Lesson 8: Ambient occlusion
In previous lectures we used local illumination model. In other words, for computing illumination of a current pixel we did not take into account its neighbors. Phong reflection model is a famous example of such approach:
In this model final illumination intensity for a point is a sum of three components: ambient intensity, constant for all points in the scene, diffuse and specular highlights depending on normal vectors. Wait a minute, why did he choose constant ambient component?
Well, I was not 100% right: we did use a bit global illumination when we computed shadow mapping. Let us check another possibility to improve our renders (note that one does not exclude another!). Here is an example where I used only ambient component of the Phong reflection model:
No diffuse component, no specular. Ambient only, however it is easy to see that I did not choose it to be constant.
