AMD Mantle API [updating]

[ltcommander.data]

Yeah it makes you wonder why that wasn't always the delivery mechanism, as I asked earlier in the thread. My guess is - like with all big companies - differing teams/opinions internally. In any case, exposing stuff in GL is clearly a good path, so looking forward to seeing the extensions.

https://twitter.com/ID_AA_Carmack/status/386899206163554304

9x draw calls is credible over stock D3D, but Nvidia OpenGL extensions can give similar I mprocements.

John Carmack is reporting Mantle's 9x draw calls is already achievable on nVidia hardware with their OpenGL extensions. This makes it seem like ease of console porting is Mantle's primary differentiator.

 

[Dominik D]

I'm not an expert, but if you think about it, this may be a bit silly discussion. The way I understand it, AMD writes the drivers that implement the DirectX standards that Microsoft is basically only the curator of. So instead of talking to Its own DirectX compatible layer they can talk to mantle, which probably even shares a subset of the code for the DirectX HLSL implementation that AMD writes themselves, but with less overhead and more hardware specific features.

If Mantle is just an appendix to the DX (which I now believe it is) then most stuff would have to go through DX anyway, otherwise you wouldn't be able to use the necessary DirectX code in you application. DXGI/DXGK performs some validation so you've got to be a little bit sneaky about the stuff you do. But there's a way to introduce pixie dust into the shader for example - drivers can and do recognize shader bytecode provided by the DX to the UMD and sometimes instead of compiling it, push some super optimized version of the shader down the pipe. With the introduction of fcall one could rely on a simple preprocessor for the shader that switches new instructions into a meaningless but syntactically correct subroutines that are then replaces with Mantle-specific stuff in the driver. Basically the only requirement on the application/pipeline tool side would be to call some MantlePreprocessShader() before the D3DCompile() call.

 

[Blazkowicz]

Well, Cyrix for example didn't need Intel's blessing, but they had to do all the legwork to make a x86-compatible architecture from the ground-up, carefully avoiding specific patent-protected parts.
Of course, that was during the 80s and 90s. Now the technology is so much more complicated that square-one start up like that is a pure madness.

That must be why the 6x86 only supports i486 level for code, not i686 nor even i586 (I think). Maybe down to one little instruction missing. Of course people upgraded before that became an issue ; a small amount of people had a problem with it (such as doing a lightweight installation of a recent linux distro on old hardware)

 

[trinibwoy]

John Carmack is reporting Mantle's 9x draw calls is already achievable on nVidia hardware with their OpenGL extensions. This makes it seem like ease of console porting is Mantle's primary differentiator.

Well that and a spiffy marketing name like 'Mantle'

I don't know much about the DX pipeline to begin with but I'm not really clear how you use Mantle to bypass some aspects of DX while playing nice with others. I suppose AMD will manage buffers and other objects so that they're shared with pure DX when needed.

In the end if Mantle is simply a performance optimization for those devs willing to spend the time and effort then I say more power to AMD. It'll surely encourage Microsoft and/or nVidia to respond and tackle the inefficiencies that inspired Mantle in the first place and then everyone wins.

 

[Davros]

I was under the impression mantle was used instead of direct3d

 

[Brad Grenz]

From what we've been told it is, though I fear Anandtech's speculation that it is related to an Xbox One API has sown some confusion on the topic.

 

[Dominik D]

I was under the impression mantle was used instead of direct3d

Initially this seemed to be the case. But recent interviews seem to hint that it's a set of additional calls that one intertwined with DX calls (at least that's the impression I got).

 

[trinibwoy]

It would be cool if games exposed an option to switch between DirectX and Mantle like Unreal did back in the day with OpenGL. That way we can quantify the benefits first hand.

 

[Dominik D]

Battlefield will do that.

 

[elect]

I hear you, but we already have two mantle threads. And remember this is the "3D Architectures & Chips" sub-forum. Mantle (or other drivers, software, etc.) don't quite fall under this category. To be clear, I'm not saying we can't discuss mantle, but could we do it in one place in the right sub-forum? I don't feel like I'm asking a lot here...

From here on out, off-topic posts we be baleted. I'll try to move these posts to the right thread when I have more time (my break only lasts so long!).

Sorry, but which is the other thread you mean? This one?

http://beyond3d.com/showthread.php?t=64355&highlight=mantle

 

[willardjuice]

Sorry, but which is the other thread you mean? This one?

http://beyond3d.com/showthread.php?t=64355&highlight=mantle

Nope this one! Many posts (including the one you quoted) used to be in the VI arch thread; I moved them here. I suppose I should have deleted that one, but don't worry you're in the right place!

 

[Arwin]

Initially this seemed to be the case. But recent interviews seem to hint that it's a set of additional calls that one intertwined with DX calls (at least that's the impression I got).

No, I'm pretty sure that Mantle does not involve DirectX at all. The only confusion I've seen so far is from people that think the use of a certain shader coding format (HLSL) means that DirectX must be used somehow, but this is incorrect (many examples proving that).

I'm also pretty sure you'll see Mantle on Linux, without any DirectX.

 

[trinibwoy]

No, I'm pretty sure that Mantle does not involve DirectX at all. The only confusion I've seen so far is from people that think the use of a certain shader coding format (HLSL) means that DirectX must be used somehow, but this is incorrect (many examples proving that).

I'm also pretty sure you'll see Mantle on Linux, without any DirectX.

That would make more sense. So basically it's Glide with political support from PS4/XB1. Nice move from AMD to capitalize on the console wins.

 

[BRiT]

So basically it's Glide with political support from PS4/XB1.

I do not believe that to be the case.

 

[trinibwoy]

I do not believe that to be the case.

Metaphorically It wouldn't exist and couldn't survive if it wasn't for the fact that developers would be coding to a similar API on consoles anyway.

 

[xDxD]

The Xbox One graphics API is “Direct3D 11.x” and the Xbox One hardware provides a superset of Direct3D 11.2 functionality. Other graphics APIs such as OpenGL and AMD’s Mantle are not available on Xbox One

http://blogs.windows.com/windows/b/a...-direct3d.aspx

 

[DSC]

The Xbox One graphics API is “Direct3D 11.x” and the Xbox One hardware provides a superset of Direct3D 11.2 functionality. Other graphics APIs such as OpenGL and AMD’s Mantle are not available on Xbox One

http://blogs.windows.com/windows/b/a...-direct3d.aspx

Pretty much DEAD ON ARRIVAL and irrelevant.

 

[trinibwoy]

The Xbox One graphics API is “Direct3D 11.x” and the Xbox One hardware provides a superset of Direct3D 11.2 functionality. Other graphics APIs such as OpenGL and AMD’s Mantle are not available on Xbox One

http://blogs.windows.com/windows/b/a...-direct3d.aspx

Interesting. It's almost written as a rebuttal. They're claiming portability between Xbox One and PC but DICE obviously sees benefits in using Mantle over Direct3D on PC.

 

[xDxD]

Interesting. It's almost written as a rebuttal. They're claiming portability between Xbox One and PC but DICE obviously sees benefits in using Mantle over Direct3D on PC.

it is obvious that Microsoft can not see positively the emergence of any alternative to directx api which remains one of the reasons driving the sale of new versions of Windows. In addition, its use of directx much easier porting between Xbox1 and PC, indeed we may not speak more than porting almost ...

however:

 

[AlexV]

DICE obviously sees benefits in using Mantle over Direct3D on PC.

But they were helped to see as an organisation, and (one of) the architects for Mantle appears to be repi, Who is most passionate about this. If no repi and no shining..green...light from AMD, one wonders just how keen Dice would have been. I think the question now is whether or not AMD has enough batteries to shine their light in other huts, like that of Epic (will be harder though as NV has been quite adept at keeping Sweeney and Rein well lit). If they do, they might accrue some competitive benefits from Mantle, if not and all they have to show is people like all of the guys at their big "reveal" who weren't repi, meh, it will join the good company of CTM, Brook+ or Aparapi, to name but a few. I will admit (hello Willy!) that given their hand this was the best competitive move AMD could make.