[Radiance-general] 5Phase & proxy geometry

Tue Nov 5 05:57:56 PST 2013

Hi Andy

I thank you for the pdf  files and I'll send you then the xml file so you
can have a look to it. Thanks also for that!

Chantal

2013/11/4 Andrew McNeil <amcneil at lbl.gov>

> Hi Chantal,
> You should be able to use a non-klems and non-tensor tree BSDF as long as
> the angle basis can be described using the format described in the XML
> schema (not all can - I've maintain hacked version of Radiance to use a
> BSDF angle basis that I've developed). If you send me the XML file I can
> look to see what could be causing the problem.
>
> Yes, there are tools for resampling BSDF files.
> bsdf2klems :
> http://www.radiance-online.org/learning/documentation/manual-pages/pdfs/bsdf2klems.pdf
> bsdf2ttree :
> http://www.radiance-online.org/learning/documentation/manual-pages/pdfs/bsdf2ttree.pdf
>
>  Andy
>
>
>
>
> On Sun, Nov 3, 2013 at 8:53 AM, minchaca <miinchaca at gmail.com> wrote:
>
>> Hi Andy
>>
>>
>>
>> Thanks a lot for your help with all my questions. I found the solution to
>> the last one... (Not really worth mentioning!!)
>>
>>  :))
>>
>>
>>
>> Regarding my previous 1st. Question:
>>
>>
>>
>> I tried to create a *glazing_bsdf.rad* file using one of the cfs.xml
>> files that we have in the lab. I’ve got the message:
>>
>> “Unsupported IncidentDataStructure for BSDF”, I assume this means that
>> this is not a ‘tensor tree high resolution BSDF”.
>>
>> This might be a silly question but: if there is a way to resample the
>> tensor tree BSDF into a Klems basis BSDF, is there any way
>>
>> to do the other way around? Or...perhaps this 'error message' means
>> something else..?
>>
>>
>>
>> I thank you in advance for your help again!!
>>
>>
>>
>> Chantal.
>>
>>
>> 2013/11/1 Andrew McNeil <amcneil at lbl.gov>
>>
>>>  Hi Chantal,
>>>
>>> 1.- I’m not sure of the use of the ‘BSDFproxy polygon inside’ included
>>>> in the glazing_bsdf.rad file.
>>>>
>>> The BSDF material is applied to this surface. It allows Radiance to use
>>> the BSDF data in lieu of sampling the geometry during the direct sun
>>> simulation.
>>>
>>>
>>>> If the latter was generated by genBSDF and includes already the
>>>> dimensions of the venetian blind, the model, the glazing, and the thickness
>>>> is also specified…why do we need to specify the coordinates of the polygon
>>>> (same of the glow material) in this file?
>>>>
>>> The BSDF is not always produced by genBSDF, it can come from WINDOW or
>>> from measurement as well. But regardless, the intention is that optical
>>> data in a BSDF file is not specific to a size of window, and so you could
>>> use it in various sized windows.  For example if lightlouver produces a
>>> BSDF for their product using genBSDF for one project you might want to use
>>> it in a 2m window for one project but a 3m window for another. Addtionally
>>> there may be times when you want to use a different thinckness for the
>>> simulation.  I can think of probably half a dozen reasons why you might not
>>> want to use dimensions baked into a BSDF file, an as is typical with
>>> Radiance we lean towards generalization.
>>>
>>>
>>>>
>>>>
>>>> I also wonder if we need to use proxy when only if we have a system
>>>> such as venetian blinds. Is possible to use it also if we have a daylight
>>>> system as thick as a glass pane such as lasercut panel 6mm?
>>>>
>>> Yes, but it isn't worth it unless you have a good Radiance material
>>> model for the lasercut panel.  Otherwise you're better off using the BSDF
>>> (assuming it was measured).
>>>
>>>
>>>>
>>>>
>>>> I guess that I can shorten this question by: what would be exactly the
>>>> function of the proxy geometry?
>>>>
>>> The BSDF, even high resolution tensortree BSDFs, are spatially averaged.
>>>  A venetian blind that is angled to admit stripes of light modeled with
>>> only a BSDF will result in a rectangular patch of intermediate brightness.
>>>  Using proxy geometry results in bright sun alternating with dark shadows.
>>>
>>>>
>>>>
>>>> 2.- Regarding this, in the tutorial you have to rotate the geometry in
>>>> order to generate the two xml files (section 6.2) my
>>>> silly-silly-super-silly question is:  what would be the orientation of
>>>> the resulting xml file? Are we re-orientating it by the last three values
>>>> of the orientation vector in the glazing_bsdf.rad ?
>>>>
>>> The WINDOW XML file standard says inside is +Z outside is -Z, up is +Y.
>>>   In Radiance we use up as +Z and inside and outside, well it depends on
>>> the space your modeling.
>>>
>>>
>>>>
>>>>
>>>> 3.- I have a final question that just came now when trying the 5Phase:
>>>> What would be the number to use in rcontrib –bn when creating the
>>>> direct-sun-coefficient-matrix?
>>>>
>>>> As I understand, it represents the number of sky patches, and it will
>>>> generate the values of the RGB in the output file. But, if I use –e MF:6 –f
>>>> reinhart.cal –b 5186, I obtain a matrix result with 31116 columns, which is
>>>> the number of sky patches six times? Please tell me where am I wrong.
>>>>
>>>
>>> There should be three values per skypatch (R G and B) I don't know why
>>> you are getting twice as many.  Can you send the full command you are using?
>>>
>>> Andy
>>>
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> Radiance-general mailing list
>>> Radiance-general at radiance-online.org
>>> http://www.radiance-online.org/mailman/listinfo/radiance-general
>>>
>>>
>>
>> _______________________________________________
>> Radiance-general mailing list
>> Radiance-general at radiance-online.org
>> http://www.radiance-online.org/mailman/listinfo/radiance-general
>>
>>
>
> _______________________________________________
> 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/20131105/eff918cb/attachment.html>