The <combine_layers> element is used to turn on/off the default TexEnvCombine settings in osgEarth if you want to manage them yourself with something like a MultiTextureControl.
You can specify multiple imagery layers by simply specifying multiple <image> blocks in the .earth file. Typically the openstreetmap data does not have a transparent background so it may not display the way you want it to. You can try using the arcgis transportation layer (see the arc_imagery_roads.earth example) which does have a transparent background or look into rendering the osm data yourself.
On Thu, Aug 20, 2009 at 3:03 AM, rahul jain (via Nabble) - No Reply <[hidden email]> wrote:
Is this functionality functional in ver 1.2 ? If yes : How to use it ?
Also If i want to overlay openstreet map data on my terrain or bluemarble layer. Is it possible using this functionality ?