New Hosek and Wilkie sky model

[jeanphi]

Hi,

I've just added a new sky2 light using the Hosek and Wilkie model. All the code is mine, but the model and the data is theirs.
Please test it and let me know what you think of it.
EDIT: the current code doesn't yet allow to specify the earth albedo, but that will be a natural extension if you like it.

Reference: http://cgg.mff.cuni.cz/projects/SkylightModelling/

Jeanphi

[J the Ninja]

EDIT: Wait a sec, I just tried that in my 1.0 build and it gave the same result.


Does this work with the sunsky light or no?

[B.Y.O.B.]

Yay! Very cool

[cwichura]

What visual differences should be expected between this model and the existing one in Lux? A pros/cons of the two models would be useful to know.

[J the Ninja]

What visual differences should be expected between this model and the existing one in Lux? A pros/cons of the two models would be useful to know.

IIRC, new one gives much more realistic colors, especially when the sun is low on the horizon.

[J the Ninja]

Ok, after a quick refresher on the light syntax courtesy of LordCrc, I've managed to get a proper test for this.

And....is this right? This doesn't look right:


Sky1 (matches Lux 1.0 result):

Sky2:

[jeanphi]

Hi,

It's indeed looking wrong. I have also found some situations where I get this greenish look, or a black zenith area. I have yet to figure out what's going on since it is otherwise mostly working. Maybe it's due to the different interpolation I'm doing or a wrong angle computation somewhere. I'll try to make some automatic testing and comparison with the original code.

Jeanphi

[jeanphi]

Hi,

There was indeed a silly typo in my implementation, the new sky light is now behaving as expected (at least to the extent of my testing).

Jeanphi

[J the Ninja]

Ah, great to hear! I'll repeat my test when I get home tonight.

Btw, are there plans for a "sunsky2" lamp as well? It would make the implementation in LuxBlend26 a lot simpler.

[jeanphi]

Done

Jeanphi