[Radiance-general] Problem with refraction in Dielectric material

[Greg Ward]

Hi Francesco,

Radiance doesn't compute "caustics" directly -- refractions of beam  
radiation through dielectric materials.  You can visualize the  
displacement of light rays by looking through a dielectric solid, but  
the beams of light will not be translated by default.  (It is possible  
to get such behavior using the prism types, but it's not provided as a  
default behavior because such modeling is expensive and not required  
by most architectural environments.)

Best,
-Greg

> From: francesco.frontini at polimi.it
> Date: August 20, 2009 5:58:39 AM PDT
>
> Dear all,
> I am running a simulation test to asses if Radiance calculates  
> correctly the refraction inside a dielectric material. (Snell law   
> n1*sin(A1) = n2sin(A2) ).
>
>
> I build up two identical geometry one with a dielectric pane and the  
> second without. The direct light can pass through a gap between two  
> plastic surfaces.
>
>
> Using just direct calculation (sun) I should have two identical  
> bright stripes in dimension but the one passing through the  
> dielectric panel should be shifted due to the refraction in the  
> dielectric pane.
>
> ....
>
>
> Any comment or idea are appreciated
>
> Regards
> Francesco