For a given elevation dataset, create a terrain occlusion mask.
The terrain occlusion mask is a multi-step process that identifies pixel occlusion by the surrounding terrain (cast shadow) from two different viewing sources (solar and satellite/observer), as well as pixels that exhibit shadow unto itself (self shadow).
A pixel is determined to be shaded if it is not viewable by:
- The satellite (observer)
- The sun
The pixel doesn't receive direct radiation as the surface faces away from the sun.
The algorithm is based on:
Giles, P.T.. (2001). Remote sensing and cast shadows in mountainous terrain. Photogrammetric Engineering and Remote Sensing. 67. 833-839.