UsdPhysics module — pxr-usd-api 105.1 documentation pxr-usd-api » Modules » UsdPhysics module   # UsdPhysics module Summary: The UsdPhysics module defines the physics-related prim and property schemas that together form a physics simulation representation. Classes: ArticulationRootAPI PhysicsArticulationRootAPI can be applied to a scene graph node, and marks the subtree rooted here for inclusion in one or more reduced coordinate articulations. CollisionAPI Applies collision attributes to a UsdGeomXformable prim. CollisionGroup Defines a collision group for coarse filtering. CollisionGroupTable DistanceJoint Predefined distance joint type (Distance between rigid bodies may be limited to given minimum or maximum distance.) DriveAPI The PhysicsDriveAPI when applied to any joint primitive will drive the joint towards a given target. FilteredPairsAPI API to describe fine-grained filtering. FixedJoint Predefined fixed joint type (All degrees of freedom are removed.) Joint A joint constrains the movement of rigid bodies. LimitAPI The PhysicsLimitAPI can be applied to a PhysicsJoint and will restrict the movement along an axis. MassAPI Defines explicit mass properties (mass, density, inertia etc.). MassUnits Container class for static double-precision symbols representing common mass units of measure expressed in kilograms. MaterialAPI Adds simulation material properties to a Material. MeshCollisionAPI Attributes to control how a Mesh is made into a collider. PrismaticJoint Predefined prismatic joint type (translation along prismatic joint axis is permitted.) RevoluteJoint Predefined revolute joint type (rotation along revolute joint axis is permitted.) RigidBodyAPI Applies physics body attributes to any UsdGeomXformable prim and marks that prim to be driven by a simulation. Scene General physics simulation properties, required for simulation. SphericalJoint Predefined spherical joint type (Removes linear degrees of freedom, cone limit may restrict the motion in a given range.) It allows two limit values, which when equal create a circular, else an elliptic cone limit around the limit axis. Tokens class pxr.UsdPhysics.ArticulationRootAPI PhysicsArticulationRootAPI can be applied to a scene graph node, and marks the subtree rooted here for inclusion in one or more reduced coordinate articulations. For floating articulations, this should be on the root body. For fixed articulations (robotics jargon for e.g. a robot arm for welding that is bolted to the floor), this API can be on a direct or indirect parent of the root joint which is connected to the world, or on the joint itself.. Methods: Apply classmethod Apply(prim) -> ArticulationRootAPI CanApply classmethod CanApply(prim, whyNot) -> bool Get classmethod Get(stage, path) -> ArticulationRootAPI GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] static Apply() classmethod Apply(prim) -> ArticulationRootAPI Applies this single-apply API schema to the given prim . This information is stored by adding”PhysicsArticulationRootAPI”to the token-valued, listOp metadata apiSchemas on the prim. A valid UsdPhysicsArticulationRootAPI object is returned upon success. An invalid (or empty) UsdPhysicsArticulationRootAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – static CanApply() classmethod CanApply(prim, whyNot) -> bool Returns true if this single-apply API schema can be applied to the given prim . If this schema can not be a applied to the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – whyNot (str) – static Get() classmethod Get(stage, path) -> ArticulationRootAPI Return a UsdPhysicsArticulationRootAPI 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: UsdPhysicsArticulationRootAPI(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.CollisionAPI Applies collision attributes to a UsdGeomXformable prim. If a simulation is running, this geometry will collide with other geometries that have PhysicsCollisionAPI applied. If a prim in the parent hierarchy has the RigidBodyAPI applied, this collider is a part of that body. If there is no body in the parent hierarchy, this collider is considered to be static. Methods: Apply classmethod Apply(prim) -> CollisionAPI CanApply classmethod CanApply(prim, whyNot) -> bool CreateCollisionEnabledAttr(defaultValue, ...) See GetCollisionEnabledAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateSimulationOwnerRel() See GetSimulationOwnerRel() , and also Create vs Get Property Methods for when to use Get vs Create. Get classmethod Get(stage, path) -> CollisionAPI GetCollisionEnabledAttr() Determines if the PhysicsCollisionAPI is enabled. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] GetSimulationOwnerRel() Single PhysicsScene that will simulate this collider. static Apply() classmethod Apply(prim) -> CollisionAPI Applies this single-apply API schema to the given prim . This information is stored by adding”PhysicsCollisionAPI”to the token- valued, listOp metadata apiSchemas on the prim. A valid UsdPhysicsCollisionAPI object is returned upon success. An invalid (or empty) UsdPhysicsCollisionAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – static CanApply() classmethod CanApply(prim, whyNot) -> bool Returns true if this single-apply API schema can be applied to the given prim . If this schema can not be a applied to the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – whyNot (str) – CreateCollisionEnabledAttr(defaultValue, writeSparsely) → Attribute See GetCollisionEnabledAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateSimulationOwnerRel() → Relationship See GetSimulationOwnerRel() , and also Create vs Get Property Methods for when to use Get vs Create. static Get() classmethod Get(stage, path) -> CollisionAPI Return a UsdPhysicsCollisionAPI 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: UsdPhysicsCollisionAPI(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetCollisionEnabledAttr() → Attribute Determines if the PhysicsCollisionAPI is enabled. Declaration bool physics:collisionEnabled = 1 C++ Type bool Usd Type SdfValueTypeNames->Bool static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – GetSimulationOwnerRel() → Relationship Single PhysicsScene that will simulate this collider. By default this object belongs to the first PhysicsScene. Note that if a RigidBodyAPI in the hierarchy above has a different simulationOwner then it has a precedence over this relationship. class pxr.UsdPhysics.CollisionGroup Defines a collision group for coarse filtering. When a collision occurs between two objects that have a PhysicsCollisionGroup assigned, they will collide with each other unless this PhysicsCollisionGroup pair is filtered. See filteredGroups attribute. A CollectionAPI:colliders maintains a list of PhysicsCollisionAPI rel-s that defines the members of this Collisiongroup. Methods: ComputeCollisionGroupTable classmethod ComputeCollisionGroupTable(stage) -> CollisionGroupTable CreateFilteredGroupsRel() See GetFilteredGroupsRel() , and also Create vs Get Property Methods for when to use Get vs Create. CreateInvertFilteredGroupsAttr(defaultValue, ...) See GetInvertFilteredGroupsAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateMergeGroupNameAttr(defaultValue, ...) See GetMergeGroupNameAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Define classmethod Define(stage, path) -> CollisionGroup Get classmethod Get(stage, path) -> CollisionGroup GetCollidersCollectionAPI() Return the UsdCollectionAPI interface used for defining what colliders belong to the CollisionGroup. GetFilteredGroupsRel() References a list of PhysicsCollisionGroups with which collisions should be ignored. GetInvertFilteredGroupsAttr() Normally, the filter will disable collisions against the selected filter groups. GetMergeGroupNameAttr() If non-empty, any collision groups in a stage with a matching mergeGroup should be considered to refer to the same collection. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] static ComputeCollisionGroupTable() classmethod ComputeCollisionGroupTable(stage) -> CollisionGroupTable Compute a table encoding all the collision groups filter rules for a stage. This can be used as a reference to validate an implementation of the collision groups filters. The returned table is diagonally symmetric. Parameters stage (Stage) – CreateFilteredGroupsRel() → Relationship See GetFilteredGroupsRel() , and also Create vs Get Property Methods for when to use Get vs Create. CreateInvertFilteredGroupsAttr(defaultValue, writeSparsely) → Attribute See GetInvertFilteredGroupsAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateMergeGroupNameAttr(defaultValue, writeSparsely) → Attribute See GetMergeGroupNameAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Define() classmethod Define(stage, path) -> CollisionGroup 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. Parameters stage (Stage) – path (Path) – static Get() classmethod Get(stage, path) -> CollisionGroup Return a UsdPhysicsCollisionGroup 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: UsdPhysicsCollisionGroup(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetCollidersCollectionAPI() → CollectionAPI Return the UsdCollectionAPI interface used for defining what colliders belong to the CollisionGroup. GetFilteredGroupsRel() → Relationship References a list of PhysicsCollisionGroups with which collisions should be ignored. GetInvertFilteredGroupsAttr() → Attribute Normally, the filter will disable collisions against the selected filter groups. However, if this option is set, the filter will disable collisions against all colliders except for those in the selected filter groups. Declaration bool physics:invertFilteredGroups C++ Type bool Usd Type SdfValueTypeNames->Bool GetMergeGroupNameAttr() → Attribute If non-empty, any collision groups in a stage with a matching mergeGroup should be considered to refer to the same collection. Matching collision groups should behave as if there were a single group containing referenced colliders and filter groups from both collections. Declaration string physics:mergeGroup C++ Type std::string Usd Type SdfValueTypeNames->String static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.CollisionGroupTable Methods: GetGroups IsCollisionEnabled GetGroups() IsCollisionEnabled() class pxr.UsdPhysics.DistanceJoint Predefined distance joint type (Distance between rigid bodies may be limited to given minimum or maximum distance.) Methods: CreateMaxDistanceAttr(defaultValue, ...) See GetMaxDistanceAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateMinDistanceAttr(defaultValue, ...) See GetMinDistanceAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Define classmethod Define(stage, path) -> DistanceJoint Get classmethod Get(stage, path) -> DistanceJoint GetMaxDistanceAttr() Maximum distance. GetMinDistanceAttr() Minimum distance. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] CreateMaxDistanceAttr(defaultValue, writeSparsely) → Attribute See GetMaxDistanceAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateMinDistanceAttr(defaultValue, writeSparsely) → Attribute See GetMinDistanceAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Define() classmethod Define(stage, path) -> DistanceJoint 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. Parameters stage (Stage) – path (Path) – static Get() classmethod Get(stage, path) -> DistanceJoint Return a UsdPhysicsDistanceJoint 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: UsdPhysicsDistanceJoint(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetMaxDistanceAttr() → Attribute Maximum distance. If attribute is negative, the joint is not limited. Units: distance. Declaration float physics:maxDistance = -1 C++ Type float Usd Type SdfValueTypeNames->Float GetMinDistanceAttr() → Attribute Minimum distance. If attribute is negative, the joint is not limited. Units: distance. Declaration float physics:minDistance = -1 C++ Type float Usd Type SdfValueTypeNames->Float static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.DriveAPI The PhysicsDriveAPI when applied to any joint primitive will drive the joint towards a given target. The PhysicsDriveAPI is a multipleApply schema: drive can be set per axis”transX”,”transY”,”transZ”,”rotX”,”rotY”,”rotZ”or its”linear”for prismatic joint or”angular”for revolute joints. Setting these as a multipleApply schema TfToken name will define the degree of freedom the DriveAPI is applied to. Each drive is an implicit force-limited damped spring: Force or acceleration = stiffness * (targetPosition - position) damping * (targetVelocity - velocity) For any described attribute Fallback Value or Allowed Values below that are text/tokens, the actual token is published and defined in UsdPhysicsTokens. So to set an attribute to the value”rightHanded”, use UsdPhysicsTokens->rightHanded as the value. Methods: Apply classmethod Apply(prim, name) -> DriveAPI CanApply classmethod CanApply(prim, name, whyNot) -> bool CreateDampingAttr(defaultValue, writeSparsely) See GetDampingAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateMaxForceAttr(defaultValue, writeSparsely) See GetMaxForceAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateStiffnessAttr(defaultValue, writeSparsely) See GetStiffnessAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateTargetPositionAttr(defaultValue, ...) See GetTargetPositionAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateTargetVelocityAttr(defaultValue, ...) See GetTargetVelocityAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateTypeAttr(defaultValue, writeSparsely) See GetTypeAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Get classmethod Get(stage, path) -> DriveAPI GetAll classmethod GetAll(prim) -> list[DriveAPI] GetDampingAttr() Damping of the drive. GetMaxForceAttr() Maximum force that can be applied to drive. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] GetStiffnessAttr() Stiffness of the drive. GetTargetPositionAttr() Target value for position. GetTargetVelocityAttr() Target value for velocity. GetTypeAttr() Drive spring is for the acceleration at the joint (rather than the force). IsPhysicsDriveAPIPath classmethod IsPhysicsDriveAPIPath(path, name) -> bool static Apply() classmethod Apply(prim, name) -> DriveAPI Applies this multiple-apply API schema to the given prim along with the given instance name, name . This information is stored by adding”PhysicsDriveAPI:name”to the token-valued, listOp metadata apiSchemas on the prim. For example, if name is’instance1’, the token’PhysicsDriveAPI:instance1’is added to’apiSchemas’. A valid UsdPhysicsDriveAPI object is returned upon success. An invalid (or empty) UsdPhysicsDriveAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – name (str) – static CanApply() classmethod CanApply(prim, name, whyNot) -> bool Returns true if this multiple-apply API schema can be applied, with the given instance name, name , to the given prim . If this schema can not be a applied the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – name (str) – whyNot (str) – CreateDampingAttr(defaultValue, writeSparsely) → Attribute See GetDampingAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateMaxForceAttr(defaultValue, writeSparsely) → Attribute See GetMaxForceAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateStiffnessAttr(defaultValue, writeSparsely) → Attribute See GetStiffnessAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateTargetPositionAttr(defaultValue, writeSparsely) → Attribute See GetTargetPositionAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateTargetVelocityAttr(defaultValue, writeSparsely) → Attribute See GetTargetVelocityAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateTypeAttr(defaultValue, writeSparsely) → Attribute 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Get() classmethod Get(stage, path) -> DriveAPI Return a UsdPhysicsDriveAPI 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. path must be of the format.drive:name. This is shorthand for the following: TfToken name = SdfPath::StripNamespace(path.GetToken()); UsdPhysicsDriveAPI( stage->GetPrimAtPath(path.GetPrimPath()), name); Parameters stage (Stage) – path (Path) – Get(prim, name) -> DriveAPI Return a UsdPhysicsDriveAPI with name name holding the prim prim . Shorthand for UsdPhysicsDriveAPI(prim, name); Parameters prim (Prim) – name (str) – static GetAll() classmethod GetAll(prim) -> list[DriveAPI] Return a vector of all named instances of UsdPhysicsDriveAPI on the given prim . Parameters prim (Prim) – GetDampingAttr() → Attribute Damping of the drive. Units: if linear drive: mass/second If angular drive: mass*DIST_UNITS*DIST_UNITS/second/second/degrees. Declaration float physics:damping = 0 C++ Type float Usd Type SdfValueTypeNames->Float GetMaxForceAttr() → Attribute Maximum force that can be applied to drive. Units: if linear drive: mass*DIST_UNITS/second/second if angular drive: mass*DIST_UNITS*DIST_UNITS/second/second inf means not limited. Must be non-negative. Declaration float physics:maxForce = inf C++ Type float Usd Type SdfValueTypeNames->Float static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – GetSchemaAttributeNames(includeInherited, instanceName) -> list[TfToken] Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes for a given instance name. Does not include attributes that may be authored by custom/extended methods of the schemas involved. The names returned will have the proper namespace prefix. Parameters includeInherited (bool) – instanceName (str) – GetStiffnessAttr() → Attribute Stiffness of the drive. Units: if linear drive: mass/second/second if angular drive: mass*DIST_UNITS*DIST_UNITS/degree/second/second. Declaration float physics:stiffness = 0 C++ Type float Usd Type SdfValueTypeNames->Float GetTargetPositionAttr() → Attribute Target value for position. Units: if linear drive: distance if angular drive: degrees. Declaration float physics:targetPosition = 0 C++ Type float Usd Type SdfValueTypeNames->Float GetTargetVelocityAttr() → Attribute Target value for velocity. Units: if linear drive: distance/second if angular drive: degrees/second. Declaration float physics:targetVelocity = 0 C++ Type float Usd Type SdfValueTypeNames->Float GetTypeAttr() → Attribute Drive spring is for the acceleration at the joint (rather than the force). Declaration uniform token physics:type ="force" C++ Type TfToken Usd Type SdfValueTypeNames->Token Variability SdfVariabilityUniform Allowed Values force, acceleration static IsPhysicsDriveAPIPath() classmethod IsPhysicsDriveAPIPath(path, name) -> bool Checks if the given path path is of an API schema of type PhysicsDriveAPI. If so, it stores the instance name of the schema in name and returns true. Otherwise, it returns false. Parameters path (Path) – name (str) – class pxr.UsdPhysics.FilteredPairsAPI API to describe fine-grained filtering. If a collision between two objects occurs, this pair might be filtered if the pair is defined through this API. This API can be applied either to a body or collision or even articulation. The”filteredPairs”defines what objects it should not collide against. Note that FilteredPairsAPI filtering has precedence over CollisionGroup filtering. Methods: Apply classmethod Apply(prim) -> FilteredPairsAPI CanApply classmethod CanApply(prim, whyNot) -> bool CreateFilteredPairsRel() See GetFilteredPairsRel() , and also Create vs Get Property Methods for when to use Get vs Create. Get classmethod Get(stage, path) -> FilteredPairsAPI GetFilteredPairsRel() Relationship to objects that should be filtered. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] static Apply() classmethod Apply(prim) -> FilteredPairsAPI Applies this single-apply API schema to the given prim . This information is stored by adding”PhysicsFilteredPairsAPI”to the token-valued, listOp metadata apiSchemas on the prim. A valid UsdPhysicsFilteredPairsAPI object is returned upon success. An invalid (or empty) UsdPhysicsFilteredPairsAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – static CanApply() classmethod CanApply(prim, whyNot) -> bool Returns true if this single-apply API schema can be applied to the given prim . If this schema can not be a applied to the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – whyNot (str) – CreateFilteredPairsRel() → Relationship See GetFilteredPairsRel() , and also Create vs Get Property Methods for when to use Get vs Create. static Get() classmethod Get(stage, path) -> FilteredPairsAPI Return a UsdPhysicsFilteredPairsAPI 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: UsdPhysicsFilteredPairsAPI(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetFilteredPairsRel() → Relationship Relationship to objects that should be filtered. static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.FixedJoint Predefined fixed joint type (All degrees of freedom are removed.) Methods: Define classmethod Define(stage, path) -> FixedJoint Get classmethod Get(stage, path) -> FixedJoint GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] static Define() classmethod Define(stage, path) -> FixedJoint 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. Parameters stage (Stage) – path (Path) – static Get() classmethod Get(stage, path) -> FixedJoint Return a UsdPhysicsFixedJoint 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: UsdPhysicsFixedJoint(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.Joint A joint constrains the movement of rigid bodies. Joint can be created between two rigid bodies or between one rigid body and world. By default joint primitive defines a D6 joint where all degrees of freedom are free. Three linear and three angular degrees of freedom. Note that default behavior is to disable collision between jointed bodies. Methods: CreateBody0Rel() See GetBody0Rel() , and also Create vs Get Property Methods for when to use Get vs Create. CreateBody1Rel() See GetBody1Rel() , and also Create vs Get Property Methods for when to use Get vs Create. CreateBreakForceAttr(defaultValue, writeSparsely) See GetBreakForceAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateBreakTorqueAttr(defaultValue, ...) See GetBreakTorqueAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateCollisionEnabledAttr(defaultValue, ...) See GetCollisionEnabledAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateExcludeFromArticulationAttr(...) See GetExcludeFromArticulationAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateJointEnabledAttr(defaultValue, ...) See GetJointEnabledAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateLocalPos0Attr(defaultValue, writeSparsely) See GetLocalPos0Attr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateLocalPos1Attr(defaultValue, writeSparsely) See GetLocalPos1Attr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateLocalRot0Attr(defaultValue, writeSparsely) See GetLocalRot0Attr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateLocalRot1Attr(defaultValue, writeSparsely) See GetLocalRot1Attr() , and also Create vs Get Property Methods for when to use Get vs Create. Define classmethod Define(stage, path) -> Joint Get classmethod Get(stage, path) -> Joint GetBody0Rel() Relationship to any UsdGeomXformable. GetBody1Rel() Relationship to any UsdGeomXformable. GetBreakForceAttr() Joint break force. GetBreakTorqueAttr() Joint break torque. GetCollisionEnabledAttr() Determines if the jointed subtrees should collide or not. GetExcludeFromArticulationAttr() Determines if the joint can be included in an Articulation. GetJointEnabledAttr() Determines if the joint is enabled. GetLocalPos0Attr() Relative position of the joint frame to body0's frame. GetLocalPos1Attr() Relative position of the joint frame to body1's frame. GetLocalRot0Attr() Relative orientation of the joint frame to body0's frame. GetLocalRot1Attr() Relative orientation of the joint frame to body1's frame. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] CreateBody0Rel() → Relationship See GetBody0Rel() , and also Create vs Get Property Methods for when to use Get vs Create. CreateBody1Rel() → Relationship See GetBody1Rel() , and also Create vs Get Property Methods for when to use Get vs Create. CreateBreakForceAttr(defaultValue, writeSparsely) → Attribute See GetBreakForceAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateBreakTorqueAttr(defaultValue, writeSparsely) → Attribute See GetBreakTorqueAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateCollisionEnabledAttr(defaultValue, writeSparsely) → Attribute See GetCollisionEnabledAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateExcludeFromArticulationAttr(defaultValue, writeSparsely) → Attribute See GetExcludeFromArticulationAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateJointEnabledAttr(defaultValue, writeSparsely) → Attribute See GetJointEnabledAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateLocalPos0Attr(defaultValue, writeSparsely) → Attribute See GetLocalPos0Attr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateLocalPos1Attr(defaultValue, writeSparsely) → Attribute See GetLocalPos1Attr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateLocalRot0Attr(defaultValue, writeSparsely) → Attribute See GetLocalRot0Attr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateLocalRot1Attr(defaultValue, writeSparsely) → Attribute See GetLocalRot1Attr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Define() classmethod Define(stage, path) -> Joint 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. Parameters stage (Stage) – path (Path) – static Get() classmethod Get(stage, path) -> Joint Return a UsdPhysicsJoint 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: UsdPhysicsJoint(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetBody0Rel() → Relationship Relationship to any UsdGeomXformable. GetBody1Rel() → Relationship Relationship to any UsdGeomXformable. GetBreakForceAttr() → Attribute Joint break force. If set, joint is to break when this force limit is reached. (Used for linear DOFs.) Units: mass * distance / second / second Declaration float physics:breakForce = inf C++ Type float Usd Type SdfValueTypeNames->Float GetBreakTorqueAttr() → Attribute Joint break torque. If set, joint is to break when this torque limit is reached. (Used for angular DOFs.) Units: mass * distance * distance / second / second Declaration float physics:breakTorque = inf C++ Type float Usd Type SdfValueTypeNames->Float GetCollisionEnabledAttr() → Attribute Determines if the jointed subtrees should collide or not. Declaration bool physics:collisionEnabled = 0 C++ Type bool Usd Type SdfValueTypeNames->Bool GetExcludeFromArticulationAttr() → Attribute Determines if the joint can be included in an Articulation. Declaration uniform bool physics:excludeFromArticulation = 0 C++ Type bool Usd Type SdfValueTypeNames->Bool Variability SdfVariabilityUniform GetJointEnabledAttr() → Attribute Determines if the joint is enabled. Declaration bool physics:jointEnabled = 1 C++ Type bool Usd Type SdfValueTypeNames->Bool GetLocalPos0Attr() → Attribute Relative position of the joint frame to body0’s frame. Declaration point3f physics:localPos0 = (0, 0, 0) C++ Type GfVec3f Usd Type SdfValueTypeNames->Point3f GetLocalPos1Attr() → Attribute Relative position of the joint frame to body1’s frame. Declaration point3f physics:localPos1 = (0, 0, 0) C++ Type GfVec3f Usd Type SdfValueTypeNames->Point3f GetLocalRot0Attr() → Attribute Relative orientation of the joint frame to body0’s frame. Declaration quatf physics:localRot0 = (1, 0, 0, 0) C++ Type GfQuatf Usd Type SdfValueTypeNames->Quatf GetLocalRot1Attr() → Attribute Relative orientation of the joint frame to body1’s frame. Declaration quatf physics:localRot1 = (1, 0, 0, 0) C++ Type GfQuatf Usd Type SdfValueTypeNames->Quatf static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.LimitAPI The PhysicsLimitAPI can be applied to a PhysicsJoint and will restrict the movement along an axis. PhysicsLimitAPI is a multipleApply schema: The PhysicsJoint can be restricted along”transX”,”transY”,”transZ”,”rotX”,”rotY”,”rotZ”,”distance”. Setting these as a multipleApply schema TfToken name will define the degree of freedom the PhysicsLimitAPI is applied to. Note that if the low limit is higher than the high limit, motion along this axis is considered locked. Methods: Apply classmethod Apply(prim, name) -> LimitAPI CanApply classmethod CanApply(prim, name, whyNot) -> bool CreateHighAttr(defaultValue, writeSparsely) See GetHighAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateLowAttr(defaultValue, writeSparsely) See GetLowAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Get classmethod Get(stage, path) -> LimitAPI GetAll classmethod GetAll(prim) -> list[LimitAPI] GetHighAttr() Upper limit. GetLowAttr() Lower limit. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] IsPhysicsLimitAPIPath classmethod IsPhysicsLimitAPIPath(path, name) -> bool static Apply() classmethod Apply(prim, name) -> LimitAPI Applies this multiple-apply API schema to the given prim along with the given instance name, name . This information is stored by adding”PhysicsLimitAPI:name”to the token-valued, listOp metadata apiSchemas on the prim. For example, if name is’instance1’, the token’PhysicsLimitAPI:instance1’is added to’apiSchemas’. A valid UsdPhysicsLimitAPI object is returned upon success. An invalid (or empty) UsdPhysicsLimitAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – name (str) – static CanApply() classmethod CanApply(prim, name, whyNot) -> bool Returns true if this multiple-apply API schema can be applied, with the given instance name, name , to the given prim . If this schema can not be a applied the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – name (str) – whyNot (str) – CreateHighAttr(defaultValue, writeSparsely) → Attribute See GetHighAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateLowAttr(defaultValue, writeSparsely) → Attribute See GetLowAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Get() classmethod Get(stage, path) -> LimitAPI Return a UsdPhysicsLimitAPI 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. path must be of the format.limit:name. This is shorthand for the following: TfToken name = SdfPath::StripNamespace(path.GetToken()); UsdPhysicsLimitAPI( stage->GetPrimAtPath(path.GetPrimPath()), name); Parameters stage (Stage) – path (Path) – Get(prim, name) -> LimitAPI Return a UsdPhysicsLimitAPI with name name holding the prim prim . Shorthand for UsdPhysicsLimitAPI(prim, name); Parameters prim (Prim) – name (str) – static GetAll() classmethod GetAll(prim) -> list[LimitAPI] Return a vector of all named instances of UsdPhysicsLimitAPI on the given prim . Parameters prim (Prim) – GetHighAttr() → Attribute Upper limit. Units: degrees or distance depending on trans or rot axis applied to. inf means not limited in positive direction. Declaration float physics:high = inf C++ Type float Usd Type SdfValueTypeNames->Float GetLowAttr() → Attribute Lower limit. Units: degrees or distance depending on trans or rot axis applied to. -inf means not limited in negative direction. Declaration float physics:low = -inf C++ Type float Usd Type SdfValueTypeNames->Float static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – GetSchemaAttributeNames(includeInherited, instanceName) -> list[TfToken] Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes for a given instance name. Does not include attributes that may be authored by custom/extended methods of the schemas involved. The names returned will have the proper namespace prefix. Parameters includeInherited (bool) – instanceName (str) – static IsPhysicsLimitAPIPath() classmethod IsPhysicsLimitAPIPath(path, name) -> bool Checks if the given path path is of an API schema of type PhysicsLimitAPI. If so, it stores the instance name of the schema in name and returns true. Otherwise, it returns false. Parameters path (Path) – name (str) – class pxr.UsdPhysics.MassAPI Defines explicit mass properties (mass, density, inertia etc.). MassAPI can be applied to any object that has a PhysicsCollisionAPI or a PhysicsRigidBodyAPI. Methods: Apply classmethod Apply(prim) -> MassAPI CanApply classmethod CanApply(prim, whyNot) -> bool CreateCenterOfMassAttr(defaultValue, ...) See GetCenterOfMassAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateDensityAttr(defaultValue, writeSparsely) See GetDensityAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateDiagonalInertiaAttr(defaultValue, ...) See GetDiagonalInertiaAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateMassAttr(defaultValue, writeSparsely) See GetMassAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreatePrincipalAxesAttr(defaultValue, ...) See GetPrincipalAxesAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Get classmethod Get(stage, path) -> MassAPI GetCenterOfMassAttr() Center of mass in the prim's local space. GetDensityAttr() If non-zero, specifies the density of the object. GetDiagonalInertiaAttr() If non-zero, specifies diagonalized inertia tensor along the principal axes. GetMassAttr() If non-zero, directly specifies the mass of the object. GetPrincipalAxesAttr() Orientation of the inertia tensor's principal axes in the prim's local space. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] static Apply() classmethod Apply(prim) -> MassAPI Applies this single-apply API schema to the given prim . This information is stored by adding”PhysicsMassAPI”to the token- valued, listOp metadata apiSchemas on the prim. A valid UsdPhysicsMassAPI object is returned upon success. An invalid (or empty) UsdPhysicsMassAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – static CanApply() classmethod CanApply(prim, whyNot) -> bool Returns true if this single-apply API schema can be applied to the given prim . If this schema can not be a applied to the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – whyNot (str) – CreateCenterOfMassAttr(defaultValue, writeSparsely) → Attribute See GetCenterOfMassAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateDensityAttr(defaultValue, writeSparsely) → Attribute See GetDensityAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateDiagonalInertiaAttr(defaultValue, writeSparsely) → Attribute See GetDiagonalInertiaAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateMassAttr(defaultValue, writeSparsely) → Attribute See GetMassAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreatePrincipalAxesAttr(defaultValue, writeSparsely) → Attribute See GetPrincipalAxesAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Get() classmethod Get(stage, path) -> MassAPI Return a UsdPhysicsMassAPI 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: UsdPhysicsMassAPI(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetCenterOfMassAttr() → Attribute Center of mass in the prim’s local space. Units: distance. Declaration point3f physics:centerOfMass = (-inf, -inf, -inf) C++ Type GfVec3f Usd Type SdfValueTypeNames->Point3f GetDensityAttr() → Attribute If non-zero, specifies the density of the object. In the context of rigid body physics, density indirectly results in setting mass via (mass = density x volume of the object). How the volume is computed is up to implementation of the physics system. It is generally computed from the collision approximation rather than the graphical mesh. In the case where both density and mass are specified for the same object, mass has precedence over density. Unlike mass, child’s prim’s density overrides parent prim’s density as it is accumulative. Note that density of a collisionAPI can be also alternatively set through a PhysicsMaterialAPI. The material density has the weakest precedence in density definition. Note if density is 0.0 it is ignored. Units: mass/distance/distance/distance. Declaration float physics:density = 0 C++ Type float Usd Type SdfValueTypeNames->Float GetDiagonalInertiaAttr() → Attribute If non-zero, specifies diagonalized inertia tensor along the principal axes. Note if diagonalInertial is (0.0, 0.0, 0.0) it is ignored. Units: mass*distance*distance. Declaration float3 physics:diagonalInertia = (0, 0, 0) C++ Type GfVec3f Usd Type SdfValueTypeNames->Float3 GetMassAttr() → Attribute If non-zero, directly specifies the mass of the object. Note that any child prim can also have a mass when they apply massAPI. In this case, the precedence rule is’parent mass overrides the child’s’. This may come as counter-intuitive, but mass is a computed quantity and in general not accumulative. For example, if a parent has mass of 10, and one of two children has mass of 20, allowing child’s mass to override its parent results in a mass of -10 for the other child. Note if mass is 0.0 it is ignored. Units: mass. Declaration float physics:mass = 0 C++ Type float Usd Type SdfValueTypeNames->Float GetPrincipalAxesAttr() → Attribute Orientation of the inertia tensor’s principal axes in the prim’s local space. Declaration quatf physics:principalAxes = (0, 0, 0, 0) C++ Type GfQuatf Usd Type SdfValueTypeNames->Quatf static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.MassUnits Container class for static double-precision symbols representing common mass units of measure expressed in kilograms. Attributes: grams kilograms slugs grams = 0.001 kilograms = 1.0 slugs = 14.5939 class pxr.UsdPhysics.MaterialAPI Adds simulation material properties to a Material. All collisions that have a relationship to this material will have their collision response defined through this material. Methods: Apply classmethod Apply(prim) -> MaterialAPI CanApply classmethod CanApply(prim, whyNot) -> bool CreateDensityAttr(defaultValue, writeSparsely) See GetDensityAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateDynamicFrictionAttr(defaultValue, ...) See GetDynamicFrictionAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateRestitutionAttr(defaultValue, ...) See GetRestitutionAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateStaticFrictionAttr(defaultValue, ...) See GetStaticFrictionAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Get classmethod Get(stage, path) -> MaterialAPI GetDensityAttr() If non-zero, defines the density of the material. GetDynamicFrictionAttr() Dynamic friction coefficient. GetRestitutionAttr() Restitution coefficient. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] GetStaticFrictionAttr() Static friction coefficient. static Apply() classmethod Apply(prim) -> MaterialAPI Applies this single-apply API schema to the given prim . This information is stored by adding”PhysicsMaterialAPI”to the token- valued, listOp metadata apiSchemas on the prim. A valid UsdPhysicsMaterialAPI object is returned upon success. An invalid (or empty) UsdPhysicsMaterialAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – static CanApply() classmethod CanApply(prim, whyNot) -> bool Returns true if this single-apply API schema can be applied to the given prim . If this schema can not be a applied to the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – whyNot (str) – CreateDensityAttr(defaultValue, writeSparsely) → Attribute See GetDensityAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateDynamicFrictionAttr(defaultValue, writeSparsely) → Attribute See GetDynamicFrictionAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateRestitutionAttr(defaultValue, writeSparsely) → Attribute See GetRestitutionAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateStaticFrictionAttr(defaultValue, writeSparsely) → Attribute See GetStaticFrictionAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Get() classmethod Get(stage, path) -> MaterialAPI Return a UsdPhysicsMaterialAPI 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: UsdPhysicsMaterialAPI(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetDensityAttr() → Attribute If non-zero, defines the density of the material. This can be used for body mass computation, see PhysicsMassAPI. Note that if the density is 0.0 it is ignored. Units: mass/distance/distance/distance. Declaration float physics:density = 0 C++ Type float Usd Type SdfValueTypeNames->Float GetDynamicFrictionAttr() → Attribute Dynamic friction coefficient. Unitless. Declaration float physics:dynamicFriction = 0 C++ Type float Usd Type SdfValueTypeNames->Float GetRestitutionAttr() → Attribute Restitution coefficient. Unitless. Declaration float physics:restitution = 0 C++ Type float Usd Type SdfValueTypeNames->Float static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – GetStaticFrictionAttr() → Attribute Static friction coefficient. Unitless. Declaration float physics:staticFriction = 0 C++ Type float Usd Type SdfValueTypeNames->Float class pxr.UsdPhysics.MeshCollisionAPI Attributes to control how a Mesh is made into a collider. Can be applied to only a USDGeomMesh in addition to its PhysicsCollisionAPI. For any described attribute Fallback Value or Allowed Values below that are text/tokens, the actual token is published and defined in UsdPhysicsTokens. So to set an attribute to the value”rightHanded”, use UsdPhysicsTokens->rightHanded as the value. Methods: Apply classmethod Apply(prim) -> MeshCollisionAPI CanApply classmethod CanApply(prim, whyNot) -> bool CreateApproximationAttr(defaultValue, ...) See GetApproximationAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Get classmethod Get(stage, path) -> MeshCollisionAPI GetApproximationAttr() Determines the mesh's collision approximation:"none"- The mesh geometry is used directly as a collider without any approximation. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] static Apply() classmethod Apply(prim) -> MeshCollisionAPI Applies this single-apply API schema to the given prim . This information is stored by adding”PhysicsMeshCollisionAPI”to the token-valued, listOp metadata apiSchemas on the prim. A valid UsdPhysicsMeshCollisionAPI object is returned upon success. An invalid (or empty) UsdPhysicsMeshCollisionAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – static CanApply() classmethod CanApply(prim, whyNot) -> bool Returns true if this single-apply API schema can be applied to the given prim . If this schema can not be a applied to the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – whyNot (str) – CreateApproximationAttr(defaultValue, writeSparsely) → Attribute See GetApproximationAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Get() classmethod Get(stage, path) -> MeshCollisionAPI Return a UsdPhysicsMeshCollisionAPI 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: UsdPhysicsMeshCollisionAPI(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetApproximationAttr() → Attribute Determines the mesh’s collision approximation:”none”- The mesh geometry is used directly as a collider without any approximation. “convexDecomposition”- A convex mesh decomposition is performed. This results in a set of convex mesh colliders.”convexHull”- A convex hull of the mesh is generated and used as the collider.”boundingSphere”- A bounding sphere is computed around the mesh and used as a collider.”boundingCube”- An optimally fitting box collider is computed around the mesh.”meshSimplification”- A mesh simplification step is performed, resulting in a simplified triangle mesh collider. Declaration uniform token physics:approximation ="none" C++ Type TfToken Usd Type SdfValueTypeNames->Token Variability SdfVariabilityUniform Allowed Values none, convexDecomposition, convexHull, boundingSphere, boundingCube, meshSimplification static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.PrismaticJoint Predefined prismatic joint type (translation along prismatic joint axis is permitted.) For any described attribute Fallback Value or Allowed Values below that are text/tokens, the actual token is published and defined in UsdPhysicsTokens. So to set an attribute to the value”rightHanded”, use UsdPhysicsTokens->rightHanded as the value. Methods: CreateAxisAttr(defaultValue, writeSparsely) See GetAxisAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateLowerLimitAttr(defaultValue, writeSparsely) See GetLowerLimitAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateUpperLimitAttr(defaultValue, writeSparsely) See GetUpperLimitAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Define classmethod Define(stage, path) -> PrismaticJoint Get classmethod Get(stage, path) -> PrismaticJoint GetAxisAttr() Joint axis. GetLowerLimitAttr() Lower limit. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] GetUpperLimitAttr() Upper limit. CreateAxisAttr(defaultValue, writeSparsely) → Attribute See GetAxisAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateLowerLimitAttr(defaultValue, writeSparsely) → Attribute See GetLowerLimitAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateUpperLimitAttr(defaultValue, writeSparsely) → Attribute See GetUpperLimitAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Define() classmethod Define(stage, path) -> PrismaticJoint 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. Parameters stage (Stage) – path (Path) – static Get() classmethod Get(stage, path) -> PrismaticJoint Return a UsdPhysicsPrismaticJoint 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: UsdPhysicsPrismaticJoint(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetAxisAttr() → Attribute Joint axis. Declaration uniform token physics:axis ="X" C++ Type TfToken Usd Type SdfValueTypeNames->Token Variability SdfVariabilityUniform Allowed Values X, Y, Z GetLowerLimitAttr() → Attribute Lower limit. Units: distance. -inf means not limited in negative direction. Declaration float physics:lowerLimit = -inf C++ Type float Usd Type SdfValueTypeNames->Float static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – GetUpperLimitAttr() → Attribute Upper limit. Units: distance. inf means not limited in positive direction. Declaration float physics:upperLimit = inf C++ Type float Usd Type SdfValueTypeNames->Float class pxr.UsdPhysics.RevoluteJoint Predefined revolute joint type (rotation along revolute joint axis is permitted.) For any described attribute Fallback Value or Allowed Values below that are text/tokens, the actual token is published and defined in UsdPhysicsTokens. So to set an attribute to the value”rightHanded”, use UsdPhysicsTokens->rightHanded as the value. Methods: CreateAxisAttr(defaultValue, writeSparsely) See GetAxisAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateLowerLimitAttr(defaultValue, writeSparsely) See GetLowerLimitAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateUpperLimitAttr(defaultValue, writeSparsely) See GetUpperLimitAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Define classmethod Define(stage, path) -> RevoluteJoint Get classmethod Get(stage, path) -> RevoluteJoint GetAxisAttr() Joint axis. GetLowerLimitAttr() Lower limit. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] GetUpperLimitAttr() Upper limit. CreateAxisAttr(defaultValue, writeSparsely) → Attribute See GetAxisAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateLowerLimitAttr(defaultValue, writeSparsely) → Attribute See GetLowerLimitAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateUpperLimitAttr(defaultValue, writeSparsely) → Attribute See GetUpperLimitAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Define() classmethod Define(stage, path) -> RevoluteJoint 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. Parameters stage (Stage) – path (Path) – static Get() classmethod Get(stage, path) -> RevoluteJoint Return a UsdPhysicsRevoluteJoint 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: UsdPhysicsRevoluteJoint(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetAxisAttr() → Attribute Joint axis. Declaration uniform token physics:axis ="X" C++ Type TfToken Usd Type SdfValueTypeNames->Token Variability SdfVariabilityUniform Allowed Values X, Y, Z GetLowerLimitAttr() → Attribute Lower limit. Units: degrees. -inf means not limited in negative direction. Declaration float physics:lowerLimit = -inf C++ Type float Usd Type SdfValueTypeNames->Float static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – GetUpperLimitAttr() → Attribute Upper limit. Units: degrees. inf means not limited in positive direction. Declaration float physics:upperLimit = inf C++ Type float Usd Type SdfValueTypeNames->Float class pxr.UsdPhysics.RigidBodyAPI Applies physics body attributes to any UsdGeomXformable prim and marks that prim to be driven by a simulation. If a simulation is running it will update this prim’s pose. All prims in the hierarchy below this prim should move accordingly. Classes: MassInformation Methods: Apply classmethod Apply(prim) -> RigidBodyAPI CanApply classmethod CanApply(prim, whyNot) -> bool ComputeMassProperties(diagonalInertia, com, ...) Compute mass properties of the rigid body diagonalInertia Computed diagonal of the inertial tensor for the rigid body. CreateAngularVelocityAttr(defaultValue, ...) See GetAngularVelocityAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateKinematicEnabledAttr(defaultValue, ...) See GetKinematicEnabledAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateRigidBodyEnabledAttr(defaultValue, ...) See GetRigidBodyEnabledAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateSimulationOwnerRel() See GetSimulationOwnerRel() , and also Create vs Get Property Methods for when to use Get vs Create. CreateStartsAsleepAttr(defaultValue, ...) See GetStartsAsleepAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateVelocityAttr(defaultValue, writeSparsely) See GetVelocityAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Get classmethod Get(stage, path) -> RigidBodyAPI GetAngularVelocityAttr() Angular velocity in the same space as the node's xform. GetKinematicEnabledAttr() Determines whether the body is kinematic or not. GetRigidBodyEnabledAttr() Determines if this PhysicsRigidBodyAPI is enabled. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] GetSimulationOwnerRel() Single PhysicsScene that will simulate this body. GetStartsAsleepAttr() Determines if the body is asleep when the simulation starts. GetVelocityAttr() Linear velocity in the same space as the node's xform. class MassInformation Attributes: centerOfMass inertia localPos localRot volume property centerOfMass property inertia property localPos property localRot property volume static Apply() classmethod Apply(prim) -> RigidBodyAPI Applies this single-apply API schema to the given prim . This information is stored by adding”PhysicsRigidBodyAPI”to the token- valued, listOp metadata apiSchemas on the prim. A valid UsdPhysicsRigidBodyAPI object is returned upon success. An invalid (or empty) UsdPhysicsRigidBodyAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – static CanApply() classmethod CanApply(prim, whyNot) -> bool Returns true if this single-apply API schema can be applied to the given prim . If this schema can not be a applied to the prim, this returns false and, if provided, populates whyNot with the reason it can not be applied. Note that if CanApply returns false, that does not necessarily imply that calling Apply will fail. Callers are expected to call CanApply before calling Apply if they want to ensure that it is valid to apply a schema. UsdPrim::GetAppliedSchemas() UsdPrim::HasAPI() UsdPrim::CanApplyAPI() UsdPrim::ApplyAPI() UsdPrim::RemoveAPI() Parameters prim (Prim) – whyNot (str) – ComputeMassProperties(diagonalInertia, com, principalAxes, massInfoFn) → float Compute mass properties of the rigid body diagonalInertia Computed diagonal of the inertial tensor for the rigid body. com Computed center of mass for the rigid body. principalAxes Inertia tensor’s principal axes orienttion for the rigid body. massInfoFn Callback function to get collision mass information. Computed mass of the rigid body Parameters diagonalInertia (Vec3f) – com (Vec3f) – principalAxes (Quatf) – massInfoFn (MassInformationFn) – CreateAngularVelocityAttr(defaultValue, writeSparsely) → Attribute See GetAngularVelocityAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateKinematicEnabledAttr(defaultValue, writeSparsely) → Attribute See GetKinematicEnabledAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateRigidBodyEnabledAttr(defaultValue, writeSparsely) → Attribute See GetRigidBodyEnabledAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateSimulationOwnerRel() → Relationship See GetSimulationOwnerRel() , and also Create vs Get Property Methods for when to use Get vs Create. CreateStartsAsleepAttr(defaultValue, writeSparsely) → Attribute See GetStartsAsleepAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateVelocityAttr(defaultValue, writeSparsely) → Attribute See GetVelocityAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Get() classmethod Get(stage, path) -> RigidBodyAPI Return a UsdPhysicsRigidBodyAPI 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: UsdPhysicsRigidBodyAPI(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetAngularVelocityAttr() → Attribute Angular velocity in the same space as the node’s xform. Units: degrees/second. Declaration vector3f physics:angularVelocity = (0, 0, 0) C++ Type GfVec3f Usd Type SdfValueTypeNames->Vector3f GetKinematicEnabledAttr() → Attribute Determines whether the body is kinematic or not. A kinematic body is a body that is moved through animated poses or through user defined poses. The simulation derives velocities for the kinematic body based on the external motion. When a continuous motion is not desired, this kinematic flag should be set to false. Declaration bool physics:kinematicEnabled = 0 C++ Type bool Usd Type SdfValueTypeNames->Bool GetRigidBodyEnabledAttr() → Attribute Determines if this PhysicsRigidBodyAPI is enabled. Declaration bool physics:rigidBodyEnabled = 1 C++ Type bool Usd Type SdfValueTypeNames->Bool static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – GetSimulationOwnerRel() → Relationship Single PhysicsScene that will simulate this body. By default this is the first PhysicsScene found in the stage using UsdStage::Traverse() . GetStartsAsleepAttr() → Attribute Determines if the body is asleep when the simulation starts. Declaration uniform bool physics:startsAsleep = 0 C++ Type bool Usd Type SdfValueTypeNames->Bool Variability SdfVariabilityUniform GetVelocityAttr() → Attribute Linear velocity in the same space as the node’s xform. Units: distance/second. Declaration vector3f physics:velocity = (0, 0, 0) C++ Type GfVec3f Usd Type SdfValueTypeNames->Vector3f class pxr.UsdPhysics.Scene General physics simulation properties, required for simulation. Methods: CreateGravityDirectionAttr(defaultValue, ...) See GetGravityDirectionAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateGravityMagnitudeAttr(defaultValue, ...) See GetGravityMagnitudeAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Define classmethod Define(stage, path) -> Scene Get classmethod Get(stage, path) -> Scene GetGravityDirectionAttr() Gravity direction vector in simulation world space. GetGravityMagnitudeAttr() Gravity acceleration magnitude in simulation world space. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] CreateGravityDirectionAttr(defaultValue, writeSparsely) → Attribute See GetGravityDirectionAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateGravityMagnitudeAttr(defaultValue, writeSparsely) → Attribute See GetGravityMagnitudeAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Define() classmethod Define(stage, path) -> Scene 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. Parameters stage (Stage) – path (Path) – static Get() classmethod Get(stage, path) -> Scene Return a UsdPhysicsScene 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: UsdPhysicsScene(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetGravityDirectionAttr() → Attribute Gravity direction vector in simulation world space. Will be normalized before use. A zero vector is a request to use the negative upAxis. Unitless. Declaration vector3f physics:gravityDirection = (0, 0, 0) C++ Type GfVec3f Usd Type SdfValueTypeNames->Vector3f GetGravityMagnitudeAttr() → Attribute Gravity acceleration magnitude in simulation world space. A negative value is a request to use a value equivalent to earth gravity regardless of the metersPerUnit scaling used by this scene. Units: distance/second/second. Declaration float physics:gravityMagnitude = -inf C++ Type float Usd Type SdfValueTypeNames->Float static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.SphericalJoint Predefined spherical joint type (Removes linear degrees of freedom, cone limit may restrict the motion in a given range.) It allows two limit values, which when equal create a circular, else an elliptic cone limit around the limit axis. For any described attribute Fallback Value or Allowed Values below that are text/tokens, the actual token is published and defined in UsdPhysicsTokens. So to set an attribute to the value”rightHanded”, use UsdPhysicsTokens->rightHanded as the value. Methods: CreateAxisAttr(defaultValue, writeSparsely) See GetAxisAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateConeAngle0LimitAttr(defaultValue, ...) See GetConeAngle0LimitAttr() , and also Create vs Get Property Methods for when to use Get vs Create. CreateConeAngle1LimitAttr(defaultValue, ...) See GetConeAngle1LimitAttr() , and also Create vs Get Property Methods for when to use Get vs Create. Define classmethod Define(stage, path) -> SphericalJoint Get classmethod Get(stage, path) -> SphericalJoint GetAxisAttr() Cone limit axis. GetConeAngle0LimitAttr() Cone limit from the primary joint axis in the local0 frame toward the next axis. GetConeAngle1LimitAttr() Cone limit from the primary joint axis in the local0 frame toward the second to next axis. GetSchemaAttributeNames classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] CreateAxisAttr(defaultValue, writeSparsely) → Attribute See GetAxisAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateConeAngle0LimitAttr(defaultValue, writeSparsely) → Attribute See GetConeAngle0LimitAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – CreateConeAngle1LimitAttr(defaultValue, writeSparsely) → Attribute See GetConeAngle1LimitAttr() , 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 . Parameters defaultValue (VtValue) – writeSparsely (bool) – static Define() classmethod Define(stage, path) -> SphericalJoint 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. Parameters stage (Stage) – path (Path) – static Get() classmethod Get(stage, path) -> SphericalJoint Return a UsdPhysicsSphericalJoint 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: UsdPhysicsSphericalJoint(stage->GetPrimAtPath(path)); Parameters stage (Stage) – path (Path) – GetAxisAttr() → Attribute Cone limit axis. Declaration uniform token physics:axis ="X" C++ Type TfToken Usd Type SdfValueTypeNames->Token Variability SdfVariabilityUniform Allowed Values X, Y, Z GetConeAngle0LimitAttr() → Attribute Cone limit from the primary joint axis in the local0 frame toward the next axis. (Next axis of X is Y, and of Z is X.) A negative value means not limited. Units: degrees. Declaration float physics:coneAngle0Limit = -1 C++ Type float Usd Type SdfValueTypeNames->Float GetConeAngle1LimitAttr() → Attribute Cone limit from the primary joint axis in the local0 frame toward the second to next axis. A negative value means not limited. Units: degrees. Declaration float physics:coneAngle1Limit = -1 C++ Type float Usd Type SdfValueTypeNames->Float static GetSchemaAttributeNames() classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken] 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. Parameters includeInherited (bool) – class pxr.UsdPhysics.Tokens Attributes: acceleration angular boundingCube boundingSphere colliders convexDecomposition convexHull distance drive drive_MultipleApplyTemplate_PhysicsDamping drive_MultipleApplyTemplate_PhysicsMaxForce drive_MultipleApplyTemplate_PhysicsStiffness drive_MultipleApplyTemplate_PhysicsTargetPosition drive_MultipleApplyTemplate_PhysicsTargetVelocity drive_MultipleApplyTemplate_PhysicsType force kilogramsPerUnit limit limit_MultipleApplyTemplate_PhysicsHigh limit_MultipleApplyTemplate_PhysicsLow linear meshSimplification none physicsAngularVelocity physicsApproximation physicsAxis physicsBody0 physicsBody1 physicsBreakForce physicsBreakTorque physicsCenterOfMass physicsCollisionEnabled physicsConeAngle0Limit physicsConeAngle1Limit physicsDensity physicsDiagonalInertia physicsDynamicFriction physicsExcludeFromArticulation physicsFilteredGroups physicsFilteredPairs physicsGravityDirection physicsGravityMagnitude physicsInvertFilteredGroups physicsJointEnabled physicsKinematicEnabled physicsLocalPos0 physicsLocalPos1 physicsLocalRot0 physicsLocalRot1 physicsLowerLimit physicsMass physicsMaxDistance physicsMergeGroup physicsMinDistance physicsPrincipalAxes physicsRestitution physicsRigidBodyEnabled physicsSimulationOwner physicsStartsAsleep physicsStaticFriction physicsUpperLimit physicsVelocity rotX rotY rotZ transX transY transZ x y z acceleration = 'acceleration' angular = 'angular' boundingCube = 'boundingCube' boundingSphere = 'boundingSphere' colliders = 'colliders' convexDecomposition = 'convexDecomposition' convexHull = 'convexHull' distance = 'distance' drive = 'drive' drive_MultipleApplyTemplate_PhysicsDamping = 'drive:__INSTANCE_NAME__:physics:damping' drive_MultipleApplyTemplate_PhysicsMaxForce = 'drive:__INSTANCE_NAME__:physics:maxForce' drive_MultipleApplyTemplate_PhysicsStiffness = 'drive:__INSTANCE_NAME__:physics:stiffness' drive_MultipleApplyTemplate_PhysicsTargetPosition = 'drive:__INSTANCE_NAME__:physics:targetPosition' drive_MultipleApplyTemplate_PhysicsTargetVelocity = 'drive:__INSTANCE_NAME__:physics:targetVelocity' drive_MultipleApplyTemplate_PhysicsType = 'drive:__INSTANCE_NAME__:physics:type' force = 'force' kilogramsPerUnit = 'kilogramsPerUnit' limit = 'limit' limit_MultipleApplyTemplate_PhysicsHigh = 'limit:__INSTANCE_NAME__:physics:high' limit_MultipleApplyTemplate_PhysicsLow = 'limit:__INSTANCE_NAME__:physics:low' linear = 'linear' meshSimplification = 'meshSimplification' none = 'none' physicsAngularVelocity = 'physics:angularVelocity' physicsApproximation = 'physics:approximation' physicsAxis = 'physics:axis' physicsBody0 = 'physics:body0' physicsBody1 = 'physics:body1' physicsBreakForce = 'physics:breakForce' physicsBreakTorque = 'physics:breakTorque' physicsCenterOfMass = 'physics:centerOfMass' physicsCollisionEnabled = 'physics:collisionEnabled' physicsConeAngle0Limit = 'physics:coneAngle0Limit' physicsConeAngle1Limit = 'physics:coneAngle1Limit' physicsDensity = 'physics:density' physicsDiagonalInertia = 'physics:diagonalInertia' physicsDynamicFriction = 'physics:dynamicFriction' physicsExcludeFromArticulation = 'physics:excludeFromArticulation' physicsFilteredGroups = 'physics:filteredGroups' physicsFilteredPairs = 'physics:filteredPairs' physicsGravityDirection = 'physics:gravityDirection' physicsGravityMagnitude = 'physics:gravityMagnitude' physicsInvertFilteredGroups = 'physics:invertFilteredGroups' physicsJointEnabled = 'physics:jointEnabled' physicsKinematicEnabled = 'physics:kinematicEnabled' physicsLocalPos0 = 'physics:localPos0' physicsLocalPos1 = 'physics:localPos1' physicsLocalRot0 = 'physics:localRot0' physicsLocalRot1 = 'physics:localRot1' physicsLowerLimit = 'physics:lowerLimit' physicsMass = 'physics:mass' physicsMaxDistance = 'physics:maxDistance' physicsMergeGroup = 'physics:mergeGroup' physicsMinDistance = 'physics:minDistance' physicsPrincipalAxes = 'physics:principalAxes' physicsRestitution = 'physics:restitution' physicsRigidBodyEnabled = 'physics:rigidBodyEnabled' physicsSimulationOwner = 'physics:simulationOwner' physicsStartsAsleep = 'physics:startsAsleep' physicsStaticFriction = 'physics:staticFriction' physicsUpperLimit = 'physics:upperLimit' physicsVelocity = 'physics:velocity' rotX = 'rotX' rotY = 'rotY' rotZ = 'rotZ' transX = 'transX' transY = 'transY' transZ = 'transZ' x = 'X' y = 'Y' z = 'Z' © Copyright 2019-2023, NVIDIA. Last updated on Nov 14, 2023.