Is AMD's tessellation still way behind Nvidia?

[Red Hawk]

Back when Nvidia premiered their Geforce 400 series, comparisons with the Radeon HD 5000 series was mixed, but one thing was clear: Nvidia was better at tessellation. Nvidia had a tessellator on each SM, allowing them to draw many more triangles per cycle on the Geforce GTX 480 than the Radeon HD 5870. AMD's approach had some advantages -- tessellation on Nvidia graphics cards scaled worse on the low end as they removed SMs, while low end AMD graphics cards were chugging along with mostly the same tessellator. But for the high end, Nvidia ruled tessellation.

AMD resolved to improve tessellation performance, and the first significant improvement came with the Radeon HD 6900 series. AMD decoupled geometry functions so that multiple geometry engines, including multiple tessellators, was possible. The 6900 series had two geometry engines, though theoretically AMD could add as many geometry engines as they had die space for. That wasn't enough to dethrone Nvidia, but it was certainly an improvement.

For the Radeon HD 7000 series, AMD brought the dual geometry engine design down to the mid-range 7800 graphics cards. However, they did not increase the amount of geometry engines on the 7900 cards, leaving both tiers with the same geometry engines. This had the odd effect of the higher clocked Radeon HD 7870 beating out the 7950 and even sometimes the 7970 at tessellation benchmarks.

I was browsing through some tessellation benchmarks on Anandtech, and AMD seems to be very competitive on the DirectX 11 Detail Tessellation benchmark:

http://www.anandtech.com/bench/GPU12/423

But you have to keep in mind that this benchmark was made for to test the first generation of DX11 graphics cards. It's not very stressful at all on either designer's modern high-end graphics cards.

Take a look at the tessellation-heavy Unigine Heaven benchmark and Anandtech's current tessellation benchmark, Tessmark:

http://www.anandtech.com/bench/GPU12/409

http://www.anandtech.com/bench/GPU13/596

AMD trails a bit behind in Unigine Heaven, and is way behind in Tessmark.

What do you guys think? Have AMD's tessellation improvements worked, or are the latter benchmarks accurate and AMD is still way behind? What do you think they should do to remedy that, if so? I think the obvious step -- and one I feel they should have made to the 7900 series -- is to simply add more geometry engines to the 9900 series.

 

[BallaTheFeared]

They're adequate for current games, but clearly still inferior.

Though they've come a long ways since 5xxx series.

You have to wonder as a Radeon owner how much performance you're giving up in some of these tessellated games.

To give you an idea, load up Heaven, then use the slider to change the amount of tessellation present. Moving the bar from none to the next setting causes a decent loss in FPS, if AMD had a better tessellation engine my guess is this hit would be less dramatic.

That said we still have very few games that have a lot of Tessellation, Crysis 2 and Crysis 3 are still the King's for this feature as far as real world goes as far as I know.


This time around is more even, last time 5xxx series was simply awful with tess and 6xxx did little to close that gap. However unlike last time there is also the Compute aspect, AMD seems to have the upper hand in things like Lighting and DOF when using the DX11 compute shaders.

I think this gen AMD had the better uarch, Kepler is still Fermi. However Fermi is still a monster, and GK110 can pretty much out muscle AMD on just about every front due to simply brute force power and walk away where they're stronger.

 

[Silverforce11]

To be fair Balla, point 1) tessellation is poorly used in recent games, good usage doesn't need excessive implementation (certainly not on flat surfaces or invisible elements). point 2) GK110 can out muscle because it is a monster die in comparison.

Tessellation adds to the game when its used to make characters more fluid and less angular, or obvious items such as wheels, cogs, circular objects. That's the more obvious IQ resulting in its usage. Roads like in Unigine is fugly.

 

[boxleitnerb]

But the stonewalls are not. I don't care so much for subtle improvements, I want detail that is immediately visible. Roofs, masonry, statues, organic characters like dragons or aliens...

 

[Carfax83]

To be fair Balla, point 1) tessellation is poorly used in recent games, good usage doesn't need excessive implementation (certainly not on flat surfaces or invisible elements).

A not so subtle dig at Crysis 2. Anyway, it's known that the invisible body of tessellated water in Crysis 2 was culled from rendering, so lets not bring that up shall we?

As for flat surfaces, you have a bit of a point I agree, but at the same time, the whole idea of tessellation is to add extra detail to objects of all kinds. Flat surfaces can definitely benefit from being tessellated, and it's not just a waste.

Crysis 3 uses a lot of tessellation, but in a more conservative way and the effects are more subtle than in Crysis 2. I'm sure that since Crysis 3 was a G.E title, AMD made sure they didn't use an abundance of tessellation that would put their GPUs in a poor light.

Tessellation adds to the game when its used to make characters more fluid and less angular, or obvious items such as wheels, cogs, circular objects. That's the more obvious IQ resulting in its usage. Roads like in Unigine is fugly.

One game that has impressive use of tessellation to me is Metro Last Light. Practically all of the main characters, NPCs and monsters are tessellated to some degree. Plus it's on a lot of inorganic surfaces as well.

 

[zlatan]

That said we still have very few games that have a lot of Tessellation, Crysis 2 and Crysis 3 are still the King's for this feature as far as real world goes as far as I know.

Actually Tomb Raider is the "king of tessellation" now. The engine use this feature on every single surface in the game.

 

[Arzachel]

A not so subtle dig at Crysis 2. Anyway, it's known that the invisible body of tessellated water in Crysis 2 was culled from rendering, so lets not bring that up shall we?

Everybody knows the sky is green so lets not bring the up, shall we? (forum.beyond3d.com/showpost.php?p=1703583&postcount=4270)

I find tessellation of random background scenery incredibly wasteful. I'd much rather see the performance budget go towards better lightning, more detailed character models and a denser environment instead of a brick wall with perfectly rendered errosion patterns. As long as there is a vocal minority that cares more about the fps counter going down than the actually perceivable image quality, it makes sense to have a setting that makes the pavement slightly prettier while halving the framerate, I guess.

 

[sontin]

A flat wall can't give you better lightning and shadow effects because it is flat. The difference in Crysis 2 between the walls with and without Tessellation is mindblowing.

 

[boxleitnerb]

Halving framerate? Right...if you don't go nuts on tessellation factors, performance is a minor concern.

 

[OatisCampbell]

I don't think it matters. Very happy with gaming on my 7970, if I'm "missing out" on tessellation, haven't noticed.

I did play Crysis 2 without tessellation, my mind was not "blown".

 

[Unoid]

My Radeon 8500 kicked tessellation ass in Return to Castle Wolfenstein...
that was back in 2001?

 

[Red Hawk]

This time around is more even, last time 5xxx series was simply awful with tess and 6xxx did little to close that gap. However unlike last time there is also the Compute aspect, AMD seems to have the upper hand in things like Lighting and DOF when using the DX11 compute shaders.

I'd say that the 6000 series was more of a leap forward in tessellation on the high end than the 7000 series, since the 6900 cards actually doubled the geometry engine over the 5800 cards while the 7900 cards kept much the same geometry engine as the 6900 cards, only more fine tuning and tweaking it.

Actually Tomb Raider is the "king of tessellation" now. The engine use this feature on every single surface in the game.

I wouldn't say Tomb Raider is the "king of tessellation"; they certainly make good use of tessellation though, applying it both to the environment and to characters. I don't think they use it on "every single surface of the game", though.

Everybody knows the sky is green so lets not bring the up, shall we? (forum.beyond3d.com/showpost.php?p=1703583&postcount=4270)

I find tessellation of random background scenery incredibly wasteful. I'd much rather see the performance budget go towards better lightning, more detailed character models and a denser environment instead of a brick wall with perfectly rendered errosion patterns. As long as there is a vocal minority that cares more about the fps counter going down than the actually perceivable image quality, it makes sense to have a setting that makes the pavement slightly prettier while halving the framerate, I guess.

Tessellation uses a specific fixed function component of the GPU, so you wouldn't get better lighting performance simply for cutting back on tessellation.

 

[RussianSensation]

I'd say that the 6000 series was more of a leap forward in tessellation on the high end than the 7000 series, since the 6900 cards actually doubled the geometry engine over the 5800 cards while the 7900 cards kept much the same geometry engine as the 6900 cards, only more fine tuning and tweaking it.

7970 is a way bigger leap in tessellation than 6970 was over 5870.

Here is 6970 vs. 5870:

Here is 7970 vs. 6970:

NV is still way faster.

 

[Red Hawk]

7970 is a way bigger leap in tessellation than 6970 was over 5870.

Here is 6970 vs. 5870:


Here is 7970 vs. 6970:


NV is still way faster.

Ah, my mistake then. I guess the 6970 laid the ground work for improved tessellation performance, while the 7970 refined and perfected how AMD was doing it. Still, I think the next logical step is to follow up on the promise that AMD can increase the number of geometry engines at will.

 

[lavaheadache]

at what point does it matter how good the tessellation performance is? Nvidia's implementation at this point seems to be mostly wasted

 

[bystander36]

at what point does it matter how good the tessellation performance is? Nvidia's implementation at this point seems to be mostly wasted

Nvidia's tessellation engine is different. Their Polymorph cores transform into a tessellation engine, but if tessellation isn't used, they are used used in other ways (at least this is how I've read it). I don't know all the specifics on how this all works, but it allows for great flexibility without a lot of wasted hardware.

At least this was how Fermi did it, and I assume they haven't changed.

 

[futurefields]

List of games that use tessellation?

And what is tessallation mostly used for? To me it sounds like bump mapping, but we've had that in videogames for over a decade now.

 

[Red Hawk]

at what point does it matter how good the tessellation performance is? Nvidia's implementation at this point seems to be mostly wasted

When games are made to use it. We'll probably see more once the Xbox One and PS4 launch. We may not see full usage of Nvidia's tessellation though, since the PS4 and XB1 are using AMD GPUs.

 

[Carfax83]

When games are made to use it. We'll probably see more once the Xbox One and PS4 launch. We may not see full usage of Nvidia's tessellation though, since the PS4 and XB1 are using AMD GPUs.

Since tessellation is scalable, I'm sure we'll see some TWIMTBP games really kicking it up a few notches in the future. Watch Dogs in particular will be the one to watch I think, as that's going to be the first next gen single player experience this year.

E3 2012 had a preview that ran on a GTX 680, and it looked wonderful. That was on old code, so I'm sure it will look even better on release..

 

[sontin]

List of games that use tessellation?

And what is tessallation mostly used for? To me it sounds like bump mapping, but we've had that in videogames for over a decade now.

Bump Mapping or POM are emulating "real geometry". Tessellation creates new vertics or triangles. We dont want POM, we want real geometry.

 

[el etro]

One game that has impressive use of tessellation to me is Metro Last Light. Practically all of the main characters, NPCs and monsters are tessellated to some degree. Plus it's on a lot of inorganic surfaces as well.

Impressive is that Radeons can still do well against Geforces in this game, even with max tesselation.

 

[itsmydamnation]

Bump Mapping or POM are emulating "real geometry". Tessellation creates new vertics or triangles. We dont want POM, we want real geometry.

then you dont really want tessellation either, at the end of the day tessellation is nothing more then a form of compression. that compression has limitations, just in the same way POM has limitations. Its about choosing the right tool for the job, the right tool being which gives the effect i what that is cheapest/most efficient to implement.

small Triangle sizes have impacts on other parts of the pipeline.

 

[ocre]

then you dont really want tessellation either, at the end of the day tessellation is nothing more then a form of compression. that compression has limitations, just in the same way POM has limitations. Its about choosing the right tool for the job, the right tool being which gives the effect i what that is cheapest/most efficient to implement.

small Triangle sizes have impacts on other parts of the pipeline.

i cannot agree that tessellation is a form of compression. I think your looking at it completely the wrong way.

 

[ocre]

I am excited about the future and the changes that will be soon coming. Next gen consoles will surely bring us better implementations with games built from the ground up with tessellation in mind. Not just a bolt on after the fact. I cannot wait to see games evolve again. We have been stuck in this box for so long now and it has become dull. Progression has slowed down so much and the new consoles should jump start new life into gaming as we know it.

I dont expect things to start off much different when they first launch. Most of the major titles coming out will be available on last gen hardware/ designed for last gen hardware with bolt on/add on features. But as the new consoles start taking root, the advancements should be unmistakable.

As for the OP, its not gonna make much a difference. I believe by the time tessellation and the new consoles make an impact, AMD will be caught up with (or surpass) nvidia in their tessellation capabilities

 

[Carfax83]

Impressive is that Radeons can still do well against Geforces in this game, even with max tesselation.

That's because the tessellation isn't extensive enough for there to be a major difference. No game really employs tessellation to that degree yet. In synthetic benchmarks or benchmarks like Heaven 4.0, the difference is a lot more substantial because tessellation is so much more pervasive.