Le Forgeron wrote:

>
>> Slime wrote:
>>>> Hello. Is any way to put my radeon 9800 pro to render the scene in
>>>> povray? Some script or else?
>>>
>>> No, POV-Ray implements the ray-tracing algorithm which is not used
>>> by video cards.
>>>
>>> http://tag.povray.org/povQandT/miscQandT.html#3dcard
>>
>>
>> 3D cards do actually have some things which are useful to
>> ray-tracing, like all the geometry transformation operations, and
>> the ability to run the same code many times on different data very
>> efficiently.  In fact I believe some people have already written ray
>> tracers for 3D cards with pixel shader support.
>>
>> Maybe in the future there will be a way for POV to take advantage of
>> some of these operations.
>
> Unless PoV turn into a stupid triangle-renderer, as well as becoming
> non- portable and very hardware aware, do not count on it (and it
> would at best be a very marginal gain (not even warranted)).

http://moe.jrq.ch/?iC=pjs&iP=psrt

Is a good example.

> Now, if you could increase your understanding of
> http://tag.povray.org/povQandT/miscQandT.html#3dcard , I think I
> would be happier :-)

I think I would be happier if you could increase your understanding of how
pixel shaders work on the latest 3D cards :-)

I haven't looked at the code in detail, but the basic idea is that you give
the "data" to the pixel shader pipeline in the form of textures.  The pixel
shader in the GPU can then perform the usual ray-object intersection code,
and give the output in the form of a texture.  The main CPU then reads this
texture and uses it to construct the final image.

The pixel shader GPU has been designed in hardware to run the same code on
lots of data very quickly, this is ideal for raytracing calculations.  And
it isn't impossible to use it for raytracing calculations.  In the future as
GPUs allow longer pixel shader programs to run, doing more and more complex
ray tracing will become possible.

Google for "pixel shader raytracer", I'm sure you'll come up with something.
IIRC it was either NVidia or ATI that have a raytracer as one of the demos
in their pixel shader development kit.

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