WGL_ARB_render_texture on Linux/nvidia

Dave Moore

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Aug 15, 2003, 10:54:58 AM8/15/03

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Hi All,
Does anybody know whether the WGL_ARB_render_texture extension is
typically supported by Linux OGL drivers?. Is it hardware dependant or
is it supported by all new graphics hardware?.

Regards,
Dave

Jason Allen

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Aug 15, 2003, 12:52:09 PM8/15/03

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All WGL extensions are Windows only. There is no equivalent Linux extension
yet.

Jason A.

"Dave Moore" <dave.m...@baesystem.com> wrote in message
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Dave Moore

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Aug 15, 2003, 1:46:45 PM8/15/03

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"Jason Allen" <jra...@yahoo.com> wrote in message
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> All WGL extensions are Windows only. There is no equivalent Linux
extension
> yet.

Why is this?. I mean, surely the capability is provided ultimately by the
hardware's capabilities, not the host processor's OS?. Is there no GLX
equivalent?.

Regards,
Dave

M@

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Aug 15, 2003, 3:00:26 PM8/15/03

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There is (or was) GLX_ARB_render_texture, but I haven't seen any spec on it, and so far only ATI's linux drivers expose the
extension string (don't know if it actually works).

"Dave Moore" <dave_m...@post2me.freeserve.co.uk> wrote in message news:bhj6ba$6je$1...@newsg1.svr.pol.co.uk...

Dave Moore

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Aug 15, 2003, 3:17:39 PM8/15/03

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> > All WGL extensions are Windows only. There is no equivalent Linux
> extension
> > yet.
>
> Why is this?. I mean, surely the capability is provided ultimately by the
> hardware's capabilities, not the host processor's OS?. Is there no GLX
> equivalent?.

Ok. With a bit extra research, it looks like I need GLX_ARB_render_texture.
Does anybody know whether nvidia or ATI support this in any of their Linux
drivers yet?.

Ta,
Dave

Jason Allen

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Aug 15, 2003, 4:30:23 PM8/15/03

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There actually is no such extension. At least not something that was every
approved by the ARB. Look in the SGI extension registry
(http://oss.sgi.com/projects/ogl-sample/registry/) for a list of ARB
approved extensions.

Jason A.

"Dave Moore" <dave_m...@post2me.freeserve.co.uk> wrote in message

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Jon Leech

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Aug 15, 2003, 7:13:44 PM8/15/03

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In article <bhj6ba$6je$1...@newsg1.svr.pol.co.uk>,

Dave Moore <dave_m...@post2me.freeserve.co.uk> wrote:
>
>"Jason Allen" <jra...@yahoo.com> wrote in message
>news:Zc8%a.3541$YC.1...@twister.austin.rr.com...
>> All WGL extensions are Windows only. There is no equivalent Linux
>extension yet.
>
>Why is this?.

Basically because the IHVs haven't felt there's enough demand for it
to spend time on this at the ARB, when the upcoming superbuffers
extension will accomodate render-to-texture among many other
capabilities.
Jon Leech
SGI

juij

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Aug 17, 2003, 3:39:09 AM8/17/03

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NVidia 43.63 driver reports GLX_SGIX_pbuffer on Linux for server and
client glx extensions. Maybe it's it what you looking for?

--
Wojtek

Dave Moore

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Aug 17, 2003, 2:04:58 PM8/17/03

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"juij" <hate...@noexist.pl> wrote in message
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I don't think so. I believe 'pbuffer' and 'render texture' are two separate
extensions or 'capabilities'.

Dave

Ruud van Gaal

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Aug 18, 2003, 9:22:44 AM8/18/03

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Not really; a pbuffer is a memory region that is offscreen but still
hardware accelerated. On SGI O2's at least, you use PBuffers to do
texture draws.
A glCopyTexSubImage2D() then only copies by reference, not the pixels
themselves.

PBuffers and Texture buffers (whatever they're called) would be very,
very similar.

Ruud van Gaal
Free car sim: http://www.racer.nl/
Pencil art : http://www.marketgraph.nl/gallery/

Rob

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Aug 18, 2003, 11:02:29 AM8/18/03

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and hence sitting a texture onto a deforming mesh is easy, and then
setting the video capture to be the SAME PBuffer as the texture
makes video fx simple!

but then, I like O2's ...

> PBuffers and Texture buffers (whatever they're called) would be very,
> very similar.
>
> Ruud van Gaal
> Free car sim: http://www.racer.nl/
> Pencil art : http://www.marketgraph.nl/gallery/

--
Rob Fletcher, University of York, UK
[Spamtrap - Remove the "y" to reply]

Georg Klein

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Aug 20, 2003, 7:01:37 AM8/20/03

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On Mon, 18 Aug 2003 13:22:44 +0000, Ruud van Gaal wrote:
[snip]

>>I don't think so. I believe 'pbuffer' and 'render texture' are two separate
>>extensions or 'capabilities'.
>
> Not really; a pbuffer is a memory region that is offscreen but still
> hardware accelerated. On SGI O2's at least, you use PBuffers to do
> texture draws.
> A glCopyTexSubImage2D() then only copies by reference, not the pixels
> themselves.
>
> PBuffers and Texture buffers (whatever they're called) would be very,
> very similar.

Are you sure about this?
E.g. what happens if the pbuffer is modified after the glCopyTexSubImage2D
call? Does it remember to do an actual copy then?

--
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Ruud van Gaal

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Aug 21, 2003, 11:58:48 AM8/21/03

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On Wed, 20 Aug 2003 12:01:37 +0100, "Georg Klein" <gs...@cam.uc.ak>
wrote:

Yes. In fact, the O2's copy-by-reference is a complete hack which has
a lot of prerequisites (but useful for live video mapping on a moving
3D object).

A pbuffer is a simple memory buffer on the card, so is the texture.
Perhaps the superbuffers extension that is coming is something to
unify both...