得到高德地图的每个瓦片四至

我想得到高德地图每个加载的了的瓦片的四至或者是每个层级的属性!已经拿到了瓦片宽度.
####对标的天地图层级属性

懂的都懂不做解释了唉

_

```javascript
http://www.javashuo.com/article/p-aytixtxw-ec.html可以得到比例尺和相对应的级别?
//天地图对应的
 tileInfoWeb: {
        dpi: 96,
        rows: 256,
        cols: 256,
        compressionQuality: 0,
        origin: {
          x: -20037508.3427892,
          y: 20037508.3427892
        },
        spatialReference: {
          wkid: 3857
        },
        lods: [
          {
            level: 2,
            levelValue: 2,
            resolution: 39135.75848201024,
            scale: 147748796.52937502
          },
          {
            level: 3,
            levelValue: 3,
            resolution: 19567.87924100512,
            scale: 73874398.264687508
          },
          {
            level: 4,
            levelValue: 4,
            resolution: 9783.93962050256,
            scale: 36937199.132343754
          },
          {
            level: 5,
            levelValue: 5,
            resolution: 4891.96981025128,
            scale: 18468599.566171877
          },
          {
            level: 6,
            levelValue: 6,
            resolution: 2445.98490512564,
            scale: 9234299.7830859385
          },
          {
            level: 7,
            levelValue: 7,
            resolution: 1222.99245256282,
            scale: 4617149.8915429693
          },
          {
            level: 8,
            levelValue: 8,
            resolution: 611.49622628141,
            scale: 2308574.9457714846
          },
          {
            level: 9,
            levelValue: 9,
            resolution: 305.748113140705,
            scale: 1154287.4728857423
          },
          {
            level: 10,
            levelValue: 10,
            resolution: 152.8740565703525,
            scale: 577143.73644287116
          },
          {
            level: 11,
            levelValue: 11,
            resolution: 76.43702828517625,
            scale: 288571.86822143558
          },
          {
            level: 12,
            levelValue: 12,
            resolution: 38.21851414258813,
            scale: 144285.93411071779
          },
          {
            level: 13,
            levelValue: 13,
            resolution: 19.109257071294063,
            scale: 72142.967055358895
          },
          {
            level: 14,
            levelValue: 14,
            resolution: 9.554628535647032,
            scale: 36071.483527679447
          },
          {
            level: 15,
            levelValue: 15,
            resolution: 4.777314267823516,
            scale: 18035.741763839724
          },
          {
            level: 16,
            levelValue: 16,
            resolution: 2.388657133911758,
            scale: 9017.8708819198619
          },
          {
            level: 17,
            levelValue: 17,
            resolution: 1.194328566955879,
            scale: 4508.9354409599309
          },
          {
            level: 18,
            levelValue: 18,
            resolution: 0.5971642834779395,
            scale: 2254.4677204799655
          }
          // { level: 19, levelValue: 19, resolution: 0.298582141738970, scale: 1127.23386023998275 },
          // { level: 20, levelValue: 20, resolution: 0.298582141738970 / 2, scale: 1127.23386023998275 / 2 },
          // { level: 21, levelValue: 21, resolution: 0.298582141738970 / 4, scale: 1127.23386023998275 / 4 }
        ]
      },

```_