Add scene side discrete level of detail.
New node `LOD` for UI, and `LODManager` within `World` for automatically updating child visibilities based on distance from cameras.
Existing shadow caster culling using the BVH takes no account of the camera. This PR adds the highly encapsulated class VisualServerLightCuller which can cut down the casters in the shadow volume to only those which can cast shadows on the camera frustum.
This is used to:
* More accurately defer dirty updates to shadows when the shadow volume does not intersect the camera frustum.
* Tighter cull shadow casters to the view frustum.
Lights dirty state is now automatically managed:
* Continuous (tighter caster culling)
* Static (all casters are rendered)
- lawnjelly
8ca631a466
Move VisualServer interpolation data out of Scenario and into VisualServerScene, so the interpolation data and enabled status is now common to all Scenarios.
Fix physics interpolation in multithreaded mode by ensuring tick and pre-draw are called.
- lawnjelly
d2b1d29634
Later logic using the `pairable_mask` would catch cases preventing pairing callbacks between geometry. However the collision checks were still taking place, wasting performance.
Here we utilize the `tree_mask` feature of BVH to totally eliminate unnecessary collision checks between geometry.
- lawnjelly
18d7d36b63
