Abstract: Three-dimensional visualization of water surface is an important technical means to achieve realistic display of digital watershed. The existing three-dimensional visualization technology of water surface generally does not consider the characteristics of water surface ratio of natural river course, and it is difficult to apply to three-dimensional visualization of water surface at large scale and basin level. A three-dimensional visualization method of river surface water surface considering water surface ratio is proposed. Firstly, boundary point densification and polygon triangulation were performed on the river surface boundary polygon, and then the elevation of the polygon boundary point was interpolated and adjusted based on the river water level process data. The adjusted triangle mesh was used for water surface drawing. Based on the water level process data of the Three Gorges reservoir area, the three-dimensional visualization of the river surface was carried out. The results show that the method can effectively express the water level grading process of natural rivers.

Key words: river surface, water surface slope, 3d visualization, triangulation, digital river basin, water surface interpolation