Skill: Setup Actor Replication

Description

Configure an actor class for network replication in multiplayer UE games.

Arguments

• {{arg}}: Actor class to configure replication for

Steps

Option A: Blueprint Native Tool Routes (In-Editor Asset Configuration)

1. Configure Actor Network Replication (configure_actor_replication): Use configure_actor_replication to set network replication defaults on a Blueprint actor CDO:

   {
     "TargetAsset": "/Game/Blueprints/BP_NetworkPawn",
     "bReplicates": true,
     "bReplicateMovement": true,
     "NetDormancy": "DORM_Never",
     "NetUpdateFrequency": 100.0,
     "NetPriority": 1.0
   }
   

2. Configure Variable Replication & RepNotify (set_variable_replication):

   • Standard Variable Replication:

     {
       "TargetAsset": "/Game/Blueprints/BP_NetworkPawn",
       "VariableName": "Health",
       "ReplicationType": "Replicated",
       "ReplicationCondition": "COND_None"
     }
     

   • Replication with RepNotify Callback: Setting ReplicationType to "RepNotify" and specifying RepNotifyFunc will automatically generate the OnRep_Shield callback graph:

     {
       "TargetAsset": "/Game/Blueprints/BP_NetworkPawn",
       "VariableName": "Shield",
       "ReplicationType": "RepNotify",
       "RepNotifyFunc": "OnRep_Shield",
       "ReplicationCondition": "COND_None"
     }
     

   • Replication with Lifetime Condition (Owner Only / Skip Owner):

     {
       "TargetAsset": "/Game/Blueprints/BP_NetworkPawn",
       "VariableName": "SecretData",
       "ReplicationType": "Replicated",
       "ReplicationCondition": "COND_OwnerOnly"
     }
     

Option B: C++ Code Patterns (Base Class Implementation)

1. Constructor: Enable replication

   bReplicates = true;
   SetReplicateMovement(true);
   

2. Add GetLifetimeReplicatedProps:

   void {{arg}}::GetLifetimeReplicatedProps(TArray<FLifetimeProperty>& OutLifetimeProps) const
   {
       Super::GetLifetimeReplicatedProps(OutLifetimeProps);
       DOREPLIFETIME({{arg}}, Health);
       DOREPLIFETIME_CONDITION({{arg}}, bIsVisible, COND_OwnerOnly);
   }
   

3. Mark properties for replication:

   Standard Replication (No callback):

   UPROPERTY(Replicated)
   float Health;
   

   Replication with RepNotify Callback (Client side effect):

   UPROPERTY(ReplicatedUsing=OnRep_Shield)
   float Shield;
   
   UFUNCTION()
   void OnRep_Shield(float OldShield);
   

4. Server RPCs for player actions:

   UFUNCTION(Server, Reliable)
   void ServerDoAction();
   

5. Required include: #include "Net/UnrealNetwork.h"

Python API Tip (UE 5.8)

• To set replication on a Blueprint CDO via Unreal Python: cdo = bp.get_editor_property('generated_class').get_default_object(), call cdo.set_replicates(True), and compile with unreal.BlueprintEditorLibrary.compile_blueprint(bp).