Skip to main content

FAnimNode_KawaiiPhysics

API reference for the main KawaiiPhysics AnimGraph node.

View Source

Class Definition​

USTRUCT(BlueprintType)
struct KAWAIIPHYSICS_API FAnimNode_KawaiiPhysics : public FAnimNode_SkeletalControlBase

Bone Settings​

PropertyTypeDefaultDescription
RootBoneFBoneReference-Root bone for control target
ExcludeBonesTArray<FBoneReference>-Bones to exclude from control
AdditionalRootBonesTArray<FKawaiiPhysicsRootBoneSetting>-Additional root bone settings
DummyBoneLengthfloat0.0Dummy bone length
BoneForwardAxisEBoneForwardAxisX_PositiveBone forward axis

Physics Settings​

PropertyTypeDefaultDescription
PhysicsSettingsFKawaiiPhysicsSettings-Basic physics control settings
SimulationSpaceEKawaiiPhysicsSimulationSpaceComponentSpaceSimulation space
SimulationBaseBoneFBoneReference-Base bone for BaseBone space
TargetFramerateint3260Target framerate
OverrideTargetFramerateboolfalseOverride framerate
TeleportDistanceThresholdfloat300.0Teleport distance threshold
TeleportRotationThresholdfloat10.0Teleport rotation threshold
PlanarConstraintEPlanarConstraintNonePlanar constraint
SkelCompMoveScaleFVector(1, 1, 1)Component move scale

Warm-up Settings​

PropertyTypeDefaultDescription
WarmUpFramesint320Warm-up frame count
bNeedWarmUpboolfalseEnable warm-up
bUseWarmUpWhenResetDynamicsbooltrueWarm-up on reset

Curves​

PropertyTypeDescription
DampingCurveDataFRuntimeFloatCurveDamping curve
StiffnessCurveDataFRuntimeFloatCurveStiffness curve
WorldDampingLocationCurveDataFRuntimeFloatCurveWorld location damping curve
WorldDampingRotationCurveDataFRuntimeFloatCurveWorld rotation damping curve
RadiusCurveDataFRuntimeFloatCurveRadius curve
LimitAngleCurveDataFRuntimeFloatCurveAngle limit curve

Collision (Limits)​

PropertyTypeDescription
SphericalLimitsTArray<FSphericalLimit>Sphere collision
CapsuleLimitsTArray<FCapsuleLimit>Capsule collision
BoxLimitsTArray<FBoxLimit>Box collision
PlanarLimitsTArray<FPlanarLimit>Plane collision
LimitsDataAssetUKawaiiPhysicsLimitsDataAsset*Collision Data Asset
PhysicsAssetForLimitsUPhysicsAsset*Physics Asset for collision

Bone Constraint​

PropertyTypeDefaultDescription
BoneConstraintGlobalComplianceTypeEXPBDComplianceTypeLeatherCompliance type
BoneConstraintIterationCountBeforeCollisionint321Pre-collision iteration count
BoneConstraintIterationCountAfterCollisionint321Post-collision iteration count
bAutoAddChildDummyBoneConstraintbooltrueAuto-add dummy bone
BoneConstraintsTArray<FModifyBoneConstraint>-Bone constraint list
BoneConstraintsDataAssetUKawaiiPhysicsBoneConstraintsDataAsset*-Constraints Data Asset

Sync Bone​

PropertyTypeDescription
SyncBonesTArray<FKawaiiPhysicsSyncBone>Sync bone list

External Forces​

PropertyTypeDefaultDescription
GravityFVectorZeroVectorGravity vector
bUseLegacyGravityboolfalseLegacy gravity method
bUseDefaultGravityZProjectSettingboolfalseUse project setting gravity
bUseWorldSpaceGravitybooltrueWorld space gravity
bEnableWindboolfalseEnable wind
WindScalefloat1.0Wind scale
WindDirectionNoiseAnglefloat0.0Wind direction noise (degrees)
SimpleExternalForceFVectorZeroVectorSimple external force
bUseWorldSpaceSimpleExternalForcebooltrueWorld space external force
ExternalForcesTArray<FInstancedStruct>-External force presets
CustomExternalForcesTArray<UKawaiiPhysics_CustomExternalForce*>-Custom external forces

World Collision​

PropertyTypeDefaultDescription
bAllowWorldCollisionboolfalseEnable world collision
bOverrideCollisionParamsboolfalseOverride collision parameters
CollisionChannelSettingsFBodyInstance-Collision settings
bIgnoreSelfComponentbooltrueIgnore self collision
IgnoreBonesTArray<FBoneReference>-Ignore bones list
IgnoreBoneNamePrefixTArray<FName>-Ignore bone name prefix

Tag​

PropertyTypeDescription
KawaiiPhysicsTagFGameplayTagFiltering tag

Runtime Data​

PropertyTypeDescription
ModifyBonesTArray<FKawaiiPhysicsModifyBone>Physics-controlled bones
DeltaTimefloatFrame delta time

Key Methods​

Initialize_AnyThread​

virtual void Initialize_AnyThread(const FAnimationInitializeContext& Context) override;

Node initialization. Builds bone chain and initializes parameters.

CacheBones_AnyThread​

virtual void CacheBones_AnyThread(const FAnimationCacheBonesContext& Context) override;

Bone reference caching.

UpdateInternal​

virtual void UpdateInternal(const FAnimationUpdateContext& Context) override;

Per-frame update processing.

EvaluateSkeletalControl_AnyThread​

virtual void EvaluateSkeletalControl_AnyThread(
    FComponentSpacePoseContext& Output,
    TArray<FBoneTransform>& OutBoneTransforms
) override;

Physics simulation evaluation and bone transform output.

ResetDynamics​

virtual void ResetDynamics(ETeleportType InTeleportType) override;

Physics state reset. Used for teleportation, etc.

PreUpdate​

virtual void PreUpdate(const UAnimInstance* InAnimInstance) override;

Pre-update processing. Retrieves scene information, etc.

Coordinate Transform Helpers​

GetBoneTransformInSimSpace​

FTransform GetBoneTransformInSimSpace(
    FComponentSpacePoseContext& Output,
    const FCompactPoseBoneIndex& BoneIndex
) const;

Gets bone Transform in simulation space.

ConvertSimulationSpaceTransform​

FTransform ConvertSimulationSpaceTransform(
    FComponentSpacePoseContext& Output,
    EKawaiiPhysicsSimulationSpace From,
    EKawaiiPhysicsSimulationSpace To,
    const FTransform& InTransform
) const;

Converts Transform between simulation spaces.

Usage Example​

Basic usage in Animation Blueprint:

  1. Add KawaiiPhysics node to AnimGraph
  2. Set RootBone
  3. Adjust Damping/Stiffness in PhysicsSettings
  4. Add collision as needed
// Example accessing from C++
FAnimNode_KawaiiPhysics* Node = ...;
Node->PhysicsSettings.Damping = 0.2f;
Node->PhysicsSettings.Stiffness = 0.1f;
Node->Gravity = FVector(0, 0, -980.0f);