clipka wrote:
> Saul Luizaga schrieb:
>>> Another possibility is to run the main renderer on the CPU, adding 
>>> rays to queues, and sending any "sufficiently large" queues to the 
>>> GPU for processing. I don't know if bandwidth limitations between the 
>>> two would make this viable...
>>
>> Exactly, that is why I asked: "Are absolutely sure there isn't a case 
>> where a GPU can help? maybe in the middle of a rendering/parsing?".
> 
> Note that although the approach /may/ (!) work, it is a /fundamentally/ 
> different approach from what POV-Ray is doing.
> 
> Changing POV-Ray to use that approach would imply virtually a complete 
> rewrite of the render engine.
> 
>> As you can see, maybe bandwidth it isn't much of an issue since The 
>> transfer between the PCIe video card and the Main memory can me made 
>> at 5 GT/s. Is this still insufficient for POV-Ray peak performance?
> 
> So you're looking at peak data transfer rate limits and from them can 
> infer that transfer between CPU and GPU memory space is not an issue?
> 
> Did you consider latency issues, or the overhead created by the OpenCL 
> framework itself? How about the latency for a "function call"?
> 
> If your work packages are large enough, then these are no issues. But in 
> a raytracer, be prepared for rather small work packages.

You just don't like to be corrected due to your intellectual vanity and 
arrogance, leave those aside for good, they don't do anybody any good.

I made a search on p.o-t on the subject and found nothing. The question 
was: "are you ABSOLUTELY SURE it won't work...?" First you say NO. then 
MAY (!) work. Obvious contradiction. Then you made a number of 
assumptions (againg) about me, all of them WRONG and this is for sure 
rude. Posting on p.p was only the right thing to do, since it was a 
suggestion I didn't started a discussion there, but here.

On my first post in this thread: get some perspective dude, it was for 
everyone, from little tech knowledge to the most advanced, of course 
most advanced readers can obvious the explanation/clarification I made 
about OpenCL.

To the subject: I don't know much about GPUs, POV-Ray internals, 
programming, nor OpenCL, but I do know a little about Computer 
electronic architecture. Some of the questions I made are not meant for 
this NG readers not even the TAG-Team but to the POV-Team, so they can 
made calculations about OpenCL.

I think they may have a structured and classified diagram of ALL POV-Ray 
programming structures, knowing approximately how much each structure 
would take in the CPU, so from the data I provided they could see:

1) What GPU capable structures.
2) The amount of time that the selected GPU capable structures could 
take to do a given process.
3) And this should be first, see if it is worth it, to consider the GPU 
aid, if not possible through OpenCL, make a custom framework. If it is, 
calculate how many GPU capable structures there are to have a second 
evaluation, and see if that number is worth the effort.
4) ETC.

So I'm analyzing to the best of my abilities as everyone here, including 
you, but you're taking this too emotional and going for personal attacks 
on me trying to discredit me. I'm just trying to see all possibilities 
of GPU acceleration and have a discussion and maybe lighten up the 
analysis a little for the POV-Team, but maybe is not me place nor even 
non POV-TAG-Team people, so maybe I should just had this addressed to 
the POV-Team for their consideration only and avoid so much "bothering" 
people here. But as you can see there are somethings to say about it 
still...

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