AAMjManager

Thin coordinator actor for the MuJoCo simulation within Unreal Engine.

Owns subsystem components and delegates to them: - UMjPhysicsEngine: simulation lifecycle, model/data, options, async loop - UMjDebugVisualizer: debug drawing, collision wireframes - UMjNetworkManager: ZMQ components, camera streaming - UMjInputHandler: keyboard hotkeys External code accesses subsystem state via Manager->PhysicsEngine->X, etc.

Attribute	Value
Kind	Class
UE Macro	UCLASS
Inherits	AActor

Properties Functions

Properties

Public Properties

Property	Type	Description
PhysicsEngine	UMjPhysicsEngine*
DebugVisualizer	UMjDebugVisualizer*
NetworkManager	UMjNetworkManager*
InputHandler	UMjInputHandler*
Perturbation	UMjPerturbation*	Mouse-driven body perturbation (simulate-style Ctrl+LMB/RMB drag).
Instance	static AAMjManager*	Set in BeginPlay, cleared in EndPlay. Use GetManager() from Blueprints.
bAutoCreateSimulateWidget	bool
StepMode	EStepMode	Step mode for the simulation.
Seed	int32	Deterministic seed written to m->opt.seed before compile.
BridgeServer	TObjectPtr<UURLabBridgeServer>	Owns the FURLabRpcDispatcher + transports. Created in BeginPlay, destroyed in EndPlay.
ManagerOwnedPublishTransports	TArrayUURLabPublishTransport\>>	Manager-owned UObject publish transports
ManagerOwnedSubscribeTransports	TArrayUURLabSubscribeTransport\>>	Manager-owned UObject subscribe transports
m_MujocoComponents	TArray<UMjQuickConvertComponent*>
m_articulations	TArray<AMjArticulation*>
m_heightfieldActors	TArray<AMjHeightfieldActor*>

PhysicsEngine

• Type: UMjPhysicsEngine*
• Editor: 👁 VisibleAnywhere
• Blueprint: 🟢 ReadOnly
• Category: MuJoCo

DebugVisualizer

• Type: UMjDebugVisualizer*
• Editor: 👁 VisibleAnywhere
• Blueprint: 🟢 ReadOnly
• Category: MuJoCo

NetworkManager

• Type: UMjNetworkManager*
• Editor: 👁 VisibleAnywhere
• Blueprint: 🟢 ReadOnly
• Category: MuJoCo

InputHandler

• Type: UMjInputHandler*
• Editor: 👁 VisibleAnywhere
• Blueprint: 🟢 ReadOnly
• Category: MuJoCo

Perturbation

Mouse-driven body perturbation (simulate-style Ctrl+LMB/RMB drag).

• Type: UMjPerturbation*
• Editor: 👁 VisibleAnywhere
• Blueprint: 🟢 ReadOnly
• Category: MuJoCo

Instance

Set in BeginPlay, cleared in EndPlay. Use GetManager() from Blueprints.

• Type: static AAMjManager*

bAutoCreateSimulateWidget

• Type: bool
• Editor: ✏️ EditAnywhere
• Blueprint: 🔵 ReadWrite
• Category: MuJoCo|UI

StepMode

Step mode for the simulation.

• Type: EStepMode
• Editor: ✏️ EditAnywhere
• Blueprint: 🔵 ReadWrite
• Category: MuJoCo|Remote Stepping

Seed

Deterministic seed written to m->opt.seed before compile.

• Type: int32
• Editor: ✏️ EditAnywhere
• Blueprint: 🔵 ReadWrite
• Category: MuJoCo|Remote Stepping

BridgeServer

Owns the FURLabRpcDispatcher + transports. Created in BeginPlay, destroyed in EndPlay.

• Type: TObjectPtr<UURLabBridgeServer>

ManagerOwnedPublishTransports

Manager-owned UObject publish transports

• Type: TArrayUURLabPublishTransport\>>

ManagerOwnedSubscribeTransports

Manager-owned UObject subscribe transports

• Type: TArrayUURLabSubscribeTransport\>>

m_MujocoComponents

• Type: TArray<UMjQuickConvertComponent*>
• Editor: ✏️ EditAnywhere
• Blueprint: 🟢 ReadOnly
• Category: Mujoco Physics|Objects

m_articulations

• Type: TArray<AMjArticulation*>
• Editor: ✏️ EditAnywhere
• Blueprint: 🟢 ReadOnly
• Category: Mujoco Physics|Objects

m_heightfieldActors

• Type: TArray<AMjHeightfieldActor*>
• Editor: ✏️ EditAnywhere
• Blueprint: 🟢 ReadOnly
• Category: Mujoco Physics|Objects

Protected Properties

Property	Type	Description
m_ArticulationMap	TMapAMjArticulation\*>	O(1) articulation lookup built in PostCompile. Key = actor name.
SnapshotPublishers	TArray<FRegisteredSnapshotPublisher>	Snapshot publishers registered by their owning components. Read on

m_ArticulationMap

O(1) articulation lookup built in PostCompile. Key = actor name.

• Type: TMapAMjArticulation\*>

SnapshotPublishers

Snapshot publishers registered by their owning components. Read on

• Type: TArray

Functions

Public Functions

General

Function	Returns	Description
GetEntities()	const TArray<FMjEntityRecord>&	Non-articulation entity table built in PostCompile; empty until then.
BuildEntityCache()	void	Refresh the entity cache; called from PostCompile.
RegisterSnapshotPublisher()	void	Snapshot publishers share one per-step state_full payload — each

GetEntities

Non-articulation entity table built in PostCompile; empty until then.

• Signature: GetEntities()
• Returns: const TArray<FMjEntityRecord>&

BuildEntityCache

Refresh the entity cache; called from PostCompile.

• Signature: BuildEntityCache()

RegisterSnapshotPublisher

Snapshot publishers share one per-step state_full payload — each

• Signature: RegisterSnapshotPublisher(IMjSnapshotPublisher* Publisher, class UObject* OwnerObj)

MuJoCo|Control

Function	Returns	Description
StepSync()	void	Pauses the async loop, steps N times synchronously, then restores pause state.

StepSync

Pauses the async loop, steps N times synchronously, then restores pause state.

• Signature: StepSync(int32 NumSteps)
• Blueprint: 🔵 Callable

MuJoCo|Snapshot

Function	Returns	Description
RestoreSnapshot()	void	Restore is scheduled for the next physics step (not applied immediately).

RestoreSnapshot

Restore is scheduled for the next physics step (not applied immediately).

• Signature: RestoreSnapshot(UMjSimulationState* Snapshot)
• Blueprint: 🔵 Callable

MuJoCo|UI

Function	Returns	Description
ToggleSimulateWidget()	void	Bound to Tab key.

ToggleSimulateWidget

Bound to Tab key.

• Signature: ToggleSimulateWidget()
• Blueprint: 🔵 Callable