What does DX11 bring?

[taltamir]

AFAIK DX11 was supposed to bring forth tesselation and an MS proprietary competitor to openCL.
I know tesselation was delivered, but what of the MS SP compute? And was anything else improved/added by it?

 

[cbn]

AFAIK DX11 was supposed to bring forth tesselation and an MS proprietary competitor to openCL.
I know tesselation was delivered, but what of the MS SP compute? And was anything else improved/added by it?

Good question.

http://en.wikipedia.org/wiki/DirectCompute

In another search I found Nvidia making some comments, but nothing really original that couldn't have been found in the wikipedia link.

I hope someone else can find more info.

 

[Rifter]

untill we get faster cards it brings nothing as far as im concerned.

 

[hiddensniper11]

untill we get faster cards it brings nothing as far as im concerned.

Not only faster, it has to be more affordable as well.

 

[Rifter]

Not only faster, it has to be more affordable as well.

Also true!

 

[Throckmorton]

Stupid effects and crappy performance, just like DX10

 

[Scali]

AFAIK DX11 was supposed to bring forth tesselation and an MS proprietary competitor to openCL.
I know tesselation was delivered, but what of the MS SP compute? And was anything else improved/added by it?

DirectCompute is part of DX11, and supports most DX10 hardware aswell, like OpenCL.
But, like OpenCL, nobody has really used it for a major application yet. Both DirectCompute and OpenCL suffer from the problem that they're about 2 years late to the party, and Cuda didn't wait for them.

There are also some other improvements in DX11, but none of them are too dramatic. We got SM5.0, some new texture formats, and certain operations can now be multithreaded.

 

[Scali]

Stupid effects

A 3D API, be it Direct3D or OpenGL, does not 'do effects'. It just allows you to program your GPU, nothing more.
You have to program effects yourself, and how good or bad they are, depends on how well you program them.

 

[Sylvanas]

Metro2033's 'Depth of field' DX11 specific setting makes use of DirectCompute as is the only game to do so that I know of thus far. Unfortunately DoF tanks performance to ridiculous levels when enabled, this could say a few things, namely: a) DirectCompute is simply that taxing b) Drivers are poorly optimized for it c) Game is poorly coded for it. Considering Metro2033 was the poster boy for Fermi, I'd say Nvidia payed close attention when the devs were implementing it so I doubt it's poorly coded- IMO it's simply too demanding for today's GPU's even with Fermi's compute abilities.

 

[Scali]

Metro2033's 'Depth of field' DX11 specific setting makes use of DirectCompute as is the only game to do so that I know of thus far.

Now that you mention it, there are more games using DirectCompute for post-processing. Eg Alien vs Predator and Dirt 2.

a) DirectCompute is simply that taxing

Not DirectCompute itself, see my post above, regarding 3D APIs. It's up to the developer to implement things.
I suppose Metro2033 just uses a very heavy post-processing algorithm. That's not inherent to DirectCompute.

 

[Sylvanas]

Now that you mention it, there are more games using DirectCompute for post-processing. Eg Alien vs Predator and Dirt 2.



Not DirectCompute itself, see my post above, regarding 3D APIs. It's up to the developer to implement things.
I suppose Metro2033 just uses a very heavy post-processing algorithm. That's not inherent to DirectCompute.

Indeed, what you say makes sense- when a game performs poorly in Directx9 it's not Directx9's 'fault' it's only a means to an end and there are other examples that may look and perform better on the same API. As you say, same case with DirectCompute. Indeed so far it's only been used for post processing, why is this? Is it simpler and less tine consuming to implement these effects in DC than traditional methods (like an in house shader algorithm I assume). It'd be interesting to see things like Physics and AI implemented in Direct Compute and how it compares to what we have today.

 

[Scali]

Indeed so far it's only been used for post processing, why is this? Is it simpler and less tine consuming to implement these effects in DC than traditional methods (like an in house shader algorithm I assume).

I think it's a case of low-hanging fruit.
Post-processing is usually little more than a simple filter. Games had been using conventional shaders already, for HDR bloom, motion blur, depth-of-field and such... In fact, even without shaders, some of these effects can be implemented.
But with GPGPU instead of conventional graphics shaders, you have a bit more flexibility in memory addressing and such. So you can implement more advanced filters, or implement the same filters in less render passes, improving performance.

Physics is much more difficult to do. Most game developers don't even use their own physics code, they use third-party libraries instead (Havok, PhysX). ID Software and CryTek are the exceptions to the rule, but neither has announced support for GPU acceleration so far. So I don't think there's much of a chance that game developers write their own physics code for DirectCompute or OpenCL either.
And since Havok is owned by Intel and PhysX by nVidia, I don't see DirectCompute or OpenCL support coming from that direction either. Neither company has any reason to support it. Intel doesn't have any GPGPU hardware yet, and nVidia already has support through Cuda.

 

[Dribble]

DX11 like DX10 isn't going to bring a lot for now since:
a) hw not really fast enough yet - sure you can tessellate the odd thing, but none of the graphics cards out there can tessellate the whole scene which is what you'd need to really see the difference.
b) the consoles don't support it, hence DX11 is only used for some minor add ons to a DX9c game.

 

[Scali]

a) hw not really fast enough yet - sure you can tessellate the odd thing, but none of the graphics cards out there can tessellate the whole scene which is what you'd need to really see the difference.

I think it's mostly a case of most developers not knowing how they should be using tessellation properly.
I expect that the upcoming 3DMark will show them how it's done.

 

[dust]

I think it's mostly a case of most developers not knowing how they should be using tessellation properly.
I expect that the upcoming 3DMark will show them how it's done.

And only then we can play 3DMark finally!!

 

[nemesismk2]

deleted message because double post

 

[nemesismk2]

Stupid effects and crappy performance, just like DX10

That is what I think of DX10/DX11 as well. I can't think of a single game which looks amazing because of DX10/DX11?

 

[taltamir]

SM5.0, some new texture formats, and certain operations can now be multithreaded.

alright, what does SM5 bring to the table?
what do those new texture formats do? are they in any way better then old texture formats?
And how great a performance improvement is there from those multi-threaded new operations?

 

[Scali]

alright, what does SM5 bring to the table?

If you have to ask...
It's an instructionset, hard to explain what it brings to the table. Nothing spectacular anyway.

what do those new texture formats do? are they in any way better then old texture formats?

Some new types of compression, and some different arrangements. Basically it comes down to more efficient storage/better use of texture bandwidth.

And how great a performance improvement is there from those multi-threaded new operations?

It all depends on what you do with it. Basically you can now create objects in secondary threads while the main thread is rendering. But in most cases you want to avoid creating objects, so you don't gain much there.
The other multithreading feature is to create a list of rendering commands in a secondary thread. So while the main thread is rendering, you can already prepare the next renderpass. That reduces the CPU overhead during rendering to a minimum. But it depends on how high the CPU overhead was in the first place... usually pretty low.

 

[Lonyo]

http://www.anandtech.com/show/2716
Have fun.

 

[GotNoRice]

The best part of DirectX11 is that it is compatible with and is able to run directly on 10 and 10.1 hardware

It even has provisions that allow it to run on DirectX9 hardware, though most games still include a DX9 path due to compatibility with XP.

 

[Scali]

The best part of DirectX11 is that it is compatible with and is able to run directly on 10 and 10.1 hardware

It even has provisions that allow it to run on DirectX9 hardware, though most games still include a DX9 path due to compatibility with XP.

Yea I agree that's the best part. They should have had the DX9 downlevel from the introduction of DX10 aswell.
Could also have opened the door to a DX11 wrapper on XP (only supporting downlevel 9 obviously).

 

[nenforcer]

$300+ GPU's and no games that take advantage of it.

 

[taltamir]

$300+ GPU's and no games that take advantage of it.

you win the thread!
have an internet cookie.

 

[borisvodofsky]

DX11 is BS MARKETING hype... We're still stuck on dx9...

Fault the consoles really..

Watch the F-Bombs please.
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