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Intel Researchers Consider Ray-Tracing for Mobile Devices
Posted by
Soulskill
on Sun Mar 02, 2008 08:27 AM
from the smaller-pretty-pictures dept.
from the smaller-pretty-pictures dept.
An anonymous reader points out an Intel blog discussing the feasibility of Ray-Tracing on mobile hardware. The required processing power is reduced enough by the lower resolution on these devices that they could realistically run Ray-Traced games. We've discussed the basics of Ray-Tracing in the past. Quoting:
"Moore's Law works in favor of Ray-Tracing, because it assures us that computers will get faster - much faster - while monitor resolutions will grow at a much slower pace. As computational capabilities outgrow computational requirements, the quality of rendering Ray-Tracing in real time will improve, and developers will have an opportunity to do more than ever before. We believe that with Ray-Tracing, developers will have an opportunity to deliver more content in less time, because when you render things in a physically correct environment, you can achieve high levels of quality very quickly, and with an engine that is scalable from the Ultra-Mobile to the Ultra-Powerful, Ray-Tracing may become a very popular technology in the upcoming years."
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Technology: Ray Tracing for Gaming Explored 266 comments
Vigile brings us a follow-up to a discussion we had recently about efforts to make ray tracing a reality for video games. Daniel Pohl, a research scientist at Intel, takes us through the nuts and bolts of how ray tracing works, and he talks about how games such as Portal can benefit from this technology. Pohl also touches on the difficulty in mixing ray tracing with current methods of rendering. Quoting:
"How will ray tracing for games hit the market? Many people expect it to be a smooth transition - raster only to raster plus ray tracing combined, transitioning to completely ray traced eventually. They think that in the early stages, most of the image would be still rasterized and ray tracing would be used sparingly, only in some small areas such as on a reflecting sphere. It is a nice thought and reflects what has happened so far in the development of graphics cards. The only problem is: Technically it makes no sense."
Submission: Ray-Tracing in your Pocket? by Anonymous Coward
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Games: Carmack Speaks On Ray Tracing, Future id Engines 256 comments
Vigile writes "As a matter of principle, when legendary game programmer John Carmack speaks, the entire industry listens. In a recent interview he comments on a multitude of topics starting with information about Intel, their ray tracing research and upcoming Larrabee GPU. Carmack seems to think that Intel's direction using traditional ray tracing methods is not going to work and instead theorizes that using ray casting to traverse a new data structure he is developing is the best course of action. The 'sparse voxel octree' that Carmack discusses would allow for 'unique geometry down to the equivalent of the texel across everything.' He goes on to discuss other topics like the hardware necessary to efficiently process his new data structure, translation to consoles, multi-GPU PC gaming and even the world of hardware physics."
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Inverse Moore's Law (Score:5, Insightful)
Inverse Moore's Law states that the more time that developers spend on making games look 'pretty', the less time they spend on playability.
Re:Inverse Moore's Law (Score:5, Funny)
Parent
Re: (Score:2, Informative)
Re: (Score:3, Interesting)
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Strap it on your noggin and immerse... or pick it up and dial.
Re:Inverse Moore's Law (Score:5, Insightful)
Parent
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Re:Inverse Moore's Law (Score:5, Informative)
Current rasterization approaches use a lot of approximations, it's true, but they can get away with that because in interactive graphics, most things don't need to look perfect. It's true that there's been a lot of cool work done lately with interactive ray tracing, but for anything other than very simple renderings (mostly-static scenes with no global illumination and hard shadows), ray tracers *also* rely on a bunch of approximations. They have to: getting a "perfect", physically correct result is just not a process that scales well. (Check out The Rendering Equation on wikipedia or somewhere else if you're interested; there's a integral over the hemisphere in there that has to be evaluated, which can recursively turn into a multi-dimension integral over many hemispheres. Without cheating, the evaluation of that thing is going to kick Moore's law's ass for a long, long time.)
By the way, the claim that with a "physically correct environment, you can achieve high levels of quality very quickly" doesn't really make much sense. What's a "physically correct environment" and what is it about rasterization that can't render one? How are we defining "high levels of quality" here? And "very quickly" is just not something that applies much to ray tracers at the moment, especially in the company of "physically correct".
Parent
Re: (Score:2, Informative)
Re:Inverse Moore's Law (Score:4, Informative)
And about scalability, you're right, of course; ray tracing does scale better with scene complexity than rasterization does, and as computing power increases it will make more and more sense to use ray tracing. However, the ray tracing vs. rasterization argument has been going on for decades now, and while ray tracing researchers always seem convinced that ray tracing is going to suddenly explode and pwn the world, it hasn't happened yet and probably won't for the forseeable future. Part of it is just market entrenchment: there are ray tracing hardware accelerators, sure, but who has them? And although I've never worked with one, I'd imagine they'd have to be a bit limited, just because ray tracing is a much more global algorithm than rasterization... I can't see how it'd be easy to cram it into a stream processor with anywhere near as much efficiency as you could with a rasterizer. On the other hand, billions are invested into GPU design every year, and even the crappiest computers one nowadays. With GPUs getting more and more powerful and flexible by the year, and ray tracing basically having to rely on CPU power alone, the balance isn't going to radically shift anytime soon.
For the record, although I do research with both, I prefer ray tracing. It's conceptually simple, it's elegant, and you don't have to do a ton of rendering passes to get simple effects like refraction (which are a real PITA for rasterization). But when these articles come around (as they periodically do on Slashdot) claiming that rasterization is dead and ray tracing is the future of everything, I have to laugh. That may happen but not for a good long while.
Parent
photon mapping (Score:3, Interesting)
Photon mapping is a pretty good way of getting an unbiased approximation
Sweet!! (Score:2, Funny)
Can't wait for my contacts list at sunset! (Score:3, Interesting)
A popular technology? Like a working filesystem? They're real popular I hear. Or an o
Brilliant! (Score:5, Funny)
"Holy Crap! Mobile gaming devices have tiny screens, imagine how easy it'd be to use advanced raytracing graphics!"
"Brilliant!"
Re: (Score:2)
"Hmmm....."
(long pause)
"What about rendering really small scenes on a big stonking server and then using some sort of 'Network' to make the images appear?"
"That sounds like some kind of magic!"
Fantastic research [acm.org].
"computational requirements" (Score:3, Insightful)
This attitude is why even tho our computers are 1000x faster then we had 20 years ago, they actually perform worse overall.
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This attitude is why even tho our computers are 1000x faster then we had 20 years ago, they actually perform worse overall.
I would say yes and no. Its one thing to have the computer do something simply becase it can; I agree that is very wasteful. Raytracing is not needed on a 300x200 screen; especically while plaing a game and things are moving.
On the otherhand 20 years ago like today we compormised and dispensed with things or found was to "fake it" in cases where the computer's conuld not deliver. Its really not critical shadows are rendered perfectly on my mobile phone while I am playing Doom57 Mobile Edition. An arch
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20 years ago, no one was connected to a 3mbps line, listening to music, with a mail and an IM client constantly pinging back, watching a video on youtube in one of twenty tabs in my firefox, with vim/emacs/eclipse open, azureus plugging away at some torrents as fast as it could, on two 1280x1024 screens in real colour, all simultaneously, on a single core I bought years ago. I still don't notice significant slowdowns.
prog10 (Score:5, Funny)
Re:prog10 (Score:5, Informative)
Parent
Summary is misleading (Score:3, Informative)
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Doubling the number of transistors on an LCD does not double the resolution (as you pointed out), it only multiplies each dimension by the square root of 2. Doubling the number of transistors on a CRT does nothing (well, maybe it gives you a more impressive OSD). But even limiting it to LCDs, it does not hold up. Display resolution
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http://en.wikipedia.org/wiki/Eye#Acuity [wikipedia.org]
http://www.dansdata.com/gz029.htm [dansdata.com]
Piggy-backing on Dan's hand waving, 300 dpi at 1 foot is a decent rule of thumb, and waving my own hands, 1 foot is a reasonable minimum distance for a handheld device(I don't imagine most people holding something any c
Good for Intel, needs more work (Score:5, Interesting)
Lockout chip business model (Score:2)
Ray casting and Java (Score:3, Interesting)
And this is just for Ray Casting which is much simpler than Ray Tracing.
During my development with Java I discovered that setting a pixel color to 0xFF000000 caused a slowdown. That's right, a black pixel would slow the framerate down. I had to set all pure black
Battery Life vs Graphics (Score:3, Insightful)
Ray-tracing may be possible on my 500Mhz smartphone's processor - but damn, I don't want to have to be plugged in to play them.
Imagine a Beowolf cluster of those.... (Score:3, Funny)
I can image that, but... (Score:2)
Existing Real-Time Ray-Tracers? (Score:2)
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It looks like Povray [povray.org] is experimenting with one.
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Real time raytracing with POV-Ray (Score:4, Informative)
Not sure I get their argument (Score:2)
If this is the case, why not just use the increasing processing power to produce better quality graphics using the current optimized techniques?
Am I missing something? Intel's argument seems a bit like saying we should get rid of QuickSort and go back to Bubble so
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Raytracing is not the holy grail of graphics (Score:5, Informative)
Pixar is not the holy grail of graphics (Score:2, Informative)
What does Pixar have to do with realtime graphics? (Score:3, Interesting)
Pixar has the luxury of controlling every take, and going back after the fact to re-render shots with different settings, or even to use different algorithms (including ray-tracing) to fix any rendoring flaws caused by whatever approximations they're using at that point. Realtime graphics do not have that luxury... if there's a problem in a scene, you can't go back and fix it.
So whether raytracing is more or less appropri
Re:Raytracing is not the holy grail of graphics (Score:4, Informative)
Actually Pixar has switched to Ray Tracing. Cars was ray traced [pixar.com] [PDF]. Skimming through the whitepapers on the Pixar site [pixar.com], it's clear ray tracing was also used extensively in Ratatouille.
Even so, what Pixar is doing in feature films isn't particularly relevant to real-time ray tracing on mobile devices.
Parent
it's about memory, not performance or realism (Score:4, Informative)
It's worth pointing out (and it's mentioned in the paper you cite) that the main reason Pixar hasn't been doing much ray tracing until now is not performance or realism, but memory requirements. They need to render scenes that are too complex to fit in a single computer's memory. Scanline rendering is a memory-parallel algorithm, ray tracing is not. So, they're forced to split the scene up into manageable chunks and render them separately with scanline algorithms.
This isn't an issue for games, which are going to be run on a single machine (perhaps with multiple cores, but they share memory).
Parent
Re: (Score:3, Interesting)
Ray tracing alone is not a silver a bullet but if it produces better results with less human effort, it's a net win.
I found this on Pixar's RenderMan page (https://renderman.pixar.com/products/tools/renderman.html):
"Ray Tracing and Global Illumination
The ray tracing and
Intel is nuts. Raytracing is not easier. (Score:2)
Is Raytracing really needed on a tiny mobile device at say 300x400?
Easier for whom? (Score:2)
Scientific visualization (Score:2)
I came to browse Slashdot while waiting for some ray tracing of my own. I do atomistic modeling of nanomechanics and I'm rendering movies of how atoms wiggle and move during deformation. Here is a test shot of a 4 nm tall aluminum cylinder rendered at 150 femtoseconds per second of animation:
Aluminum nanocolumn vibration (Quicktime, 14 MB) [umich.edu]
It's amazing how nice ray tracing can look compared to other visualization methods. It took three hours to generate this 1000 frame movie. But as processors add
Where's the desktop version? (Score:3, Insightful)
If they want a phone to do 256 x 192 raytracing in real time, then a desktop with 1000x the compute power should easily be able to do 720x480 (full res television) in real time. But, oddly enough, there are no such titles out there....
Huh? (Score:2)