"clipka" <nomail@nomail> wrote:
> "nemesis" <nam### [at] gmailcom> wrote:
> If you have a scene containing a complete 10-storey house, and you only want to
> render a single room - it'll kill.
>
> It's an extreme example, but it shows that (a) your question cannot be answered
> without knowing the scene, and how much of it is actually visible, and (b)
> processing power has not increased so much to just go for plain brute force.

I'd never put a full building to render when only targetting a room.  It's up to
the user to render their scenes in little passes and then combine them -- or
not, in this case.  Perhaps some sort of "radiosity bounding box" could help
here?

> In fact, instead of spending the processing power to speed up *potential* later
> renders of other parts of the scene, I'd rather see the added power invested in
> (a) more detail, (b) higher quality and (c) faster results.

It seems to me faster results are dependent on parallelization of the
"radiosity" calculation step and such step is being hampered of achieving such
parallelism exactly by not being able to know in advance how much each thread
should allow to "be visible".  At least in the case of different instances of
povray rendering chunks of a larger image... as was the old approach to
parallelism.  Not sure threads would improve the situation here, possibly yes,
by having shared datastructures.  OTOH, I'm aware of the locking issues...

> - First image is pretraced, producing all necessary samples for the first shot
> - First image is rendered, no additional samples are needed
> - Second image is pretraced, re-using what the first pretrace produced, and
> adding what is missing
> - Second image is rendered, no additional samples are needed
> - ...

In the current implementation, second and later calculations are not stored,
they just load the original calculations and calculate whatever is needed anew
without ever adding up and storing to the original radiosity file.  Even if
your 3rd frame of animation would benefit from them...

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