osgearth加载影像数据TMS、Tif、XYZ

加载TMS文件

		TMSOptions imagery;
		imagery.url() = "http://readymap.org/readymap/tiles/1.0.0/22/";
		m_pMap->addLayer(new ImageLayer("ReadyMap Imagery", imagery));

加载TIF、IMG等格式文件

	         GDALOptions gdal;
			 gdal.url() = pDataSource.strFile;
			 osg::ref_ptr<ImageLayer> pImageLayer = new ImageLayer(pDataSource.strName, gdal);
			 m_pMap->addLayer(pImageLayer);

加载XYZ格式文件

	osgEarth::Drivers::XYZOptions tileOptions;
	tileOptions.url() = "http://[abc].tile.openstreetmap.org/{z}/{x}/{y}.png";
	tileOptions.profile()->namedProfile()=("spherical-mercator");
	osgEarth::ImageLayerOptions options = ImageLayerOptions("debug", tileOptions);
	osg::ref_ptr<osgEarth::ImageLayer> layer = new ImageLayer(options);
	mapNode->getMap()->addImageLayer(layer);

加载MB格式文件

	 MBTilesTileSourceOptions pMBTiles;
			 pMBTiles.filename() = pDataSo