First cut of a general quadtree primitive.
Much better handling of async geometry.
Closer to working ExtentTileProvider in 2D/CV.
Do not release terrain mesh data after creating vertex array.
Add ray-triangle intersection test.
Add ray-triangle intersection tests.
Add ray-sphere intersection test.
Pick rendered tiles bounding spheres.
Pick terrain mesh.
Merge branch 'master' into pick-terrain
Updates after merge.
Merge branch 'master' into pick-terrain
Pan terrain in 3D.
Merge branch 'master' into pick-terrain
Pick terrain when tilting in 3D.
Add picking terrain and use it when tilting in Columbus view.
Pick terrain in Columbus view when panning.
Some clean up.
Merge branch 'master' into pick-terrain
Some more clean up.