[Mesa-dev] [Mesa-users] Fwd: Issues with removal of classic OSMesa

[Andreas Fänger]

Hi Brian,

thanks.

>> BTW, when you say "antialiasing" below, what exactly do you mean?

We are using GL_POLYGON_SMOOTH_HINT
This works well for our use-case. However, if MSAA produces better results,
then this would be good, too.

In general, quality is really important for us. That's why we need both
features, similar to the classic swrast renderer (but with a better
performance)

Andreas

-----Ursprüngliche Nachricht-----
Von: mesa-users <mesa-users-bounces at lists.freedesktop.org> Im Auftrag von
Brian Paul
Gesendet: Montag, 4. Januar 2021 20:47
An: mesa-dev at lists.freedesktop.org; mesa-users at lists.freedesktop.org
Betreff: [Mesa-users] Fwd: Issues with removal of classic OSMesa

Hi Andreas,

I'm forwarding your message to the mesa-dev list for better visibility.

BTW, when you say "antialiasing" below, what exactly do you mean?

-Brian


-------- Forwarded Message --------
Subject: 	[Mesa-users] Issues with removal of classic OSMesa
Date: 	Thu, 31 Dec 2020 12:56:04 +0100
From: 	Andreas Fänger <a.faenger at e-sign.com>
To: 	mesa-users at lists.freedesktop.org

Hi,

I've just seen that classic OSMesa has been removed (again) from Mesa3D a
few weeks ago with this commit "mesa: Retire classic OSMesa".

We are still actively using classical OSMesa for high quality rendering of
still images in a headless environment with no GPU support (server-based
rendering on windows and linux)

Unfortunately, none of the alternative software renderers provide all the
features that we require, which is antialiasing and anisotropic filtering.
The current state is (correct me if I'm wrong)

* softpipe: anisotropic filtering is supported, no antialiasing

* llvmpipe: no anisotropic filtering, has MSAA

* openswr: no anisotropic filtering, has MSAA, no OSMesa interface (?)

We had hoped that classical OSMesa is only removed when there is a full
replacement after the discussions in 2016 when OSMesa was about to be
removed for the first time

https://lists.freedesktop.org/archives/mesa-dev/2016-March/109665.html

https://lists.freedesktop.org/archives/mesa-users/2016-March/001132.html

and the commit that reverted the removal

http://cgit.freedesktop.org/mesa/mesa/commit/?id=9601815b4be886f4d92bf74916d
e98f3bdb7275c

Are there any plans to enhance the renderers so that at least one of them is
providing both anisotropic filtering and antialiasing?

As far as I know, anisotropic texture filtering is also one of the OpenGL
4.6 requirements.

In 2016 I was told that there are only very few developers involved in
llvmpipe and that chances are not high that someone is going to port the
softpipe anisotropic filtering implementation as llvmpipe is much more
complex. Is there any change in that situation?

If there are no such plans, is there any chance of reverting this commit
again so that classical OSMesa is available for windows and linux in mesa
>20?

Regards,

Andreas Fänger