usdrt::UsdSkelBindingAPI

Defined in usdrt/scenegraph/usd/usdSkel/bindingAPI.h

class UsdSkelBindingAPI : public usdrt::UsdAPISchemaBase 

Provides API for authoring and extracting all the skinning-related data that lives in the “geometry hierarchy” of prims and models that want to be skeletally deformed.

See the extended UsdSkelBindingAPI schema documentation for more about bindings and how they apply in a scene graph.

For any described attribute Fallback Value or Allowed Values below that are text/tokens, the actual token is published and defined in UsdSkelTokens. So to set an attribute to the value “rightHanded”, use UsdSkelTokens->rightHanded as the value.

Public Functions

inline explicit UsdSkelBindingAPI(const UsdPrim &prim = UsdPrim()): Construct a UsdSkelBindingAPI on UsdPrim prim. Equivalent to UsdSkelBindingAPI::Get(prim.GetStage(), prim.GetPath()) for a valid prim , but will not immediately throw an error for an invalid prim.

inline explicit UsdSkelBindingAPI(const UsdSchemaBase &schemaObj): Construct a UsdSkelBindingAPI on the prim held by schemaObj . Should be preferred over UsdSkelBindingAPI(schemaObj.GetPrim()), as it preserves SchemaBase state.

inline virtual ~UsdSkelBindingAPI(): Destructor.

inline UsdAttribute GetGeomBindTransformAttr() const

Encodes the bind-time world space transforms of the prim. If the transform is identical for a group of gprims that share a common ancestor, the transform may be authored on the ancestor, to “inherit” down to all the leaf gprims. If this transform is unset, an identity transform is used instead.


Declaration	`matrix4d primvars:skel:geomBindTransform`
C++ Type	GfMatrix4d
Usd Type	SdfValueTypeNames->Matrix4d

inline UsdAttribute CreateGeomBindTransformAttr() const: See GetGeomBindTransformAttr(), and also Create vs Get Property Methods for when to use Get vs Create. If specified, author defaultValue as the attribute’s default, sparsely (when it makes sense to do so) if writeSparsely is true - the default for writeSparsely is false.

inline UsdAttribute GetJointsAttr() const

An (optional) array of tokens defining the list of joints to which jointIndices apply. If not defined, jointIndices applies to the ordered list of joints defined in the bound Skeleton’s joints attribute. If undefined on a primitive, the primitive inherits the value of the nearest ancestor prim, if any.


Declaration	`uniform token[] skel:joints`
C++ Type	VtArray<TfToken>
Usd Type	SdfValueTypeNames->TokenArray
Variability	SdfVariabilityUniform

inline UsdAttribute CreateJointsAttr() const: See GetJointsAttr(), and also Create vs Get Property Methods for when to use Get vs Create. If specified, author defaultValue as the attribute’s default, sparsely (when it makes sense to do so) if writeSparsely is true - the default for writeSparsely is false.

inline UsdAttribute GetJointIndicesAttr() const

Indices into the joints attribute of the closest (in namespace) bound Skeleton that affect each point of a PointBased gprim. The primvar can have either constant or vertex interpolation. This primvar’s elementSize will determine how many joint influences apply to each point. Indices must point be valid. Null influences should be defined by setting values in jointWeights to zero. See UsdGeomPrimvar for more information on interpolation and elementSize.


Declaration	`int[] primvars:skel:jointIndices`
C++ Type	VtArray<int>
Usd Type	SdfValueTypeNames->IntArray

inline UsdAttribute CreateJointIndicesAttr() const: See GetJointIndicesAttr(), and also Create vs Get Property Methods for when to use Get vs Create. If specified, author defaultValue as the attribute’s default, sparsely (when it makes sense to do so) if writeSparsely is true - the default for writeSparsely is false.

inline UsdAttribute GetJointWeightsAttr() const

Weights for the joints that affect each point of a PointBased gprim. The primvar can have either constant or vertex interpolation. This primvar’s elementSize will determine how many joints influences apply to each point. The length, interpolation, and elementSize of jointWeights must match that of jointIndices. See UsdGeomPrimvar for more information on interpolation and elementSize.


Declaration	`float[] primvars:skel:jointWeights`
C++ Type	VtArray<float>
Usd Type	SdfValueTypeNames->FloatArray

inline UsdAttribute CreateJointWeightsAttr() const: See GetJointWeightsAttr(), and also Create vs Get Property Methods for when to use Get vs Create. If specified, author defaultValue as the attribute’s default, sparsely (when it makes sense to do so) if writeSparsely is true - the default for writeSparsely is false.

inline UsdAttribute GetSkinningMethodAttr() const

Different calculation method for skinning. LBS, DQ, and blendWeight.


Declaration	`uniform token skel:skinningMethod = "ClassicLinear"`
C++ Type	TfToken
Usd Type	SdfValueTypeNames->Token
Variability	SdfVariabilityUniform
Allowed Values	ClassicLinear, DualQuaternion, WeightedBlend

inline UsdAttribute CreateSkinningMethodAttr() const: See GetSkinningMethodAttr(), and also Create vs Get Property Methods for when to use Get vs Create. If specified, author defaultValue as the attribute’s default, sparsely (when it makes sense to do so) if writeSparsely is true - the default for writeSparsely is false.

inline UsdAttribute GetSkinningBlendWeightsAttr() const

Weights for weighted blend skinning method. The primvar can have either constant or vertex interpolation. Constant interpolation means every vertex share the same single blend weight. Vertex interpolation means every vertex has their own blend weight. The element size should match the vertices count in this case.


Declaration	`uniform float[] primvars:skel:skinningBlendWeights`
C++ Type	VtArray<float>
Usd Type	SdfValueTypeNames->FloatArray
Variability	SdfVariabilityUniform

inline UsdAttribute CreateSkinningBlendWeightsAttr() const: See GetSkinningBlendWeightsAttr(), and also Create vs Get Property Methods for when to use Get vs Create. If specified, author defaultValue as the attribute’s default, sparsely (when it makes sense to do so) if writeSparsely is true - the default for writeSparsely is false.

inline UsdAttribute GetBlendShapesAttr() const

An array of tokens defining the order onto which blend shape weights from an animation source map onto the skel:blendShapeTargets rel of a binding site. If authored, the number of elements must be equal to the number of targets in the blendShapeTargets rel. This property is not inherited hierarchically, and is expected to be authored directly on the skinnable primitive to which the blend shapes apply.


Declaration	`uniform token[] skel:blendShapes`
C++ Type	VtArray<TfToken>
Usd Type	SdfValueTypeNames->TokenArray
Variability	SdfVariabilityUniform

inline UsdAttribute CreateBlendShapesAttr() const: See GetBlendShapesAttr(), and also Create vs Get Property Methods for when to use Get vs Create. If specified, author defaultValue as the attribute’s default, sparsely (when it makes sense to do so) if writeSparsely is true - the default for writeSparsely is false.

inline UsdRelationship GetAnimationSourceRel() const: Animation source to be bound to Skeleton primitives at or beneath the location at which this property is defined.

inline UsdRelationship CreateAnimationSourceRel() const: See GetAnimationSourceRel(), and also Create vs Get Property Methods for when to use Get vs Create.

inline UsdRelationship GetSkeletonRel() const: Skeleton to be bound to this prim and its descendents that possess a mapping and weighting to the joints of the identified Skeleton.

inline UsdRelationship CreateSkeletonRel() const: See GetSkeletonRel(), and also Create vs Get Property Methods for when to use Get vs Create.

inline UsdRelationship GetBlendShapeTargetsRel() const: Ordered list of all target blend shapes. This property is not inherited hierarchically, and is expected to be authored directly on the skinnable primitive to which the the blend shapes apply.

inline UsdRelationship CreateBlendShapeTargetsRel() const: See GetBlendShapeTargetsRel(), and also Create vs Get Property Methods for when to use Get vs Create.

UsdPrim GetPrim() const: Return this schema object’s held prim.

SdfPath GetPath() const: Return the SdfPath to this schema object’s held prim.

inline explicit operator bool() const

Check if this schema object is compatible with it’s held prim and that the prim is valid.

A typed schema object is compatible if the held prim’s type is or is a subtype of the schema’s type. Based on prim.IsA().

An API schema object is compatible if the API is of type SingleApplyAPI or UsdSchemaType::MultipleApplyAPI, and the schema has been applied to the prim. Based on prim.HasAPI.

This method invokes polymorphic behaviour.

See also

UsdSchemaBase::_IsCompatible()

Returns: True if the help prim is valid, and the schema object is compatible with its held prim.

Public Static Functions

static inline UsdSkelBindingAPI Apply(const UsdPrim &prim)

Applies this single-apply API schema to the given prim. This information is stored by adding “SkelBindingAPI” to the token-valued, listOp metadata apiSchemas on the prim.

See also

UsdPrim::GetAppliedSchemas()

See also

UsdPrim::HasAPI()

See also

UsdPrim::ApplyAPI()

See also

UsdPrim::RemoveAPI()

Returns: A valid UsdSkelBindingAPI object is returned upon success. An invalid (or empty) UsdSkelBindingAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure.

Public Static Attributes

static const UsdSchemaType schemaType = UsdSchemaType::SingleApplyAPI 

Compile time constant representing what kind of schema this class is.

See also

UsdSchemaType

Protected Functions

inline const TfToken &_GetInstanceName() const

Returns the instance name of the API schema object belonging to a multiple-apply API schema.

The returned instance name will be empty for non-applied and single-apply API schemas.

inline virtual bool _IsCompatible() const

Check whether this APISchema object is valid for the currently held prim.

If this is an applied API schema, this returns true if the held prim is valid and already has the API schema applied to it, along with the instanceName (in the case of multiple-apply). The instanceName should not be empty in the case of a multiple-apply API schema.

This check is performed when clients invoke the explicit bool conversion operator, implemented in UsdSchemaBase.

See also

UsdPrim::HasAPI()

inline const TfToken _GetType() const

Helper for subclasses to get this schema’s type token.

Note

This diverges from Usd and returns a TfToken, since we don’t implements TfType.

Returns: The token representing the schema’s TfType.