UAnimInstance::GetInstanceStateWeight

function Engine Blueprint Since 4.8

#include "Animation/AnimInstance.h"

Access: public Specifiers: UFUNCTION

Description

Returns the current blend weight of a specific state within a state machine, ranging from 0.0 (not active) to 1.0 (fully active). Used by generated AnimBP code to drive state-aware blend logic and transition conditions.

Caveats & Gotchas

• Both MachineIndex and StateIndex are compiler-assigned constants that change on blueprint recompile. Retrieve them via GetStateMachineIndex() and GetStateMachineInstanceDesc() rather than caching raw integers across editor sessions.
• During a crossfade transition, multiple states may return non-zero weights simultaneously — the weights do not sum to 1.0 across all states until the transition completes.

Signature

UFUNCTION(BlueprintPure, Category="Animation", meta=(BlueprintInternalUseOnly = "true"))
float GetInstanceStateWeight(int32 MachineIndex, int32 StateIndex) const;

Parameters

Name	Type	Description	Default
MachineIndex	int32	Index of the state machine that contains the state.	—
StateIndex	int32	Index of the state within the state machine.	—

Return Type

float

Example

Check if a specific state is fully active C++

int32 MachineIdx = GetStateMachineIndex(FName("LocomotionSM"));
int32 StateIdx   = GetStateMachineInstanceDesc(MachineIdx).GetStateIndex(FName("Run"));
if (GetInstanceStateWeight(MachineIdx, StateIdx) >= 1.0f)
{
	// Fully in Run state
}

Version History

Introduced in: 4.8

Version	Status	Notes
5.6	stable	—

Feedback

Was this helpful?