mone schrieb:

> I have not much experience with radiosity. If I recollect it correctly the
> calculated values are somehow attached to the object and can be stored in a
> file? So it possibly doesn't matter much when the image size is increased with
> radiosity? Maybe the experts can say more about this :).

In a perfect world, all radiosity samples you ever need would be 
gathered during radiosity pretrace, which is basically independent of 
screen resolution.

In practice, most people don't set the radiosity parameters high enough 
to have pretrace do a good enough job; in that case, a high-res image 
may add more samples during final trace than a low-res image.

OTOH, even the number of additional samples during final trace just 
grows linearly with the number of pixels.

Another effect that needs to be considered is radiosity sample lookup 
during the final render; in an ideal world the time spent on this would 
increase roughly linearly with number of pixels; however, due to a 
high-res image usually generating more radiosity samples in total, the 
per-pixel time spent on looking up radiosity samples will increase, so 
the total time spent on sample lookup will increase nonlinearly.

All in all, however, I guess time required for radiosity will increase 
sub-linearly with number of pixels in practice, due to pretrace time 
remaining basically unchanged (unless you change radiosity parameters).

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