Stephen nous apporta ses lumieres en ce 23-03-2007 04:37:
> "Cousin Ricky" <ric### [at] yahoocom> wrote:
>> "Stephen" <mcavoys_AT_aolDOT.com> wrote:
>>> Because there is no atmosphere in space the shadows should be deep and
>>> sharp (The ambient for your textures should be 0 or very close).
>> Atmospheric scattering isn't the only factor.  The Earth casts formidable
>> backlighting.  In low Earth orbit, the Earth occupies nearly all of one
>> side of the universe.  At the Earth-Moon distance, the Earth reflects
>> almost 60 times more light than the Moon.

>> The sharpness of the shadows depends on the size of the light source.  The
>> Sun spans about 1/2 degree in diameter, enough for subtly, but noticeably
>> fuzzy shadow edges.  An extreme case is the penumbral area of a lunar
>> eclipse.

> I stand (or sit) corrected. That would call for a very large area light.

> Stephen


You can have an earth place holder (about the right apparent surface and 
coloration) and use radiosity. Or, you can use a large area_light to simulate an 
earth, or some other close-by off field planet. In that case, using look_like 
with a sphere mapped with an adequate image_map can be nice.
For the sun, use a parallel light not to far and make it an area_light of 
approximatively the right apparent extention.

-- 
Alain
-------------------------------------------------
Unitarian: Shit that happens to one person is just as bad as shit that happens 
to another.

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