Why Synchronization Exists
Editor authoring contains hierarchy, Control Rig-facing channels, source bindings, preview data, and other authoring state that runtime should not interpret directly. Synchronization freezes an authoring revision, validates it, resolves inheritance, samples required poses, compiles sparse runtime payloads, and publishes one candidate snapshot only when the full operation succeeds.
When To Synchronize
- After State, Context, Animation Override, Neutral, transform-curve, or composition changes.
- After source binding, transition, stack policy, Aim, or IK changes.
- After relevant compatible external dependencies change.
- Before PIE verification of new authoring, packaging, or release handoff.
Non-Blocking Progress And Cancellation
Synchronization runs in a non-blocking editor notification. You can continue inspecting the editor or choose Cancel; cancellation discards the uncommitted candidate and leaves the previous runtime snapshot unchanged. If authoring changes while synchronization is running, revision validation stops publication and discards the stale candidate. Synchronize again after the edits settle.
Failure Is Non-Destructive
A failed synchronization does not replace the previous valid runtime snapshot. This protects a working runtime result, but it also means PIE can continue to display older synchronized data until the new revision succeeds.
Authoring Versus Runtime Evidence
| Surface | What it can prove |
|---|---|
| Author | The selected local edit is correct. |
| Transient Audition | The current dirty authoring resolves as intended in the editor. |
| Synchronized Audition | The synchronized candidate matches authoring for the same inputs. |
| PIE | The real Animation Blueprint, request, and loaded Set integrate correctly. |
| Packaged build | The saved synchronized asset and runtime modules work in the target build. |
Save Policy
A successful in-memory synchronization is not the same as a saved package. Use the configured save policy deliberately and verify the Set was saved before cooking or distribution.
Validation Strategy
Fix the first owning Error rather than adding compensating keys. Validation covers identity, Skeleton compatibility, source bindings, curves, Aim, IK, runtime schema/freshness, and external dependencies.
See Validation Reference and Troubleshooting for symptom-driven checks.