Alain <kua### [at] videotronca> wrote:

> Does AO mean ambient oclusion? If that's the case, it's only a tiny
> subset of radiosity. It lack the ability to take into account the colour
> and reflectivity of the ocluding object: it may be black or white and
> cause exactly the same darkening.

I know, the point is to cut corners to reduce render times, whilst still ending
up with a nice looking result. AO is a very handy and quick method of adding in
a lot of extra detail, but not a lot of extra render time. Of course it won't
look as realistic as full-on global illumination, but it will certainly make
things look nicer than no GI at all and open up some extra artistic
possibilities.

> NO, it's absolutely impossible to have any kind of soft shadow from a
> point light. Other renderers may /fake/ soft shadows, like you can
> /fake/ focal blur, in a non-realistic way.
> The mechanism that you mention is faking it. It's probably no faster,
> nor beter, than using an area_light in POV-Ray.

I didn't mean a physically correct point light, you are right that a 'real'
point light won't give soft shadows. I did in fact mean the fake method used by
most other render engines when dealing with point lights in 3D software, to give
you extra artistic control and ease of use and still end up with a nice result.
But thankfully the area light method seems to be a good workaround.

After all, if you just want complete physical correctness you're gonna be
sacrificing a lot of render time and artistic flexibility. A lot of CG is about
faking and optimizing things to keep render times under control, especially when
it comes to animations, and even more so when you don't have a render farm at
your disposal.

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