Flat 2D polygon shape for use with occlusion culling in [OccluderInstance3D]. [PolygonOccluder3D] stores a polygon shape that can be used by the engine's occlusion culling system. When an [OccluderInstance3D] with a [PolygonOccluder3D] is selected in the editor, an editor will appear at the top of the 3D viewport so you can add/remove points. All points must be placed on the same 2D plane, which means it is not possible to create arbitrary 3D shapes with a single [PolygonOccluder3D]. To use arbitrary 3D shapes as occluders, use [ArrayOccluder3D] or [OccluderInstance3D]'s baking feature instead. See [OccluderInstance3D]'s documentation for instructions on setting up occlusion culling. The polygon to use for occlusion culling. The polygon can be convex or concave, but it should have as few points as possible to maximize performance. The polygon must [i]not[/i] have intersecting lines. Otherwise, triangulation will fail (with an error message printed).