gwaldron/osgearth — pull request #392 by aroth-fastprotect (2013-10-29 14:45:19+00:00)
Title: use tileSource->hasData()

to check if tileSource has data for the requested key. Add tileSource->hasDataForFallback() for cases when fallback data is requested

I added the method hasDataForFallback() to the TileSource. This might now be the best solution, but i hope that i didn't missed any use-case.