Image-Space Horizon-Based Ambient Occlusion

@incollection{bavoil2008image,
  title={Image-space horizon-based ambient occlusion},
  author={Bavoil, Louis and Sainz, Miguel and Dimitrov, Rouslan},
  booktitle={ACM SIGGRAPH 2008 talks},
  pages={1--1},
  year={2008}
}