On Tue, 25 Jun 2002 02:46:53 -0400, Chris Friedl wrote:

> Further, if anyone can point me to some examples of say, a full moon
> shining in a clear night sky, or the sun shining in a bright blue sky,
> then this might help me get where I want to go. Thanks.

A tip on rendering the Moon as seen from the Earth:

"For example the lunar surface has a [bidirectional reflectivity] that
peaks in the direction of incidence [SIEG81].  During a full moon, when
the sun, earth, and moon are nearly in line, this accounts for why the
moon appears as a disk of roughly uniform intensity.  If the moon had a
Lambertian surface, it would, instead, reflect more light at its center
than at its sides."

Foley, van Dam, Feiner, and Hughes, Computer Graphics: Principles and
Practice, second edition, p. 763

The [SIEG81] reference is to Siegel, R. and J Howell, Thermal Radiation
Heat Transfer, second edition, Hemisphere, Washington, DC, 1981

Ignore this, and the moon will look odd.

-Mark Gordon

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