| 摘要 |
A computer-implemented method for creating an image that depicts shadowing for a specified light source even though the input data is not three-dimensional and is limited to elevation data that associates an elevation value with each of a plurality of spatial coordinates. Plumb line walls are generated between elevation points of neighboring grid cells for each elevation point meeting a specified delta elevation criterion. A shadow map is accumulated based on visibility of each pixel to the light source position, and then, in a subsequent pass through the coordinate pixels of the data, an image is created in a tangible medium with each pixel correspondingly visible or shadowed, either totally or partially. Values along one dimension may be spread over a Z-buffer range to optimally resolve visibility features. |
