AcademySoftwareFoundation / AcademySoftwareFoundation/OpenPBR
Add formula for the average albedo of the F82-tint model
- Dominant language
- CSS
- Stars
- 793
- Forks
- 44
- PR merge metrics
- No merged PRs in 30d
Description
It is possible to analytically calculate the average albedo of the F82-tint model used for metal reflectivity in OpenPBR. Specifically, the average Fresnel can be calculated by integrating the reflectivity over the cosine-weighted hemisphere.
The average Fresnel is very useful to more accurately tint the multiple-scattering component of the rough metal surface. So I propose that we include this formula in the spec.
Contributor guide
No contributing guide indexed for this repository
Research direction
Start by reading the OpenPBR specification sections covering the F82-tint model, metal reflectivity, and multiple scattering. Verify the cosine-weighted hemisphere integration for the average Fresnel, then update the specification when the formula and its use for tinting are unambiguous.
Written by the indexing model from the issue text.
Assessment
- Domain
- computer-graphics, documentation
- Issue type
- Documentation
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100