OptionalcellOptionalphasesPhases to register rebuild systems in (default: ['fixedUpdate', 'postUpdate']).
When both phases are registered, the postUpdate rebuild is
automatically skipped on cycles where:
fixedUpdate rebuild already ran this cycle, ANDIn flat-hierarchy scenes transform3d-propagation copies
localTransform3D → worldTransform3D unchanged, so the postUpdate
grid would duplicate the fixedUpdate one. The skip is automatic
and re-engages once any parent relationship is set, or whenever
fixedUpdate doesn't run that cycle (sub-fixed-DT frames).
Edge case: if you write to worldTransform3D directly between
phases without using transform3d-propagation or entity hierarchy,
the auto-skip will leave your writes unindexed. Set
phases: ['postUpdate'] explicitly to bypass the auto-skip.
OptionalpriorityPriority for rebuild systems (default: 2000, before collision)
OptionalsystemSystem group name (default: 'spatialIndex3D')
Cell size for the spatial hash grid (default: 64)