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AcademySoftwareFoundation / OpenPBR

Specification and reference implementation for the OpenPBR Surface shading model
Apache License 2.0
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Definition of angle for F82 #87

Closed natyh closed 1 year ago

natyh commented 1 year ago

The specification says (in the comments on equation (43), that the angle for F82 is defined as 82 degrees. This is not accurate - the actual angle should be defined as arccos(1/7), which is close to but not exactly 82 degrees. In other words, mu_bar is defined as exactly 1/7. This is needed for the math to work out with integer powers, etc.

portsmouth commented 1 year ago

Thanks Naty, I will make a PR to fix up that mistake.

portsmouth commented 1 year ago

See https://github.com/AcademySoftwareFoundation/OpenPBR/pull/90

jstone-lucasfilm commented 1 year ago

Thanks for the fix, @portsmouth!