About Longhorn's graphics driver model...

[Jawed]

And a big clue about IHV attitudes might well be NVidia's resistance towards building unified shader hardware.

Jawed

 

[AlNom]

Design goal: 1/10th overhead of D3D9

Does that extend to D3D8? (majority of current games)
edit:I mean, there is going to be backwards compatibility with that, right?

Would it affect opengl in any way? (Actually, will MS include better support for opengl in longhorn? unknown?)

 

[trinibwoy]

Well since everything pre-DX9 is going to be mapped to the DX9 API I would assume that they benefit from the improvements as well. One of the slides also claims improvements in OpenGL.

 

[Frank]

Design goal: 1/10th overhead of D3D9

Does that extend to D3D8? (majority of current games)

Would it affect opengl in any way? (Actually, will MS include better support for opengl in longhorn? unknown?)

I don't think Microsoft will supply any support for OpenGL. There's just nothing to gain for them for doing so.

 

[trinibwoy]

Not according to the fifth slide from the first link -

Continue OpenGL support
Important component of the Windows platform, particularly for high-end workstation applications

and

Microsoft OpenGL improved
Hardware accelerated
Via Common Graphics Pipeline
Upgraded API support for CAD applications
GL 1.2, Necessary Extensions

 

[Frank]

Not according to the fifth slide from the first link -

Continue OpenGL support
Important component of the Windows platform, particularly for high-end workstation applications

and

Microsoft OpenGL improved
Hardware accelerated
Via Common Graphics Pipeline
Upgraded API support for CAD applications
GL 1.2, Necessary Extensions

I hope they do that. That would be very nice!

 

[AlNom]

GL1.2? As in... not OpenGL 2.0 or is that a different number?

 

[Demirug]

Design goal: 1/10th overhead of D3D9

Does that extend to D3D8? (majority of current games)
edit:I mean, there is going to be backwards compatibility with that, right?

Would it affect opengl in any way? (Actually, will MS include better support for opengl in longhorn? unknown?)

Yes, even older DX versions will get some benefit from the new model. But it is possible that we see some compatibility problems with current games. The reason for this is that microsoft have to write a new runtime for each DirectX version because LDDM driver did not support older DDIs like current XP drivers. If a game use a "feature" of a current runtime that is not documented and not reimplemented in a longhorn runtime the game will not run or maybe crash. I already know some games that use such "features" but there is hope that this "features" are in the new runtimes, too.

OpenGL support is a part of the LDDM. The kernel part of LDDM can be used for the D3D/WGF and OpenGL user mode drivers. This will make it easier to write drivers. But even if the IHV will not include an OpenGL driver you can use OpenGL with your GPU. Longhorn contains an OpenGL driver that convert OpenGL calls to D3D calls. This will not as fast as a native OpenGL driver from a IHV but faster than the current software OpenGL driver in Windows XP.

 

[Wunderchu]

We can also expect Microsoft to come through with a much more detailed and stringent specification for WGF 2.0. It seems that the extent to which DX9 hardware can vary has gotten their attention. In one of the sessions we attended, it was stressed that Microsoft doesn't want software developers to have to cater to multiple hardware paths in order to get good performance. In fact, they went so far as to say that they wanted a tight enough spec so that WGF 2.0 hardware would all support the same features implemented in the same way. Fore shadowing this, all capability bits have been eliminated from WGF 2.0 (meaning that either hardware either will or will not support exactly the same set of functions as all other WGF 2.0 hardware). Vendor specific extensions will still be accessible through OpenGL, and we can still expect the top graphics IHVs to try and differentiate themselves somehow. It may just become more of an AMD/Intel type of race where the differences come down to the underlying hardware architecture and technology.

From: http://www.anandtech.com/tradeshows/showdoc.aspx?i=2403&p=4

 

[trinibwoy]

In fact, they went so far as to say that they wanted a tight enough spec so that WGF 2.0 hardware would all support the same features implemented in the same way.

From: http://www.anandtech.com/tradeshows/showdoc.aspx?i=2403&p=4

NV40 and R420 support all the same features of SM2.0 (besides the precision difference) yet their architecture is quite different. Is Microsoft going to tell ATI to implement Nvidia's Z/Color ROP scheme and tell Nvidia to start assigning tiles to each quad like ATI does? Or does this apply to higher-level capabilities?

 

[3dcgi]

NV40 and R420 support all the same features of SM2.0 (besides the precision difference) yet their architecture is quite different. Is Microsoft going to tell ATI to implement Nvidia's Z/Color ROP scheme and tell Nvidia to start assigning tiles to each quad like ATI does? Or does this apply to higher-level capabilities?

Higher level capabilities. Microsoft can dictate what ROPs are supported, but not how that support is implemented.