Compared with traditional sightline based algorithms,the algorithm for computing viewsheds based on reference planes has no use for DEM interpllations,without redundance calculations.

• 与传统基于视线的可视域算法相比,利用参考面快速计算可视域算法不需进行DEM内插,无冗余计算,计算时间与视点位置和可视域面积无关,受DEM区域大小影响不