipresentbob (858376) | about 6 years ago | (#24617125)

That, and he's a subscriber.

Re:That's a nice canned post ya got there (4, Insightful)

jacquesm (154384) | about 6 years ago | (#24616447)

You're just sore that you didn't get to annoy a lot of people with your frist post or gnaa rubbish.

Re:Beautiful (5, Interesting)

Colonel Korn (1258968) | about 6 years ago | (#24615693)

They're probably making a smart business decision and ensuring that they ride the wave of Intel's hype. If Intel *does* succeed in convincing the market that Raytracing is the future, NVidia will be ready to compete rather than cede the market.

It's great for nVidia that they can do this with their chips, but I don't think this was done primarily for tech purposes. I think you're close to the truth when you say they can ride Intel's hype, but not quite spot on. I think this is meant to break Intel's growing ray tracing hype machine, not come along for the ride.

"Look, we can do now what you say you'll do in two years, and we can do it WAY better than you will be able to then, but on our current tech."

I can't imagine anything could be more effective at ending the "Intel will crush nVidia with ray tracing" meme that's been affecting nV stock.

Re:Beautiful (3, Funny)

mrsteveman1 (1010381) | about 6 years ago | (#24616811)

Well, once they perfect digital eyelash rendering, I'll be sold.

Re:Beautiful (3, Funny)

qoncept (599709) | about 6 years ago | (#24615707)

I suppose, but that guy could certainly use some tire-wet. Those sidewalls look awful.

Re:Beautiful (-1, Flamebait)

Anonymous Coward | about 6 years ago | (#24616175)

That shit is bad for your tires. Only pussies need shiny tires anyway.

Re:Beautiful (0, Offtopic)

mopower70 (250015) | about 6 years ago | (#24616877)

No... pussy LIKES shiny tires. And whatever the pussy likes, the pussy gets.

Re:Beautiful (4, Insightful)

Austerity Empowers (669817) | about 6 years ago | (#24616287)

I think if you look closely you'll see that they used materials very sparingly. The man behind the curtain (IMO) is that they're dedicating all their GPU and memory bandwidth to ray tracing computations, at the expensive of traditional raster manipulations.

Who cares? Well, I think if you're playing a game where you are free to run where you like, you may care.

I agree, nVidia is showing that ray tracing doesn't scare them at all. And when it's ready to happen, it will. I disagree that it's ready to happen any day now.

Re:Beautiful (2, Interesting)

WilyCoder (736280) | about 6 years ago | (#24615735)

"Another interesting point is that this demo is currently capped at 3 casts per pixel."

You mean three bounces per pixel.

Also, from TFA:

"running on four next-generation Quadro GPUs in an NVIDIA Quadro Plex 2100 D4 Visual Computing System"

Sure this is impressive, but they are pushing kilowatts to get this kind of performance.

Re:Beautiful (4, Informative)

mypalmike (454265) | about 6 years ago | (#24615947)

Every bounce casts a new ray, so "3 casts per pixel" is an accurate description.

Re:Beautiful (4, Informative)

jacquesm (154384) | about 6 years ago | (#24616505)

It isn't. More casts per pixel means that more rays are cast at slightly different angles through each pixel, and those are then averaged to yield the actual pixel colours.

Three bounces per ray simply means that a single ray can bounce three times before it's colour values are known.

Re:Beautiful (3, Insightful)

Enderandrew (866215) | about 6 years ago | (#24616055)

Intel's last demo was running on 8 GPUs wasn't it? On those were GPUs designed for ray tracing I thought.

I like Nvidia's approach to use existing architecture, and I agree with the poster above who says this is a much better method for consumers.

I disagree however with Intel saying rasterization is dying any time soon. Intel and Nvidia can't produce these effects with reasonably priced hardware, and even when the hardware becomes affordable, we still need games designed for this, and then a few years for the technology to be accepted by the masses.

I say rasterization sticks around 3-5 years.

Re:Beautiful (4, Interesting)

hr.wien (986516) | about 6 years ago | (#24615765)

They are gorgeous? Really? I think they look distinctly average. The lighting calculations look very simplistic. Yes, the shadows and reflections may be pixel perfect, but that just doesn't matter that much. You usually can't tell they are anyway. The same scene rasterized with a simple cube map for the car's reflection and some proper shadow maps would look much better. Not to mention run faster.

And "graphical quality becomes a matter of raw horsepower"? This unlike in rasterization then?

Re:Beautiful (3, Informative)

AKAImBatman (238306) | about 6 years ago | (#24615911)

Yes, the shadows and reflections may be pixel perfect, but that just doesn't matter that much. You usually can't tell they are anyway.

Sure you can. A human instinctively knows when something looks "right" or "wrong". And one of the reasons why rasterization is capped is due to lighting problems. Lighting technology has improved significantly in the last decade, but still not sufficiently to compete with raytracing. Raytraced lighting will look more natural to an untrained viewer.

And "graphical quality becomes a matter of raw horsepower"? This unlike in rasterization then?

Rasterization is heavy on hardware features to improve the quality and performance of the scene render. e.g. Blending, pixel shaders, z-buffers, etc. Ray tracing is a far simpler operation on the hardware side, though it still behooves the software side to improve the number of objects tested for rendering. (Nothing new there.)

Re:Beautiful (5, Interesting)

hr.wien (986516) | about 6 years ago | (#24616229)

Sure you can. A human instinctively knows when something looks "right" or "wrong".

Yes, and amusingly reflection and refraction (two of the main benefits of ray tracing) are a couple of things that humans generally can't tell if are being fudged. As long as it's in the ballpark it's enough to fool the human eye. Pixel perfection is way beyond what's required.

And one of the reasons why rasterization is capped is due to lighting problems.

What does that mean? Capped?

Lighting technology has improved significantly in the last decade, but still not sufficiently to compete with raytracing. Raytraced lighting will look more natural to an untrained viewer.

Why? Details please. What exactly is more realistic about tracing each pixel through the geometry than drawing the geometry directly in the appropriate pixels? The underlying lighting calculations are the same either way, meaning they will both look the same, so the only real concern is speed for any given scene.

So if we look at speed ray tracing only has a real benefit in reflection and refraction, but that's not really a winning argument because, as I said, people can't really tell if it's 100% accurate anyway. I sure can't. Ray tracing can also do accurate soft shadows relatively easily, but the ray count required makes that completely unrealistic in real time for the foreseeable future. Shadow maps will be faster either way, and look 99% as good.

Ray tracing is simple to implement, but so is cracking a password using brute force. That doesn't make it the best solution.

Re:Beautiful (1)

jacquesm (154384) | about 6 years ago | (#24616569)

I think you're missing the shadows bit completely, and they make a *HUGE* difference in what is intuitively right and what is definitely computer generated. I have a hard time with some ray traced images to tell them from the real thing (usually they're just a bit too perfect), but rasterization, no matter how well done feels 'wrong' right away.

Raytracing simply comes much closer to how things actually work and so has a much better chance of appearing natural.

Once things start moving those differences reduce, but they're still quite present.

Re:Beautiful (2, Insightful)

hr.wien (986516) | about 6 years ago | (#24616697)

The reason ray traced images often look very realistic isn't because they're ray traced, but rather because they are done offline and as such can take ages to do the calculations required for a realistic lighting model. What can be done given enough time doesn't matter. What is efficient enough to be feasible real time is.

Raytracing may be "closer to simulation", but that's completely irrelevant when the performance isn't there for the quality of the output. Can you honestly tell me you think the shadows in Nvidia's demo look better than the ones in, say, Crysis?

Re:Beautiful (1)

jacquesm (154384) | about 6 years ago | (#24616791)

I think the answer is yes, take a look at the mirror in the green car demo shot (bottom right, at high res), that's a pretty impressive following of the contours of the car by the shadow, a 'straight' computed shadow would never ever do that, compare this shot:

http://www.gamershell.com/static/screenshots/9451/264393_full.jpg [gamershell.com]

from crysis, where the shed shadow meets the terrain contour.

That's exactly the kind of thing I meant.

Re:Beautiful (1)

hr.wien (986516) | about 6 years ago | (#24616973)

The same scene using shadow maps would look more or less the same, but in addition you would have compute power left to actually make the shadow fuzzy like it is in real life. The hard shadows you get in ray tracing without sufficient light traces look anything but realistic. Especially in outdoor scenes.

I'm not sure I understand what you mean about the Crysis pic though. Looks fine to me?

Re:Beautiful (2, Interesting)

AKAImBatman (238306) | about 6 years ago | (#24616957)

What is efficient enough to be feasible real time is.

Yet in the case of Raytracing, "efficient enough to be feasible" means real shadowing, not the shadow-map crud we see in most video games.

Can you honestly tell me you think the shadows in Nvidia's demo look better than the ones in, say, Crysis?

I can and I will. Shadow maps used in games like Crysis beat you over the head with depth perspective. i.e. "Look, there's a shadow! Now you know how far off the ground the helicopter is!" While that's nice and all, only the objects that you map and define to have shadows actually cast a shadow. The subtle interactions of the environment and the actors are usually lost. It's almost like someone took a bunch of stage props, covered a stage with styrofoam sand, then threw all the props on top. Thus the actors stand out from their environment.

With ray tracing, the shadows are correct. Period. If a monster picked up that NVidia car and threw it through the air end over end, you'd see all kinds of shadow interactions happening that simply won't be visible on a shadow-mapped engine like Crysis.

Heck, you don't even have to get that complex. The car casts shadows upon itself. Which already makes it look more realistic on a closeup than anything an existing game engine can do [bit-tech.net] .

In addition, ray tracing can scale a hell of a lot farther when it comes to realistic lighting and shading. With more rays not only comes softer shadows, but multiple shadows, reflective surfaces, and other "realistic" shadowing techniques that can't be touched by today's shadow map engines.

Re:Beautiful (1)

hr.wien (986516) | about 6 years ago | (#24617103)

Heck, you don't even have to get that complex. The car casts shadows upon itself. Which already makes it look more realistic on a closeup than anything an existing game engine can do.

Bullshit. Crysis has self shadowing, just like any other moderately recent game. The screenshot you posted is in one of the lower quality modes in which it may be disabled.

Crysis also has shadows from a number of light sources simultaneously, but the number is limited (4 IIRC) for performance/quality reasons. I suggest you look up what shadow mapping actually is before you spout off nonsense.

Rasterization has moved forward since Quake 3 you know.

Re:Beautiful (1)

Dekker3D (989692) | about 6 years ago | (#24616645)

okay, i don't think those people so opposed to raytracing actually get what it means. please, do prove me wrong.

anyway, raytracing current scenes is one thing. raytracing things too complex for a rasterization-based engine is another. we could have detailed scenes using all sorts of transparancy without worrying as much about z-fighting and other detail limits.

then again, the only things i know about raytracing are based on non-realtime renders, so i may be way off.

Re:Beautiful (1)

hr.wien (986516) | about 6 years ago | (#24616887)

I'm not "opposed to raytracing". I'm opposed to the commonly held belief that raytracing automatically equals realistic graphics and that it somehow scales better than rasterization. It may if you completely ignore acceleration structures, but if you do that both ray-tracing and rasterization will run at non-realtime framerates for any moderately complex scene.

What matters is what gives the best result using the available computing power. Right now that is rasterization, and it will stay that way until the hardware is fast enough to make the extra work usually involved in making rasterization work not worth the effort in terms of quality.

Re:Beautiful (4, Insightful)

ChronoReverse (858838) | about 6 years ago | (#24615877)

What on earth? How are those overly shiny objects beautiful in any way?

The technology is probably better than that but the actual screenshots are distinctly ugly for this day and age.

Re:Beautiful (0)

Anonymous Coward | about 6 years ago | (#24616221)

What on earth? How are those overly shiny objects beautiful in any way?

You seriously ask that when some of the most popular games in existence feature overly shiny space marines? I mean, SHINY SPACE MARINES? You're worried about the shininess of a car? Did I mention, SHINY SPACE MARINES. As in, the guys you'd expect to be grimy, sweaty, and loaded with cloth. But they're not. They're SHINY.

TFA shows a car. A CAR. That's shiny. And yet you're going to complain that it's too shiny? Yeash.

Re:Beautiful (5, Informative)

Anonymous Coward | about 6 years ago | (#24616397)

The screenshots look relatively ugly because of the hashed-together-demo quality of the environment textures. But it's not a texture demo, it's a raytraced lighting demo.

Bare in mind this is ray tracing at a very rough and ready stage, but the potential is enormous. If you want to see the sort of effects it can achieve, check out some professional 3DSMax/VRay renders.

There's a nice render here [wikimedia.org] for illustrative purposes.

That's just a single frame with high quality textures, but it surely shows the potential.

Re:Beautiful (1)

Oasiz (1017554) | about 6 years ago | (#24616451)

Cmon, can't you see? You can live those 'glorius' 90's pre-rendered backgrounds in realtime ! ;)

Re:Beautiful (3, Insightful)

phantomfive (622387) | about 6 years ago | (#24616691)

Yeah, exactly...it's like Web2.0 of the graphics world....sure, the buttons are shiny, but that doesn't make them look any better. That is why people like John Carmack have suggested that full on ray tracing isn't the way to go.

I absolutely do not understand the issue fully, but here is my take: in the early 90s, ray traced graphics looked way better than anything else. You could render a ball and people would say, "wow, that is so cool!" it took 30 minutes to render, but it could be done.

Since then, 3D rasterization has come a long way. With texture mapping, commodity 3D graphics hardware, pixel shading, alpha blending, etc, we have games that look really, really good, without ray-tracing.

Now ray-tracing is starting to become possible in real time, and I guess people are remembering how good it looked in the 90s and thinking it must still be the holy grail of graphics. In theory it's a good idea, render everything the way real light does.

The ultimate question has to be: does it look better? Or is there another way we can use that processing power that will make the graphics look even better? My guess is that ray-tracing is a technique that will be useful in some ways, and will be mixed with techniques we already have now. Much like today we use 2D texture maps on 3D objects, and it looks good.

Re:Beautiful (1)

Stalus (646102) | about 6 years ago | (#24616015)

Shadows could be softer

They only mention three bounces per pixel, and do not mention samples per pixel. They also don't give any detail about their light sources. If they maintain point light sources, the shadows will always be hard no matter how many bounces or samples they take. If they allow area light sources, and sample it properly, they can do that with a single bounce. And you can do some pretty nice stuff with three bounces.

Re:Beautiful (0)

Anonymous Coward | about 6 years ago | (#24616059)

Yes, the ultimate in image quality is clearly the domain of ray tracing. That's why all the film vfx guys used ray trace based renderers.

Oh wait...

Re:Beautiful (1)

Hairy Heron (1296923) | about 6 years ago | (#24616919)

Oh wait...

That must be why most of the 3D CGI in films sticks out so much.

Re:Beautiful (2, Insightful)

BiggerIsBetter (682164) | about 6 years ago | (#24616149)

They're nice work, but c'mon, how about some demo VIDEO instead? I'd love to see the full effect of the reflections in the Windows and chrome of the wheels, and the way the lighting moves...

Re:Beautiful (1)

Thought1 (1132989) | about 6 years ago | (#24616599)

The genius of what NVidia is doing here, I think, is that by using their existing GPU architecture, they create a path by which Raytracing can be phased in as a technology without removing the support and investment in current rendering pipelines. This is a bit different from Intel's goal, which appears to be a cutoff between the old and the new.

Intel tried the same thing with IA64, while AMD went the x64 route. Guess which approach will win this one, too? (:

Re:Beautiful (1)

samkass (174571) | about 6 years ago | (#24616695)

One thing I noticed is that the curves and shiny surfaces look really, really smooth but that the straight lines look aliased and fake. The railings look like they were drawn in with a line tool.

Re:Beautiful (1)

Phat_Tony (661117) | about 6 years ago | (#24617025)

Funny how things change, eh?

I think Nvidia would have preferred a different previous naysayer for you to link to [slashdot.org] .

I heard the title of their talk at SIGGRAPH was:
"Practical Real Time HD Raytracing With Nvidia Hardware: Suck It, John Carmack."

"favour"? (-1)

Anonymous Coward | about 6 years ago | (#24615583)

Pip pip, cheerio, old bean! Jack's a doughnut, let's pop down to the pub for a pint and some bangers and mash.

Re:"favour"? (1)

oldspewey (1303305) | about 6 years ago | (#24615927)

You missed birchbark canoes, the Trailer Park Boys, real beer, Timmy's, the CBC, and back bacon eh?

What's the power consumption on that rig? (3, Funny)

Rogerborg (306625) | about 6 years ago | (#24615613)

Al Gore would like to have a word with you about just how important it is to beat photo-realistic hookers to death.

Re:What's the power consumption on that rig? (0)

Anonymous Coward | about 6 years ago | (#24616071)

haha what Al dislikes even more is that the Bugatti Veyron in the photos gets about 3 mpg.

Re:What's the power consumption on that rig? (1)

maxume (22995) | about 6 years ago | (#24616581)

He doesn't mind if you do it, he just wants you to call it a privileged and to pay someone for it.

Re:What's the power consumption on that rig? (1)

Rogerborg (306625) | about 6 years ago | (#24617163)

Maybe a hooker trading scheme? You can beat a ray traced hooker to death if you can offset it against someone beating an 8 bit bitmap hooker to death?

Re:What's the power consumption on that rig? (0)

Anonymous Coward | about 6 years ago | (#24616713)

Have you seen's Al Gore's setup [time.com] ?

Re:What's the power consumption on that rig? (0)

Anonymous Coward | about 6 years ago | (#24617175)

Eliot Spitzer might have a problem with Al Gore.

I've got an idea (0, Troll)

initdeep (1073290) | about 6 years ago | (#24615695)

How about they focus instead on correcting the issue with their mobile chipsets which they are studiously avoiding making right with any of the people who have had issues.

Re:I've got an idea (1)

Abcd1234 (188840) | about 6 years ago | (#24616639)

Yes, because no corporation can possibly two do things at the same time...

Re:I've got an idea (1)

LingNoi (1066278) | about 6 years ago | (#24616911)

Apparently they're not which is the GPs point.

hmm. (1)

apodyopsis (1048476) | about 6 years ago | (#24615711)

I had a tenant once, who stated that the first use of any new multimedia technology was always for, shall we say, *adult* services. In the sense they drove DVD sales (multi viewpoint, stop rewind), CGI, and so on.

gah. the mind boggles what the animation crowd could do with this.

On a similar note, when I did my BA years ago my dissertation was on the veracity of digital images, when there is no real referent to accompany the photograph, and the loss of credibility of images in the onslaught of photo realistic fakes.

Well, it was inevitable that technology would catch up and we will no doubt need to add "video realistic" to our dictionary as well.

Just give me silver halide and call me a Luddite.

Not quite yet, I'm affraid (3, Interesting)

Moraelin (679338) | about 6 years ago | (#24616173)

Actually, I think that the biggest problem with animated porn isn't texturing-vs-raytracing, but the models and animations. Last time I ran into some adult Poser-fu, it looked all wrong in a massively uncanny-valley way, and not because of the texturing.

And with the animations, well, I'd assume it's actually easier and cheaper to find a gal who'll bounce on a cock for half an hour for a few (thousand) bucks, than a highly skilled artist and animator who'll make that look natural.

Plus, raytracing is IMHO entirely the wrong secret sauce there. Ray tracing works best for sharp, metallic/mirror reflections. Because then you can take each ray and reflect it as one ray. If you want to go diffuse, that's a lot more expensive with ray-tracing. Then you need to split each ray into sub-rays that reflect into slightly different directions from there. Same as anti-aliasing is done by calculating sub-pixels, basically.

I.e., ray tracing looks grrreat and is the cheapest for shiny cars, crystal cups, and the like. Which is why everyone ray-traces cars and the like. It sucks for something like human skin, unless, of course, you want to make those humans look like polished shiny plastic dolls.

So, well, I can't imagine that much need for it in porn at the moment. Unless, of course, you want to make a Transformers sex movie. Or maybe one with liquid- metal Terminators fucking. (Hey, they must have made some female versions too, right?;)

Re:hmm. (1)

mopower70 (250015) | about 6 years ago | (#24616915)

Wow. If only we could limit nonsequiturs to three bounces a post.

don't quit your day job quite yet (5, Informative)

Ancient_Hacker (751168) | about 6 years ago | (#24615723)

The devil is in the details. Ray tracing with glossy surfaces is relatively easy. But if you want to simulate real-world textures like orange-peel, bark, hair, or skin, things can really slow down.

Re:don't quit your day job quite yet (0)

Anonymous Coward | about 6 years ago | (#24616021)

Hey man, I don't know what kind of weird stuff you're into, but I do perfectly fine without any orange peel, bark, hair or... oh wait.

Re:don't quit your day job quite yet (1)

MadnessASAP (1052274) | about 6 years ago | (#24616109)

Bark isn't too hard to pull off at least form a technical standpoint, from an artistic standpoint it can of course be a bitch to pull off but that's a different matter. Hair is a bit trickier but you can usually get decent enough looking results. Orange peel has a bit of Sub Surface Scattering (SSS) but in most scenes you can again get away without it.

So that leaves skin, for a long time realistic skin was almost the holy grail for CGI given that SSS and multiple layers are a huge component of skin but now for pre-rendered images the technology and the horsepower is largely in place to pull it off. Of course this is about RT raytracing so I can expect that it will be quite a while(on a technological timeline) before your average desktop computer can render skin in les then a minute much less 30 times a second.

Re:don't quit your day job quite yet (1)

Big_Breaker (190457) | about 6 years ago | (#24616411)

At least in the beginning I imagine skin features like you descibe would be pre-rendered into the texture as some sort of efficiency compromise. It's not like raster methods do a great job right now anyway. Most games are still going further into uncanny valley rather than climbing out of it.

Re:don't quit your day job quite yet (0)

Anonymous Coward | about 6 years ago | (#24616843)

I don't think "pre-rendered" subsurface scattering really counts as subsurface scattering.

Re:don't quit your day job quite yet (3, Insightful)

Ambiguous Coward (205751) | about 6 years ago | (#24616281)

Umm, no. I admit it's been a while, so my memory may be off, but I distinctly recall that procedural textures in ray-tracing are really, really easy, and add almost no (necessary) overhead to speak of. If you can find a way to do those things you mentioned with a procedural texture (those cases you provided are the textbook examples of how to do procedural textures, mind you) then you can almost certainly do them easily and cheaply. Any graphics course will have you rendering textured oranges inside the first week of the ray-tracing portion. Rainbowed CD undersides and the cool microscopic rings on the underside of a brass pot the day after that.

I don't remember the implementation details, as it's been many years since I tried, but it's easy, and doesn't add any real overhead to speak of. Yes, when running procedural textures, you CAN make them heavy (it's a procedure: it'll do whatever the hell you want) but by no means is that a requirement.

Which do you think is worse:

  • Loading a 10MB texture image that only works at certain resolutions, and eats up 10MB of space, or
  • Loading up a 1k code segment that generates the same (or similar) texture at any resolution, on the fly, and only generates the texture for the exact pixels you're looking at?

Not to mention that if anything even close to the support given to the current texture models is given to procedural texture models, they will almost instantly outpace the current options and limitations.

Did you ever notice that the early-generation ray-tracers supported procedural textures long before they supported the "regular" texturing model? There's a reason for that.

-G

P.S. Yes, I'm fully prepared for nit-picking you-used-the-wrong-word-here responses, so fire away. :P

Re:don't quit your day job quite yet (1)

Ambiguous Coward (205751) | about 6 years ago | (#24616337)

Everything else I said above left aside, I think what I'm really driving at was this one statement:

...if anything even close to the support given to the current texture models is given to procedural texture models, they will almost instantly outpace the current options and limitations.

-G

Re:don't quit your day job quite yet (1)

MobileTatsu-NJG (946591) | about 6 years ago | (#24616821)

Which do you think is worse:
Loading a 10MB texture image that only works at certain resolutions, and eats up 10MB of space, or
Loading up a 1k code segment that generates the same (or similar) texture at any resolution, on the fly, and only generates the texture for the exact pixels you're looking at?

If you're running more lines of code per pixel with a procedural than you are by simply looking up a memory location for an rgb value, how is that going to be 'no overhead'?

Maybe I'm misunderstanding a fundamental concept of how raytracing works, so I won't be ashamed or argumentative if you can correct me on this, but I don't get how raytracing will make procedurals run nearly as fast when the renderer is going to have to ask a shitload of questions per-pixel about what that color is supposed to be. Do forgive me, though, I'm only really thinking of real-world use of procedurals that'd actually compete with high res textures, not simple marble patterns.

Re:don't quit your day job quite yet (1)

caywen (942955) | about 6 years ago | (#24616503)

I'm admittedly only very journeyman in my understanding of RT (I've written some basic RT's). How would they slow down? You can process bump maps pretty easily - it's still just adjusting the diffuse light value based on a tweaked surface normal.

Re:don't quit your day job quite yet (1)

oliverthered (187439) | about 6 years ago | (#24616567)

that's all fine and well, but it sure looks a lot sexier (proper curved surfaces) than rasterization which is what it's competing with

Of course Intel would say that... (0)

Anonymous Coward | about 6 years ago | (#24615739)

It takes a lot of CPU power to raytrace at that level, and hey, what's that Intel is selling?

What a waste of resources (5, Insightful)

rogerbo (74443) | about 6 years ago | (#24615777)

I just looked at those pictures and then checked a high res shot of Gran Turismo 3 Prologue on a PS3:

http://o.aolcdn.com/gd-media/games/gran-turismo-5-prologue/playstation-3/22.jpg

I don't see enough of an improvement to increase GAMEPLAY in any significant way. The reflection maps and shadows that are created by the current rasterization tricks are good enough that you suspend disbelief.

I'd much rather the increase in GPU power be used through a GPGPU API for artificial intelligence, advanced physics simulations, fluid dynamics, flocking behavior or other things which could really add to gameplay.

A few extra reflections and slightly softer shadows???? I won't even notice and neither will the average gamer.

Re:What a waste of resources (4, Insightful)

jamie (78724) | about 6 years ago | (#24615999)

I kind of assumed the big win was that game development gets easier. If your game is rendered by ray-tracing can't you spend more time on building the models, lighting and gameplay and less on fine-tuning rendering tricks?

Re:What a waste of resources (0)

Anonymous Coward | about 6 years ago | (#24616105)

Problem is we are reaching the design limitations of the current technology, whilst ray tracing is currently primitive it has a bigger future then the current tech.

Re:What a waste of resources (4, Informative)

Big_Breaker (190457) | about 6 years ago | (#24616193)

The gameplay improvement is in deformable physical environments. Combined with mainstream physics engines, raytracing would allow for a sea-change in gameplay by allowing interactive gaming environments.

Raster methods rely on a bunch of tricks, many of which need to be precalculated for static maps. The most obvious example is binary space partioning tables. This leads to very static feeling environments that disallow interaction beyond doors of various types and moving platforms.

Re:What a waste of resources (1)

fluffykitty1234 (1005053) | about 6 years ago | (#24616323)

Hmm? I don't think so. BSP trees and other tricks like this allow you to only draw what's visible. When you are ray-tracing you would still need a way to prune away geometry that isn't visible, or it would take forever to find ray itersections.

Re:What a waste of resources (1)

jacquesm (154384) | about 6 years ago | (#24616701)

Better yet, you have to have a way to prune that which is not reflecting into an area that is visible!

And then there's all kind of colour-bleed effects, they can also come from objects that are out of the directly visible area. Light sources, particles in your simulated atmosphere that light can scatter off and so on. There's a lot that goes into deciding which parts of your scene are 'active'.

Re:What a waste of resources (1)

caramelcarrot (778148) | about 6 years ago | (#24616661)

Uh, you do know that in order to do ray-tracing efficiently, you have to use data structures like bsps, kdtrees and octrees? I.e. Ones that you don't want to have to rebuild every frame because something moved. I get your point that you won't have to precompute lighting for radiosity, but even raytracing often using radiosity for global illumination.

Re:What a waste of resources (1)

Big_Breaker (190457) | about 6 years ago | (#24616845)

I see your point and the point of fluffykitty. I guess my intuition is that the tricks are piled on so thick in your typical raster based FPS engine that in order to simulate lighting, reflections and transparency effects certain things, like the environment, need to remain static.

Raytracing addresses some of these shortcomings of raster so that these tricks need not be used, a more ground up approach. That way the environment can be more dynamic as its features are recalculated in real time.

Re:What a waste of resources (1)

pak9rabid (1011935) | about 6 years ago | (#24616237)

I'd much rather the increase in GPU power be used through a GPGPU API for artificial intelligence, advanced physics simulations, fluid dynamics, flocking behavior or other things which could really add to gameplay.

I think you're missing the purpose of what a graphics processing unit is for.

Re:What a waste of resources (1)

roystgnr (4015) | about 6 years ago | (#24616929)

I think you're missing the purpose of what a graphics processing unit is for.

No, he's going beyond the purpose of what a graphics processing unit was originally for, and looking ahead to what General Purpose GPU computing [wikipedia.org] is going to [gpgpu.org] be for. [nvidia.com] There's nothing in the GPU that requires it to operate on polygons; the silicon is there to do parallel stream processing, and streams of geometry/texture/lighting/etc data are just one of the ways to use that.

Re:What a waste of resources (0)

bmajik (96670) | about 6 years ago | (#24616779)

I think the big benefit here is that scenes will be considerably more realistic, especially under motion.

GT has never done an _authentic_ job at anything. Most of its vehicle physics and eye-candy are faked, and in the case of vehicle dynamics, badly.

In the GT shot you've posted, the cars appear to have reflective surfaces, interacting shadows, etc. But the background doesn't. Why not? Becuase people look at cars.

Now look at the nVidia shot. Note that you can see the sign and bridge geometry reflected in the glass of the building. What are the odds that, if you had to explicitly program for this behavior, that a developer would bother to render accurate geometry reflections into individual panes of glass on a building.

That's computationally expensive, it takes a lot of programmer protein power, and it's just not something you'll see done with game-style renderers.

But raycasting and other light-simulation techniques are interesting precisely because they aren't optimized for any particular application (i.e. cars that look wet in dead boring backgrounds).

I think that as scene rendering and lighting becomes more general (instead of relying on tricks for certain desired effects), scenes will become over all more realistic, and things will start happening that nobody expected or planned for.

The "shadows" in that GT shot are awful. I don't want a vague, aliased, dark-map cast uniformly off the front glass. I want the reflection of the building to be cast over the windshield. I want the curvature of the glass to be apparent because the reflection has distorted over its contours. I want the reflected building to be translucent because when looking at a reflection on a peice of glass, there's a mix of reflection and transmission. Since the reflected building it itself covered in glass, i want to see reflected reflections on the windshield. Since light energy is lost at each reflective stage, i expect there to be more image attenuation between the 1st and 2nd reflected images.

And I want all of it to move and change realistically as the car moves (and the building doesn't).

It's not that this level of accuracy will make racing more fun (or that it would affect me anyway since i use exclusively in-car views (although it would be cool to see glare/reflection across the glass modelled properly!), it's that the world will become more accurate and immersive _in general_ in ways that developers didn't plan for.

Procedurally trying to acheive this effect is going to be painful. Shooting light energy into a completely described 3d world and letting the chips fall where they may is easier and more accurate. The issue is that it's never been plausible for real time applications.

nAwesome (0)

Anonymous Coward | about 6 years ago | (#24615785)

I love this company. Always moving ahead.

No Dirt... (1)

griffman99h (671362) | about 6 years ago | (#24615857)

...there's still no dirt. I wont be impressed till I see some grime build up on a fender in realtime.

Re:No Dirt... (3, Funny)

Tubal-Cain (1289912) | about 6 years ago | (#24616441)

Head up the stairs (to ground level), down the hall, and out the door. You should be able to find a bumper to stare at for a few hours.

Of course, but when? (5, Insightful)

MojoRilla (591502) | about 6 years ago | (#24615903)

Of course ray tracing, or one of its decendants, like photon mapping [wikipedia.org] , will end up dominant. The question is when. Ray tracing is used now for rendering movies like Cars [computer.org] , which are probably pretty much state of the art for computer graphics, and would be used for things like PC games except that is so computationally expensive.

As to when rasterization will be replaced, the short answer is not any time soon. The article's title is misleading. It says "Intel: Rasterisation will be replaced in five years", while Intel's ray tracing guru Daniel Pohl actually says "Looking ahead five to ten years from now, I believe that rasterisation will be used less and less in games". Big difference there.

So, I think this will progress quickly, but we won't be getting rid of rasterization any time soon.

Re:Of course, but when? (1)

kripkenstein (913150) | about 6 years ago | (#24616353)

I tend to agree. While ray tracing has a lot of potential, it is several years away from being usable on mainstream hardware, and in addition, during that time rasterization technology will further improve. So even if this demo will work on gaming PCs in 5 years, rasterization graphics may look amazingly better by that time.

Re:Of course, but when? (1)

Hoi Polloi (522990) | about 6 years ago | (#24616677)

Maybe the best course would be to selectively use ray tracing. Use rasterization for backgrounds and other low visibility or undynamic images and use ray tracing for the focus of the viewer's attention. That dragon you are fighting may benefit from ray tracing but the tree behind it in the far distance could just be rasterized.

Re:Of course, but when? (1)

pr0nbot (313417) | about 6 years ago | (#24616509)

IThe thing I like about ray tracing is that it's more or less pure physics (as opposed to current GPU rendering is a clever box of tricks and hacks and approximations). So, you can implement a glorious renderer today, and just wait for the hardware to catch up.

good but... (1)

Bizzeh (851225) | about 6 years ago | (#24615973)

this looks pretty nice, and its cool that nvidia are working on getting ray tracing methods down to an acceptable level of processing... but the problem i can see with this.... everything within all those images looks like its made from the same plastic that samsung tvs are made out of... everything is... TOO reflective.

Seen it (0)

Anonymous Coward | about 6 years ago | (#24616013)

The article mentioned something about Intel doing this with a Quake 3 engine. I remember seeing some guys who built their own GPU using a FPGA that did hardware ray tracing using a modified version of the Quake 3 engine when it first went open sourced. They couldn't do anything real time because of the speed restrictions of an FPGA but I remember it looking as good or better than this. Good to know that the professional hardware developers are finally catching up with the hobbyists.

Still waiting... (5, Funny)

Ukab the Great (87152) | about 6 years ago | (#24616045)

I want NVIDIA to come out with a card that gives boring DOOM clones intriguing plots and compelling gameplay.

Re:Still waiting... (1)

kenp2002 (545495) | about 6 years ago | (#24616853)

I can fix it:

East side cop finds his ex-wife dead and he's the primary suspect.

Digging into the murder he finds his wife moonlighting with a weird cult operating out of the boiler room of a massive fast food corporation.

They open a gate to hell, the cop gets possessed and proceeds to murder the entire city as a demon.

Once the last soul is taken the gate seals up and the event becomes a cold case.

30 years later: An ex-army gone PI chases down a filandering wife and her boyfriend to the ruins of an abandon metropolis in the western part of Brazil where something bad happened 30 years ago...

I wonder (2, Insightful)

ThePhilips (752041) | about 6 years ago | (#24616077)

Meanwhile reader arcticstoat passes on Intel's latest claim that rasterisation will die out the next few years, possibly in favour of ray tracing.

I'd love that to happen.

But reality is that several best games I have played were ... 2D.

Intel, Good luck adding RT to 2D graphics. ;)

RT in my experience is rather expensive - on end of development. Not all games manage to exploit all lighting models. And RT needs that even more than actual 3D graphics. It would take some long time for games to adopt it. On side of CADs picture is much simpler: they are easy to fork $$$ for good and fast rendering.

What this will mean for games (4, Funny)

Tibor the Hun (143056) | about 6 years ago | (#24616147)

Like someone said a few months back, now all the games will be composed entirely of shiny balls, toruses, and checkerboards.

Re:What this will mean for games (4, Funny)

CaseyB (1105) | about 6 years ago | (#24616407)

Don't forget teapots!

Re:What this will mean for games (0)

Anonymous Coward | about 6 years ago | (#24616413)

Like someone said a few months back, now all the games will be composed entirely of shiny balls, toruses, and checkerboards.

You forgot teapots.

Pity they don't include an RPU (1)

argent (18001) | about 6 years ago | (#24616271)

Slusallek's RPU was doing real-time raytracing with about the same hardware as Rage Pro, three years ago.

They could afford to put a couple of souped up RPUs in the corner of a GPU without noticing the "lost" transistors and get this kind of real-time raytracing on entry-level GPUs *today*.

plu5 2, TrolL) (-1, Offtopic)

Anonymous Coward | about 6 years ago | (#24616291)

abouat bylaws

Back at you... (0)

Anonymous Coward | about 6 years ago | (#24616321)

So what if Intel thinks Ray Tracing is the future, I doubt it will happen anytime soon and I don't think the Larrabee will offer anything good for rasterisation now. It will be garbage just like there current GMA offerings.

This is just Nvidia saying to Intel "If you think you can get ahead by your claims of ray tracing being the only future we'll show you we can do ray tracing and not only compete with you but we will crush the Larrabee GPU."

I, for one, welcome our ray traced overlords (3, Interesting)

caywen (942955) | about 6 years ago | (#24616389)

I think raytracing is going to be the only way to go in 5-10 years. As poly counts go up, average poly size is going to drop below 1 pixel, and the overhead of tracing rays will match the overhead of rasterizing tiny polys + scene overdraw, etc. Of course, what I fear is that all the games will start feature too much reflection on every surface, because they can.

Re:I, for one, welcome our ray traced overlords (0)

Anonymous Coward | about 6 years ago | (#24617157)

Poly counts aren't going to get that high because perf takes a nosedive when the polygons are less than 4 or 16 pixels.

Scene search (1)

caywen (942955) | about 6 years ago | (#24616665)

I wonder how much control future ray tracing engines will give the programmer over scene search algorithms? If I'm doing a top-down terrain render, I'd want to have a super-simple O(C) first hit time (probably using a simple grid/bucket). If I were doing a space scene, maybe an oct tree. In either case, it sounds like a problem that can't easily be hardware accelerated.

mTo3 down (-1, Offtopic)

Anonymous Coward | about 6 years ago | (#24616825)

and Juliet 40,000 the offdicial GAY

Crysis now run? (1)

TheDarkMaster (1292526) | about 6 years ago | (#24616875)

Maybe will be possible to play Crysis now

Is that you, Pete Shirley? (1)

Aidtopia (667351) | about 6 years ago | (#24617083)

I wonder if this is what Pete Shirley [blogspot.com] went to NVIDIA to do.

The article and some of the comments here have oft-repeated myths about ray tracing. For example, ray tracing algorithms are generally simpler than rasterization algorithms, not more complex--though they do require more processing power.

One commenter said this demo was limited to 3 rays per pixel. That may not be true. The article said each ray was limited to 3 bounces. That doesn't preclude firing multiple primary rays per pixel for antialiasing. From the images, though, it doesn't look like there's much antialiasing.

I'm also disappointed to read that it's still done with bajillions of polygons. One potential advantage of ray tracing is rendering smooth, curved surfaces. Few of the real-timers seem to attempt this though. Too bad, the savings in memory for the model could improve the transform and rendering times.

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