ST_HillShade — Returns the hypothetical illumination of an elevation raster band using provided azimuth, altitude, brightness and elevation scale inputs. Useful for visualizing terrain.
raster ST_HillShade(raster rast, integer band, text pixeltype, double precision azimuth, double precision altitude, double precision max_bright=255, double precision elevation_scale=1);
Returns the hypothetical illumination of an elevation raster band using the azimuth, altitude, brightness, and elevation scale inputs. Utilizes map algebra and applies the hill shade equation to neighboring pixels.
The hill shade equation is:
max_bright * ( (cos(zenith)*cos(slope)) + (sin(zenith)*sin(slope)*cos(azimuth - aspect)) )
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Availability: 2.0.0