"Bringing DirectX 10 to Xbox 360"

[Acert93]

If the Xbox could handle PC SM 3.0 native the answer from Paul Bleisch should be different. In this case he had written SM 2.0, SM 3.0 and a specific SM 3.0 variation.

On Windows, we expose support for all existing D3D9 shader models (SM1.1 through SM3.0). On Xbox you'll get SM2.0 and the Xbox 360-specific SM 3.0 variation ("XVS 3.0" and "XPS 3.0"). Neither Xbox 360 or Windows supports SM 4.0 which is D3D10.
Paul

From ATI and MS in the past we have heard a number of comments about "SM3.0 +". Now that very well may be PR, but if you refer to my post earlier in the thread, which links to the Xenos article, it actually goes to some length comparing PC SM3.0 requirements and what Xenos supports, and in almost every case Xenos supports more than SM3.0 requires. There are also a number of texture formats that may exceed D3D10 standards and of course with unified shaders Xenos and point sampling things like vertex texturing (not completely required if you can do R2VB) are natively supported.

So my question to you: How do you arrive at the following conclusion based on Paul's quote:

Locks like that Xenos is not able to process PC SM3 without problems.

Do you have another source or are you assuming "Xbox 360-specific SM 3.0 variation" means, "Cannot do what the PC can do"?

If it is the later, I would venture a guess that the fact Xenos can do hardware tesselation, memexport, and a number of things not in the SM3.0 featureset that the Xbox 360-specific variation is a version of the API / Shader Model that supports these features NOT found on the PC.

 

[Demirug]

I am sure that the XBox 360 SM3.0 variant has some features that the PC SM3 don’t have. But there must at least one missing thing that holds them back to support native PC SM3 with XNA on the XBox 360. I could not they general infrastructure as SM2 is supported. Anyway there are only a few days left until they release the first beta of XNA. Maybe it already contains information’s about the differences between PC and XBox SM 3.

 

[Shifty Geezer]

But there must at least one missing thing that holds them back to support native PC SM3 with XNA on the XBox 360.

Why? It's possible to have a varient that is more than the original, can do everything the original can do, but is different. Because there's no such things as SM3.0+, and there's only SM3.0 and SM4.0, to talk about the customized SM3.0 model the guy referred to it as the 'specific variation'. This variation may cover slightly different API calls, but feature wise I can't see anything preventing PC SM3.0 being run.

 

[Demirug]

Why? It's possible to have a varient that is more than the original, can do everything the original can do, but is different. Because there's no such things as SM3.0+, and there's only SM3.0 and SM4.0, to talk about the customized SM3.0 model the guy referred to it as the 'specific variation'. This variation may cover slightly different API calls, but feature wise I can't see anything preventing PC SM3.0 being run.

If there is no feature missing why it isn’t supported? The XNA framework should be the great unification of PC and XBox 360 development. If the XBox SM3 is a strict superset of PC SM3 what is the reason to block it from the developer?

The fact that there isn’t anything between SM3 and 4 on the PC doesn’t count as they already use a special profile for the XBox. This means that the XNA framework already have added something that doesn’t exist on Direct3D. We had see this before with SM2 and SM2.X but in this case every card that supports a 2,X profile although supports plain SM2.

In the context of the XNA framework aims it simply doesn’t make sense to block a shader model from usage if it is supported.

The missing thing could something really small. Maybe no one will every write an HLSL shader that can compile as PC SM3 but not as XBOX SM3 shader.

It’s possible that the missing feature is not inside the hardware and only the system software is not able to understand and optimized PC SM3 shaders. But even then it’s still a missing feature.

 

[Fran]

If there is no feature missing why it isn’t supported? The XNA framework should be the great unification of PC and XBox 360 development. If the XBox SM3 is a strict superset of PC SM3 what is the reason to block it from the developer?

The XBox 360 shader model is not exactly the same as SM3.0, cause it's "optimised" for game developing on one single platform: several things are different because they don't have to be compatible with any other hardware. The HLSL implementation reflects this difference in terms of the fact that you can't expect to drop every possible SM3.0 hlsl shader and see it compile and execute exactly the same on the 360. This is more a syntactic problem, I'd say.

In terms of features, the Xbox 360 shader model is a super set of SM3.0, there's nothing you can do with SM3.0 that you can't do with the 360 and there are several things that you can do on the 360 and not with SM3.0.

I think they have sacrificed a bit of compatibility with the PC world for greater performance and flexibility. We are working at very low level here.

Fran/Fable2

 

[Fafalada]

This means that the XNA framework already have added something that doesn’t exist on Direct3D

D3D already misses a ton of things that are in existing PC hardware - there's just no useful reason for a console to follow its specification too closely.

 

[expletive]

No DX10 for you!

http://www.1up.com/do/newsStory?cId=3153097

...according to ATI themselves. "Xbox360 cannot run DX10, and confirmed what I said earlier about the extended functionality. The Xbox360 has unique features including memory export that can enable DX10-class functionality such as stream-out," said an ATI spokesperson. "From what we're hearing, Crysis will support DX9 with some sort of use for DX10 features. It's likely that those DX10 visuals can be replicated on the Xbox360, but it can't be properly called DX10.

Does seem like memexport is more relevant than I thought in terms of creating DX10-like graphics.

 

[blakjedi]

DX10 is a featureset for PC hardware... as long as the similar quality effects can be done on the console... why does it matter? Myabe consoles could be certifed as "DXX level" as opposed to "DXX compliant"...

 

[Rolf N]

Maybe you could just emancipate yourself and stop letting Microsoft dominate your thought processes.

 

[ERP]

In terms of features, the Xbox 360 shader model is a super set of SM3.0, there's nothing you can do with SM3.0 that you can't do with the 360 and there are several things that you can do on the 360 and not with SM3.0.

There are some DX9 features that have radically different interfaces on 360 because of the differences in the front end of the chip. Instancing has to be implemented differently by the application.

For the most part though MS jump through hoops to make it look like the PC interface when it isn't a significant bottleneck. If you use D3D Vertex Formats, Vertex shaders are patched the first time a new vertex format is used for example. If you don't use D3DVertexFormats and actually add the extra instructions to the shader, then there is no patching.

 

[zed]

according to ATI themselves. "Xbox360 cannot run DX10, and confirmed what I said earlier about the extended functionality. The Xbox360 has unique features including memory export that can enable DX10-class functionality such as stream-out," said an ATI spokesperson. "From what we're hearing, Crysis will support DX9 with some sort of use for DX10 features. It's likely that those DX10 visuals can be replicated on the Xbox360, but it can't be properly called DX10."

http://www.1up.com/do/newsStory?cId=3153097

personally its all moot, as what is d3d10?
drawing a simple shaded triangle with the d3d10 interface, is it d3d10?

 

[MasterDisaster]

http://www.1up.com/do/newsStory?cId=3153097

personally its all moot, as what is d3d10?
drawing a simple shaded triangle with the d3d10 interface, is it d3d10?

they are talking of "dx 10 visuals", non of "d3d10", they are talking about the visual obtainable with dx10 (effects, advanced geometry functions, etc)

 

[liolio]

does anybody think that the xenos is almost as dx10 as the first gen directX10 pc cards will be.
I remenber reading in the article about directX10 from MS conference that some fonctionnality of DX0 won't be usefully implement in hardware in the first gen cards (lake of power).

So I guess it's all bullshit Xenos is just more than a directX9 card.
i'm happy with that description.

 

[MasterDisaster]

does anybody think that the xenos is almost as dx10 as the first gen directX10 pc cards will be.
I remenber reading in the article about directX10 from MS conference that some fonctionnality of DX0 won't be usefully implement in hardware in the first gen cards (lake of power).

So I guess it's all bullshit Xenos is just more than a directX9 card.
i'm happy with that description.

what do you mean?
it's a bullshit that xenos is more than a dx9 gpu????
that R600 is not dx 10 compliant???

try to explain