本代码几乎涵盖了所有GIS地图瓦片的常用算法：提供了当前多种互联网地图瓦片的索引算法（包括wgs84坐标、web墨卡托坐标、像素坐标、瓦片坐标）及其相互转换方法，包括google地图，微软bing地图等等。-This code covers almost all GIS map tiles commonly used algorithms: current Internet map tiles index algorithm (including wgs84 coordinates of web Mercator coordinates, pixel coordinates of the tile coordinates) and their mutual conversion method, including google map Microsoft bing maps.