Spectral rendering of the rainbow
I'm implementing a path-tracer to simulate the earths atmosphere using Rayleigh and Mie scattering.
Is the following correct?
To properly render the rainbow I need to use Mie scatterig theory applied to water drops of some diameter.
The reason we see a rainbow is that the phase function for raindrops has two backwards pointing peaks at approx 42 deg and 50 deg (or something like that) AND that these peaks changes a little for different wavelengths.
So if I got this right I can't use for example the Henyey Greenstein phase function because it does not have these peaks and is not wavelength dependant.
Correct?
So, I will need a more accurate phase function to properly simulate the rainbow and possibly other atmospheric effects such as halos.
I found a program called MiePlot that can be used to calculate alot of stuff on Mie scattering.
Can this be used to create a lookup table for a more accurate phase function for different particle sizes? If so, can someone give me some directions on how to use MiePlot for this? Can I create some kind of batch file to calculate the phase function for alot of different wavelenghts and particle sizes and export this to a file?
Thanks in advance,
Patrik
I don't have much background to give any guidance to your question, however I believe I remember seeing a rainbow demo as part of the nvidia sdk. Parameters addressing key phrases in your question.
This topic is closed to new replies.
Advertisement
Popular Topics
Advertisement