Architecture

Review draft. This source page has not completed website editorial and release-specific verification.

Diagnostic Director keeps durable events and temporary observations separate. Log Diagnostic writes sequential events to Unreal logging. Diagnostic Probe writes only the latest formatted state to transient runtime storage and may optionally write a separate Unreal log event.

Probe runtime storage is transient, non-replicated, and not SaveGame state. It holds a weak world reference and session-local update count/time. At PIE shutdown the Editor marks the latest snapshot complete and drops the world reference. The next session resets the state on its first hit.

The DiagnosticDirector Runtime module owns the Blueprint/C++ recording APIs, transient latest-state model, and Probe log category. The DiagnosticDirectorNodes UncookedOnly module owns the wildcard custom K2 node and compile expansion into runtime API calls. The DiagnosticDirectorEditor Editor module owns the asynchronous cached Blueprint catalog, exact-node navigation, Slate Inspector, and Director Suite registration. The Editor discovers the node by reflected class identity, avoiding a binary dependency on the UncookedOnly module. Compiled game Blueprints call only the Runtime module; game execution does not require the Nodes or Editor modules.

The Inspector is strictly read-only. Watching and filtering affect presentation only. Remaining Blueprint nodes are reported for release cleanup; the plugin does not alter Blueprints or impose a cook/package blocker.