[Radiance-general] Simulating light ray movement inside swimming pool water. Light sources not in the water

[Lars O. Grobe]

Hi and welcome,

you have choosen a difficult topic, as there are many unknown variables 
in what you want to simulate.

But first of all, what glare are you refering to? Glare caused by 
reflections, which could be experienced by someone next to the pool?

Water could be modeled purely as a dielectric. Mist would show the 
effects of bubbles, small particles, anything that makes the clear water 
become somehow misty ;-) So you would have to know whether the water in 
your pool is perfectly clear (e.g. a diver in it would not see a light 
beam when you point a strong spot to it), or whether you would expect 
any kind of particles in there (which would make that light beam become 
visible due to scattering). You may also use mist if there is mist in 
the air over your water surface due to condensation in the (compared to 
the water) colder air.

Second, what is the surface of the water body looking like? On earth, 
due to gravity, you would expect it to be almost perfectly plane, but 
experience tells us that there are small waves and such due to air 
movement, swimmers and such. Unfortunately, the surface geometry of a 
dielectric material has a huge influence on how you perceive it. So you 
would need to know the shape of the water surface in order to simulate 
it. If you go into this, the photon mapping extension may be valuable, 
as it can show caustics as you would see them under a wavy water surface 
on the ground of the pool.

Cheers, Lars.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: lars_grobe.vcf
Type: text/x-vcard
Size: 299 bytes
Desc: not available
Url : http://radiance-online.org/pipermail/radiance-general/attachments/20090722/8134bb3f/lars_grobe.vcf