The present function allows computation of local horizon due to surrounding terrain using a Digital Elevation Model tile defined by the user, and can be used, for example, for considering topography effects on solar radiation (shading effects --> "sun mask"). It is both faster and more accurate than the usual GIS tools. The present version only computes single horizons; the version dedicated to the integration of terrain effects into solar radiation and irradiation maps will follow as soon as possible.
For further information, please refer to the following article, where the underlying algorithm has been depicted and validated: "Pillot, B., Muselli, M., Poggi, P., Haurant, P., Dias, J.B., Development and validation of a new efficient SRTM DEM-based horizon model combined with optimization and error prediction methods, Solar Energy, 2016, vol. 129, pp. 101-115." (http://www.sciencedirect.com/science/article/pii/S0038092X16000827 and full-text available on ResearchGate). If you intend to publish any material using the present algorithm, please cite this work.
Full help documentation is available in main m-file "sunMask.m". Furthermore, for an example on how to use this function, see the "horizonExample.m" script in the /Example directory.

Bugs and suggestions:
Please send to Benjamin Pillot (benjaminfp at unisinos dot br)