# pbrMaterial (Shader Module)

Implements Physically Based Shading of a microfacet surface defined by a glTF material.

Lighting is expected to be defined by the `lights` module.


## References

- [Real Shading in Unreal Engine 4](http://blog.selfshadow.com/publications/s2013-shading-course/karis/s2013_pbs_epic_notes_v2.pdf)
- [Physically Based Shading at Disney](http://blog.selfshadow.com/publications/s2012-shading-course/burley/s2012_pbs_disney_brdf_notes_v3.pdf)
- [README.md - Environment Maps](https://github.com/KhronosGroup/glTF-WebGL-PBR/#environment-maps)
- ["An Inexpensive BRDF Model for Physically based Rendering" by Christophe Schlick](https://www.cs.virginia.edu/~jdl/bib/appearance/analytic%20models/schlick94b.pdf)

## Attribution

This implementation of PBR (Physically-Based Rendering) is a fork of the [Khronos Reference Implementation](https://github.com/KhronosGroup/glTF-WebGL-PBR) under the Apache 2.0 license.