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OSplugin - Sky models and distribution

asked 2018-11-22 09:18:40 -0600

NunoSaraiva gravatar image

updated 2018-11-22 12:55:55 -0600

Hello everyone, I did a Radiance simulation with OS plugin and I am interpreting the code generated:

Info: oconv materials\materials.rad model.rad skies\dc_sky.rad skies\dc_sky.rad > octrees\model_WG0.oct

Info: type numeric\merged_space.map | rcontrib -ab 10 -ad 65536 -as 512 -dj 1 -dp 1 -dt 0 -dc 1 -lw 1.52e-05 -I+ -fo -e MF:1 -f tregenza.cal -b tbin -bn Ntbins -faa -o output\dc\WG0.vmx -m skyglow octrees\model_WG0.oct

Info: gendaymtx -m 1 "wx\in.wea" > annual-sky.mtx

Info: dctimestep output\dc\WG0.vmx annual-sky.mtx | rmtxop -fa -c 47.4 120 11.6 - > output\ts\WG0.ill

Info: rmtxop -fa> output\ts\WG0.ill -t | getinfo - > output\merged_space.ill

I have some questions:

why does in oconv the dc_sky. rad is duplicated?

also, according to Mardaljevic (PhD thesis) this file (dc_sky.rad) is a description of a uniform sky but then later we use gendaymtx to produce annual sky models (Perez models), does this information conflict with one in dc_sky.rad? From my understanding Perez models produce sky conditions over the year (clear, overcast, etc).

if i want to add more sky patches in gendaymtx (-m 4) do I need to change rcontrib trengeza.cal?

Thank you in advance for your time.

Best regards

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answered 2018-11-23 10:51:57 -0600

why does in oconv the dc_sky. rad is duplicated?

It should only be there once, but there is no negative effect of duplicating it. Rays going to infinity will only encounter one source, even if two are present.

does this information conflict with one in dc_sky.rad?

The content of the sky does not matter for rcontrib calculations. It only needs to be there as a source so that rcontrib can test whether or not it is seen by (i.e. contributes to) each ray.

if i want to add more sky patches in gendaymtx (-m 4) do I need to change rcontrib trengeza.cal?

Yes. You would instead use reinhart.cal with -e MF:4. If you have a separately defined ground surface and want to test for that as well, then use reinhartb.cal and include separate arguments for that (e.g. -b 0 -bn 1 -m ground) before specifying any arguments related to the sky.

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Asked: 2018-11-22 09:18:40 -0600

Seen: 68 times

Last updated: Nov 23