This equation is easy to understand, but how can we implement it? We need to go through all directions in the code?
Do we have pre-defined scatter function for daily texture?
This is an important slide for A3 task 5 :D
Shouldn't this dwi is the solid angle of the hemisphere around the light source? But according to the equation, it is the solid angle of photon hit point.
Nevermind. I might misunderstood the concepts. I treat solid angle more like an " unit area" in sphere than a set of "direction". In this case, I was confused by which sphere is this "unit area" refers to.