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Students Evaluate Ray Tracing From Developers' Side
Vigile writes "Much has been said about ray tracing for gaming in recent weeks: luminaries like John Carmack, Cevat Yerli and NVIDIA's David Kirk have already placed their flags in the ground but what about developers that have actually worked on fully ray traced games? PC Perspective discusses the benefits and problems in art creation, programming and design on a ray traced game engine with a group of students working on two separate projects. These are not AAA-class titles but they do offer some great insights for anyone considering the ray tracing and rasterization debate."
Actually, yes ...
One of the main reasons that we now have 800 stream processors on fancy graphics cards is that you can split the most costly portions of advanced rasterization into hundreds of independant processes.
Instead of a video card you would just need a faster cpu, which if we base off of moore's law won't be much longer.
If the video card makers had picked up on the RPU you could use your video card to get realistic high frame-rate raytraced games today.
Dr Slusallek is working at nVidia now, so who knows?
To take Ziakll's argument even further... One problem with today's game industry is how long it takes to make a video game. Back in the 80s games could be made with a small handful of people in less than a year. Now it takes about 10 times as many people and anywhere from 2 to 5 years to produce a game. The biggest time (and of course money) sink in this process is art and level development. If raytracing can make things simpler and quicker to get accomplished for an artist then that will equal less time for production, and less development cost (maybe even cheaper games for the consumer in the long run). Real time raytracing is only inevatable just as it's only a matter of time till tools like Natural Motion's Endorphin and Euphoria take over the animation aspect. Any aspect of the development process that can be simplified or even better automated, will eventually win out.
;)
I'm betting that AMD's upcoming Hybrid chips will greatly benefit from Real Time Ray Tracing taking off. I'd just love to see someone come out with an open source RTRT engine that we could all start playing with right now, no matter how rudimentary
"A truly wise man realizes he knows nothing."
Simple example: Portal. Right now, it involves all sorts of crazy tricks. As I understand it, objects (at least, cubes which fall through the portal) are duplicated at both ends of a portal (in case you can see both ends at once)... The "hall of mirrors" effect of two portals across the hallway from each other is apparently intensive (it causes lag), and there is a hard (adjustable) limit, which can't be set above, what, 7 layers?
If Portal had been done raytraced, there would still be tricky things to do with the physics, but at least the portal graphics themselves would require roughly a single line of code -- add a few more, and you could have it shimmer and distort -- and they'd perform about the same either way. And they'd look better -- the "hall of mirrors" would continue to the pixel (or sub-pixel, if antialiased) scale, with no huge lag when you turn towards those mirrors.
But if there's one thing we could use in games, it's simplifying the code. Consider that games have tight schedules as it is (even moreso with the knowledge that any problems can be patched via download), and that it's not as though you have to design for ten years worth of feature enhancements and bugfixes -- you generally won't carry much over to the next game, so if it runs, it's good enough.
Given that attitude, what kind of hiring pratices will you have? Even The Daily WTF doesn't like to talk about it.
Now add the absolute requirement for performance, and you get esoteric, incomprehensible hacks at every level. And this is considered normal -- celebrated, even. After all, John Carmack has a hack named after him.
This is an area which could really use some solid engineering. To liken it to Web development, it seems everyone's working with crusty old PHP (or even straight C), when what's needed is either Rails (for large projects) or Sinatra (for small projects).
Don't thank God, thank a doctor!
The point is that, in raytracing, you can assign each of your 800 "stream processors" different pixels. Done. You're parallel. When one finishes, give it another pixel to work on, and repeat until you've rendered the whole thing.
Each core still has to iterate over all (well, some, I'm oversimplifying) of the triangles, but it can do so COMPLETELY INDEPENDENTLY of the other cores and still come up with a good result. Your performance gains are almost linearly proportional to the number of cores.
You can even have a relatively high-latency connection (Gigabit Ethernet, for instance) between the various cores, broadcast the scene data over this connection, and then receive individual "chunks" of rendered pixels back. I defy you to do that with rasterization.
-:sigma.SB
WARN
THERE IS ANOTHER SYSTEM
Just because CPU power is at the point where it may be enough, the whole point to having a video card is to offload that work to allow the CPU to deal with "more important" work. Console games tend to be very limited in terms of what is going on around the main character in a game. Sure, the graphics may be an issue, but you don't see games where the main character in a story has to push through a crowd of computer controlled NPCs that are not just there as a part of some puzzle, but are all doing or trying to do something.
Even on the PC side of things, a game like "The Witcher" really slows down when there are many NPCs in an area. If processor power isn't enough to handle a crowd of NPCs that don't have much of an agenda in a game, how do we have enough processing power to handle the game AI PLUS Ray Tracing?
If Ray Tracing is the goal, then yes, CPUs are at the point of being able to render a scene, but if you need that CPU to handle anything else, we have a long long long way to go before we have a powerful enough CPU plus GPU to handle it. This is why you won't see a move toward Ray Tracing any time soon.
In addition to this, the standards are still evolving as far as how to properly render things on a per-pixel basis. The current technology may use "tricks" that are not as good as ray tracing when you are talking high quality, but how long will it be before those tricks are so advanced that there won't be ANY difference to speak of? If Ray Tracing gives a 100 percent perfect rendering, and the tricks allow for something to get to 98 percent, how many people will really notice the difference?
I know fully well 3DSMax and Maya are the defacto standard in big shop game developers. Blender is HUGE among open source in indy game shops.
But the "other" underdog is TrueSpace. I've been with them (Caligari) since version 1. They're now at 7.6. In the almost 10-15 years they've been around they've always been under one guy, Roman Ormandi. It says a lot to me, that he hasn't yet "cashed" out on this amazing 3D hand changing that's been going on with all the other apps.
3DS started with Autodesk, went to Discreet and i think another owner, Autodesk realizing their mistake bought Maya, and then grabbed 3DSMax back. TrueSpace never had any foster parents the way these apps has, and because of that, has remained "pure" and uncorrupted.
It may be lacking in a lot of the technologies the other "big guys" have, but it stays pure to their path. The interface (though a lot more clunky than the past) remains clean and efficient to use. Unparalleled customization and tons of features I can't remember and have never used. They incorporated Python into it for scripting.
I could rave on like a Squirrel crossing the road about TrueSpace. I'll get back on focus now. TrueSpace is a true underdog in the 3D graphics field and IMHO underappreciated. I tip my hat to the team at Caligari.
To put it bluntly, at the moment the industry has to invest in better tools to simplify the asset creation stage.