[Radiance-general] Radiance Vs Viz

[Peter Apian-Bennewitz]

Mark de la Fuente wrote:

> I've been having a discussion with the people at my office about the 
> differences between Radiance and 3D Studio Viz & Lightscape.  (They 
> are used to using Lightscape and don't know anything about Radiance)  
> And I was hoping some of you might have some comparison or contrasting 
> comments on this subject since I'm sure most of you have had some 
> experience with this sort of discussion.

Hi Mark,
there's a 2001 Lightscape/Radiance comparison at  
http://www.pab-opto.de/  , although it would be worth redoing the calcs 
with Radiance+photonmap, to show the differences clearly.

>  Even though we are specifically talking about Radiance Vs Lightscape 
> & Viz, I think this is in part more a comparison about radiosity Vs 
> raytracing.  From what I know, the big problem with radiosity is that 
> it simplifies things and assumes lambertian reflections.  This is 
> obviously a deviation from reality, but I assume it's still possible 
> to achieve a pretty accurate calculation of some sort depending on the 
> situation.  ...

Most materials show a specular peak at low incident angle.  Interesting 
materials for light redirection are  non-lambertian, starting with 
simple structures like outside louvers.
-Peter

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 pab-opto, Freiburg, Germany, http://www.pab-opto.de
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