[Radiance-general] optics5

[Daniel LASH(SED)]

Hello,

Just a quick query about generating windows in Optics5.  I have created a simple double glazed
configuration of two 6mm layers of generic clear glass (the system is therefore symetrical i.e.
optical properties are congruent for front and back).  The export as a rad file (named 'roofglass')
creates a glass material and 2 brtdf materials (for front and back).  Which should I use, the
glass, or one of the BRTDFs?  They return slightly differing results.  Is there a way of combining
the all 3 somehow to get one BRTDF that covers front and back (and which is front and back anyway,
front outside, back inside, assuming surface normals have been oriented inwards??).  The rad file
looks like this;

#
# FileName= GlzSys.usr
# Product Name= 
# NFRC ID= 30000
# Manufacturer Name= User
# Glazing Type= Glazing system
# Coated Side= Neither
# Transmittance= 0.785
# Front Reflectance= 0.144
# Back Reflectance= 0.144
# Thickness(mm)= 23.430
# Appearance= 
#


void  glass       roofglass_glazing
0
0
3     0.807     0.875     0.849

void  BRTDfunc    roofglass_front
10
      0.134     0.147     0.147
      0.740     0.803     0.779
      0 0 0
      .
0
9 0 0 0 0 0 0 0 0 0

void  BRTDfunc    roofglass_back
10
      0.134     0.147     0.147
      0.740     0.803     0.779
      0 0 0
      .
0
9 0 0 0 0 0 0 0 0 0


many thanks

Dan