In order to properly support the resource sharing paradigm, Occluders are split into Instances and Resources in the VisualServer. Instances are owned by a Scenario, and Resources are global. OccluderShape resources can now correctly be shared by multiple OccluderInstances.
Sphere occluders are now tested for self occlusion. Spheres that are behind another sphere in the current view are superfluous so can be removed, cutting down on the runtime calculations.
AABBs are now maintained for Occluders as well as individual spheres, meaning a bunch of occluder spheres can be frustum rejected as a block.
Add framework for supporting geometrical occluders within rooms, and add support for sphere occluders.
Includes gizmos for editing.
They also work outside the portal system.
