Create 3d pie and hemisphere entities.

How to create 3d pie and hemisphere as entities in cesium.

We have a PR opened by an external contributor, #5995, for partial ellipsoids (hemispheres), but unfortunately it was lacking unit tests so it can’t be merged yet. If you have the bandwidth, you could help get it across the finish line!

For 3D pies, we don’t have a way to “slice” out part of a cylinder via the API, but you could create an extruded polygon.