[Bf-funboard] GPU accelerated rendering

[Robert Wenzlaff]

On Tuesday 19 October 2004 06:49, Bart wrote:
> Here is another interesting thing about GPU rendering:
>
> Nvidia Gelato
> http://film.nvidia.com/page/gelato.html
>
> Bart wrote:
> > Hey this would be amazing!!!
> >
> > car wrote:
> >> Oh wow that is some nice stuff for the render times  ... One can only
> >> hope that others here will try and do that with the GPU...

The problems I see with GPU assisted rendering, is the fact that no standard 
has shaken out of the industry yet.    If you are a pro-house using custom 
tools, you can specify "All computers for this movie will have BrandX ModelY 
graphics cards" (Note who nVidia is targeting with the Gelato link...  
"Gelato offers all the features that film and television customers demand 
today, and is both flexible and extensible allowing for easy integration into 
your existing production pipeline"...) .   

For GPU assisted disply/editing we have such a standard, OpenGL (and even that 
causes us fits sometimes).    For a general purpose app that must strive to 
support all decent GPU's, there are basically two paths to go by:

1) Wait for a standard to settle out.  It could be a while, each GPU 
manufacturer wants to lock customers into their cards.  There's little 
advantage to standardizing (for them) as long as they have a chance to reach 
the top. (Note how Gelato ships with an API, not an input/output format.  
I'll bet that when/if ATI ships a similar product, their API will be 
incompatible with nVidia's.  Whose API do we hardcode in?)

2) Make a standard interface to Blender's rendering engine that can take 
"plug-in libraries" that convert what they can to a specific GPU API and 
returns the render data in the form Blender expects.   This means that anyone 
wanting GPU assisted rendering for CardX would need to write, or find someone 
to write the infterface for their card.  If a standard does shake out, then 
that plug-in lib will be the "official" one.  A lot of this work is already 
being done to support external renderers.  

I'll bet a renderman compliant interface to the GPU will be something that 
most manufacturers will ship, or will become available through 3rd party 
efforts (Gelato has one, and it's even free and Open Source!), so it may take 
care of itself once the Blenderman project is up and running.  Instead of 
dividing the developer community on GPU specific tasks, let's leverage GPU 
assisted rendering to the advantage of an existing, general use, project.   
On-the-fly RIB import/export gives us Gelato _and so much more_.... 

The point is, yes, it's a cool idea.  Running blindly to chase every cool idea 
via the quickest/dirtiest method is not a cool idea.  There's a lot of cool 
ideas out there that have ended up as dead-ends. (Hey, let's start a 
Blender.org project that will let us save our output to Betamax!) 

************************************************************
Robert Wenzlaff                  rwenzlaff at soylent-green.com