usdrt::UsdShadeConnectableAPI

Defined in usdrt/scenegraph/usd/usdShade/connectableAPI.h

class UsdShadeConnectableAPI : public usdrt::UsdAPISchemaBase 

UsdShadeConnectableAPI is an API schema that provides a common interface for creating outputs and making connections between shading parameters and outputs. The interface is common to all UsdShade schemas that support Inputs and Outputs, which currently includes UsdShadeShader, UsdShadeNodeGraph, and UsdShadeMaterial .

One can construct a UsdShadeConnectableAPI directly from a UsdPrim, or from objects of any of the schema classes listed above. If it seems onerous to need to construct a secondary schema object to interact with Inputs and Outputs, keep in mind that any function whose purpose is either to walk material/shader networks via their connections, or to create such networks, can typically be written entirely in terms of UsdShadeConnectableAPI objects, without needing to care what the underlying prim type is.

Additionally, the most common UsdShadeConnectableAPI behaviors (creating Inputs and Outputs, and making connections) are wrapped as convenience methods on the prim schema classes (creation) and UsdShadeInput and UsdShadeOutput.

Outputs

inline UsdShadeOutput CreateOutput(const TfToken &name, const SdfValueTypeName &typeName) const

Create an output, which represents and externally computed, typed value. Outputs on node-graphs can be connected.

The attribute representing an output is created in the “outputs:” namespace.

inline UsdShadeOutput GetOutput(const TfToken &name) const

Return the requested output if it exists.

name is the unnamespaced base name.

inline std::vector<UsdShadeOutput> GetOutputs(bool onlyAuthored = true) const: Returns all outputs on the connectable prim (i.e. shader or node-graph). Outputs are represented by attributes in the “outputs:” namespace. If onlyAuthored is true (the default), then only return authored attributes; otherwise, this also returns un-authored builtins.

Inputs

inline UsdShadeInput CreateInput(const TfToken &name, const SdfValueTypeName &typeName) const: Create an input which can both have a value and be connected. The attribute representing the input is created in the “inputs:” namespace.

inline UsdShadeInput GetInput(const TfToken &name) const

Return the requested input if it exists.

name is the unnamespaced base name.

inline std::vector<UsdShadeInput> GetInputs(bool onlyAuthored = true) const: Returns all inputs on the connectable prim (i.e. shader or node-graph). Inputs are represented by attributes in the “inputs:” namespace. If onlyAuthored is true (the default), then only return authored attributes; otherwise, this also returns un-authored builtins.

Public Types

using ConnectionModification = UsdShadeConnectionModification 

Public Functions

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

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

inline virtual ~UsdShadeConnectableAPI(): Destructor.

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

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

inline explicit operator bool() const

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

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

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

This method invokes polymorphic behaviour.