[Radiance-general] glass modifier under different angles

[Greg Ward]

Hi Lars,

The 'glass' type correctly computes the angular transmittance and  
reflectance of any sheet of glass, since the actual thickness drops  
out of the equation.  The only thing it won't do for you is show  
double- and triple- reflections that are offset by the glazing  
thickness, as one might notice in a thick pane of glass.

-Greg

> From: "Lars Oliver Grobe" <akilog at nus.edu.sg>
> Date: January 14, 2009 2:17:40 AM PST
>
> Hi Thomas, thank you for the reply!
>
> Yes, I know that it is an optimization. Still it would be possible to
> account for the angular dependent distance given a single polygon  
> if you
> rely on that average of about 6mm. But the internal calculation should
> include the angular dependency than, and that is what I am  
> wondering. So
> is the fact that a ray entering a glass face at 0 degree  
> (perpendicular)
> would travel a much shorter distance through the material then one
> hitting it at 45 degree considered in the glass modifier code?
>
> BTW yes I think this is explained in RwR, though I do not know if this
> question is answered there. Unfortunately my book is 10.000km from my
> current location and the one we ordered weeks ago seems to be not
> available.
>
> CU Lars.