Vessel can not be regarded as particle while vessel is berthing,so distance of vessel and shoreline is not distance of point and line,it should be calculated as space between polygon and line.

• 在船舶靠泊操纵仿真中,由于船舶不能视为质点运动,因此船岸距离的计算不能简单地归结为点线距离,而应该用多边形间距方法进行计算。