For now, this is my implementation of texture, pay attention on the reflection and refraction, it is considering the normal mapping.

Initial Ray differential propagation bug solution

Ray differential propagation is causing bug to the anisotropic filtering

Initial normal mapping implementation.

Everything as before, but using basic multisampling, because why not?

Added ray differentials, mipmaps and anisotropic filter. Not sure if the implementation is fully correct, but its filtering

Basic texture implementation.