JAppleyard wrote:
> People are doing raytracing on CUDA already

With fixed recursion levels.  Not good enough.

...Chambers

Post a reply to this message

Chambers wrote:
> JAppleyard wrote:
>> People are doing raytracing on CUDA already
> 
> With fixed recursion levels.  Not good enough.

Although I don't really think it's worth the POV-team's limited time 
working on it, raytracing with limited recursion levels (and maybe other 
restrictions) on the GPU could be very useful for fast lower-quality 
renders used while modeling a scene -- similar to the current Quality=n 
setting.

Post a reply to this message

Kevin Wampler <wam### [at] uwashingtonedu> wrote:
> Although I don't really think it's worth the POV-team's limited time 
> working on it, raytracing with limited recursion levels (and maybe other 
> restrictions) on the GPU could be very useful for fast lower-quality 
> renders used while modeling a scene -- similar to the current Quality=n 
> setting.

  It's not only about the quality of the rendering (in other words,
whether you could express all the textures, media and lighting features
of POV-Ray in CUDA), but also whether you can trace all POV-Ray primitives
with CUDA. Can you, for example, trace isosurfaces, the poly object or the
julia object with CUDA (even the next generation one)?

-- 
                                                          - Warp

Post a reply to this message

Warp wrote:
>   It's not only about the quality of the rendering (in other words,
> whether you could express all the textures, media and lighting features
> of POV-Ray in CUDA), but also whether you can trace all POV-Ray primitives
> with CUDA. Can you, for example, trace isosurfaces, the poly object or the
> julia object with CUDA (even the next generation one)?

I definitely agree with this, but I think even an incomplete set of POV 
features could be implemented on a GPU it might still prove very useful 
for modeling.  I suppose the question is if enough of the features can 
be implemented to be generally useful.  Unfortunately I haven't ever 
messed around with GPU programming so I can't answer this question.

Again, I'd personally prefer that the POV team spend their time on other 
things, but I still sort of hope that someone else who's interested 
makes a solid attempt at this sometime.

Post a reply to this message

Kevin Wampler wrote:
> Chambers wrote:
>> JAppleyard wrote:
>>> People are doing raytracing on CUDA already
>>
>> With fixed recursion levels.  Not good enough.
> 
> Although I don't really think it's worth the POV-team's limited time 
> working on it, raytracing with limited recursion levels (and maybe other 
> restrictions) on the GPU could be very useful for fast lower-quality 
> renders used while modeling a scene -- similar to the current Quality=n 
> setting.

The problem really is that the entire engine would need to be rewritten 
from scratch to work this way.  Considering that it is not yet clear if 
GPGPUs (General Purpose Graphics Processing Units... isn't that an 
oxymoron?) will perform better in such branching conditions than more 
traditional multicore processors (Intel doesn't think so, which is why 
they're working on Larrabee), the amount of work necessary just isn't 
worth it for a partial implementation.

...Chambers

Post a reply to this message