1. Epic GamesDeveloper
  3. NetworkPrediction

NetworkPrediction

Unreal Engine C++ API Reference > Plugins

Filters

Classes

  Type Name Description
Public class UClass ANetworkPredictionReplicatedManager    
Public struct AuthorityOnly Will only play on the authority path and not replicate to anyone else.  
Public struct FConditionalAutoConsoleRegister This is required because these cvars live in header files that will be included across different compilation units Just using standard FAutoConsoleVariableRef will cause multiple registrations of the same variable  
Public struct FConditionalSimulationPtr    
Public struct FCueDispatcherTraitsBase Traits for TNetSimCueDispatcher.  
Public struct FFixedTickState (Global) Tick state for fixed tick services  
Public struct FGenericKinematicActorDef Generic def for kinematic (non physics) actor that doesn't have a backing simulation.  
Public struct FGenericKinematicActorSyncState    
Public struct FGenericPhysicsModelDef Generic model def for physics actors with no backing simulation  
Public class FGlobalCueTypeTable GlobalCueTypeTable: Cue types register with this to get a Type ID assigned (TCue::ID).  
Public struct FNetSerializeParams The parameters for NetSerialize that are passed around the system. Everything should use this, expecting to have to add more.  
Public struct FNetSimCueCallbacks Callbacks  
Public struct FNetSimCueDispatcher Non-templated, "networking model independent" base: this is what the pure simulation code gets to invoke cues.  
Public struct FNetSimCueSystemParamemters System parameters for NetSimCue events  
Public struct FNetSimCueWrapperBase Wrapper: wraps the actual user NetSimCue.  
Public struct FNetSimTimeStep TimeStep info that is passed into SimulationTick.  
Public struct UStruct meta FNetworkPredictionDevHUD    
Public struct UStruct meta FNetworkPredictionDevHUDItem    
Public struct FNetworkPredictionDriver This is the actual template to specialize when wanting to override functions.  
Public struct FNetworkPredictionDriverBase    
Public struct FNetworkPredictionID Unique server assigned ID for a network sim instance.  
Public struct FNetworkPredictionInstanceArchetype How a registered instance should behave globally.  
Public struct FNetworkPredictionInstanceConfig The config should tell us what services we should be subscribed to.  
Public struct FNetworkPredictionModelDef    
Public struct FNetworkPredictionModelDefCapabilities What a ModelDef of capable of.  
Public class FNetworkPredictionModelDefRegistry Basic ModelDef type registry.  
Public struct FNetworkPredictionPhysicsState Actual physics state.  
Public struct UStruct FNetworkPredictionProxy    
Public struct FNetworkPredictionSerialization    
Public struct UStruct meta FNetworkPredictionSettings    
Public struct FNetworkPredictionStateView Generic view into a managed instance's state.  
Public class FNetworkPredictionTrace    
Public struct UStruct FReplicationProxy Redirects NetSerialize to a dynamically set NetSerializeFunc.  
Public struct FReplicationProxySet Collection of each replication proxy.  
Public struct FSavedCue SavedCue: a recorded Invocation of a NetSimCue  
Public struct FScopedBandwidthLimitBypass Helper struct to bypass the bandwidth limit imposed by the engine's NetDriver (QueuedBits, NetSpeed, etc).  
Public struct UStruct FServerReplicationRPCParameter FServerRPCProxyParameter Used for the client->Server RPC.  
Public struct FServiceTimeStep Data that is needed to tick the internal ticking services but is not passed to the user code.  
Public struct UStruct FSharedPackageMap    
Public struct UStruct FSharedPackageMapItem This is a replicated "manager" for network prediction.  
Public struct FVariableTickState Variable tick state tracking for independent tick services.  
Public class INetworkPredictionModule    
Public struct NonReplicatedResimulated Non replicated but if a resimulate happens, the cue is undone and replayed.  
Public struct ReplicatedNonPredicted Only invoked on authority and will replicate to everyone else.  
Public struct ReplicatedXOrPredicted Replicated to interpolating proxies, predicted by autonomous/simulated proxy Best for events you want everyone to see but don't need to get perfect in the predicting cases: doesn't need to rollback and cheap on cpu (no NetIdentical tests on predicted path)  
Public struct Strong Invoked and replicated to all.  
Public class TCommonReplicator_AP Server -> AP Client  
Public class TCommonReplicator_SP Server -> SP Client Like the AP case, the core payload is the same between fixed and independent: Input/Sync/Aux/Physics/Cues  
Public struct TConditionalState    
Public struct TCueDispatcherTraits    
Public class TCueDispatchTable Per-Receiver dispatch table. This is how we go from a serialized ID to a function call  
Public class TFixedTickReplicator_AP    
Public class TFixedTickReplicator_Server AP Client -> Server replication  
Public class TFixedTickReplicator_SP    
Public struct THasNetIdenticalHelper Helper to compile time check if NetIdentical exists (since argument is template type, must be wrapped in helper struct)  
Public struct THasNetSimCueTraits Helper to see if T has a Traits type or not.  
Public class TIndependentTickReplicator_AP    
Public class TIndependentTickReplicator_Server    
Public class TIndependentTickReplicator_SP    
Public struct TNetCueNetIdenticalHelper Helper to call NetIdentical if type defines it.  
Public struct TNetCueNetSerializeHelper Helper to call NetSerialize if type defines it.  
Public struct TNetSimCueDispatcher Templated cue dispatcher that can be specialized per networking model definition. This is what the system actually uses internally, but is not exposed to user code.  
Public struct TNetSimCueHandlerAutoRegisterHelper Register a handler's cue types via a static "RegisterNetSimCueTypes" on the handler itself  
Public struct TNetSimCueSetHandlerAutoRegisterHelper Register a handler's cue types via an intermediate "set" class with a static "RegisterNetSimCueTypes" function  
Public struct TNetSimCueTraits Actual trait struct that we use to look up traits.  
Public struct TNetSimCueTraitsExplicit Explicit trait settings. This can be used to explicitly set your traits without using a preset.  
Public struct TNetSimCueTypeAutoRegisterHelper Register a cue type with the global table.  
Public struct TNetSimCueTypeRequirements Type requirements: helper to determine if NetSerialize/NetIdentical functions need to be defined for user types based on the above traits.  
Public struct TNetSimCueWrapper    
Public struct TNetSimLazyWriter Reference version of LazyWriter. This is what gets passed through chains of ::SimulationTick calls. This is to avoid copying the TFunction in TNetSimLazyWriterFunc around.  
Public struct TNetSimLazyWriterFunc Helper struct to encapsulate optional, delayed writing of new element to TNetworkSimAuxBuffer buffer.  
Public struct TNetSimOutput Output state: the output SyncState (always created) and TNetSimLazyWriter for the AuxState (created on demand since every tick does not generate a new aux frame)  
Public struct TNetworkedSimulationState    
Public struct TNetworkPredictionBuffer Circular buffer for storing continuous frame data.  
Public struct TNetworkPredictionModelDefRegisterHelper    
Public struct TNetworkPredictionModelInfo    
Public struct TNetworkPredictionState Tuple of state types.  
Public struct TNetworkPredictionStateTypes State type defines.  
Public struct TNetworkSimAuxBuffer Sparse buffer: each element has explicit Frame value.  
Public struct TSelectNetSimCueTraits Selects explicit traits set by T.  
Public struct TSyncAuxPair Just the Sync/Aux pair.  
Public struct TToVoid SFINAE helper.  
Public class UClass Abstract UNetworkPredictionComponent UNetworkPredictionComponent This is the base component for running a TNetworkedSimulationModel through an actor component.  
Public class UClass BlueprintType Meta UNetworkPredictionPhysicsComponent UNetworkPredictionPhysicsComponent  
Public class UClass Meta Config defaultconfig UNetworkPredictionSettingsObject    
Public class UClass UNetworkPredictionWorldManager    
Public struct Weak Non replicated cue that only plays during "latest" simulate.  
Public struct WeakClientsOnly Same as above but will play on all clients, just not the authority.  
Public struct WeakOwningClientOnly Same as above but will only play on the owning, autonomous proxy client (not on authority, not on simulated clients) Useful if the Cue is needed for only the controlling player, maybe like a HUD/UI notification pop  

Typedefs

Name Description
Default Default Traits: if you do not explicitly set Traits on your class, this is what it defaults to.
FModelDefId  
FNetSimCueTypeId  
TNetSimInput Input state is just a collection of references to the simulation state types.

Enums

  Type Name Description
Public enum ENetSimCueInvoker High level "who can invoke this". Does not take resimulate into account yet. All combinations of this enum are valid (though Authority | SimExtrapolate is a bit weird maybe)  
Public enum ENetSimCueReplicationTarget Who a NetSimCue should replicate/be accepted by.  
Public enum UEnum ENetworkLOD Must be kept in sync with ENP_NetworkLOD.  
Public enum ENetworkPredictionLocalInputPolicy    
Public enum ENetworkPredictionSortPriority Arbitrary sort values used by system default definitions.  
Public enum UEnum ENetworkPredictionStateRead    
Public enum ENetworkPredictionStateType Copyright Epic Games, Inc. All Rights Reserved.  
Public enum UEnum ENetworkPredictionTickingPolicy Must be kept in sync with ENP_TickingPolicy.  
Public enum EReplicationProxyTarget Target of replication.  
Public enum ESimulationTickContext When we run a SimulationTick, it will be done under one of these contexts. This isn't NetSimCue specific and probably makes sense to move to the NetSimModel types.  

Functions

  Type Name Description
Public function IConsoleVariable *

FindConsoleVarHelper ( const TCHAR* VarName
)

 "Shipping const" cvars: cvars that should compile out to const functions in shipping/test builds This got a little tricky due to templated usage across different modules.
Public function  

GENERATE_MEMBER_FUNCTION_CHECK ( NetSerialize,
void,
FArchive&
)

 Helper to compile time check if NetSerialize exists.
Public function Static constexpr ENetworkLOD  
Public function Static constexpr ESimulationTickContext

GetSimTickMask ( const ENetSimCueInvoker Invoker,
const bool bAllowResimulate
)

 Turns "Who can invoke this" + "Does this play during resimulate" into the final ESimulationTickContext mask we use at runtime. This is done so users can't make invalid configurations (like "Authority | Resimulate")
Public function const TCHAR *  
Public function FString  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

NetworkPredictionCVars::ForceSendDefaultInputCommandsAuto ( TEXT("np.ForceSendDefaultInputCommands"),
(int32) 0,
TEXT("While enabled on a client, it will send default input cmds to the server, rather than the loca...
)

  
Public function void  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

NetworkPredictionPhysicsCvars::DebugPositionCorrectionsAuto ( TEXT("np.Physics.DebugPositionCorrections"),
(int32) 0,
TEXT("Prints position history when correcting physics X")
)

  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

NetworkPredictionPhysicsCvars::FullPrecisionAuto ( TEXT("np.Physics.FullPrecision"),
(int32) 1,
TEXT("Replicatre physics state with full precision. Not to be toggled during gameplay.")
)

  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function float  
Public function Static FConditionalAutoConsoleRegister

NetworkPredictionPhysicsCvars::ToleranceRAuto ( TEXT("np.Physics.Tolerance.R"),
(float) 0. 1,
TEXT("Normalized error tolerance between rotation (0..1)")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

NetworkPredictionPhysicsCvars::ToleranceVAuto ( TEXT("np.Physics.Tolerance.V"),
(float) 1. 0,
TEXT("Absolute error tolerance for velocity ")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

NetworkPredictionPhysicsCvars::ToleranceWAuto ( TEXT("np.Physics.Tolerance.W"),
(float) 1. 0,
TEXT("Absolute error tolerance for rotational velocity ")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

NetworkPredictionPhysicsCvars::ToleranceXAuto ( TEXT("np.Physics.Tolerance.X"),
(float) 1. 0,
TEXT("Absolute tolerance for position")
)

  
Public function void

NpClearBitArray ( BitArrayType& BitArray
)

 Set bit array contents to false.
Public function void

NpResizeAndSetBit ( BitArrayType& BitArray,
int32 Index,
bool Value
)

 Sets index to value, resizing bit array if necessary and setting new bits to false.
Public function void

NpResizeBitArray ( BitArrayType& BitArray,
int32 NewNum
)

 Resize BitArray to NewNum, setting default value of new bits to false.
Public function void

NpResizeForIndex ( ArrayType& Array,
int32 Index
)

  
Public function constexpr bool  
Public function constexpr bool  
Public function constexpr bool  
Public function constexpr bool  
Public function constexpr bool  
Public function constexpr ENetworkPredictionTickingPolicy  
Public function constexpr ENetworkLOD  
Public function constexpr ESimulationTickContext  
Public function constexpr ENetSimCueInvoker  
Public function constexpr ENetSimCueReplicationTarget  
Public function ENetSimCueInvoker &  
Public function ENetSimCueReplicationTarget &  
Public function ENetworkLOD &  
Public function ENetworkPredictionTickingPolicy &  
Public function ESimulationTickContext &  
Public function constexpr ENetSimCueReplicationTarget  
Public function constexpr ENetSimCueInvoker  
Public function constexpr ESimulationTickContext  
Public function constexpr ENetworkLOD  
Public function constexpr ENetworkPredictionTickingPolicy  
Public function ENetSimCueReplicationTarget &  
Public function ENetworkLOD &  
Public function ENetworkPredictionTickingPolicy &  
Public function ENetSimCueInvoker &  
Public function ESimulationTickContext &  
Public function constexpr ENetSimCueReplicationTarget  
Public function constexpr ENetworkLOD  
Public function constexpr ESimulationTickContext  
Public function constexpr ENetSimCueInvoker  
Public function constexpr ENetworkPredictionTickingPolicy  
Public function ENetworkPredictionTickingPolicy &  
Public function ENetworkLOD &  
Public function ENetSimCueInvoker &  
Public function ENetSimCueReplicationTarget &  
Public function ESimulationTickContext &  
Public function constexpr ENetworkPredictionTickingPolicy  
Public function constexpr ENetworkLOD  
Public function constexpr ESimulationTickContext  
Public function constexpr ENetSimCueReplicationTarget  
Public function constexpr ENetSimCueInvoker  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::bFutureInputsAuto ( TEXT("np2.FutureInputs"),
(int32) 0,
TEXT("Enable FutureInputs feature")
)

  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::bInputDecayAuto ( TEXT("np2.InputDecay"),
(int32) 0,
TEXT("Enable Input Decay Feature")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::DampYawVelocityKAuto ( TEXT("np2.Mock.DampYawVelocityK"),
(float) 2. f,
TEXT("Coefficient for damping angular velocity in yaw direction only. This is only enabled when auto...
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::DragKAuto ( TEXT("np2.Mock.DragK"),
(float) 1. 12f,
TEXT("Drag Coefficient (higher=more drag)")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::InputDecayRateAuto ( TEXT("np2.InputDecayRate"),
(float) 0. 99f,
TEXT("Rate of input decay")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::JumpForceAuto ( TEXT("np2.Mock.JumpForce"),
(float) 70,
TEXT("Per-Frame force to apply while jumping.")
)

  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::JumpFrameDurationAuto ( TEXT("np2.Mock.JumpFrameDuration"),
(int32) 4,
TEXT("How many frames to apply jump force for")
)

  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::JumpFudgeFramesAuto ( TEXT("np2.Mock.JumpFudgeFrames"),
(int32) 10,
TEXT("How many frames after being in air do we still allow a jump to begin")
)

  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::JumpHackAuto ( TEXT("np2.Mock.JumpHack"),
(int32) 0,
TEXT("Make jump not rely on trace which currently causes non determinism")
)

  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::JumpMisPredictAuto ( TEXT("np2.Mock.JumpMisPredict"),
(int32) 0,
TEXT("Make jump do random impulse which will cause a misprediction")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::MaxAngularVelocityAuto ( TEXT("np2.Mock.MaxAngularVelocity"),
(float) 30. f,
TEXT("Limits how fast character can possibly rotate.")
)

  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::MockDebugAuto ( TEXT("np2.Mock.MockDebug"),
(int32) 0,
TEXT("Enabled spammy log debugging of mock physics object state")
)

  
Public function int32  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::MockImpulseAuto ( TEXT("np2.Mock.BallImpulse"),
(int32) 1,
TEXT("Make jump not rely on trace which currently causes non determinism")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::MockImpulseXAuto ( TEXT("np2.Mock.BallImpulse.X"),
(float) 500. 0f,
TEXT("X magnitude")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::MockImpulseZAuto ( TEXT("np2.Mock.BallImpulse.Z"),
(float) 300. 0f,
TEXT("Z magnitude")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::MovementKAuto ( TEXT("np2.Mock.MovementK"),
(float) 1. 25,
TEXT("Movement Coefficient (higher=faster movement)")
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::RotationKAuto ( TEXT("np2.Mock.RotationK"),
(float) 1. 25,
TEXT("Rotation Coefficient (higher=faster movement)")
)

  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::TurnDampKAuto ( TEXT("np2.Mock.TurnDampK"),
(float) 100. f,
TEXT("Coefficient for damping portion of turn. Higher=more damping but too higher will lead to insta...
)

  
Public function float  
Public function Static FConditionalAutoConsoleRegister

UE_NETWORK_PHYSICS::TurnKAuto ( TEXT("np2.Mock.TurnK"),
(float) 100000000. f,
TEXT("Coefficient for automatic turning (higher=quicker turning)")
)

  

Variables

  Type Name Description
Public variable const int32 FrameStorageGrowth  
Public variable const int32 InlineSimObjInputs  
Public variable const int32 InputCmdBufferSize  
Public variable const int32 MaxAsyncModelDefs  
Public variable const int32 NumFramesStorage  

Ask questions and help your peers Developer Forums

Write your own tutorials or read those from others Learning Library

On this page