Skip to main content

Crowdy State Metadata Keys

This page lists the metadata you place on a property to control Crowdy State property replication. For the full guide, see Crowdy State.

Come here for the exact key names, their accepted values and defaults, and what a Crowdy State property may hold.

In C++ the keys go on the UPROPERTY(meta=(...)) line. In Blueprint they are set from the variable's Details panel through the Crowdy Replication dropdown, not typed by hand.

UPROPERTY(meta = (CrowdyState,
    CrowdyOnRep = "OnRep_Stance",
    CrowdyOwnerOnly,
    CrowdyManualDirty,
    CrowdyHeartbeat))
uint8 Stance = 0;

UFUNCTION()
void OnRep_Stance();

Keys​

KeySymbolHeader
CrowdyHeartbeatCrowdyStateMetaKeys::HeartbeatCrowdyStateMetaKeys.h
CrowdyManualDirtyCrowdyStateMetaKeys::ManualDirtyCrowdyStateMetaKeys.h
CrowdyOnRepCrowdyStateMetaKeys::OnRepCrowdyStateMetaKeys.h
CrowdyOwnerOnlyCrowdyStateMetaKeys::OwnerOnlyCrowdyStateMetaKeys.h
CrowdyStateCrowdyStateMetaKeys::ReplicateCrowdyStateMetaKeys.h

The manifest carries the symbol and its header; the accepted values, defaults, and behavior below come from the header directly.

CrowdyState takes no value and is required. It marks the property for Crowdy State; the other four keys do nothing without it. Its legal place is any UPROPERTY, never a UFUNCTION or UCLASS.

CrowdyOnRep takes the name of a parameterless notify function and has no default. It runs on the receiver right after the value is written, and only when the value actually changed: GAS-style, no arguments, no previous value. Read the new value off the property itself.

CrowdyOwnerOnly takes no value and defaults to off. It is a delivery scope, not secrecy: the property ships only to the entity's owning client, over the targeted single-actor path, never on the spatial broadcast. This changes who receives the value, not who could intercept it.

CrowdyManualDirty takes no value and defaults to off. It skips the automatic per-tick diff; the value ships only when you call MarkStateDirty. One mark sends exactly the next update, then clears. It is meant for a big or expensive property you do not want diffed every tick.

CrowdyHeartbeat takes no value and defaults to off in C++. It opts a property into the periodic keyframe baseline, so a late-relevant peer gets its current value. On-change replication is unaffected either way: a changed property always ships, marked or not, marked properties are simply re-sent while unchanged too. The Blueprint "Crowdy Replication" dropdown pre-checks Heartbeat the first time a variable enters Replicated mode, as a convenience; the underlying mechanism is the same opt-in metadata either way.

CrowdyOwnerOnly, CrowdyManualDirty, and CrowdyHeartbeat are presence markers. You add the bare key to turn each on; they take no value. The code tests only whether the key is present, so do not write = true -- and = false would still count as on. CrowdyOnRep is the one key that takes a value, the notify function's name.
CrowdyState is deliberately not spelled CrowdyReplicate. That string already belongs to the RPC side, as an alias of the Blueprint marker CrowdyReplicates. Reusing it here would make one key mean two different systems and break RPC-versus-state discovery. If you came from the RPC metadata keys page expecting the two families to mirror each other by name, they do not, on purpose. See RPC metadata keys.

What can be marked​

Crowdy State covers plain values and plain structs: numbers, bools, enums, FName, FString, and USTRUCTs built from those. Object references, containers (TArray, TSet, TMap, including buried inside a struct), and static arrays are rejected at discovery and simply do not replicate. See Unsupported types for the full list and the reasons.

A struct type that carries a native net serializer (FVector_NetQuantize, FRotator, and the rest of the _NetQuantize family) quantizes on the wire automatically, with no key to set. See type-driven quantization.

The Blueprint "Crowdy Replication" dropdown offers None and Replicated; Replicated writes these keys for you. A CrowdyModel or CrowdyContainer key left on a property from the removed Game Model API does nothing; see Move from Game Models.

HasMetaData-backed discovery helpers, including the one behind this header, answer false in a cooked build, because cooked builds strip metadata. A runtime check routes through the baked registry instead, never through live metadata.

Gotchas​

  • All five keys go on a UPROPERTY; none apply to a UFUNCTION or UCLASS.
  • CrowdyHeartbeat only changes how often an unchanged value is re-sent. A changed value always ships, heartbeat or not.
  • A property is discovered live only in the editor. A packaged build reads the baked rep table, not the metadata on the header.