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UsdGeomBasisCurves Class Reference

BasisCurves are a batched curve representation analogous to the classic RIB definition via Basis and Curves statements. More...

#include <basisCurves.h>

+ Inheritance diagram for UsdGeomBasisCurves:

Public Member Functions

 UsdGeomBasisCurves (const UsdPrim &prim=UsdPrim())
 Construct a UsdGeomBasisCurves on UsdPrim prim .
 
 UsdGeomBasisCurves (const UsdSchemaBase &schemaObj)
 Construct a UsdGeomBasisCurves on the prim held by schemaObj .
 
virtual USDGEOM_API ~UsdGeomBasisCurves ()
 Destructor.
 
USDGEOM_API UsdAttribute GetTypeAttr () const
 Linear curves interpolate linearly between two vertices.
 
USDGEOM_API UsdAttribute CreateTypeAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetTypeAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetBasisAttr () const
 The basis specifies the vstep and matrix used for cubic interpolation.
 
USDGEOM_API UsdAttribute CreateBasisAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetBasisAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetWrapAttr () const
 If wrap is set to periodic, the curve when rendered will repeat the initial vertices (dependent on the vstep) to close the curve.
 
USDGEOM_API UsdAttribute CreateWrapAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetWrapAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
- Public Member Functions inherited from UsdGeomCurves
 UsdGeomCurves (const UsdPrim &prim=UsdPrim())
 Construct a UsdGeomCurves on UsdPrim prim .
 
 UsdGeomCurves (const UsdSchemaBase &schemaObj)
 Construct a UsdGeomCurves on the prim held by schemaObj .
 
virtual USDGEOM_API ~UsdGeomCurves ()
 Destructor.
 
USDGEOM_API UsdAttribute GetCurveVertexCountsAttr () const
 Curves-derived primitives can represent multiple distinct, potentially disconnected curves.
 
USDGEOM_API UsdAttribute CreateCurveVertexCountsAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetCurveVertexCountsAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetWidthsAttr () const
 Provides width specification for the curves, whose application will depend on whether the curve is oriented (normals are defined for it), in which case widths are "ribbon width", or unoriented, in which case widths are cylinder width.
 
USDGEOM_API UsdAttribute CreateWidthsAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetWidthsAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API TfToken GetWidthsInterpolation () const
 Get the interpolation for the widths attribute.
 
USDGEOM_API bool SetWidthsInterpolation (TfToken const &interpolation)
 Set the interpolation for the widths attribute.
 
USDGEOM_API size_t GetCurveCount (UsdTimeCode timeCode=UsdTimeCode::Default()) const
 Returns the number of curves as defined by the size of the curveVertexCounts array at timeCode.
 
- Public Member Functions inherited from UsdGeomPointBased
 UsdGeomPointBased (const UsdPrim &prim=UsdPrim())
 Construct a UsdGeomPointBased on UsdPrim prim .
 
 UsdGeomPointBased (const UsdSchemaBase &schemaObj)
 Construct a UsdGeomPointBased on the prim held by schemaObj .
 
virtual USDGEOM_API ~UsdGeomPointBased ()
 Destructor.
 
USDGEOM_API UsdAttribute GetPointsAttr () const
 The primary geometry attribute for all PointBased primitives, describes points in (local) space.
 
USDGEOM_API UsdAttribute CreatePointsAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetPointsAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetVelocitiesAttr () const
 If provided, 'velocities' should be used by renderers to.
 
USDGEOM_API UsdAttribute CreateVelocitiesAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetVelocitiesAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetAccelerationsAttr () const
 If provided, 'accelerations' should be used with velocities to compute positions between samples for the 'points' attribute rather than interpolating between neighboring 'points' samples.
 
USDGEOM_API UsdAttribute CreateAccelerationsAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetAccelerationsAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetNormalsAttr () const
 Provide an object-space orientation for individual points, which, depending on subclass, may define a surface, curve, or free points.
 
USDGEOM_API UsdAttribute CreateNormalsAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetNormalsAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API TfToken GetNormalsInterpolation () const
 Get the interpolation for the normals attribute.
 
USDGEOM_API bool SetNormalsInterpolation (TfToken const &interpolation)
 Set the interpolation for the normals attribute.
 
USDGEOM_API bool ComputePointsAtTime (VtArray< GfVec3f > *points, const UsdTimeCode time, const UsdTimeCode baseTime) const
 Compute points given the positions, velocities and accelerations at time.
 
USDGEOM_API bool ComputePointsAtTimes (std::vector< VtArray< GfVec3f > > *pointsArray, const std::vector< UsdTimeCode > &times, const UsdTimeCode baseTime) const
 Compute points as in ComputePointsAtTime, but using multiple sample times.
 
- Public Member Functions inherited from UsdGeomGprim
 UsdGeomGprim (const UsdPrim &prim=UsdPrim())
 Construct a UsdGeomGprim on UsdPrim prim .
 
 UsdGeomGprim (const UsdSchemaBase &schemaObj)
 Construct a UsdGeomGprim on the prim held by schemaObj .
 
virtual USDGEOM_API ~UsdGeomGprim ()
 Destructor.
 
USDGEOM_API UsdAttribute GetDisplayColorAttr () const
 It is useful to have an "official" colorSet that can be used as a display or modeling color, even in the absence of any specified shader for a gprim.
 
USDGEOM_API UsdAttribute CreateDisplayColorAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetDisplayColorAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetDisplayOpacityAttr () const
 Companion to displayColor that specifies opacity, broken out as an independent attribute rather than an rgba color, both so that each can be independently overridden, and because shaders rarely consume rgba parameters.
 
USDGEOM_API UsdAttribute CreateDisplayOpacityAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetDisplayOpacityAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetDoubleSidedAttr () const
 Although some renderers treat all parametric or polygonal surfaces as if they were effectively laminae with outward-facing normals on both sides, some renderers derive significant optimizations by considering these surfaces to have only a single outward side, typically determined by control-point winding order and/or orientation.
 
USDGEOM_API UsdAttribute CreateDoubleSidedAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetDoubleSidedAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetOrientationAttr () const
 Orientation specifies whether the gprim's surface normal should be computed using the right hand rule, or the left hand rule.
 
USDGEOM_API UsdAttribute CreateOrientationAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetOrientationAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdGeomPrimvar GetDisplayColorPrimvar () const
 Convenience function to get the displayColor Attribute as a Primvar.
 
USDGEOM_API UsdGeomPrimvar CreateDisplayColorPrimvar (const TfToken &interpolation=TfToken(), int elementSize=-1) const
 Convenience function to create the displayColor primvar, optionally specifying interpolation and elementSize.
 
USDGEOM_API UsdGeomPrimvar GetDisplayOpacityPrimvar () const
 Convenience function to get the displayOpacity Attribute as a Primvar.
 
USDGEOM_API UsdGeomPrimvar CreateDisplayOpacityPrimvar (const TfToken &interpolation=TfToken(), int elementSize=-1) const
 Convenience function to create the displayOpacity primvar, optionally specifying interpolation and elementSize.
 
- Public Member Functions inherited from UsdGeomBoundable
 UsdGeomBoundable (const UsdPrim &prim=UsdPrim())
 Construct a UsdGeomBoundable on UsdPrim prim .
 
 UsdGeomBoundable (const UsdSchemaBase &schemaObj)
 Construct a UsdGeomBoundable on the prim held by schemaObj .
 
virtual USDGEOM_API ~UsdGeomBoundable ()
 Destructor.
 
USDGEOM_API UsdAttribute GetExtentAttr () const
 Extent is a three dimensional range measuring the geometric extent of the authored gprim in its own local space (i.e.
 
USDGEOM_API UsdAttribute CreateExtentAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetExtentAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API bool ComputeExtent (const UsdTimeCode &time, VtVec3fArray *extent) const
 If an extent is authored on this boundable, it queries the extent from the extent attribute, otherwise if ComputeExtentFunction is registered for the boundable's type, it computes the extent at time.
 
- Public Member Functions inherited from UsdGeomXformable
 UsdGeomXformable (const UsdPrim &prim=UsdPrim())
 Construct a UsdGeomXformable on UsdPrim prim .
 
 UsdGeomXformable (const UsdSchemaBase &schemaObj)
 Construct a UsdGeomXformable on the prim held by schemaObj .
 
virtual USDGEOM_API ~UsdGeomXformable ()
 Destructor.
 
USDGEOM_API UsdAttribute GetXformOpOrderAttr () const
 Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims.
 
USDGEOM_API UsdAttribute CreateXformOpOrderAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetXformOpOrderAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdGeomXformOp AddXformOp (UsdGeomXformOp::Type const opType, UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionDouble, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add an affine transformation to the local stack represented by this Xformable.
 
USDGEOM_API UsdGeomXformOp GetXformOp (UsdGeomXformOp::Type const opType, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get an affine transformation from the local stack represented by this Xformable.
 
USDGEOM_API UsdGeomXformOp AddTranslateOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionDouble, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a translate operation to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetTranslateOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a translate operation from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddScaleOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a scale operation to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetScaleOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a scale operation from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateXOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation about the X-axis to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateXOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation about the X-axis from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateYOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation about the Y-axis to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateYOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation about the Y-axis from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateZOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation about the Z-axis to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateZOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation about the Z-axis from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateXYZOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation op with XYZ rotation order to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateXYZOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation op with XYZ rotation order from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateXZYOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation op with XZY rotation order to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateXZYOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation op with XZY rotation order from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateYXZOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation op with YXZ rotation order to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateYXZOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation op with YXZ rotation order from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateYZXOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation op with YZX rotation order to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateYZXOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation op with YZX rotation order from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateZXYOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation op with ZXY rotation order to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateZXYOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation op with ZXY rotation order from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddRotateZYXOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a rotation op with ZYX rotation order to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetRotateZYXOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a rotation op with ZYX rotation order from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddOrientOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionFloat, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a orient op (arbitrary axis/angle rotation) to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetOrientOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get an orient op (arbitrary axis/angle rotation) from the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp AddTransformOp (UsdGeomXformOp::Precision const precision=UsdGeomXformOp::PrecisionDouble, TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Add a tranform op (4x4 matrix transformation) to the local stack represented by this xformable.
 
USDGEOM_API UsdGeomXformOp GetTransformOp (TfToken const &opSuffix=TfToken(), bool isInverseOp=false) const
 Get a tranform op (4x4 matrix transformation) from the local stack represented by this xformable.
 
USDGEOM_API bool SetResetXformStack (bool resetXform) const
 Specify whether this prim's transform should reset the transformation stack inherited from its parent prim.
 
USDGEOM_API bool GetResetXformStack () const
 Does this prim reset its parent's inherited transformation?
 
USDGEOM_API bool SetXformOpOrder (std::vector< UsdGeomXformOp > const &orderedXformOps, bool resetXformStack=false) const
 Reorder the already-existing transform ops on this prim.
 
USDGEOM_API std::vector< UsdGeomXformOpGetOrderedXformOps (bool *resetsXformStack) const
 Return the ordered list of transform operations to be applied to this prim, in least-to-most-local order.
 
USDGEOM_API bool ClearXformOpOrder () const
 Clears the local transform stack.
 
USDGEOM_API UsdGeomXformOp MakeMatrixXform () const
 Clears the existing local transform stack and creates a new xform op of type 'transform'.
 
USDGEOM_API bool TransformMightBeTimeVarying () const
 Determine whether there is any possibility that this prim's local transformation may vary over time.
 
USDGEOM_API bool TransformMightBeTimeVarying (const std::vector< UsdGeomXformOp > &ops) const
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Determine whether there is any possibility that this prim's local transformation may vary over time, using a pre-fetched (cached) list of ordered xform ops supplied by the client.
 
USDGEOM_API bool GetTimeSamples (std::vector< double > *times) const
 Sets times to the union of all the timesamples at which xformOps that are included in the xformOpOrder attribute are authored.
 
USDGEOM_API bool GetTimeSamplesInInterval (const GfInterval &interval, std::vector< double > *times) const
 Sets times to the union of all the timesamples in the interval, interval, at which xformOps that are included in the xformOpOrder attribute are authored.
 
USDGEOM_API bool GetLocalTransformation (GfMatrix4d *transform, bool *resetsXformStack, const UsdTimeCode time=UsdTimeCode::Default()) const
 Computes the fully-combined, local-to-parent transformation for this prim.
 
USDGEOM_API bool GetLocalTransformation (GfMatrix4d *transform, bool *resetsXformStack, const std::vector< UsdGeomXformOp > &ops, const UsdTimeCode time=UsdTimeCode::Default()) const
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Computes the fully-combined, local-to-parent transformation for this prim as efficiently as possible, using a pre-fetched (cached) list of ordered xform ops supplied by the client.
 
- Public Member Functions inherited from UsdGeomImageable
 UsdGeomImageable (const UsdPrim &prim=UsdPrim())
 Construct a UsdGeomImageable on UsdPrim prim .
 
 UsdGeomImageable (const UsdSchemaBase &schemaObj)
 Construct a UsdGeomImageable on the prim held by schemaObj .
 
virtual USDGEOM_API ~UsdGeomImageable ()
 Destructor.
 
USDGEOM_API UsdAttribute GetVisibilityAttr () const
 Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps.
 
USDGEOM_API UsdAttribute CreateVisibilityAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetVisibilityAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdAttribute GetPurposeAttr () const
 Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals.
 
USDGEOM_API UsdAttribute CreatePurposeAttr (VtValue const &defaultValue=VtValue(), bool writeSparsely=false) const
 See GetPurposeAttr(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API UsdRelationship GetProxyPrimRel () const
 The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim.
 
USDGEOM_API UsdRelationship CreateProxyPrimRel () const
 See GetProxyPrimRel(), and also Create vs Get Property Methods for when to use Get vs Create.
 
USDGEOM_API void MakeVisible (const UsdTimeCode &time=UsdTimeCode::Default()) const
 Make the imageable visible if it is invisible at the given time.
 
USDGEOM_API void MakeInvisible (const UsdTimeCode &time=UsdTimeCode::Default()) const
 Makes the imageable invisible if it is visible at the given time.
 
USDGEOM_API TfToken ComputeVisibility (UsdTimeCode const &time=UsdTimeCode::Default()) const
 Calculate the effective visibility of this prim, as defined by its most ancestral authored "invisible" opinion, if any.
 
USDGEOM_API UsdAttribute GetPurposeVisibilityAttr (const TfToken &purpose=UsdGeomTokens->default_) const
 Return the attribute that is used for expressing visibility opinions for the given purpose.
 
USDGEOM_API TfToken ComputeEffectiveVisibility (const TfToken &purpose=UsdGeomTokens->default_, const UsdTimeCode &time=UsdTimeCode::Default()) const
 Calculate the effective purpose visibility of this prim for the given purpose, taking into account opinions for the corresponding purpose attribute, along with overall visibility opinions.
 
USDGEOM_API PurposeInfo ComputePurposeInfo () const
 Calculate the effective purpose information about this prim which includes final computed purpose value of the prim as well as whether the purpose value should be inherited by namespace children without their own purpose opinions.
 
USDGEOM_API PurposeInfo ComputePurposeInfo (const PurposeInfo &parentPurposeInfo) const
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Calculates the effective purpose information about this prim, given the computed purpose information of its parent prim.
 
USDGEOM_API TfToken ComputePurpose () const
 Calculate the effective purpose information about this prim.
 
USDGEOM_API UsdPrim ComputeProxyPrim (UsdPrim *renderPrim=NULL) const
 Find the prim whose purpose is proxy that serves as the proxy for this prim, as established by the GetProxyPrimRel(), or an invalid UsdPrim if this prim has no proxy.
 
USDGEOM_API bool SetProxyPrim (const UsdPrim &proxy) const
 Convenience function for authoring the renderProxy rel on this prim to target the given proxy prim.
 
USDGEOM_API bool SetProxyPrim (const UsdSchemaBase &proxy) const
 
USDGEOM_API GfBBox3d ComputeWorldBound (UsdTimeCode const &time, TfToken const &purpose1=TfToken(), TfToken const &purpose2=TfToken(), TfToken const &purpose3=TfToken(), TfToken const &purpose4=TfToken()) const
 Compute the bound of this prim in world space, at the specified time, and for the specified purposes.
 
USDGEOM_API GfBBox3d ComputeLocalBound (UsdTimeCode const &time, TfToken const &purpose1=TfToken(), TfToken const &purpose2=TfToken(), TfToken const &purpose3=TfToken(), TfToken const &purpose4=TfToken()) const
 Compute the bound of this prim in local space, at the specified time, and for the specified purposes.
 
USDGEOM_API GfBBox3d ComputeUntransformedBound (UsdTimeCode const &time, TfToken const &purpose1=TfToken(), TfToken const &purpose2=TfToken(), TfToken const &purpose3=TfToken(), TfToken const &purpose4=TfToken()) const
 Compute the untransformed bound of this prim, at the specified time, and for the specified purposes.
 
USDGEOM_API GfMatrix4d ComputeLocalToWorldTransform (UsdTimeCode const &time) const
 Compute the transformation matrix for this prim at the given time, including the transform authored on the Prim itself, if present.
 
USDGEOM_API GfMatrix4d ComputeParentToWorldTransform (UsdTimeCode const &time) const
 Compute the transformation matrix for this prim at the given time, NOT including the transform authored on the prim itself.
 
- Public Member Functions inherited from UsdTyped
 UsdTyped (const UsdPrim &prim=UsdPrim())
 Construct a UsdTyped on UsdPrim prim .
 
 UsdTyped (const UsdSchemaBase &schemaObj)
 Construct a UsdTyped on the prim held by schemaObj .
 
virtual USD_API ~UsdTyped ()
 Destructor.
 
- Public Member Functions inherited from UsdSchemaBase
bool IsConcrete () const
 Returns whether or not this class corresponds to a concrete instantiable prim type in scene description.
 
bool IsTyped () const
 Returns whether or not this class inherits from UsdTyped.
 
bool IsAPISchema () const
 Returns whether this is an API schema or not.
 
bool IsAppliedAPISchema () const
 Returns whether this is an applied API schema or not.
 
bool IsMultipleApplyAPISchema () const
 Returns whether this is an applied API schema or not.
 
UsdSchemaKind GetSchemaKind () const
 Returns the kind of schema this class is.
 
USD_API UsdSchemaBase (const UsdPrim &prim=UsdPrim())
 Construct and store prim as the held prim.
 
USD_API UsdSchemaBase (const UsdSchemaBase &otherSchema)
 Construct and store for the same prim held by otherSchema.
 
virtual USD_API ~UsdSchemaBase ()
 Destructor.
 
UsdPrim GetPrim () const
 Return this schema object's held prim.
 
SdfPath GetPath () const
 Shorthand for GetPrim()->GetPath().
 
USD_API const UsdPrimDefinitionGetSchemaClassPrimDefinition () const
 Return the prim definition associated with this schema instance if one exists, otherwise return null.
 
USD_API operator bool () const
 Return true if this schema object is compatible with its held prim, false otherwise.
 

Static Public Member Functions

static USDGEOM_API const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.
 
static USDGEOM_API UsdGeomBasisCurves Get (const UsdStagePtr &stage, const SdfPath &path)
 Return a UsdGeomBasisCurves holding the prim adhering to this schema at path on stage.
 
static USDGEOM_API UsdGeomBasisCurves Define (const UsdStagePtr &stage, const SdfPath &path)
 Attempt to ensure a UsdPrim adhering to this schema at path is defined (according to UsdPrim::IsDefined()) on this stage.
 
- Static Public Member Functions inherited from UsdGeomCurves
static USDGEOM_API const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.
 
static USDGEOM_API UsdGeomCurves Get (const UsdStagePtr &stage, const SdfPath &path)
 Return a UsdGeomCurves holding the prim adhering to this schema at path on stage.
 
static USDGEOM_API bool ComputeExtent (const VtVec3fArray &points, const VtFloatArray &widths, VtVec3fArray *extent)
 Compute the extent for the curves defined by points and widths.
 
static USDGEOM_API bool ComputeExtent (const VtVec3fArray &points, const VtFloatArray &widths, const GfMatrix4d &transform, VtVec3fArray *extent)
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Computes the extent as if the matrix transform was first applied.
 
- Static Public Member Functions inherited from UsdGeomPointBased
static USDGEOM_API const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.
 
static USDGEOM_API UsdGeomPointBased Get (const UsdStagePtr &stage, const SdfPath &path)
 Return a UsdGeomPointBased holding the prim adhering to this schema at path on stage.
 
static USDGEOM_API bool ComputeExtent (const VtVec3fArray &points, VtVec3fArray *extent)
 Compute the extent for the point cloud defined by points.
 
static USDGEOM_API bool ComputeExtent (const VtVec3fArray &points, const GfMatrix4d &transform, VtVec3fArray *extent)
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Computes the extent as if the matrix transform was first applied.
 
static USDGEOM_API bool ComputePointsAtTime (VtArray< GfVec3f > *points, UsdStageWeakPtr &stage, UsdTimeCode time, const VtVec3fArray &positions, const VtVec3fArray &velocities, UsdTimeCode velocitiesSampleTime, const VtVec3fArray &accelerations, float velocityScale=1.0)
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Perform the point computation.
 
- Static Public Member Functions inherited from UsdGeomGprim
static USDGEOM_API const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.
 
static USDGEOM_API UsdGeomGprim Get (const UsdStagePtr &stage, const SdfPath &path)
 Return a UsdGeomGprim holding the prim adhering to this schema at path on stage.
 
- Static Public Member Functions inherited from UsdGeomBoundable
static USDGEOM_API const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.
 
static USDGEOM_API UsdGeomBoundable Get (const UsdStagePtr &stage, const SdfPath &path)
 Return a UsdGeomBoundable holding the prim adhering to this schema at path on stage.
 
static USDGEOM_API bool ComputeExtentFromPlugins (const UsdGeomBoundable &boundable, const UsdTimeCode &time, VtVec3fArray *extent)
 Compute the extent for the Boundable prim boundable at time time.
 
static USDGEOM_API bool ComputeExtentFromPlugins (const UsdGeomBoundable &boundable, const UsdTimeCode &time, const GfMatrix4d &transform, VtVec3fArray *extent)
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Computes the extent as if the matrix transform was first applied.
 
- Static Public Member Functions inherited from UsdGeomXformable
static USDGEOM_API const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.
 
static USDGEOM_API UsdGeomXformable Get (const UsdStagePtr &stage, const SdfPath &path)
 Return a UsdGeomXformable holding the prim adhering to this schema at path on stage.
 
static USDGEOM_API bool GetTimeSamples (std::vector< UsdGeomXformOp > const &orderedXformOps, std::vector< double > *times)
 Returns the union of all the timesamples at which the attributes belonging to the given orderedXformOps are authored.
 
static USDGEOM_API bool GetTimeSamplesInInterval (std::vector< UsdGeomXformOp > const &orderedXformOps, const GfInterval &interval, std::vector< double > *times)
 Returns the union of all the timesamples in the interval at which the attributes belonging to the given orderedXformOps are authored.
 
static USDGEOM_API bool GetLocalTransformation (GfMatrix4d *transform, std::vector< UsdGeomXformOp > const &ops, const UsdTimeCode time)
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. This is a static version of the preceding function that takes a cached list of ordered xform ops.
 
static USDGEOM_API bool IsTransformationAffectedByAttrNamed (const TfToken &attrName)
 Returns true if the attribute named attrName could affect the local transformation of an xformable prim.
 
- Static Public Member Functions inherited from UsdGeomImageable
static USDGEOM_API const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.
 
static USDGEOM_API UsdGeomImageable Get (const UsdStagePtr &stage, const SdfPath &path)
 Return a UsdGeomImageable holding the prim adhering to this schema at path on stage.
 
static USDGEOM_API const TfTokenVectorGetOrderedPurposeTokens ()
 Returns an ordered list of allowed values of the purpose attribute.
 
- Static Public Member Functions inherited from UsdTyped
static USD_API const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.
 
static USD_API UsdTyped Get (const UsdStagePtr &stage, const SdfPath &path)
 Return a UsdTyped holding the prim adhering to this schema at path on stage.
 
- Static Public Member Functions inherited from UsdSchemaBase
static const TfTokenVectorGetSchemaAttributeNames (bool includeInherited=true)
 

Static Public Attributes

static const UsdSchemaKind schemaKind = UsdSchemaKind::ConcreteTyped
 Compile time constant representing what kind of schema this class is.
 
- Static Public Attributes inherited from UsdGeomCurves
static const UsdSchemaKind schemaKind = UsdSchemaKind::AbstractTyped
 Compile time constant representing what kind of schema this class is.
 
- Static Public Attributes inherited from UsdGeomPointBased
static const UsdSchemaKind schemaKind = UsdSchemaKind::AbstractTyped
 Compile time constant representing what kind of schema this class is.
 
- Static Public Attributes inherited from UsdGeomGprim
static const UsdSchemaKind schemaKind = UsdSchemaKind::AbstractTyped
 Compile time constant representing what kind of schema this class is.
 
- Static Public Attributes inherited from UsdGeomBoundable
static const UsdSchemaKind schemaKind = UsdSchemaKind::AbstractTyped
 Compile time constant representing what kind of schema this class is.
 
- Static Public Attributes inherited from UsdGeomXformable
static const UsdSchemaKind schemaKind = UsdSchemaKind::AbstractTyped
 Compile time constant representing what kind of schema this class is.
 
- Static Public Attributes inherited from UsdGeomImageable
static const UsdSchemaKind schemaKind = UsdSchemaKind::AbstractTyped
 Compile time constant representing what kind of schema this class is.
 
- Static Public Attributes inherited from UsdTyped
static const UsdSchemaKind schemaKind = UsdSchemaKind::AbstractBase
 Compile time constant representing what kind of schema this class is.
 
- Static Public Attributes inherited from UsdSchemaBase
static const UsdSchemaKind schemaKind = UsdSchemaKind::AbstractBase
 Compile time constant representing what kind of schema this class is.
 

Protected Member Functions

USDGEOM_API UsdSchemaKind _GetSchemaKind () const override
 Returns the kind of schema this class belongs to.
 
- Protected Member Functions inherited from UsdGeomCurves
USDGEOM_API UsdSchemaKind _GetSchemaKind () const override
 Returns the kind of schema this class belongs to.
 
- Protected Member Functions inherited from UsdGeomPointBased
USDGEOM_API UsdSchemaKind _GetSchemaKind () const override
 Returns the kind of schema this class belongs to.
 
USDGEOM_API UsdSchemaKind _GetSchemaKind () const override
 Returns the kind of schema this class belongs to.
 
USDGEOM_API UsdSchemaKind _GetSchemaKind () const override
 Returns the kind of schema this class belongs to.
 
- Protected Member Functions inherited from UsdGeomXformable
USDGEOM_API UsdSchemaKind _GetSchemaKind () const override
 Returns the kind of schema this class belongs to.
 
USDGEOM_API UsdSchemaKind _GetSchemaKind () const override
 Returns the kind of schema this class belongs to.
 
- Protected Member Functions inherited from UsdTyped
USD_API UsdSchemaKind _GetSchemaKind () const override
 Returns the kind of schema this class belongs to.
 
USD_API bool _IsCompatible () const override
 Subclasses may override _IsCompatible to do specific compatibility checking with the given prim, such as type compatibility or value compatibility.
 
- Protected Member Functions inherited from UsdSchemaBase
virtual UsdSchemaKind _GetSchemaType () const
 
const TfType_GetType () const
 
USD_API UsdAttribute _CreateAttr (TfToken const &attrName, SdfValueTypeName const &typeName, bool custom, SdfVariability variability, VtValue const &defaultValue, bool writeSparsely) const
 

Friends

class UsdSchemaRegistry
 

Helper functions for working with UsdGeomCurves

typedef std::vector< std::pair< TfToken, size_t > > ComputeInterpolationInfo
 
USDGEOM_API TfToken ComputeInterpolationForSize (size_t n, const UsdTimeCode &timeCode, ComputeInterpolationInfo *info=NULL) const
 Computes interpolation token for n.
 
USDGEOM_API size_t ComputeUniformDataSize (const UsdTimeCode &timeCode) const
 Computes the expected size for data with "uniform" interpolation.
 
USDGEOM_API size_t ComputeVaryingDataSize (const UsdTimeCode &timeCode) const
 Computes the expected size for data with "varying" interpolation.
 
USDGEOM_API size_t ComputeVertexDataSize (const UsdTimeCode &timeCode) const
 Computes the expected size for data with "vertex" interpolation.
 
USDGEOM_API VtIntArray ComputeSegmentCounts (const UsdTimeCode &timeCode) const
 Computes the segment counts of the curves based on their vertex counts from the curveVertexCounts attribute.
 

Detailed Description

BasisCurves are a batched curve representation analogous to the classic RIB definition via Basis and Curves statements.

BasisCurves are often used to render dense aggregate geometry like hair or grass.

A 'matrix' and 'vstep' associated with the basis are used to interpolate the vertices of a cubic BasisCurves. (The basis attribute is unused for linear BasisCurves.)

A single prim may have many curves whose count is determined implicitly by the length of the curveVertexCounts vector. Each individual curve is composed of one or more segments. Each segment is defined by four vertices for cubic curves and two vertices for linear curves. See the next section for more information on how to map curve vertex counts to segment counts.

Segment Indexing

Interpolating a curve requires knowing how to decompose it into its individual segments.

The segments of a cubic curve are determined by the vertex count, the wrap (periodicity), and the vstep of the basis. For linear curves, the basis token is ignored and only the vertex count and wrap are needed.

cubic basis vstep
bezier 3
catmullRom 1
bspline 1

The first segment of a cubic (nonperiodic) curve is always defined by its first four points. The vstep is the increment used to determine what vertex indices define the next segment. For a two segment (nonperiodic) bspline basis curve (vstep = 1), the first segment will be defined by interpolating vertices [0, 1, 2, 3] and the second segment will be defined by [1, 2, 3, 4]. For a two segment bezier basis curve (vstep = 3), the first segment will be defined by interpolating vertices [0, 1, 2, 3] and the second segment will be defined by [3, 4, 5, 6]. If the vstep is not one, then you must take special care to make sure that the number of cvs properly divides by your vstep. (The indices described are relative to the initial vertex index for a batched curve.)

For periodic curves, at least one of the curve's initial vertices are repeated to close the curve. For cubic curves, the number of vertices repeated is '4 - vstep'. For linear curves, only one vertex is repeated to close the loop.

Pinned curves are a special case of nonperiodic curves that only affects the behavior of cubic Bspline and Catmull-Rom curves. To evaluate or render pinned curves, a client must effectively add 'phantom points' at the beginning and end of every curve in a batch. These phantom points are injected to ensure that the interpolated curve begins at P[0] and ends at P[n-1].

For a curve with initial point P[0] and last point P[n-1], the phantom points are defined as. P[-1] = 2 * P[0] - P[1] P[n] = 2 * P[n-1] - P[n-2]

Pinned cubic curves will (usually) have to be unpacked into the standard nonperiodic representation before rendering. This unpacking can add some additional overhead. However, using pinned curves reduces the amount of data recorded in a scene and (more importantly) better records the authors' intent for interchange.

Note
The additional phantom points mean that the minimum curve vertex count for cubic bspline and catmullRom curves is 2.

Linear curve segments are defined by two vertices. A two segment linear curve's first segment would be defined by interpolating vertices [0, 1]. The second segment would be defined by vertices [1, 2]. (Again, for a batched curve, indices are relative to the initial vertex index.)

When validating curve topology, each renderable entry in the curveVertexCounts vector must pass this check.

type wrap validitity
linear nonperiodic curveVertexCounts[i] > 2
linear periodic curveVertexCounts[i] > 3
cubic nonperiodic (curveVertexCounts[i] - 4) % vstep == 0
cubic periodic (curveVertexCounts[i]) % vstep == 0
cubic pinned (catmullRom/bspline) (curveVertexCounts[i] - 2) >= 0

Cubic Vertex Interpolation

Linear Vertex Interpolation

Linear interpolation is always used on curves of type linear. 't' with domain [0, 1], the curve is defined by the equation P0 * (1-t) + P1 * t. t at 0 describes the first point and t at 1 describes the end point.

Primvar Interpolation

For cubic curves, primvar data can be either interpolated cubically between vertices or linearly across segments. The corresponding token for cubic interpolation is 'vertex' and for linear interpolation is 'varying'. Per vertex data should be the same size as the number of vertices in your curve. Segment varying data is dependent on the wrap (periodicity) and number of segments in your curve. For linear curves, varying and vertex data would be interpolated the same way. By convention varying is the preferred interpolation because of the association of varying with linear interpolation.

To convert an entry in the curveVertexCounts vector into a segment count for an individual curve, apply these rules. Sum up all the results in order to compute how many total segments all curves have.

The following tables describe the expected segment count for the 'i'th curve in a curve batch as well as the entire batch. Python syntax like '[:]' (to describe all members of an array) and 'len(...)' (to describe the length of an array) are used.

type wrap curve segment count batch segment count
linear nonperiodic curveVertexCounts[i] - 1 sum(curveVertexCounts[:]) - len(curveVertexCounts)
linear periodic curveVertexCounts[i] sum(curveVertexCounts[:])
cubic nonperiodic (curveVertexCounts[i] - 4) / vstep + 1 sum(curveVertexCounts[:] - 4) / vstep + len(curveVertexCounts)
cubic periodic curveVertexCounts[i] / vstep sum(curveVertexCounts[:]) / vstep
cubic pinned (catmullRom/bspline) (curveVertexCounts[i] - 2) + 1 sum(curveVertexCounts[:] - 2) + len(curveVertexCounts)

The following table descrives the expected size of varying (linearly interpolated) data, derived from the segment counts computed above.

wrap curve varying count batch varying count
nonperiodic/pinned segmentCounts[i] + 1 sum(segmentCounts[:]) + len(curveVertexCounts)
periodic segmentCounts[i] sum(segmentCounts[:])

Both curve types additionally define 'constant' interpolation for the entire prim and 'uniform' interpolation as per curve data.

Note
Take care when providing support for linearly interpolated data for cubic curves. Its shape doesn't provide a one to one mapping with either the number of curves (like 'uniform') or the number of vertices (like 'vertex') and so it is often overlooked. This is the only primitive in UsdGeom (as of this writing) where this is true. For meshes, while they use different interpolation methods, 'varying' and 'vertex' are both specified per point. It's common to assume that curves follow a similar pattern and build in structures and language for per primitive, per element, and per point data only to come upon these arrays that don't quite fit into either of those categories. It is also common to conflate 'varying' with being per segment data and use the segmentCount rules table instead of its neighboring varying data table rules. We suspect that this is because for the common case of nonperiodic cubic curves, both the provided segment count and varying data size formula end with '+ 1'. While debugging, users may look at the double '+ 1' as a mistake and try to remove it. We take this time to enumerate these issues because we've fallen into them before and hope that we save others time in their own implementations.

As an example of deriving per curve segment and varying primvar data counts from the wrap, type, basis, and curveVertexCount, the following table is provided.

wrap type basis curveVertexCount curveSegmentCount varyingDataCount
nonperiodic linear N/A [2 3 2 5] [1 2 1 4] [2 3 2 5]
nonperiodic cubic bezier [4 7 10 4 7] [1 2 3 1 2] [2 3 4 2 3]
nonperiodic cubic bspline [5 4 6 7] [2 1 3 4] [3 2 4 5]
periodic cubic bezier [6 9 6] [2 3 2] [2 3 2]
periodic linear N/A [3 7] [3 7] [3 7]

Tubes and Ribbons

The strictest definition of a curve as an infinitely thin wire is not particularly useful for describing production scenes. The additional widths and normals attributes can be used to describe cylindrical tubes and or flat oriented ribbons.

Curves with only widths defined are imaged as tubes with radius 'width / 2'. Curves with both widths and normals are imaged as ribbons oriented in the direction of the interpolated normal vectors.

While not technically UsdGeomPrimvars, widths and normals also have interpolation metadata. It's common for authored widths to have constant, varying, or vertex interpolation (see UsdGeomCurves::GetWidthsInterpolation()). It's common for authored normals to have varying interpolation (see UsdGeomPointBased::GetNormalsInterpolation()).

The file used to generate these curves can be found in extras/usd/examples/usdGeomExamples/basisCurves.usda. It's provided as a reference on how to properly image both tubes and ribbons. The first row of curves are linear; the second are cubic bezier. (We aim in future releases of HdSt to fix the discontinuity seen with broken tangents to better match offline renderers like RenderMan.) The yellow and violet cubic curves represent cubic vertex width interpolation for which there is no equivalent for linear curves.

Note
How did this prim type get its name? This prim is a portmanteau of two different statements in the original RenderMan specification: 'Basis' and 'Curves'.

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

Definition at line 246 of file basisCurves.h.

Member Typedef Documentation

◆ ComputeInterpolationInfo

typedef std::vector< std::pair<TfToken, size_t> > ComputeInterpolationInfo

Definition at line 435 of file basisCurves.h.

Constructor & Destructor Documentation

◆ UsdGeomBasisCurves() [1/2]

UsdGeomBasisCurves ( const UsdPrim prim = UsdPrim())
inlineexplicit

Construct a UsdGeomBasisCurves on UsdPrim prim .

Equivalent to UsdGeomBasisCurves::Get(prim.GetStage(), prim.GetPath()) for a valid prim, but will not immediately throw an error for an invalid prim

Definition at line 258 of file basisCurves.h.

◆ UsdGeomBasisCurves() [2/2]

UsdGeomBasisCurves ( const UsdSchemaBase schemaObj)
inlineexplicit

Construct a UsdGeomBasisCurves on the prim held by schemaObj .

Should be preferred over UsdGeomBasisCurves(schemaObj.GetPrim()), as it preserves SchemaBase state.

Definition at line 266 of file basisCurves.h.

◆ ~UsdGeomBasisCurves()

virtual USDGEOM_API ~UsdGeomBasisCurves ( )
virtual

Destructor.

Member Function Documentation

◆ _GetSchemaKind()

USDGEOM_API UsdSchemaKind _GetSchemaKind ( ) const
overrideprotectedvirtual

Returns the kind of schema this class belongs to.

See also
UsdSchemaKind

Reimplemented from UsdTyped.

◆ ComputeInterpolationForSize()

USDGEOM_API TfToken ComputeInterpolationForSize ( size_t  n,
const UsdTimeCode timeCode,
ComputeInterpolationInfo *  info = NULL 
) const

Computes interpolation token for n.

If this returns an empty token and info was non-NULL, it'll contain the expected value for each token.

The topology is determined using timeCode.

◆ ComputeSegmentCounts()

USDGEOM_API VtIntArray ComputeSegmentCounts ( const UsdTimeCode timeCode) const

Computes the segment counts of the curves based on their vertex counts from the curveVertexCounts attribute.

◆ ComputeUniformDataSize()

USDGEOM_API size_t ComputeUniformDataSize ( const UsdTimeCode timeCode) const

Computes the expected size for data with "uniform" interpolation.

If you're trying to determine what interpolation to use, it is more efficient to use ComputeInterpolationForSize

◆ ComputeVaryingDataSize()

USDGEOM_API size_t ComputeVaryingDataSize ( const UsdTimeCode timeCode) const

Computes the expected size for data with "varying" interpolation.

If you're trying to determine what interpolation to use, it is more efficient to use ComputeInterpolationForSize

◆ ComputeVertexDataSize()

USDGEOM_API size_t ComputeVertexDataSize ( const UsdTimeCode timeCode) const

Computes the expected size for data with "vertex" interpolation.

If you're trying to determine what interpolation to use, it is more efficient to use ComputeInterpolationForSize

◆ CreateBasisAttr()

USDGEOM_API UsdAttribute CreateBasisAttr ( VtValue const &  defaultValue = VtValue(),
bool  writeSparsely = false 
) const

See GetBasisAttr(), 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.

◆ CreateTypeAttr()

USDGEOM_API UsdAttribute CreateTypeAttr ( VtValue const &  defaultValue = VtValue(),
bool  writeSparsely = false 
) const

See GetTypeAttr(), 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.

◆ CreateWrapAttr()

USDGEOM_API UsdAttribute CreateWrapAttr ( VtValue const &  defaultValue = VtValue(),
bool  writeSparsely = false 
) const

See GetWrapAttr(), 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.

◆ Define()

static USDGEOM_API UsdGeomBasisCurves Define ( const UsdStagePtr &  stage,
const SdfPath path 
)
static

Attempt to ensure a UsdPrim adhering to this schema at path is defined (according to UsdPrim::IsDefined()) on this stage.

If a prim adhering to this schema at path is already defined on this stage, return that prim. Otherwise author an SdfPrimSpec with specifier == SdfSpecifierDef and this schema's prim type name for the prim at path at the current EditTarget. Author SdfPrimSpec s with specifier == SdfSpecifierDef and empty typeName at the current EditTarget for any nonexistent, or existing but not Defined ancestors.

The given path must be an absolute prim path that does not contain any variant selections.

If it is impossible to author any of the necessary PrimSpecs, (for example, in case path cannot map to the current UsdEditTarget's namespace) issue an error and return an invalid UsdPrim.

Note that this method may return a defined prim whose typeName does not specify this schema class, in case a stronger typeName opinion overrides the opinion at the current EditTarget.

◆ Get()

static USDGEOM_API UsdGeomBasisCurves Get ( const UsdStagePtr &  stage,
const SdfPath path 
)
static

Return a UsdGeomBasisCurves holding the prim adhering to this schema at path on stage.

If no prim exists at path on stage, or if the prim at that path does not adhere to this schema, return an invalid schema object. This is shorthand for the following:

UsdGeomBasisCurves(stage->GetPrimAtPath(path));
BasisCurves are a batched curve representation analogous to the classic RIB definition via Basis and ...
Definition: basisCurves.h:247

◆ GetBasisAttr()

USDGEOM_API UsdAttribute GetBasisAttr ( ) const

The basis specifies the vstep and matrix used for cubic interpolation.

Note
The 'hermite' and 'power' tokens have been removed. We've provided UsdGeomHermiteCurves as an alternative for the 'hermite' basis.
Declaration uniform token basis = "bezier"
C++ Type TfToken
Usd Type SdfValueTypeNames->Token
Variability SdfVariabilityUniform
Allowed Values bezier, bspline, catmullRom

◆ GetSchemaAttributeNames()

static USDGEOM_API const TfTokenVector & GetSchemaAttributeNames ( bool  includeInherited = true)
static

Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.

Does not include attributes that may be authored by custom/extended methods of the schemas involved.

◆ GetTypeAttr()

USDGEOM_API UsdAttribute GetTypeAttr ( ) const

Linear curves interpolate linearly between two vertices.


Cubic curves use a basis matrix with four vertices to interpolate a segment.

Declaration uniform token type = "cubic"
C++ Type TfToken
Usd Type SdfValueTypeNames->Token
Variability SdfVariabilityUniform
Allowed Values linear, cubic

◆ GetWrapAttr()

USDGEOM_API UsdAttribute GetWrapAttr ( ) const

If wrap is set to periodic, the curve when rendered will repeat the initial vertices (dependent on the vstep) to close the curve.

If wrap is set to 'pinned', phantom points may be created to ensure that the curve interpolation starts at P[0] and ends at P[n-1].

Declaration uniform token wrap = "nonperiodic"
C++ Type TfToken
Usd Type SdfValueTypeNames->Token
Variability SdfVariabilityUniform
Allowed Values nonperiodic, periodic, pinned

Friends And Related Function Documentation

◆ UsdSchemaRegistry

friend class UsdSchemaRegistry
friend

Definition at line 330 of file basisCurves.h.

Member Data Documentation

◆ schemaKind

const UsdSchemaKind schemaKind = UsdSchemaKind::ConcreteTyped
static

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

See also
UsdSchemaKind

Definition at line 252 of file basisCurves.h.


The documentation for this class was generated from the following file: