2005 Reports

Approximating the Reflection Integral as a Summation: Where Did the dωi Go?

Ben-Artzi, Aner

In this note, I explore why the the common approximation of the reflection integral is not written with a delta omega-in ( ) to replace the differential omega-in ( ). After that, I go on to discover what really happens when the sum over all directions is reduced to a sum over a small number of directions. In the final section, I make recommendations for correctly approximating the reflection sum, and briefly suggest a possible framework for multiple importance sampling on both lighting and brdf.