[Bf-committers] Proposal: Blender OpenCL compositor

[François T.]

thx for answering to my blog post via your proposal, to answer some of your
questions there :

*expression py* -> only because it is User/Artist oriented. While python is
great for doing this kind of stuff and pretty popular to most people, I'm
not so sure about openCL language. by the way this is not a way to make new
node, it is just a node which can control some parameter or datas in your
comp.
Look at what is done with Expression in AE :
http://www.videocopilot.net/basic/tutorials/09.Expressions/ I don't think it
does need OCL power to do this kind of thing. Probably more for the Nuke
kind of Expression node because it can be do some pixel processing, but then
it is just a wrapper ?
Maybe on a programmer stand point of view it needs to be openCL or
whatever... maybe not for the front end user. IMO this needs to be
consistent with the rest of the scripting language in Blender. Again
production tool :)


*custom passes* are not mask, they are just render passes (normal, P pass,
vector pass... ), but more on a 3d render side rather than the compositor.

*masks* if you refer to the Addon RotoBezier, then yes it is still to be
done IMO. this should be a native tool with all the features that comes
with. Probably a new node any way. As I said RotoBezier is a great work
around in the mean time, but not a production tool at all.

*openFX* please pretty please :D


F




2011/1/16 Erwin Coumans <erwin.coumans at gmail.com>

> Bullet uses its own MiniCL fallback, it requires no external references,
> the main issue is that it is not a full OpenCL implementation (no barriers
> yet etc). We developed MiniCL primarily for debugging and secondary to run
> the Bullet OpenCL kernels on platforms that lack an OpenCL implementation.
>
> The Intel and AMD OpenCL drivers for CPU perform similar to regular multi
> threaded code (pthreads, openpm etc) but it is more suitable for data
> parallel problems and not for complex code with many branches.
>
> So while you can port a compositor or cloth simulation to OpenCL, most
> general purpose code requires large refactoring and simplification causing
> reduced quality, so don't expect miracles.
>
> Still, it will be fun to see compositing, physics simulation etc in Blender
> being accelerated through OpenCL, optionally.
>
> Thanks,
> Erwin
>
> On Jan 16, 2011, at 5:34 AM, Jeroen Bakker <j.bakker at atmind.nl> wrote:
>
> > On 01/15/2011 03:55 PM, (Ry)akiotakis (An)tonis wrote:
> >> On 15 January 2011 09:19, Matt Ebb<matt at mke3.net>  wrote:
> >>> While I can believe that there will be dedicated online farms set up
> >>> for this sort of thing I was more referring to farms in animation
> >>> studios, most of which are not designed around GPU power - now, and
> >>> nor probably for a while in the future. Even imagining if in the
> >>> future blender uses openCL heavily, if a studio has not designed a
> >>> farm specifically for blender (which is quite rare), CPU performance
> >>> will continue to be very important. I'm curious how openCL translates
> >>> to CPU multiprocessing performance, especially in comparison with
> >>> using something like blender's existing pthread wrapper.
> >>>
> >>> cheers,
> >>>
> >>> Matt
> >>> _______________________________________________
> >>> Bf-committers mailing list
> >>> Bf-committers at blender.org
> >>> http://lists.blender.org/mailman/listinfo/bf-committers
> >>>
> >> I have to disagree on that. Almost every 'serious' user today has an
> >> OpenCL capable GPU and they can benefit from an OpenCL implementation.
> >> Besides OpenCL allows for utilization of both CPU and GPU at the same
> >> time. It's not as if it sets a restriction on CPUs.
> > In my understanding the issue is that internal renderfarms have no
> > 'OpenCL' capable GPU (yet). It is not an issue on the user side. Like
> > during durian, we have workstations with medium gpu's and only cpu based
> > renderfarm. The question is how would a cpu-based renderfarm benefit
> > from opencl?
> >
> > Users on the otherhand have different issues. Our user population also
> > have non OpenCL capable hardware/OS's. therefore we still need a full
> > CPU-based fallback or the bulletsolution by implementing an own opencl
> > driver. The bullet solution is complicated in our situation as it needs
> > a lot of external references (compilers, linkers, loaders etc)
> >
> > Jeroen
> > _______________________________________________
> > Bf-committers mailing list
> > Bf-committers at blender.org
> > http://lists.blender.org/mailman/listinfo/bf-committers
> _______________________________________________
> Bf-committers mailing list
> Bf-committers at blender.org
> http://lists.blender.org/mailman/listinfo/bf-committers
>



-- 
____________________
François Tarlier
www.francois-tarlier.com
www.linkedin.com/in/francoistarlier