Vista supports OpenGL hardware acceleration. The main problem is ATi and Nvidia have yet to release decent drivers.
Microsofts word's on the subject
OpenGL
Windows Vista provides the same support as Windows XP for OpenGL, which allows video card manufactures to provide an installable client driver (ICD) for OpenGL that provides hardware-accelerated support; note that newer versions of such ICDs are required to fully support Windows Vista. If no ICD is installed, the system will fall back to the OpenGL v1.1 software layer in most cases.
What you have to do to make said ICD work:
The OpenGL installable client driver (ICD) can obtain the same level of support for calling kernel-mode services as
the Direct3D user-mode display driver. However, rather than gaining access to kernel-mode services through callback functions like the Microsoft Direct3D runtime supplies through the
pAdapterCallbacks member of the
D3DDDIARG_OPENADAPTER structure and the
pCallbacks member of the
D3DDDIARG_CREATEDEVICE structure, the OpenGL ICD must load
Gdi32.dll and initialize use of the
OpenGL-kernel-mode-accessing functions as shown in the following example.
So the mechanisms are very different and there is a bit of a dichotomy in there.
Nothing is perfect that is a certainty. Backwards compatibilty obviously was jettisoned for several reasons, numerous API changes (DirectX 4-9 are mostly downward compatible with the prior versions) however there are billions (ok it's just hundreds) of compatibility bits they needed. DirectX was not well thought out as it's changed considerably from it's earliest inception. It would have been good if they included a Direct X wrapper program to run prior generation DirectX apps within that to translate into Vista. Much like using Virtual PC with hardware aceleration This only works as far as the DirectX API then comes win32 API support, I guess this was a cow they wanted to shoot quickly.
The emulation they provide is still only OpenGL 1.1. No hardware aceleration or translation into DirectX 10 was provided. OpenGL 1.1 compliance is software only.
There were numerous reasons for DirectX becoming part of the OS, again it was political mostly, this was easily fueled by the need for security (I've heard that before somewhere). ICD's do not have the same interface as Direct3D obviously (as noted in the 2nd quote) because they aren't part of the kernel. This makes developement of ICD's difficult at best (no reference).
I'm not convinced however decent OpenGL support will be easy to have and again all OpenGL programs must be made for Vista system (new binaries etc.) So prior generation games won't work.
Can anyone say Wine for Vista?
My guess is that may be the only route to get the support for your old games (DirectX < 10) in Vista. As for OpenGL considering it's migrating to version 3 within the year (wow 2's life was really short by comparison to 1), there is little incentive for card manufacturers to write for a possibly changing API (new version of OGL) and a interface made of sand (IE it could change at any time we are talking about Microsoft here).
As ussual Microsoft makes something overly complicated. (ISO rejected one of the MS XML based proposed standards recently because ISO already had a nice standard that did the same thing instead of 4000 pages of documentation it had 80 pages of documentation.)
Cyb
