Using Direct X

[Kaerli]

The current opengl performance problems with Vista are due to the graphics drivers, not Vista itself. So it's not MS's fault, blame the graphics vendors

I have heard that M$ made writing Vista graphics drivers into a royal PITA though...

[Xordan]

Even if true that's no excuse for these multi-billion dollar companies who had months, if not years to write them before release.

[Induane]

Part of the problem is actually, at least according to msdn article I read, that windows vista provides opengl support in a similar but reversed manner to the way wine handles d3d, which is by routing opengl calls to directx equivalents - so opengl in vista is provided via a wrapper, which they claim is necessary because the desktop uses directx so you can't switch renderer's on the fly.

[Xordan]

Well, both the ati and nvidia vista drivers claim 'native opengl support', so you'll probably find that opengl can either be done natively in the driver, or by rerouting opengl calls to directx in software.

[Induane]

You're right!! I did some digging and found out that it IS possible now thank goodness.  Sounds like Microsoft is deliberately trying to kill opengl, but failing

The reason why OpenGL was not ever officially supported by Microsoft was because of Direct3D. Direct3D is Microsoft’s driver model whichis intended to make OpenGL unnecessary. However many games and applications use OpenGL even today. With Windows Vista, Microsoft made it clear that OpenGL support would only work as a layer sitting on top of Direct3D. There was going to be translation involved and thus, a performance hit.

This week the Khronos group, which is responsible for developing and maintaining OpenGL, has released a report indicating that OpenGL support will now be natively supported in Vista without layering over Direct3D. Using standard Windows installable client driver (ICD), OpenGL will be fully accelerated and be fully compatible with Windows Vista's Aeroglass UI. In fact, Khronos says that by the time Windows Vista ships, Aeroglass performance on OpenGL will be superior to that of Direct3D. According to Khronos and NVIDIA:

    * Hardware overlays are not supported
    * Hardware OpenGL overlays are an obsolete feature on Vista
    * ATI and NVIDIA strongly recommend using compositing desktop/FBOs for same functionality

However, the OpenGL ICD drivers must still bedownloaded and will not ship on the Windows Vista installation disc. Khronos said that NVIDIA already has a beta 2 ICD OpenGL driver available and ATI will release its own soon. If no ICD is present, Windows Vista will rely on thelayered OpenGL mode by default and only offer basic functionality.

[lordraleigh]

You're right!! I did some digging and found out that it IS possible now thank goodness.  Sounds like Microsoft is deliberately trying to kill opengl, but failing

Still I wonder if I should keep with Windows XP as long as possible, or until Vista Sevice Pack 6 is released.

And yes, coding support for Direct X is an utter waste of time for a game that uses an open-source engine and that is intended to work on other OSes besides Windows. Why won't PS support DirectX? Because it's intended to be multi-platform and not an Windows-only game, because it would duplicate efforts and for similar reasons it won't have Havok 2.0 physics engine as a feature as well, I believe that open-source projects should avoid alltogether relying on commercial copyrighted technologies for their creation.