做地理信息系统（GIS）项目，除了实现功能用户体验度要好之外，最重要的是地图渲染效果更要好。很多时候苦于数据的完整性和对于配图的审美观，程序猿们都很难配出好看的地图效果。基于上述一般直接调用google的地图服务，包括矢量地图，地形地图和影像地图。这样就不用花大力气关注于数据的问题，只需要把地图的操作功能实现就行。下面来说说如何基于arcgis js api 调用google的地图服务。
首先我们需要知道google地图服务的地址：
http://mt.google.cn/vt/lyrs=s@112&hl=zh-CN&gl=cn //卫星地图服务
http://mt.google.cn/vt/lyrs=h@177000000&hl=zh-CN&gl=cn //地区名称矢量地图服务
http://mt.google.cn/vt/lyrs=m@112&hl=zh-CN&gl=cn //矢量地图服务
jsapi 初始化google地图服务实现代码：
initGoogleMapLayer:function(){
dojo.declare("GoogleMapLayer", esri.layers.TiledMapServiceLayer, { // create WMTSLayer by extending esri.layers.TiledMapServiceLayer
constructor: function(){
this.spatialReference = new esri.SpatialReference({
wkid: 102113
});
this.initialExtent = new esri.geometry.Extent(-20037508.342787, -20037508.342787, 20037508.342787, 20037508.342787, this.spatialReference);
this.fullExtent = new esri.geometry.Extent(-20037508.342787, -20037508.342787, 20037508.342787, 20037508.342787, this.spatialReference);
//
this.tileInfo = new esri.layers.TileInfo({
"dpi": "90.71428571427429",
"format": "image/png",
"compressionQuality": 0,
"spatialReference": {
"wkid": "3857"
},
"rows": 256,
"cols": 256,
"origin": {
"x": -20037508.342787,
"y": 20037508.342787
},
// Scales in DPI 96
"lods": [{"level": 0,"scale": 591657527.591555,"resolution": 156543.033928
}, {"level": 1,"scale": 295828763.795777,"resolution": 78271.5169639999
}, {"level": 2,"scale": 147914381.897889,"resolution": 39135.7584820001
}, {"level": 3,"scale": 73957190.948944,"resolution": 19567.8792409999
}, {"level": 4,"scale": 36978595.474472,"resolution": 9783.93962049996
}, {"level": 5,"scale": 18489297.737236,"resolution": 4891.96981024998
}, {"level": 6,"scale": 9244648.868618,"resolution": 2445.98490512499
}, {"level": 7,"scale": 4622324.434309,"resolution": 1222.99245256249
}, {"level": 8,"scale": 2311162.217155,"resolution": 611.49622628138
}, {"level": 9,"scale": 1155581.108577,"resolution": 305.748113140558
}, {"level": 10,"scale": 577790.554289,"resolution": 152.874056570411
}, {"level": 11,"scale": 288895.277144,"resolution": 76.4370282850732
}, {"level": 12,"scale": 144447.638572,"resolution": 38.2185141425366
}, {"level": 13,"scale": 72223.819286,"resolution": 19.1092570712683
}, {"level": 14,"scale": 36111.909643,"resolution": 9.55462853563415
}, {"level": 15,"scale": 18055.954822,"resolution": 4.77731426794937
}, {"level": 16,"scale": 9027.977411,"resolution": 2.38865713397468
}, {"level": 17,"scale": 4513.988705,"resolution": 1.19432856685505
}, {"level": 18,"scale": 2256.994353,"resolution": 0.597164283559817
}, {"level": 19,"scale": 1128.497176,"resolution": 0.298582141647617
}]
});
this.loaded = true;
this.onLoad(this);
},
getTileUrl: function(level, row, col){
return "http://mt" + (col % 4) + ".google.cn/vt/lyrs=s@112&hl=zh-CN&gl=cn&" + "x=" + col + "&" +
"y=" +
row +
"&" +
"z=" +
level +
"&s=";
}
});
dojo.declare("GoogleMapAnooLayer", esri.layers.TiledMapServiceLayer, { // create WMTSLayer by extending esri.layers.TiledMapServiceLayer
constructor: function(){
this.spatialReference = new esri.SpatialReference({
wkid: 102113
});
this.initialExtent = new esri.geometry.Extent(-20037508.342787, -20037508.342787, 20037508.342787, 20037508.342787, this.spatialReference);
this.fullExtent = new esri.geometry.Extent(-20037508.342787, -20037508.342787, 20037508.342787, 20037508.342787, this.spatialReference);
//
this.tileInfo = new esri.layers.TileInfo({
"dpi": "90.71428571427429",
"format": "image/png",
"compressionQuality": 0,
"spatialReference": {
"wkid": "3857"
},
"rows": 256,
"cols": 256,
"origin": {
"x": -20037508.342787,
"y": 20037508.342787
},
// Scales in DPI 96
"lods": [{"level": 0,"scale": 591657527.591555,"resolution": 156543.033928
}, {"level": 1,"scale": 295828763.795777,"resolution": 78271.5169639999
}, {"level": 2,"scale": 147914381.897889,"resolution": 39135.7584820001
}, {"level": 3,"scale": 73957190.948944,"resolution": 19567.8792409999
}, {"level": 4,"scale": 36978595.474472,"resolution": 9783.93962049996
}, {"level": 5,"scale": 18489297.737236,"resolution": 4891.96981024998
}, {"level": 6,"scale": 9244648.868618,"resolution": 2445.98490512499
}, {"level": 7,"scale": 4622324.434309,"resolution": 1222.99245256249
}, {"level": 8,"scale": 2311162.217155,"resolution": 611.49622628138
}, {"level": 9,"scale": 1155581.108577,"resolution": 305.748113140558
}, {"level": 10,"scale": 577790.554289,"resolution": 152.874056570411
}, {"level": 11,"scale": 288895.277144,"resolution": 76.4370282850732
}, {"level": 12,"scale": 144447.638572,"resolution": 38.2185141425366
}, {"level": 13,"scale": 72223.819286,"resolution": 19.1092570712683
}, {"level": 14,"scale": 36111.909643,"resolution": 9.55462853563415
}, {"level": 15,"scale": 18055.954822,"resolution": 4.77731426794937
}, {"level": 16,"scale": 9027.977411,"resolution": 2.38865713397468
}, {"level": 17,"scale": 4513.988705,"resolution": 1.19432856685505
}, {"level": 18,"scale": 2256.994353,"resolution": 0.597164283559817
}, {"level": 19,"scale": 1128.497176,"resolution": 0.298582141647617
}]
});
this.loaded = true;
this.onLoad(this);
},
getTileUrl: function(level, row, col){
return "http://mt" + (col % 4) + ".google.cn/vt/lyrs=h@177000000&hl=zh-CN&gl=cn&" + "x=" + col + "&" +
"y=" +
row +
"&" +
"z=" +
level +
"&s=";
}
});
}
arcgis jsapi调用初始化的google地图服务：
var googleMapLayer = new GoogleMapLayer(); map.addLayer(googleMapLayer);
通过上面的代码实现就能把google地图服务，添加到自己的项目中。
