Based on ASTER-DEM data; Data denoising and reconstruction; According to the variation of terrain slope; Divided into 7 levels; They are: Level 1 (0-1 degrees); Level 2 (1-3 degrees); Level 3 (3-7 degrees); Level 4 (7-15 degrees); Level 5 (15-25 degrees); Level 6 (25-35 degrees); Level 7 (above 35 degrees); Data source（ https://geodoi.ac.cn/doi.aspx?doi=10.3974/geodb.2016.04.13.V1 ）
中心点纬度：47.906013
中心点经度：124.3366
最大缩放级别：9
最小缩放级别：0
Current zoom level：4