TextSymbol: make size a numericexpression
Merge branch 'master' of github.com:gwaldron/osgearth
Add TextureSplatter
MBTiles: better handling of formats, especially for elevation data
TMS Packager: apply an alpha mask when using an express bounding box
Add accept callback to VP::setFunction
VP: added a ShaderComp::AcceptCallback test to osgearth_shadercomp
VirtualProgram: add a getShaders method
VirtualProgram: Make internal functions protected to prevent shinanigans.