[Radiance-general] different methods on irradiance calculation

[Ali Fatoorechi]

Hi Guys,

I am writing mainly to understand Radiance more on different methods on
irradiance calculation on surface point while maintaining accuracy and
speed.

- I can use rtrace with irradiance interpolation turned on and rely on high
-ad( >1024) for direct light from sky.
running Radiance on Windows, it didn't seem to do run it in multi
processing(-n). I am not sure if this is supported on Windows?
Also breaking the points in chunks and running separate rtrace processes
didn't seem to speed it up much.
I don't go mad with -a numbers but the time tends to increase, sometimes up
to an hour for a room on complex models.

- I tried mkillum to increase the speed/accuracy but as the model is all
triangles I get the "aiming failure" error messages,
 and it was mentioned in another post that triangles are poor choice for
light sources(due to the way Radiance samples
direct lighting.) I guess mkillum may not be advised in this case? also the
calc time increases linearly with with more illums in the model.

- rtrace with interpolation switched off, seems to be pretty quick. but as
it is blind monte carlo there is a concern on accuracy on
direct lighting I guess(unless using high -ad). I have seen the window
glazing defined as glow in three phase method(and later to use genbsdf for
T).
I am not quite familiar but if glow material is part of the direct
lighting, would this make it a better approach than pure MC?

thanks and apology for this long post,
Ali
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.radiance-online.org/pipermail/radiance-general/attachments/20170411/e480c9cc/attachment.html>