Re: [matplotlib-devel] opengl backend

[Michael D. <md...@st...>]

On RHEL4, I get the following message:

   This OpenGL does not support framebuffer objects

I understand that I'm probably just suffering from a relatively old 
Mesa/OpenGL stack here.  And obviously, just because some older systems 
won't support this is not a reason to not include it as an optional backend.

Can you possibly send a screen shot to the list for those of us who 
can't see it?  Is the quadmesh interpolated?  That would be a huge 
improvement over anything we can do currently.

As for developing a full OpenGL backend, note that the process of 
writing a backend has been greatly simplified as of 0.98.x (there's only 
about four rendering methods to implement now, with three more optional 
ones to re-implement for performance reasons).   You can start by 
looking at backend_bases.py.  I'm happy to help with any questions you 
have as you go along, but as I don't have a working pyglet/OpenGL, I 
can't be of much help for testing.

Cheers,
Mike


Ryan May wrote:
> Paul Kienzle wrote:
>   
>> Hi,
>>
>> There was a recent discussion about opengl and matplotlib in the
>> context of matplotlib rendering speeds.
>>
>> At the scipy sprints we put together a proof of concept renderer
>> for quad meshes using the opengl frame buffer object, which we
>> then render as a matplotlib image.  Once the data is massaged
>> to the correct form we were seeing rendering speeds of about
>> 10 million quads per second. See below.
>>
>> Using this technique we can get the advantage of opengl without
>> having to write a full backend.  Please let me know if you have
>> time to contribute to writing a more complete backend.
>>     
>
> I know that I (as the other contributer :) ) plan on making this into a 
> full backend provided:
>
> 1) The quadmesh code can be shown yield the gains when integrated into 
> matplotlib more fully
>
> 2) I find the time (which is a matter of *when*, not if)
>
> I'm certainly finding thus far that pyglet makes it a lot easier to do a 
> full backend than some of the other python->opengl methods I'd explored 
> in the past.
>
> Ryan
>   

-- 
Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA