Search found 8 matches

by amaan
Sat Jan 07, 2012 10:12 am
Forum: General Development
Topic: Preetham Sun, spectral rendering
Replies: 15
Views: 11847

Re: Preetham Sun, spectral rendering

Thanks graphicsMan and tstanev. Good to confirm the integration bit.

Any more info on this lat-long dependence?
by amaan
Thu Jan 05, 2012 6:11 pm
Forum: General Development
Topic: Preetham Sun, spectral rendering
Replies: 15
Views: 11847

Re: Preetham Sun, spectral rendering

Hi all, At the risk of further embarrassing myself, here are a few more questions if you have time. I've seen the the Optix code and it's been helpful in tracking down the units issue. In the spectrum-to-XYZ conversion code, a multiplicative factor pops up again for (int i = 0; i < 38; ++i) { XYZ.X ...
by amaan
Mon Jan 02, 2012 6:40 pm
Forum: General Development
Topic: Preetham Sun, spectral rendering
Replies: 15
Views: 11847

Re: Preetham Sun, spectral rendering

OK just found the Optix SDK code (Haven't looked at optix at all before this)

...\OptiX SDK 2.1.1\SDK\sutil\SunSky.

Thanks,
Amaan
by amaan
Mon Jan 02, 2012 11:00 am
Forum: General Development
Topic: Preetham Sun, spectral rendering
Replies: 15
Views: 11847

Re: Preetham Sun, spectral rendering

tstanev, Cuneyt and apaffy, thank you so much for all these insights. I happened upon the Colorado LISIRD website a few days back but found that the SPD was not plotted over visible range. Was I just looking in the wrong place? And does anyone have the OPTIX code lying around for reference? Thanks a...
by amaan
Thu Dec 29, 2011 4:01 pm
Forum: General Development
Topic: Preetham Sun, spectral rendering
Replies: 15
Views: 11847

Re: Preetham Sun, spectral rendering

one quick question about the units for sun's radiance. The sample code that is available with the paper makes a correction by multiplying the radiance data by a factor of 100, citing incorrect units as also pointed about by Necro. What is the source of this discrepancy? The data that I am looking at...
by amaan
Thu Dec 22, 2011 3:01 pm
Forum: General Development
Topic: Preetham Sun, spectral rendering
Replies: 15
Views: 11847

Re: Preetham Sun, spectral rendering

thanks for the tips, necro.
by amaan
Tue Dec 20, 2011 8:36 pm
Forum: General Development
Topic: Preetham Sun, spectral rendering
Replies: 15
Views: 11847

Re: Preetham Sun, spectral rendering

Thanks for the help with the conversion and for confirming the attenuation values.
by amaan
Tue Dec 20, 2011 1:33 pm
Forum: General Development
Topic: Preetham Sun, spectral rendering
Replies: 15
Views: 11847

Preetham Sun, spectral rendering

Greetings everyone, This is my first post here, so a big Hello to you all. I have been a long time lurker at the ompf forum and just today discovered this place. I have been meaning to finish the 'Physical Sun' part of my implementation of the original Preetham paper. I am stuck on a few things so I...