arenaRing

A flat annulus in the XZ plane, inner radius 11.85, outer radius 12.15, 128 segments, normals up. It is the painted line on the lab floor marking the 12 metre arena the FruitFly component's arenaRadius keeps the fly inside.

Place it on an entity a little above the floor (ArenaRing sits at y = 0.02) with a Model and a tint; it casts no shadow.

The radius is baked into the geometry rather than taken from the entity's scale, so the ring cannot drift out of agreement with arenaRadius by somebody resizing the entity. If arenaRadius ever moves, re-author the mesh.