"Samour" <nomail@nomail> wrote:
> Now for Rayleigh the phase function is close to what is found in the literature
> multiplied by some normalizing constant (the equation in the literature is
> 0.75*(1.0 + Sqr(alpha)), POV-Ray uses 0.799372013 instead of 0.75), and for
> Henyey-Greenstein it is identical.

I just checked the math, and the factors seem to be wrong indeed; I came up with
the following factors:

- Rayleigh scattering:     3/4
- "Mie Hazy" scattering:   1/2
- "Mie Murky" scattering: 33/83

(For the "Mie" formulae, my attempt at symbolic integration had me come up with
1 and 66/83, respectively, but numeric integration gave me values matching the
above quotients, so I guess I just goofed by a factor of 2.)

Henyey and isotropic scattering seem to be properly normalized.


(Normalization appears to be for a spherical integral of 4 pi, not 1, or else
I'm mistaken.)

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