[Radiance-general] BSDF orientation and implementation

[Andrew McNeil]

Chris,
Everything you write seems correct. One whatch-it I can offer is to make
sure you're system is situated properly for the genBSDF run. +Z is into the
space, +Y is up.  All of the geometry should be in the -Z space. If you
don't follow these guidelines you're BSDF will be strange.
Andy


On Tue, Feb 25, 2014 at 8:06 AM, Chris Coulter <
Chris.Coulter at burohappold.com> wrote:

>  Good morning Gurus!
>
>
>
> I have worked through the 3- and 5-phase tutorials in hopes of being able
> to apply a BSDF to one of my projects. This project will be using
> micro-louver cellular structures imbedded within an IGU, in both skylights
> and vertical windows. I think I understand the general process, but wanted
> to ask a few questions before getting too far down the road...
>
>
>
> The skylights and windows are all different sizes and the windows are in
> multiple orientations (of course). My understanding of the BSDF and
> seemingly from this mail (
> http://www.radiance-online.org/pipermail/radiance-general/2011-November/008248.html),
> I should be able to calculate the BSDF once for my system. I was planning
> model the louvers as 1m by 1m, but run genBSDF with the -dim arguments
> smaller than this. Is this the correct approach? Ideally I would not
> calculate the BSDF for each orientation, assuming that micro-louver
> geometry does not change.
>
>
>
> In my BSDF material definition, I would alter the up vector according to
> the surface being applied - the up vector matches the BSDF orientation
> (calculated in xy space) to the specific geometry's orientation (0 0 1 for
> a window). If the louver are rotated within the IGU assembly (rz -45) for a
> skylight, I can account for this with the up vector of 1 1 0 (surface
> normal is 0 0 1). This would hold true for rotation within the vertical
> apertures as well. Each different up vector would be a different BSDF
> material.
>
>
>
> Lastly, if the glazing properties (VLT) are not defined yet, can I import
> the BSDF file into Window and create multiple options for IGU's with
> varying properties? It seems so from David Geisler-Moroder's presentation
> at the 2012 Workshop (
> http://radiance-online.org/community/workshops/2012-copenhagen/Day1/Geisler-Moroder/geisler-moroder_BSDF_tutorial_s.pdf).
> Certainly skylights and windows will have different VLT and it would again
> be nice to not be required to run genBSDF multiple times.
>
>
>
> I am in the process of working through the steps on my own, but wanted to
> ask these questions while I'm waiting on genBSDF.
>
>
>
>
>
> Any help is much appreciated, as always.
>
>
>
> *Chris Coulter*
>
> *Senior Lighting Designer*
> Buro Happold Consulting Engineers
>
> 100 Broadway, 23rd Floor
>
> New York, NY 10005
>
> Tel: 212.334.2025
>
> Direct: 212.616.0254
>
> Email: chris.coulter at burohappold.com
>
> Website: www.burohappold.com
>
>
>
> _______________________________________________
> Radiance-general mailing list
> Radiance-general at radiance-online.org
> http://www.radiance-online.org/mailman/listinfo/radiance-general
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.radiance-online.org/pipermail/radiance-general/attachments/20140225/c937fc6e/attachment.html>