Tessellation

[Mr McC]

Tesselation, it seems to be everybody's favourite new word, but what implications does it have?

I expect that we'll be hearing more and more about tesselation over coming months. This can in part be attributed to Fermi's superior tesselation performance: Nvidia, if and when they finally get sufficient stocks of 480's and 470's on to shop shelves, will undoubtedly put a lot of effort into spinning an area where they have a clear advantage.

However, will this translate into an increased number of games that make use of this capacity? Can we expect to see more and more titles that are optimised to take advantage of one of Fermi's strongest selling points? Will such optimisation take place on a level playing field, or can we expect to see something along the lines of the disabled in-game AA for Ati cards present in the Arkham Asylum title? To take Metro 2033 as an example, a TWIMTBP game, the increased tesselation capacity of the 480 isn't really showing much in game advantage.

I have no doubt that Southern Islands will improve tesselation capacity; however, whether that is simply to take the title away from Nvidia or whether we, as consumers, will see a tangible improvement in the near future remains to be seen.

More importantly, should anyone considering upgrading to a 5850 or a 5870 be concerned about the tesselation performance of either card? Is Fermi that much better and does it matter?

 

[D007]

If you've ever worked in 3d max or 3d software you might be familiar with tesselation.
It really ups the quality of pictures and the polygon count. I can see how tesselation alone could require the implementation of entirely new game engines as it would be to high of a poly count for quite a few existing engines to even use without crashing.
It's going to increase depth of pictures and quality by a very noticeable amount.
For example where you use to see bitmapping for facial wrinkles you might now actually see the depth in those wrinkles.
Not only that, but the quality of all curves can be enhanced with tesselation.
Been a little while since I played with it, but I "think" that's the gist of it.

 

[cadaveca]

Tesselation should be used to allow for less data being sent from CPU to GPU. The tesselator should be adding the extra triangle detail @ the gpu only.

But, currently, it's jsut an add-on feature, much like Phys-X. So I'm not overly concerned about it...maybe next years games might use it right.

 

[xBruce88x]

yea that sums it up right there... for a good look watch this vid.

http://www.youtube.com/watch?v=9ABeq7PEdRc

 

[bobzilla2009]

To be honest, unless a game is a TWIMTBP game that is determined to use as much tessellation as possible or just a benchmark (like heaven), i don't think any implementation of tessellation will make the higher end hd5 series cards choke for at least 2-3 years. By that point we'll probably be moving onto whatever generation is out then.

However i do hope tessellation does get used, even in small amounts to keep anything above a hd5750 from struggling. They could always have tessellation settings too, like i think there should be to keep scalability with lower end dx11 cards.

 

[D007]

Tessellation is not something that is going to go away IMO.
It's already and integrated part of most 3d design products.
I think it can only get better.

 

[Mr McC]

Tessellation is not something that is going to go away IMO.
It's already and integrated part of most 3d design products.
I think it can only get better.

I agree, but how soon before it becomes adopted in games? I assume that they will continue to produce DirectX 9 games for the foreseeable future and simply add in a few highlights or smoke whirls via DirectX 10 & 11. I don't think they fully tapped the possibilities of Direct 10, and yet now, stopping off at 10.1 along the way, we're on to 11: will it pass in the same discreet fashion before we suddenly have DirectX 12 thrust upon us? We may have to wait for the consoles to upgrade to the next generation before we see the full possibilties of DirectX 11 come to the fore.

If that all sounds a bit negative, it is not intended as an attempt to downplay tesselation and what it implies. I'm just a bit sceptical of its real world implementation in the near future and I'm concerned about whether or not I'd be better off waiting for Southern Islands (I think we all assume it will improve tesselation performance) before I buy my next card.

 

[D007]

Not at all negative, more like "realistic" I'd say lol..
We jumped from dx9 to dx 11 way to fast, no telling what will happen.
I have personally added tesselation to items in 3ds though and it's very nice.
It's just not to difficult I think. Their not building that architecture from the ground up like right now. It already has a strong foundation, just need game engines to support it.

I don't think it would hurt at all to wait for the next line of gpu's though.
Like you said, it may very well take some time. I just don't think it will take that long because tesselation has been around for a while already, they just didn't support it except for high end cgi type rendering.

 

[erocker]

Layman's terms: Tessellation helps to make graphics look better. Instead of an octagonal hole, it's round, instead of a somewhat pointed and angular army helmet is is smooth and round.

 

[cadaveca]

Many don't realize, either, that ATi has had tesselation since 2001. They've been doing it for far longer than nV has. Here's the press release:

Tuesday May 29, 2001

--------------------------------------------------------------------------------
MARKHAM, Ontario – ATI Technologies Inc. (TSE: ATY, NASDAQ: ATYT), a world leader in graphics, video and multimedia solutions, today unveiled TruForm™, a new rendering technology developed for future generations of graphics processors that will help to deliver the smoothest, most natural 3D images ever seen on both existing and next-generation 3D games and personal computers.

“Despite recent improvements in the graphical quality of computer games, for example, most 3D objects – especially characters – still do not appear very lifelike,” said Toshi Okumura, Senior Product Manager, Desktop Marketing, ATI Technologies Inc. “They still tend to look like a collection of geometric blocks with textures painted on them, largely because of limited bus and memory bandwidth.

“Without compromising the overall performance of current PC technologies or compatibility with existing 3D games, TruForm breaks through these challenges to deliver the smoothest and most natural images ever seen on a PC.”

By employing N-Patches (also known as PN Triangles) – a new type of higher order surface composed of curved rather than flat triangles that was developed by ATI and is supported in Microsoft’s DirectX™ 8.0 and OpenGL™ technologies -- TruForm permits surfaces to be generated entirely within the graphics processor, without requiring significant changes to existing 3D artwork that is composed of flat triangles. This ensures that the technology is easy for software developers to implement and avoids breaking compatibility with older graphics processors, while still delivering the best visual experience to owners of newer graphics processors that support TruForm. As a result, N-Patches offer the most efficient and practical higher order surface implementation.

“TruForm also allows for a higher level of scalability, meaning the number of triangles or polygons in a 3D image can be varied according to the capabilities of the installed graphics hardware,” explained Mr. Okumura. “Software developers usually create low triangle count models so that their games can run well on low-end PCs, which make up the vast majority of products used today by consumers.

“TruForm can take these 3D models with low polygon counts and generate smooth, highly detailed images, affording most users a greatly enhanced visual experience with no compromise in performance or compatibility.”

TruForm effectively amplifies geometric information, thereby enabling more visual detail while sending a smaller amount of data across the AGP (accelerated graphics port) bus, and affording a savings in graphics memory usage.

Further, TruForm helps to overcome the increased bandwidth and memory requirements associated with having to transfer and store large numbers of triangles or polygons – the geometric basis of computerized 3D images. As more detailed and realistic 3D images are created, the number of polygons required to represent each image increases at a dramatic rate. TruForm effectively increases the memory bandwidth available to the GPU (graphics processing unit) by converting 3D images with low polygon counts to smoother, high polygon count versions in the graphics chip, a process known as tessellation.

Finally, TruForm uses advanced N-Patch lighting techniques to provide 3D objects with highly detailed lighting effects. This greatly enhances the visual quality of images by providing realistic highlights on the surfaces of curved objects.

http://ati.amd.com/companyinfo/press/2001/4377.html


This is why I was so puzzled by nVidia hyping Tesselation so much...ATi will stomp them...when it's needed. Even the 360 has tesselation. It's why I'm so sorely disappointed in the tech as it stands right now...it's nothing new to developers, and if it is, they need to go back to school.

We're talking Radeon 8500 tech. 10 years old. I don't see what all the fuss is about.

 

[D007]

Marketing at it's best, at it's worst..lol.. Thing is tesselation causes such a high poly count that it would crash most game engines without a second glance.
It's not new or groundbreaking in terms of what exists in the development field but it will be groundbreaking when you actually start to see it in games.
It has never been implemented in anything other than extremely high def CGI type rendering before that I'm aware of. It's mostly just been industrial and cinematography useage.
It's a huge step towards making games look even more real.
Check out that youtube footage ^^.

 

[cadaveca]

Great. Seen Unigine on my own system, and it looks really bad, IMHO, like stuff from 3DMark2005, but poorly coded so as to create a massive workload. Textures were designed specifically so create huge tesselation workloads, and @ FPS noone will settle for...whoo-hoo!:shadedshu



"Oh look, we can do stuff from 10 years ago...today! And we are the best at it!"

LOL. nVidia doesn't realize how silly they actually look. Took them 10 years to agree with a spec for DirectX(a spec that makes previous tesselators useless), and now we are supposed to get excited?

It's like Jen Hsun saying "We made Phys-X!"

Uh, no you didn't dude..you merely made it suck.

 

[erocker]

When Nvidia was runing that v1.1 Heaven demo, I knew they got their fingers (possibly wallets) involved with Uningine. Fermi uses two tessellators, 5 series has one. There are currently no games that brings either card to its knees due to tessellation, and we'll see new ATi cards with better tessellation this year yet. Right now, honestly tessellation doesn't really matter much.

 

[D007]

When Nvidia was runing that v1.1 Heaven demo, I knew they got their fingers (possibly wallets) involved with Uningine. Fermi uses two tessellators, 5 series has one. There are currently no games that brings either card to its knees due to tessellation, and we'll see new ATi cards with better tessellation this year yet. Right now, honestly tessellation doesn't really matter much.

Nope, it doesn't, like doesn't matter at all as of yet. Kind of like dx 11..lol

 

[Zubasa]

yea that sums it up right there... for a good look watch this vid.

http://www.youtube.com/watch?v=9ABeq7PEdRc

Never liked that Unigine Heaven thing .
Tessellation is suppose to add more details at lower cost, not to make dragons look like star-fishes and slaughter performance. :shadedshu
And yes the performance sucks even for the GTX 480.

Set tessellation on moderate and you get a much more realistic idea of how things are supposed to look.
But that still doesn't fix the problem with spikes popping out of no where when you close in on the dragon,
because Heaven is simply over-done (but not properly) in Tessellation

 

[erocker]

Nope, it doesn't, like doesn't matter at all as of yet. Kind of like dx 11..lol

I love DX11. BC2, Dirt 2, Metro 2033 all look superior with DX11. Crysis 2 is almost here too. I look forward to more DX11 titles.

 

[cadaveca]

DX11 isn't just about tesselation though. In fact, as you can see in the press release above, even DirectX8 had support for tesselation.

It's pure media hype from the green team that have things construed as such. DirectX has nothing to do with tesselation finally being used...it's finally being used now that both nV and ATi have hardware to support it.

I haven't seen a good implementation of Tesselation yet. Not one. Yes, DX11 seems to allow for much better colours, and some performance improvements, but good coding could have done all of those things WITHOUT DirectX11. With proper tesselation, there'd be no need for AA @ 2560x1600, yet I still find myself enabling it for each and every app on the market today.

People are complaining that the PS3 is hard to code for...you really cannot expect much from these people.

 

[erocker]

People are complaining that the PS3 is hard to code for...you really cannot expect much from these people.

Lol, inferior GPU with a superior CPU. If it don't work on the GPU, just offload it to one of the processing cores... Oh yeah, sounds easy... It just doesn't work..

 

[cadaveca]

It's really no different than running Phys-X. It's called deffered rendering, and isn't new either...it's just more work. It's easier to do it differently, and that, to me, just speaks volumes of lazyness. Innovation doesn't happen by taking the easy route...if they were doing the grunt work now, the future would be so much easier.

I mean, yes, the PS3 is not ideal...but the gpu is more than adequate for 1280x720. It can run 1080p too...not very well, but 30FPS is more than possible.

That all said, the PS3 is highly dated. So is the 360. It wouldn't be a big deal..but guys are literally whining about the PS3. Whining. Making excuses. Instead of working.

Nobody is gonna use DX11 right until they start thinking outside the box. And nobody will do that until all the legacy hardware is gone.

Dx9 is the legacy now, so we're stuck with it. Maybe in 5-6 years DX11 will be used right. It's been 10 years, and still, Tesselation is an add-on. GPU-Physics are add-ons. They need to be integral parts, and cannot, with DX9 hardware.

 

[Mr McC]

It's really no different than running Phys-X. It's called deffered rendering, and isn't new either...it's just more work. It's easier to do it differently, and that, to me, just speaks volumes of lazyness. Innovation doesn't happen by taking the easy route...if they were doing the grunt work now, the future would be so much easier.

I mean, yes, the PS3 is not ideal...but the gpu is more than adequate for 1280x720. It can run 1080p too...not very well, but 30FPS is more than possible.

That all said, the PS3 is highly dated. So is the 360. It wouldn't be a big deal..but guys are literally whining about the PS3. Whining. Making excuses. Instead of working.

Nobody is gonna use DX11 right until they start thinking outside the box. And nobody will do that until all the legacy hardware is gone.

Dx9 is the legacy now, so we're stuck with it. Maybe in 5-6 years DX11 will be used right. It's been 10 years, and still, Tesselation is an add-on. GPU-Physics are add-ons. They need to be integral parts, and cannot, with DX9 hardware.

Regretfully, that seems like a very fair and well founded appraisal.

 

[HalfAHertz]

Many don't realize, either, that ATi has had tesselation since 2001. They've been doing it for far longer than nV has. Here's the press release:



http://ati.amd.com/companyinfo/press/2001/4377.html


This is why I was so puzzled by nVidia hyping Tesselation so much...ATi will stomp them...when it's needed. Even the 360 has tesselation. It's why I'm so sorely disappointed in the tech as it stands right now...it's nothing new to developers, and if it is, they need to go back to school.

We're talking Radeon 8500 tech. 10 years old. I don't see what all the fuss is about.

Heh, not only that but to further add salt in the wound, ATi had a "GPU phisics" implementation since Radeon 9700 called R2VB
http://www.behardware.com/articles/616-3/ati-s-demos-without-vertex-texturing.html

 

[the54thvoid]

Late into this topic but the extreme tesselation on unigine 2.0 is absurd. It makes what should be even but separate cobbles unrealistically rounded. I'd have to kill that street planner. The roof tiles become 1 foot thick. I'd sack that roofer. And yes, the dragon becomes a freaking porcupine. Quick, call Darwin.

Tesselation adds nice effects to otherwise flat features (red brick walls in stalker COP are a great example) but cranking it up to prove a gfx cards power is showboating a rather one dimensional ability.
Heres my equation for the situation:

[Great gfx + moderate gameplay] < [Moderate gfx + great gameplay]

 

[newconroer]

I would have thought Wile might have dropped some comments, he had a good summary of it sometime last year.

The main thing we were looking for, is how it allows the GPU to take more overhead and compute things that the CPU normally would. Particularly objects on screen such as flora, trees, characters etc. It can make and clone objects at a considerably higher rate, and with more density, thus taking the strain off of the CPU.
A good example is MMO games. You have vast lands with long view distances and all kinds of geometric and character related objects. If you could remove a lot of those from the display, you would see possibly a dramatic increase in frame rates. Theoretically speaking, tessellation should allow the GPU to manage that, thus not impacting the frame rates and giving the performance as if the objects were not even on screen.

However while tessellation is the poster boy for DX11, so far it doesn't seem it's being used as we were all led to believe it would.

A lot of the tech demos show how tessellation allows for increased polygon count, and therefore smoother images. Particularly with circular objects. However a lot of that is very hard to notice, especially while in motion.

So the complaint is that -like with DX10 features- it's cool, but not entirely necessary.

I am keen to see when they start making use of it's ability to free up the CPU from unnecessary strain, and help remove it as a weak link in the chain.

Technically, tessellation should (in a pseudo fashion at least) be the thing that breaks the a-typical CPU>GPU constraints that we have with modern architecture. But so far, none of the games that use it, have actually done this where it counts.

 

[twistedneck]

I would have thought Wile might have dropped some comments, he had a good summary of it sometime last year.

The main thing we were looking for, is how it allows the GPU to take more overhead and compute things that the CPU normally would. Particularly objects on screen such as flora, trees, characters etc. It can make and clone objects at a considerably higher rate, and with more density, thus taking the strain off of the CPU.

-Snipped

newconroer, if its designed to remove work from the processor then its not doing much improvment. even in Unigine or Metro 2033, the processor never gets used over 30-50%, and the cpu is just getting stronger by the year. If its an issue with delay due to a conversation between cpu and graphics, i get that.. but i can even see that bottle neck going away with faster pci systems in coming year or two.. but maybe they wont be quite as fast as a gpu doing it directly from a map.