对接他人提供的底图服务

然后是开发自己的底图服务，结构可以参考现成已有的

参考链接

https://xcsf.github.io/blog/2020/06/12/%E7%93%A6%E7%89%87Tile%E5%9C%B0%E5%9B%BE%E5%8E%9F%E7%90%86/ https://xcsf.github.io/blog/2020/06/12/%E7%93%A6%E7%89%87Tile%E8%A1%8C%E5%88%97%E5%8F%B7%E8%AE%A1%E7%AE%97%E6%96%B9%E6%B3%95/ https://github.com/RLwu/GIS https://switch2osm.org/using-tiles/getting-started-with-leaflet/ https://leafletjs.cn/ https://zh.wikipedia.org/wiki/%E9%BA%A5%E5%8D%A1%E6%89%98%E6%8A%95%E5%BD%B1%E6%B3%95 https://zh.wikipedia.org/wiki/Web%E5%A2%A8%E5%8D%A1%E6%89%98%E6%8A%95%E5%BD%B1 https://web.archive.org/web/20220421120137/https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames https://en.wikipedia.org/wiki/Web_Mercator_projection https://web.archive.org/web/20141009142830/http://earth-info.nga.mil/GandG/wgs84/web_mercator/(U)%20NGA_SIG_0011_1.0.0_WEBMERC.pdf https://www.openstreetmap.org/#map=15/22.7602/114.3888&layers=D https://en.wikipedia.org/wiki/Eccentricity_(mathematics)#:~:text=The%20eccentricity%20of%20an%20ellipse%20is%2C%20most%20simply%2C%20the%20ratio,of%20the%20semimajor%20axis%20a.&text=(Flattening%20may%20be%20denoted%20by,if%20f%20is%20linear%20eccentricity.)

http://wiki.gis.com/wiki/index.php/Geodetic_system https://developer.mozilla.org/zh-CN/docs/Web/API/CanvasRenderingContext2D/textBaseline https://developer.mozilla.org/zh-CN/docs/Web/API/CanvasRenderingContext2D/textAlign