Turn on a specular feature

We would like to be able to turn on a specular feature on the globe. The feature set seems to be there, but there’s an issue when not rendering with terrain where the globe lighting isn’t properly honored and the magnitude of the light source (i.e. sun vs. moon) is ignored. This issue can be seen by adding this line of code as the last line in Sandcastle's Material demo: scene.globe.enableLighting = true; We would like this to be addressed in a future release of Cesium.

Start with Sandcastle's Material demo and add scene.globe.enableLighting = true as the last line to reproduce the issue. Compare globe lighting without terrain and with different light-source magnitudes, then verify that specular lighting is honored and sun-versus-moon intensity is reflected correctly.

Written by the indexing model from the issue text.