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Qu0ll
04-21-2009, 09:48 AM
I am looking at OpenGL as a possible key technology for a major new project and I would like some more information on support in the Windows environment.

1. It looks to me as though the Windows OpenGL DLLs are all dated from several years ago. Are there more recent OpenGL libraries for Windows which are different from the "standard" ones that come with Windows?

2. Will OpenGL run on Windows 7?

3. Is development of OpenGL support on Windows done by non-Microsoft organisations and people? I am hoping we are not relying on Microsoft to implement it with each version of Windows.

Thanks,

-Qu0ll

ZbuffeR
04-21-2009, 12:09 PM
1. the opengl32.dll provided by windows is just a stub to call an actual GL implementation. To get recent features you just need a recent graphic driver, then at runtime ask for these features.

2. yes. According to some beta testers it already does. Not surprising, as vista and W7 drivers are almost the same.

3. see 1. If you have an nvidia card, you will get the nvidia implementation of OpenGL. Keep in mind that the GL *specifications* are done by a group of organizations.

To better understand how the extensions can be added without needing a new opengl32.dll, read this page :
http://www.opengl.org/wiki/Getting_started#OpenGL_2.0.2B_and_extensions

Qu0ll
04-21-2009, 01:27 PM
Thanks for the reply.

Given that you seem to imply that the OpenGL implementation is done through the graphics card, does that mean that only certain cards will support OpenGL and that it simply won't run on machines without the "right" cards?

ZbuffeR
04-22-2009, 01:55 AM
I did not mention this, but without the "right cards/drivers" you have still the MS-provided software implementation, OpenGL 1.1 for all windows versions before Vista, GL1.4 with vista/W7.

The idea is if you don't have the hardware, it is almost useless to provide modern features, it would be 1000 times slower, basically unusable, so only basic stuff is available.

Mesa3D still provide GL 2.1 and a lot of modern features through a software implementation, if really you have to.

tranders
04-25-2009, 05:22 PM
I did not mention this, but without the "right cards/drivers" you have still the MS-provided software implementation, OpenGL 1.1 for all windows versions before Vista, GL1.4 with vista/W7.

FWIW, Vista/W7 still only provide software OpenGL 1.1 without a working ICD (Installable Client Driver) -- you will not get OpenGL 1.4 without some HW support.

Pipeline article (http://www.opengl.org/pipeline/article/vol003_7/)