在.earth里设置
<map name="bluemarble" type="geocentric" version="2">
<!--Add a reference to the image -->
<image name="bluemarble" driver="gdal">
<url>c:/test.tif</url>
</image>
<!--Tell osgEarth to cache the tiles in a TMS format-->
<options>
<cache type="tms">
<path>c:/osgearth_cache11</path>
<!--Tell osgEarth to cache the tiles to JPG to save disk space-->
<format>jpg</format>
</cache>
</options>
</map>