百度地图自身有17个级别，如下：

{"20m","50m","100m","200m","500m","1km","2km","5km","10km","20km","25km","50km","100km","200km","500km","1000km","2000km"}

但是，提供的开发包只支持16个级别， Level: 3~18, 比例尺如下:

{"50m(18)","100m(17)","200m(16)","500m(15)","1km(14)","2km(13)","5km(12)","10km(11)","20km(10)","25km(9)","50km(8)","100km(7)","200km(6)","500km(5)","1000km(4)","2000km(3)"}

strong text百度影像缩放和谷歌地球差距还是很大的，自己没有星星就是搞不过