[Radiance-general] Simulating Perforated Metal

[Peter Apian-Bennewitz]

dela wrote:
> 
> Hi everyone!
> 
> I'm trying to simulate perforated metal and would
> like to know if anyone knows of any examples where
> this has been done.  (or if this has been discussed
> in a previous digest)

Hi Mark,

good question:
I may take this nicely timed opportunity to announce that there's a
search engine running at http://www.radiance-online.org now.
Conveniently, it includes radsite.lbl.gov, so a check for "perforated"
gives a 1997 entry with some hints on using trans for this.
 
> I suppose one way to do it would be to have a metal
> plane and array a series of antimatter spheres which
> would subtract holes in the metal.  Seems like this
> would work, but is perhaps not the most efficient way
> to do this.
Could be done that way, but uses a lot of space and is prone to aliasing
effects. Only recommended if your viewpoint is the same order of
magnitude as the hole pattern. Further away, use trans to model the
average transmittance. If both is needed on one surface, you may want to
use mixfunc to blend between the two by view distance.

-Peter

-- 
 pab-opto, Freiburg, Germany, www.pab-opto.de