Sigma?
Re: Sigma?
the roughness of the surface, basically more backscattering == flatter looking.
for more information and examples, google "oren nayar" and check the first hit.
for more information and examples, google "oren nayar" and check the first hit.
Re: Sigma?
I found this in the Technical manual the other day:
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- Example of sigma levels
- sigma.jpg (84.15 KiB) Viewed 4432 times
- Borgleader
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- Polinalkrimizei
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Re: Sigma?
The above pictures make no sense to me. Sigma = 0 in the wikipedia article looks like Sigma = 1 in the technical manual. According to wikipedia, a higher value for sigma makes the model look more flat, but with indigo it looks flattest with the lowest sigma setting.
Is it just me? Or did something get mixed up?
Is it just me? Or did something get mixed up?
- Borgleader
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Re: Sigma?
Is it possible ono somehow implemented the function...backwards?Polinalkrimizei wrote:The above pictures make no sense to me. Sigma = 0 in the wikipedia article looks like Sigma = 1 in the technical manual. According to wikipedia, a higher value for sigma makes the model look more flat, but with indigo it looks flattest with the lowest sigma setting.
Is it just me? Or did something get mixed up?
benn hired a mercenary to kill my sig...
Re: Sigma?
It just depends where the light comes from - sigma increases backscattering.Polinalkrimizei wrote:The above pictures make no sense to me. Sigma = 0 in the wikipedia article looks like Sigma = 1 in the technical manual. According to wikipedia, a higher value for sigma makes the model look more flat, but with indigo it looks flattest with the lowest sigma setting.
Is it just me? Or did something get mixed up?
Re: Sigma?
i got the same impression; the wiki images are in line with my expectations.Polinalkrimizei wrote:The above pictures make no sense to me. Sigma = 0 in the wikipedia article looks like Sigma = 1 in the technical manual. According to wikipedia, a higher value for sigma makes the model look more flat, but with indigo it looks flattest with the lowest sigma setting.
Is it just me? Or did something get mixed up?
anyone wanna render some spheres?
Re: Sigma?
like the wikipedia image. 0, 0.1, 0.3
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- sigma.jpg (26.28 KiB) Viewed 4328 times
Re: Sigma?
I wasn't either under the same impression than you, polin and lyc. Higher sigma seems to darken the surface, however if you observe closer you can see that the dark rim edges are also fading away, see below.
I'm fine with the actual implementation
I'm fine with the actual implementation
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- diffuse - 0.0 - 0.2 - 0.5 - 1.0
- ON_test.jpg (58.29 KiB) Viewed 4304 times
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- PureSpider
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Re: Sigma?
While on the "topic"...
Can the Torrance-Sparrow model for Phong be implemented, Ono?
Or is it too much of a hassle?
Can the Torrance-Sparrow model for Phong be implemented, Ono?
Or is it too much of a hassle?
- Polinalkrimizei
- Posts: 647
- Joined: Sat May 02, 2009 6:59 am
Re: Sigma?
Thanks for the clarification guys.
CTZn, your image made it pretty clear and now I think I got it!
CTZn, your image made it pretty clear and now I think I got it!
Re: Sigma?
clearly visible the higher the sigma the darker the material gets!
This is something I never understood...
(About my old Statue render on the top... simply drag & Drop the image into a new Firefox Tab to see it in Full size Neo, the forum scales images down!)
This is something I never understood...
(About my old Statue render on the top... simply drag & Drop the image into a new Firefox Tab to see it in Full size Neo, the forum scales images down!)
polygonmanufaktur.de
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