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How Quake Wars Met the Ray Tracer
An anonymous reader writes "Intel released the article 'Quake Wars Gets Ray Traced' (PDF) which details the development efforts of the research team that applied a real-time ray tracer to Enemy Territory: Quake Wars. It describes the benefits and challenges of transparency textures with this rendering technology. Further insight is given into what special effects
are most costly. Examples of glass and a 3D water implementation are shown. The outlook hints into the area of freely programmable many-core processors, like Intel's upcoming Larrabee, that might be able to handle such a workload." We mentioned the ray-traced Quake Wars last in June; the PDF here delves into the implementation details, rather than just showing a demo, and explains what parts of the game give the most difficulty in going from rasterization to ray-tracing.
A Day in the Life of Debbie G1bs0n
A silver tear rolled down Debbie's perfect cheek as she slowly lowered her
sleek young body into the white marble bathtub. When she was younger, a nice
hot bubble bath was all she needed to raise her spirits, but now it seemed that
nothing would calm her troubled soul. Life wasn't easy for the teenage singing
sensation. It seemed that no matter what she did, no one would take her work
seriously.
"Trite," the critics had called her last album. "Trite, cheesy and
sappy." Debbie shuddered and began to weep harder. These were her innermost
feelings they were poking fun at. If "Lost in Your Eyes" and "No More Rhyme"
weren't heartfelt reflections of the depth of the human soul - she didn't know
what was. And surely "Electric Youth" was the most inspirational song about
youthful potential since David Bowie's "Changes." But still her finest works
were ridiculed by those too emotionally and intellectually immature to fully
understand them.
But Debbie's musical career wasn't what was bothering her, and she knew it
all too well. Her real problem was that she could no longer go on ignoring the
feelings that were swelling inside her body. She was blossoming into woman-
hood, but could not realize her fantasies in fear of tarnishing her image as
the fresh, innocent pop starlet. It wasn't so much to preserve her career -
she knew in her heart of hearts that she could make it on her talent alone -
but she felt she owed it to her fans. She wanted to be a role model to young
girls, to tell them that it's cool to just say no to sex and drugs - to follow
their dreams and to be individuals. But at the same time, Debbie was finding
it harder and harder to resist the powerful desires coursing through her veins.
Yes, Debbie was a virgin, but it was more by circumstance than conscious
choice. She was curious, but didn't want to just hop into bed with the first
guy that came along. And since her busy career prevented any kind of real
romance from developing, it seemed that she was doomed to chastity forever. It
had been months since the last time she had been touched in a sexual manner. A
smile crept across her face while her mind replayed once again that delicious
evening.
She washed the tears from her face while her slender toes slipped around
the tiny chain on the rubber stopper in the tub. A gentle tug and the water
began slowly draining away. Debbie began gently caressing her taut young body
as the water lowered, exposing her soft flesh to the cool air. Bubbles
crackled and popped on the delicate surfaces of her small, pert breasts -
sending tingling pleasures from her tiny pink nipples to her moist womanhood.
"Kirk," she whispered to herself. "Oh... Kirk...."
To most people, Kirk Camer0n was just another television star. He played
Michael on the popular sitcom "Growing Pains" - a winsome youth with an
irresistible smile and a keen wit. But he was more than this to Debbie. Much
more.
By now the water had reached the floating curls of her soft blonde pubic
hair. Debbie ran her slender fingers through the tiny locks and remembered
that night at the Emmys.
By mere chance they had been seated next to each other. They talked a
little, mostly about being mobbed by hordes of twelve year old fans whenever
they went out in public. But while they spoke, Debbie could feel Kirk
undressing her with his eyes - tracing her curves and taking obvious glances at
her tight skirt. He had an air of hungry confidence about him, and she felt
desires welling up inside her that she had never felt before. The lights went
down in the room, and the ceremony began. Kirk took Debbie's hand and began
gently stoking it. Then he suddenly let go, and instead put his hand on her
knee. Slowly he began to move it up her leg, stroking and caressing her inner
thigh; making Debbie swoon in shameful anticipation.
Lyin
It looks like raytracing will finally be a viable rendering method for games. It may be problematic because
Yeah, check dis out, this is O.G.L.B,
Knowhatimsayin? Im on my little O.G. Warren G -
And he just droppin this to let you B.G.'s know
Whas happen, y'all got to recognize
Cause this is y'know a Long Beach Thang -
21st street, but check this out,
G. gonna go out there, knoamsayin'?
And handle that shit now? yeah.
I was using a raytracer.
Interesting article. A little light on details. (What renderer were they using? OpenRT? Something they wrote themselves? Is it based on Kd-trees? BVH? BIH?) Also, not much mention of animation. Re-sorting the geometry whenever objects move is a hard thing to do efficiently, though there has been a lot of recent research in this area.
So when can I buy the CPU/Vid card that can do raytracing, heat my house, cook food off and pipe extra heat out for a steamhouse?
Be you Admins? nay, we are but lusers!
...between a raytracing demo and a slideshow?
Thank you Intel for not smooshing this informative summary into a bullet list PowerPoint.
Yet another ray tracing article and yet again all the same problems as before. Doing yesterday games in ray tracing is all nifty, but also kind of pointless. For one we already played them, but more importantly, it doesn't actually use the strength of ray tracing. Rendering a tree build out of texture quads is a nice accomplishment, but wasn't the whole point of ray tracing that one can have a million polygons and no longer need such hacks? So show me a realistic tree instead of trying to replicate the limitations of rasterization.
I am still waiting for a game/demo that actually is build from the ground up with ray tracing in mind and by that I mean one that actually looks good, just a few shiny spheres might have been impressive back on the Amiga some 20 years ago, not any more.
When looking at the before/after pictures, was anyone else surprised when they read which was the raytraced version?
To me, the ship in the water looks better with the bump map.
Seriously, as of a year ago I would rather have used an old AGP TNT2 than than the latest built in Intel graphics. I improved the performance of a relatives machine by 35% after putting in a PCI GeForce 5600 instead of using the built in Intel.
Did something happen over the past year or two that caused Intel to be able to publish papers like this? I mean their graphics are fine for a Windows desktop running Office and a browser, but it stops there unless something recently changed.
The preceding post was not a Slashvertisement.
There's a huge difference between the things they have in their lab and the things they're selling.
All of this stuff is done in software on the CPU, so the graphics hardware really doesn't affect it.
What? Not well-established? Raytracing is probably one of the most established graphics technologies. Specifically, it's been coming to games for years; only a matter of time. In fact, I don't really know why they're making such a big deal out of it here, since I'm pretty sure I read that the original quake (or was it doom?) traced a ray or two for some mapping reason, back when the source code was released.
Raytracing has mostly been replaced with other, faster technologies these days, which produce similar results, so it's not the panacea it seemed back when you had 5-bit hand-drawn stuff OR raytracing.
None of which is to belittle the work done on this game, because it does look nice, and improves on the graphics of the games before. But so do most games. Wake me up when town characters have emotions based on that guy you killed last week who rebuilt the clock tower because you suggested it back when you weren't so torn up about your wife dying.
guys they did this work, I played this game enough to be able to tell it wasn't fun to play, it tried to be a Battlefield 2 clone with a broken physics engine, and "real-time" shadows that wasted FPS and didn't need to be real-time at all, static objects could have just been baked into the megatextures like bf2, was sad to see ETQW when it finally showed up a year late and suck ass gameplay. Splash Damage and id should be ashamed of this product and tech.
Now on to the poor saps that had to add ray tracing on top of this poop in a box, you could show me another 500 images and I wouldn't be able to tell the difference.
Sorry fellas you can put a tuxedo on a turd but it's still a turd, maybe try again with Crytek 2 if they will let you have the source to work with at least you will have something that is state of the art to begin with, not a warmed over version of Doom3 / Quake 4 tech that was poorly coded by Splash.
Carmack is still turning in his grave, oh wait he still around? Oh yeah he is, ahh Mr. Carmack.. sir please stop working on console games and blow the world away again, we need you, and being a console whore is one more step toward mediocrity.
The problem with simulating reality is that reality is so incredibly BROADBAND. Every piece interacting with every other piece on every level from entangled subatomic particles to heat convection and induction to light reflections and .... wow! It's just an incredible experience, this reality thing!
Reality, by definition, is "dirty". We have dust, we have imperfections in every surface, no matter how carefully machined. Houses are never truly square, roads are never perfectly level, and points in a corner are always rounded. Always.
Computers, by definition, are "clean". Squares are always truly square, roads are as perfectly level as they were designed to be, and corners are always razor sharp, no matter how much you "zoom in".
The problem with modern graphics systems is they are computed to extreme levels of precision. If they incorporated a sort of fundamental randomness, if they were intrinsically uncertain, they just might be able to really approximate reality, which is messy, ugly, and imperfect.
Personally, I'd think that it really would take massive bandwidth, orders of magnitude beyond what we can produce today, and some pseudo-custom designed chips to get truly realistic graphics. Personally, I'm thinking about FPGAs which produce circuits at relatively low bandwidth but that are highly tuned to the task at hand. If there were a spec for FPGAs in video cards to handle specific physics handling tasks or ray-tracing, and there were a widely recognized spec for including this capability in a video card or somesuch, the problem of taking care of specialized processing problems could disappear tomorrow.
The other issue is bandwidth - and there's nothing to do about this except provide more of it. (Hypertransport, anyone? I have a 4-core Athlon Database server that outperforms an 8-core Xeon at 1.5x the "clock speed" simply by having more real, useful throughput....
I have no problem with your religion until you decide it's reason to deprive others of the truth.
they're looking into raytracing ''because'' they're graphic cards are so bad. They can't be bothered to juice up their video graphics department and productivity, so they're trying to make the world change, instead of Intel changing their ways.
- They would be a lot better off if they would just stop making graphics processors altogether and let ATI, Nvidia do the integrated graphics, or better yet, motherboard makers should bloody well realize that intel integrated is crap and stop buying integrated graphics from intel.
Hmmm, I WAS going to say that you should get yourself a better pc, but I think I've changed my mind and would recommend common sense, instead. No Shit intels lab work is going to be better than what the end user ends up seeing, usually because the end user is too dumb to set up a pc correctly, but maybe even a little bit because THEY USE STUFF YOU CANT BUY? sheesh, people these days.
Intel are perfectly capable of producing high performance graphics hardware. The reason they don't is that the cost of entry to that market is too high. ATI and nVidia have it sewn up between them. Intel make a lot more money selling lots of cheap chips to people who don't need much performance.
Is it just me or does this widely disseminated professional document contain a then/than error?
Let's hope that wasn't one of the coding challenges they faced.
if (x > y/2) than
{
'uh oh
}
(This post written assuming "the other one" = "the other part of the ray bundle")
Wolfenstein did "ray casting" - not the same thing.
No sig today...
As someone else noted, both pictures were raytraced.
To really show the difference between 2d and 3d water, you need to show the water interacting with a solid object close enough so that you can see that in one example the waves really go up and down and in another they're just a picture of waves on a mirror.
There's been a LOT of work making 2d water look dramatic, and I've seen people say they prefer 2d water in broad shots like this in other games (not even raytraced ones), but when you're in the game looking over the edge of a dock or looking at a nearby boat with the light behind you, it's pretty clear that spending more time on the physics of the water pays off.
Heck, even with 2d water, paying attention to the wave effects in shallow versus deep water pays off when you interact with it. And that's rarely done because it's not as dramatic.
They're still taking the wrong approach to raytracing. If Philip Slusallek was able to get 30 FPS in a raytraced game in 2005, using a single Pentium 4 behind a raytracing accelerator that was roughly equivalent to a Rage Pro in terms of gates and clock speed, it seems silly to me to ignore the possibilities of adding an "RPU" to the mix instead of just adding more general purpose CPU power. Yes, I know that's Intel's thing, but even for Intel... a raytracing core would be a tiny speck in an I7.
Our raytracing engine is the finest available! For all your sphere-on-chessboard game needs! If your game is going to involve spheres, chessboards, reflective spheres, or possibly spheres floating on water - raytracing is the way to go!
So was the ray-traced version of the game more fun? Or am I missing the point of games?
E pluribus unum
About half of the alike to reap to happeN. My your replies rather
Intel isn't trying to do ray tracing. Really, their point is to find a way to make GPUs unnecessary since it is a threat to the CPU market.
They can call it "ray tracing extensions" to the I7 or I8 CPU. It's not like the x86/x86_64 instruction sets are some kind of blushing virgin whose precious architectural purity would be violated by adding instructions like "RT_LOAD_MESH" and "RT_LOAD_SHADER"...
What bothers me is how nVidia is missing the boat.
Why is an article about a game that was released in mid 2007 tagged classicgames? Quake is a classic game, Enemy Territory: Quake Wars certainly isn't.
Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo!
Movie studios usually go with rasterization rather than ray-tracing because ray-tracers access scene memory in an unpredictable way, and so ray-tracing is excruciatingly slow if you can't fit the entire scene into the memory of one of the machines that's rendering it. Rasterizers can split the scene up, render the pieces separately, and combine the results in a single image.
For games, which typically run on a single machine, this is a non-issue.
Rasterizing triangles and the "first intersection" on a ray tracer actually give exactly the same result for a triangle mesh.
Ray tracing has a more obvious mapping onto the rendering equation, but rendering geometry or even first order reflections offers very little advantage (and several disadvantages) over rasterization techniques. Shadows are more implicit in ray tracing, but they don't look "better" until you have area light sources and start shooting a LOT of rays.
And that's really the problem. Most of the cool things you might want to do with ray tracing (soft shadows, photon mapping or other global illumination) involve shooting multiple-orders-of-magnitude more rays than simply drawing a game level.
If I had a fast hardware ray tracer, I'm sure I could find some very cool stuff to do with it, but wasting a ton of cycles doing what rasterization is perfectly adequate at is a bit pointless. It seems like a solution in search of a problem. If we could rasterize a scene normally, but do multiple raycasts in the pixel shader to determine light occlusion (shadows), we might be on the right track.
sig fault
About the ray tracing, but sure the game is a lot of fun . . .
The sad part is that they have had a PowerVR license for years but they have insisted on their abominable "Extreme Graphics" and GMA concoctions for PCs. PowerVR's approach (deferred tile-based rendering) is the most bandwidth economical out there (and fillrate and pixel shading economical but comparatively less so with the advanced Z-buffering optimizations of ATI and Nvidia during the past few years) so it would have been a perfect fit for integrated graphics. Their Series 5 design was DX9 compliant, no less. Sad that the story stopped at Series 3 Kyro cards, not counting their triumph in the embedded/mobile scene. Who knows what me might have now in PC northbridges. All in all, looks like a case of NIH syndrome, the PowerVR tech was certainly good enough.
Is 2009 finally the year of the real-time raytracing on the desktop?
I don't see fully ray-traced game engines being that big a deal in the future. It's a bit like in those early 3D movies having shit poked in your eye for WOW factor, going overboard with reflective surfaces in a fully raytraced 3D FPS would look like a mess. Look around you(tm), how many surfaces are fully reflective, how many of those reflect something recognizable? Answer: Very little... A simple static sphere map is perfectly sufficient to create the "illusion" of a reflective surface in most games. A separate thread could render a sphere map for any reflective surface in a scene on an as-needed basis for a scene. Or in real-time, creating a much more convincing raytracing effect without much overhead - as GTA IV does, for cars f'instance. As a bonus, you can do a more diffuse reflective mapping for surfaces like plastic. I think technology like Larabee will be much better used in game engines for accurate lighting models. Again, I simply point to GTA IV.
PowerVR is a fantastic technology (I used to work in STMicro's Graphics department with PowerVR so maybe I'm biased). The thing is, the STG 4500 (i.e. Kyro 2) was a pretty sizable chip. This means fewer chips to a wafer and so you can't make them quite as cheaply.
Kyro 2 was put against the low end GeForce chips. It was a decent chip capable of playing most modern games. So Why did STMicro closed their graphics division? Because they can't compete with the might of nVidia. Guillemot and Imagination Technologies were the only companies making boards. Guillemot because they were big enough to not to worry about upsetting nVidia, and Imagination Technologies because they're part the people who developed PowerVR.
Presumably Intel don't want any of this hassle. They make their chips as small and cheap as possible and sell them to companies that don't need a chip to do anything except draw some pixels.
The Kyro 3, had it ever gone into production, would have knocked the socks off the rivals.