Abstract: A computer-implemented method for creating a shadow mask representing irradiation of a physical scene based upon a plurality of elevation grid points of an array of elevation data associated with the physical scene. Elevation point data are received and stored in array format and a shadow frontline is propagated across the array based on a quadrant associated with a light source. A shadow horizon is projection onto successive lines of elevation data generating a binary shadow mask based on whether a specified elevation point lies above or below the shadow horizon. The direction of the light source may be transformed to reflect curvature of an underlying surface of the physical scene.

Abstract: A computer-implemented method for creating a shadow mask representing irradiation of a physical scene based upon a plurality of elevation grid points of an array of elevation data associated with the physical scene. Elevation point data are received and stored in array format and a shadow frontline is propagated across the array based on a quadrant associated with a light source. A shadow horizon is projection onto successive lines of elevation data generating a binary shadow mask based on whether a specified elevation point lies above or below the shadow horizon. The direction of the light source may be transformed to reflect curvature of an underlying surface of the physical scene.