bl-core-system-groups

name	bl-core-system-groups
description	Use for placing BovineLabs Core systems in scene, simulation, transform, relevancy, pause-aware, presentation, or initialization groups.

Core System Groups

Resolve Core source from Packages/com.bovinelabs.core or its exact package-cache entry. Choose the semantic phase, world scope, and pause policy before adding peer-order attributes.

Group Selection

Need	Group
Run before SceneSystemGroup or before unload removes entities	BeforeSceneSystemGroup
Consume freshly loaded subscene entities	AfterSceneSystemGroup
Broad start-of-simulation setup used by later systems	BeginSimulationSystemGroup
Write LocalTransform before transform propagation	BeforeTransformSystemGroup
Read completed transform results without writing transforms	AfterTransformSystemGroup
Server-only NetCode ghost relevancy	RelevancySystemGroup
Custom simulation root disabled during normal pause	derive from BLSimulationSystemGroup

Do not use BeginSimulationSystemGroup as a generic “run early” bucket or RelevancySystemGroup as a generic network group.

Ordering And Pause

• Select the group first; then use UpdateBefore/UpdateAfter only among peers in that phase.
• Ordering that spans phases usually indicates the wrong group.
• BLSimulationSystemGroup implements IDisableWhilePaused. Mark exceptional child systems with IUpdateWhilePaused rather than inventing a new root.
• Check each built-in group's WorldSystemFilter; re-evaluate placement when the system needs a different world scope.

Boundaries

Use $bl-core-lifecycle for initialize/destroy sequencing and $bl-core-pause for pause-mode behavior. This skill answers where a system belongs.

Failure Triage

• Needs loaded scene data but runs pre-scene: move toward AfterSceneSystemGroup.
• Writes transforms after propagation: move toward BeforeTransformSystemGroup.
• A local ordering issue caused a phase move: restore the phase and order peers instead.
• Feature unexpectedly stops while paused: inspect its root group's pause policy.
• Relevancy logic runs in non-server worlds: use RelevancySystemGroup and verify filters.

Inspect the selected group source under BovineLabs.Core.Extensions/Groups for exact update and world attributes.