光学推导

[kanition]

Fresnel's Equations for Reflection and Transmission
https://www.brown.edu/research/labs/mittleman/sites/brown.edu.research.labs.mittleman/files/uploads/lecture13_0.pdf

[kanition]

An Anisotropic Phong Light Reflection Model

For

Fresnel-based reduced diffuse reflection in a physically plausible manner

From #159

[kanition]

Refer: Optics section4.6 Fresnel Equations