Putting it all together: BRDFs, Object Lights and Path Tracing
Putting It All Together: BRDFs, Object Lights and Path Tracing In this post I will explain three concepts that are very very important for ray tracing but easy to implement concepts relative to their importance (they still need care though). Bidirectional Reflection Distribution Functions (AKA BRDFs) Let us remember the reflectance term of the rendering equation. The f here is the brdf function. Up to now I was doing using a model called the Blinn-Phon shading model. Actually this is not the only shading model we can use and we should use them because in real life we have different all kinds of materials. This is where the Bidirectional Reflection Distribution Functions come in. We can think of them as a an abstract interface for all the shading models. Figure 1: Rendering hemisphere [1] These functions takes 3 arguments: the point x that is being shaded, the incoming light ray direction wi, the outgoing (eye) ray direction wo and returns the amount of light that is refl...