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<div class="moz-cite-prefix">Hi Jupiter,<br>
<br>
Thanks for the details. Mesa DRI (direct rendering
infrastructure) allows Mesa to use hardware graphics acceleration,
and I would expect it to be faster. You said you didn't have any
graphics on the computer you are using. Are you sure about that?
You know modern Intel CPUs often have an Intel graphics processsor
on the same chip. According to the mesa xlib web page<br>
<br>
<a class="moz-txt-link-freetext" href="http://www.mesa3d.org/xlibdriver.html">http://www.mesa3d.org/xlibdriver.html</a><br>
<br>
"
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Effectively, the Xlib driver converts all OpenGL rendering into
Xlib calls." I would expect that to be incredibly slow, maybe 100
times slower than rendering with a graphics card. It may be
especially bad with Chimera because Chimera wants to use lots of
OpenGL capabilities.<br>
<br>
If you wish to pursue this further please use Chimera menu entry
Help / Report a Bug... on the computer of interest. Report a bug
with both the Mesa DRI driver and another with the Mesa Xlib
driver. This will give us all the info about your system and what
OpenGL Chimera is trying to use.<br>
<br>
Tom<br>
<br>
</div>
<blockquote
cite="mid:CAA=hcWRoSp2HKhO0Gaf=Rb3Y3zUPm8tNd5wqRK8VnNEqgbBDKQ@mail.gmail.com"
type="cite">
<pre wrap="">Hi Tom,
Thanks for your response. Let me clarify it in my following embedded comments.
On 3/12/13, Tom Goddard <a class="moz-txt-link-rfc2396E" href="mailto:goddard@sonic.net"><goddard@sonic.net></a> wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Hi Jupiter,
Chimera tries to use modern OpenGL features: shaders, vertex buffers,
instancing, .... It disables some of those features known to be buggy
in mesa. If you start chimera --debug-opengl you can disable more
OpenGL features with a start-up dialog.
</pre>
</blockquote>
<pre wrap="">
I see the debug dialog, but did not change things if I disable some
opengl features.
</pre>
<blockquote type="cite">
<pre wrap=""> You said in your first email that Chimera ran with "very poor
performance when using mesa". It would be helpful to give an explicit
example (e.g. opening PDB yyyy the model rotates at about z frames per
second).
</pre>
</blockquote>
<pre wrap="">
Chimera can be used in mesa, but only in mesa DRI driver.
If I click Tools->Demo-> COX Inhibitors Demo in Mesa DRI driver, a 3D
structure can rotate relatively good. But if I changed to use Mesa
Xlib driver, the performance is significantly deteriorated, the 3D
structure could no longer rotate, instead of drawing line by line.
This was my main question why it could perform 3D rending in Mesa DRI
driver, but very poor in Mesa xlib driver. Most OpenGL applications
work in both mesa DRI and xlib drivers. Is there any workarounds we
could do to run Chimera in mesa Xlib driver?
</pre>
<blockquote type="cite">
<pre wrap=""> Does your X11 VNC render OpenGL using the client graphics driver? It
might just send the OpenGL to the client (ie. displaying) system in
which case performance would depend on the graphics driver of that
system. Performance can be dismal in such a situation because OpenGL
queries have to make a roundtrip across the network connection.
</pre>
</blockquote>
<pre wrap="">
Let me clarify it, I am doing the testing in a local machine, running
Chimera with either Mesa DRI driver or xlib driver. No VNC connection,
no network issues. The hardware is normal graphic driver using mesa
DRI or Xlib. There was no hardware acceleration, no GPU.
Thank you.
Kind regards,
Jupiter
</pre>
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