Schlick Approximation back
(L) [2007/07/03] [monkeyman] [Schlick Approximation] Wayback!Hi
I found this yesterday night on wikipedia: [LINK http://en.wikipedia.org/wiki/Schlick]'s_approximation
I understood that it was a similar thing to frensel, just with much less computation?
Sadly I can't try it to find out. Has anyone else heard of it?
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(L) [2007/07/03] [Michael77] [Schlick Approximation] Wayback!This approximation is pretty much always used in a realtime context since the "correct" fresnel computation is much more complicated.
(L) [2007/07/03] [monkeyman] [Schlick Approximation] Wayback!okay I never heard of it [SMILEY Razz]
DO the RTRT people use it?
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MacBook Pro
Core Duo 2 2.4ghz each,
2 Gigs Ram 667 Mhz,
800 Mhz FSB
(L) [2007/07/03] [greenhybrid] [Schlick Approximation] Wayback!Don't know if they do, but as in e.g. [LINK http://www.cs.utah.edu/~shirley/papers/pg97.pdf A PractitionersÂ’ Assessment of Light Reflection Models] (Shirley, Smits, Lafortune, Hu; found at Pete Shirley's graphics blog), in rendering systems, that don't take into account polarization, using Schlicks approximation will introduce less error than using the Fresnel equations.
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[LINK http://greenhybrid.net/ greenhybrid.net]
Real Men code Software Graphics.
(L) [2007/07/05] [lmv] [Schlick Approximation] Wayback!I've played a bit with this.
Maybe someone can find visual difference, but for me it looks very realistic.
At least I'm pretty happy with it [SMILEY Very Happy]
For dielectrics - [LINK http://xolmc.sbn.bz/gallery/mat/5_4.jpg]
For metals - [LINK http://xolmc.sbn.bz/gallery/mat/skull_bot_metal.jpg]
Sorry, right now can't find some glass pictures to show its impact on refraction [SMILEY Crying or Very sad]
(L) [2007/07/05] [monkeyman] [Schlick Approximation] Wayback!looks good [SMILEY Razz]
hm I am gonna implement both frensel and schlick approximation.
Why does polarization influence it so much...
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MacBook Pro
Core Duo 2 2.4ghz each,
2 Gigs Ram 667 Mhz,
800 Mhz FSB
(L) [2007/07/05] [greenhybrid] [Schlick Approximation] Wayback!Actually not too much. For the visual and intuitive appearance of an image, it doesn't matter in general. But there are a few special cases where it is needed, e.g. physics simulation (e.g. sensor systems, grabbed that example from the above mentioned [LINK http://www.cs.utah.edu/~shirley/papers/pg97.pdf A PractitionersÂ’ Assessment of Light Reflection Models], in my eyes (and I think in Pete Shirley's (on whoms blog I spotted it), too) that paper is a little gem).
edit: link paste.
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[LINK http://greenhybrid.net/ greenhybrid.net]
Real Men code Software Graphics.
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