UsdShade.md

UsdShade module — pxr-usd-api 105.1 documentation

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UsdShade module

 

# UsdShade module

Summary: The UsdShade module provides schemas and behaviors for creating and binding materials, which encapsulate shading networks.

Classes:

AttributeType

ConnectableAPI
UsdShadeConnectableAPI is an API schema that provides a common interface for creating outputs and making connections between shading parameters and outputs.

ConnectionModification

ConnectionSourceInfo
A compact struct to represent a bundle of information about an upstream source attribute.

CoordSysAPI
UsdShadeCoordSysAPI provides a way to designate, name, and discover coordinate systems.

Input
This class encapsulates a shader or node-graph input, which is a connectable attribute representing a typed value.

Material
A Material provides a container into which multiple"render targets"can add data that defines a"shading material"for a renderer.

MaterialBindingAPI
UsdShadeMaterialBindingAPI is an API schema that provides an interface for binding materials to prims or collections of prims (represented by UsdCollectionAPI objects).

NodeDefAPI
UsdShadeNodeDefAPI is an API schema that provides attributes for a prim to select a corresponding Shader Node Definition ("Sdr Node"), as well as to look up a runtime entry for that shader node in the form of an SdrShaderNode.

NodeGraph
A node-graph is a container for shading nodes, as well as other node- graphs.

Output
This class encapsulates a shader or node-graph output, which is a connectable attribute representing a typed, externally computed value.

Shader
Base class for all USD shaders.

ShaderDefParserPlugin
Parses shader definitions represented using USD scene description using the schemas provided by UsdShade.

ShaderDefUtils
This class contains a set of utility functions used for populating the shader registry with shaders definitions specified using UsdShade schemas.

Tokens

Utils
This class contains a set of utility functions used when authoring and querying shading networks.

class pxr.UsdShade.AttributeType
Attributes:

Input

Invalid

Output

names

values

Input = pxr.UsdShade.AttributeType.Input

Invalid = pxr.UsdShade.AttributeType.Invalid

Output = pxr.UsdShade.AttributeType.Output

names = {'Input': pxr.UsdShade.AttributeType.Input, 'Invalid': pxr.UsdShade.AttributeType.Invalid, 'Output': pxr.UsdShade.AttributeType.Output}

values = {0: pxr.UsdShade.AttributeType.Invalid, 1: pxr.UsdShade.AttributeType.Input, 2: pxr.UsdShade.AttributeType.Output}

class pxr.UsdShade.ConnectableAPI
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.
Methods:

CanConnect
classmethod CanConnect(input, source) -> bool

ClearSource
classmethod ClearSource(shadingAttr) -> bool

ClearSources
classmethod ClearSources(shadingAttr) -> bool

ConnectToSource
classmethod ConnectToSource(shadingAttr, source, mod) -> bool

CreateInput(name, typeName)
Create an input which can both have a value and be connected.

CreateOutput(name, typeName)
Create an output, which represents and externally computed, typed value.

DisconnectSource
classmethod DisconnectSource(shadingAttr, sourceAttr) -> bool

Get
classmethod Get(stage, path) -> ConnectableAPI

GetConnectedSource
classmethod GetConnectedSource(shadingAttr, source, sourceName, sourceType) -> bool

GetConnectedSources
classmethod GetConnectedSources(shadingAttr, invalidSourcePaths) -> list[UsdShadeSourceInfo]

GetInput(name)
Return the requested input if it exists.

GetInputs(onlyAuthored)
Returns all inputs on the connectable prim (i.e.

GetOutput(name)
Return the requested output if it exists.

GetOutputs(onlyAuthored)
Returns all outputs on the connectable prim (i.e.

GetRawConnectedSourcePaths
classmethod GetRawConnectedSourcePaths(shadingAttr, sourcePaths) -> bool

GetSchemaAttributeNames
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]

HasConnectableAPI
classmethod HasConnectableAPI(schemaType) -> bool

HasConnectedSource
classmethod HasConnectedSource(shadingAttr) -> bool

IsContainer()
Returns true if the prim is a container.

IsSourceConnectionFromBaseMaterial
classmethod IsSourceConnectionFromBaseMaterial(shadingAttr) -> bool

RequiresEncapsulation()
Returns true if container encapsulation rules should be respected when evaluating connectibility behavior, false otherwise.

SetConnectedSources
classmethod SetConnectedSources(shadingAttr, sourceInfos) -> bool

static CanConnect()
classmethod CanConnect(input, source) -> bool
Determines whether the given input can be connected to the given
source attribute, which can be an input or an output.
The result depends on the”connectability”of the input and the source
attributes. Depending on the prim type, this may require the plugin
that defines connectability behavior for that prim type be loaded.
UsdShadeInput::SetConnectability
UsdShadeInput::GetConnectability

Parameters

input (Input) – 
source (Attribute) – 

CanConnect(input, sourceInput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
sourceInput (Input) – 

CanConnect(input, sourceOutput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
sourceOutput (Output) – 

CanConnect(output, source) -> bool
Determines whether the given output can be connected to the given
source attribute, which can be an input or an output.
An output is considered to be connectable only if it belongs to a
node-graph. Shader outputs are not connectable.
source is an optional argument. If a valid UsdAttribute is
supplied for it, this method will return true only if the source
attribute is owned by a descendant of the node-graph owning the
output.

Parameters

output (Output) – 
source (Attribute) – 

CanConnect(output, sourceInput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
sourceInput (Input) – 

CanConnect(output, sourceOutput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
sourceOutput (Output) – 

static ClearSource()
classmethod ClearSource(shadingAttr) -> bool
Deprecated
This is the older version that only referenced a single source. Please
use ClearSources instead.

Parameters
shadingAttr (Attribute) – 

ClearSource(input) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
input (Input) – 

ClearSource(output) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
output (Output) – 

static ClearSources()
classmethod ClearSources(shadingAttr) -> bool
Clears sources for this shading attribute in the current
UsdEditTarget.
Most of the time, what you probably want is DisconnectSource() rather
than this function.
DisconnectSource()

Parameters
shadingAttr (Attribute) – 

ClearSources(input) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
input (Input) – 

ClearSources(output) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
output (Output) – 

static ConnectToSource()
classmethod ConnectToSource(shadingAttr, source, mod) -> bool
Authors a connection for a given shading attribute shadingAttr .
shadingAttr can represent a parameter, an input or an output.
source is a struct that describes the upstream source attribute
with all the information necessary to make a connection. See the
documentation for UsdShadeConnectionSourceInfo. mod describes the
operation that should be applied to the list of connections. By
default the new connection will replace any existing connections, but
it can add to the list of connections to represent multiple input
connections.
true if a connection was created successfully. false if
shadingAttr or source is invalid.
This method does not verify the connectability of the shading
attribute to the source. Clients must invoke CanConnect() themselves
to ensure compatibility.
The source shading attribute is created if it doesn’t exist already.

Parameters

shadingAttr (Attribute) – 
source (ConnectionSourceInfo) – 
mod (ConnectionModification) – 

ConnectToSource(input, source, mod) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
source (ConnectionSourceInfo) – 
mod (ConnectionModification) – 

ConnectToSource(output, source, mod) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
source (ConnectionSourceInfo) – 
mod (ConnectionModification) – 

ConnectToSource(shadingAttr, source, sourceName, sourceType, typeName) -> bool
Deprecated
Please use the versions that take a UsdShadeConnectionSourceInfo to
describe the upstream source This is an overloaded member function,
provided for convenience. It differs from the above function only in
what argument(s) it accepts.

Parameters

shadingAttr (Attribute) – 
source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 
typeName (ValueTypeName) – 

ConnectToSource(input, source, sourceName, sourceType, typeName) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 
typeName (ValueTypeName) – 

ConnectToSource(output, source, sourceName, sourceType, typeName) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 
typeName (ValueTypeName) – 

ConnectToSource(shadingAttr, sourcePath) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.
Connect the given shading attribute to the source at path,
sourcePath .
sourcePath should be the fully namespaced property path.
This overload is provided for convenience, for use in contexts where
the prim types are unknown or unavailable.

Parameters

shadingAttr (Attribute) – 
sourcePath (Path) – 

ConnectToSource(input, sourcePath) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
sourcePath (Path) – 

ConnectToSource(output, sourcePath) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
sourcePath (Path) – 

ConnectToSource(shadingAttr, sourceInput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.
Connect the given shading attribute to the given source input.

Parameters

shadingAttr (Attribute) – 
sourceInput (Input) – 

ConnectToSource(input, sourceInput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
sourceInput (Input) – 

ConnectToSource(output, sourceInput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
sourceInput (Input) – 

ConnectToSource(shadingAttr, sourceOutput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.
Connect the given shading attribute to the given source output.

Parameters

shadingAttr (Attribute) – 
sourceOutput (Output) – 

ConnectToSource(input, sourceOutput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
sourceOutput (Output) – 

ConnectToSource(output, sourceOutput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
sourceOutput (Output) – 

CreateInput(name, typeName) → Input
Create an input which can both have a value and be connected.
The attribute representing the input is created in
the”inputs:”namespace.

Parameters

name (str) – 
typeName (ValueTypeName) – 

CreateOutput(name, typeName) → Output
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.

Parameters

name (str) – 
typeName (ValueTypeName) – 

static DisconnectSource()
classmethod DisconnectSource(shadingAttr, sourceAttr) -> bool
Disconnect source for this shading attribute.
If sourceAttr is valid it will disconnect the connection to this
upstream attribute. Otherwise it will disconnect all connections by
authoring an empty list of connections for the attribute
shadingAttr .
This may author more scene description than you might expect - we
define the behavior of disconnect to be that, even if a shading
attribute becomes connected in a weaker layer than the current
UsdEditTarget, the attribute will still be disconnected in the
composition, therefore we must”block”it in the current UsdEditTarget.
ConnectToSource() .

Parameters

shadingAttr (Attribute) – 
sourceAttr (Attribute) – 

DisconnectSource(input, sourceAttr) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
sourceAttr (Attribute) – 

DisconnectSource(output, sourceAttr) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
sourceAttr (Attribute) – 

static Get()
classmethod Get(stage, path) -> ConnectableAPI
Return a UsdShadeConnectableAPI 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:
UsdShadeConnectableAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

static GetConnectedSource()
classmethod GetConnectedSource(shadingAttr, source, sourceName, sourceType) -> bool
Deprecated
Shading attributes can have multiple connections and so using
GetConnectedSources is needed in general
Finds the source of a connection for the given shading attribute.
shadingAttr is the shading attribute whose connection we want to
interrogate. source is an output parameter which will be set to
the source connectable prim. sourceName will be set to the name of
the source shading attribute, which may be an input or an output, as
specified by sourceType sourceType will have the type of the
source shading attribute, i.e. whether it is an Input or
Output
true if the shading attribute is connected to a valid, defined
source attribute. false if the shading attribute is not connected
to a single, defined source attribute.
Previously this method would silently return false for multiple
connections. We are changing the behavior of this method to return the
result for the first connection and issue a TfWarn about it. We want
to encourage clients to use GetConnectedSources going forward.
The python wrapping for this method returns a (source, sourceName,
sourceType) tuple if the parameter is connected, else None

Parameters

shadingAttr (Attribute) – 
source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 

GetConnectedSource(input, source, sourceName, sourceType) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 

GetConnectedSource(output, source, sourceName, sourceType) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 

static GetConnectedSources()
classmethod GetConnectedSources(shadingAttr, invalidSourcePaths) -> list[UsdShadeSourceInfo]
Finds the valid sources of connections for the given shading
attribute.
shadingAttr is the shading attribute whose connections we want to
interrogate. invalidSourcePaths is an optional output parameter to
collect the invalid source paths that have not been reported in the
returned vector.
Returns a vector of UsdShadeConnectionSourceInfo structs with
information about each upsteam attribute. If the vector is empty,
there have been no connections.
A valid connection requires the existence of the source attribute and
also requires that the source prim is UsdShadeConnectableAPI
compatible.
The python wrapping returns a tuple with the valid connections first,
followed by the invalid source paths.

Parameters

shadingAttr (Attribute) – 
invalidSourcePaths (list[SdfPath]) – 

GetConnectedSources(input, invalidSourcePaths) -> list[UsdShadeSourceInfo]
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
invalidSourcePaths (list[SdfPath]) – 

GetConnectedSources(output, invalidSourcePaths) -> list[UsdShadeSourceInfo]
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
invalidSourcePaths (list[SdfPath]) – 

GetInput(name) → Input
Return the requested input if it exists.
name is the unnamespaced base name.

Parameters
name (str) – 

GetInputs(onlyAuthored) → list[Input]
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.

Parameters
onlyAuthored (bool) – 

GetOutput(name) → Output
Return the requested output if it exists.
name is the unnamespaced base name.

Parameters
name (str) – 

GetOutputs(onlyAuthored) → list[Output]
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.

Parameters
onlyAuthored (bool) – 

static GetRawConnectedSourcePaths()
classmethod GetRawConnectedSourcePaths(shadingAttr, sourcePaths) -> bool
Deprecated
Please us GetConnectedSources to retrieve multiple connections
Returns the”raw”(authored) connected source paths for the given
shading attribute.

Parameters

shadingAttr (Attribute) – 
sourcePaths (list[SdfPath]) – 

GetRawConnectedSourcePaths(input, sourcePaths) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

input (Input) – 
sourcePaths (list[SdfPath]) – 

GetRawConnectedSourcePaths(output, sourcePaths) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
sourcePaths (list[SdfPath]) – 

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) – 

static HasConnectableAPI()
classmethod HasConnectableAPI(schemaType) -> bool
Return true if the schemaType has a valid connectableAPIBehavior
registered, false otherwise.
To check if a prim’s connectableAPI has a behavior defined, use
UsdSchemaBase::operator bool() .

Parameters
schemaType (Type) – 

HasConnectableAPI() -> bool
Return true if the schema type T has a connectableAPIBehavior
registered, false otherwise.

static HasConnectedSource()
classmethod HasConnectedSource(shadingAttr) -> bool
Returns true if and only if the shading attribute is currently
connected to at least one valid (defined) source.
If you will be calling GetConnectedSources() afterwards anyways, it
will be much faster to instead check if the returned vector is
empty:
UsdShadeSourceInfoVector connections =
    UsdShadeConnectableAPI::GetConnectedSources(attribute);
if (!connections.empty()){
     // process connected attribute
} else {
     // process unconnected attribute
}

Parameters
shadingAttr (Attribute) – 

HasConnectedSource(input) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
input (Input) – 

HasConnectedSource(output) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
output (Output) – 

IsContainer() → bool
Returns true if the prim is a container.
The underlying prim type may provide runtime behavior that defines
whether it is a container.

static IsSourceConnectionFromBaseMaterial()
classmethod IsSourceConnectionFromBaseMaterial(shadingAttr) -> bool
Returns true if the connection to the given shading attribute’s
source, as returned by UsdShadeConnectableAPI::GetConnectedSource() ,
is authored across a specializes arc, which is used to denote a base
material.

Parameters
shadingAttr (Attribute) – 

IsSourceConnectionFromBaseMaterial(input) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
input (Input) – 

IsSourceConnectionFromBaseMaterial(output) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
output (Output) – 

RequiresEncapsulation() → bool
Returns true if container encapsulation rules should be respected when
evaluating connectibility behavior, false otherwise.
The underlying prim type may provide runtime behavior that defines if
encapsulation rules are respected or not.

static SetConnectedSources()
classmethod SetConnectedSources(shadingAttr, sourceInfos) -> bool
Authors a list of connections for a given shading attribute
shadingAttr .
shadingAttr can represent a parameter, an input or an output.
sourceInfos is a vector of structs that describes the upstream
source attributes with all the information necessary to make all the
connections. See the documentation for UsdShadeConnectionSourceInfo.
true if all connection were created successfully. false if the
shadingAttr or one of the sources are invalid.
A valid connection is one that has a valid
UsdShadeConnectionSourceInfo , which requires the existence of the
upstream source prim. It does not require the existence of the source
attribute as it will be create if necessary.

Parameters

shadingAttr (Attribute) – 
sourceInfos (list[ConnectionSourceInfo]) – 

class pxr.UsdShade.ConnectionModification
Attributes:

Append

Prepend

Replace

names

values

Append = pxr.UsdShade.ConnectionModification.Append

Prepend = pxr.UsdShade.ConnectionModification.Prepend

Replace = pxr.UsdShade.ConnectionModification.Replace

names = {'Append': pxr.UsdShade.ConnectionModification.Append, 'Prepend': pxr.UsdShade.ConnectionModification.Prepend, 'Replace': pxr.UsdShade.ConnectionModification.Replace}

values = {0: pxr.UsdShade.ConnectionModification.Replace, 1: pxr.UsdShade.ConnectionModification.Prepend, 2: pxr.UsdShade.ConnectionModification.Append}

class pxr.UsdShade.ConnectionSourceInfo
A compact struct to represent a bundle of information about an
upstream source attribute.
Methods:

IsValid()
Return true if this source info is valid for setting up a connection.

Attributes:

source

sourceName

sourceType

typeName

IsValid() → bool
Return true if this source info is valid for setting up a connection.

property source

property sourceName

property sourceType

property typeName

class pxr.UsdShade.CoordSysAPI
UsdShadeCoordSysAPI provides a way to designate, name, and discover
coordinate systems.
Coordinate systems are implicitly established by UsdGeomXformable
prims, using their local space. That coordinate system may be bound
(i.e., named) from another prim. The binding is encoded as a single-
target relationship in the”coordSys:”namespace. Coordinate system
bindings apply to descendants of the prim where the binding is
expressed, but names may be re-bound by descendant prims.
Named coordinate systems are useful in shading workflows. An example
is projection paint, which projects a texture from a certain view (the
paint coordinate system). Using the paint coordinate frame avoids the
need to assign a UV set to the object, and can be a concise way to
project paint across a collection of objects with a single shared
paint coordinate system.
This is a non-applied API schema.
Methods:

Bind(name, path)
Bind the name to the given path.

BlockBinding(name)
Block the indicated coordinate system binding on this prim by blocking targets on the underlying relationship.

CanContainPropertyName
classmethod CanContainPropertyName(name) -> bool

ClearBinding(name, removeSpec)
Clear the indicated coordinate system binding on this prim from the current edit target.

FindBindingsWithInheritance()
Find the list of coordinate system bindings that apply to this prim, including inherited bindings.

Get
classmethod Get(stage, path) -> CoordSysAPI

GetCoordSysRelationshipName
classmethod GetCoordSysRelationshipName(coordSysName) -> str

GetLocalBindings()
Get the list of coordinate system bindings local to this prim.

GetSchemaAttributeNames
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]

HasLocalBindings()
Returns true if the prim has local coordinate system binding opinions.

Bind(name, path) → bool
Bind the name to the given path.
The prim at the given path is expected to be UsdGeomXformable, in
order for the binding to be succesfully resolved.

Parameters

name (str) – 
path (Path) – 

BlockBinding(name) → bool
Block the indicated coordinate system binding on this prim by blocking
targets on the underlying relationship.

Parameters
name (str) – 

static CanContainPropertyName()
classmethod CanContainPropertyName(name) -> bool
Test whether a given name contains the”coordSys:”prefix.

Parameters
name (str) – 

ClearBinding(name, removeSpec) → bool
Clear the indicated coordinate system binding on this prim from the
current edit target.
Only remove the spec if removeSpec is true (leave the spec to
preserve meta-data we may have intentionally authored on the
relationship)

Parameters

name (str) – 
removeSpec (bool) – 

FindBindingsWithInheritance() → list[Binding]
Find the list of coordinate system bindings that apply to this prim,
including inherited bindings.
This computation examines this prim and ancestors for the strongest
binding for each name. A binding expressed by a child prim supercedes
bindings on ancestors.
Note that this API does not validate the prims at the target paths;
they may be of incorrect type, or missing entirely.
Binding relationships with no resolved targets are skipped.

static Get()
classmethod Get(stage, path) -> CoordSysAPI
Return a UsdShadeCoordSysAPI 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:
UsdShadeCoordSysAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

static GetCoordSysRelationshipName()
classmethod GetCoordSysRelationshipName(coordSysName) -> str
Returns the fully namespaced coordinate system relationship name,
given the coordinate system name.

Parameters
coordSysName (str) – 

GetLocalBindings() → list[Binding]
Get the list of coordinate system bindings local to this prim.
This does not process inherited bindings. It does not validate that a
prim exists at the indicated path. If the binding relationship has
multiple targets, only the first is used.

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) – 

HasLocalBindings() → bool
Returns true if the prim has local coordinate system binding opinions.
Note that the resulting binding list may still be empty.

class pxr.UsdShade.Input
This class encapsulates a shader or node-graph input, which is a
connectable attribute representing a typed value.
Methods:

CanConnect(source)
Determines whether this Input can be connected to the given source attribute, which can be an input or an output.

ClearConnectability()
Clears any authored connectability on the Input.

ClearSdrMetadata()
Clears any"sdrMetadata"value authored on the Input in the current EditTarget.

ClearSdrMetadataByKey(key)
Clears the entry corresponding to the given key in the"sdrMetadata"dictionary authored in the current EditTarget.

ClearSource()
Deprecated

ClearSources()
Clears sources for this Input in the current UsdEditTarget.

ConnectToSource(source, mod)
Authors a connection for this Input.

DisconnectSource(sourceAttr)
Disconnect source for this Input.

Get(value, time)
Convenience wrapper for the templated UsdAttribute::Get() .

GetAttr()
Explicit UsdAttribute extractor.

GetBaseName()
Returns the name of the input.

GetConnectability()
Returns the connectability of the Input.

GetConnectedSource(source, sourceName, ...)
Deprecated

GetConnectedSources(invalidSourcePaths)
Finds the valid sources of connections for the Input.

GetDisplayGroup()
Get the displayGroup metadata for this Input, i.e.

GetDocumentation()
Get documentation string for this Input.

GetFullName()
Get the name of the attribute associated with the Input.

GetPrim()
Get the prim that the input belongs to.

GetRawConnectedSourcePaths(sourcePaths)
Deprecated

GetRenderType()
Return this Input's specialized renderType, or an empty token if none was authored.

GetSdrMetadata()
Returns this Input's composed"sdrMetadata"dictionary as a NdrTokenMap.

GetSdrMetadataByKey(key)
Returns the value corresponding to key in the composed sdrMetadata dictionary.

GetTypeName()
Get the"scene description"value type name of the attribute associated with the Input.

GetValueProducingAttribute(attrType)
Deprecated

GetValueProducingAttributes(shaderOutputsOnly)
Find what is connected to this Input recursively.

HasConnectedSource()
Returns true if and only if this Input is currently connected to a valid (defined) source.

HasRenderType()
Return true if a renderType has been specified for this Input.

HasSdrMetadata()
Returns true if the Input has a non-empty composed"sdrMetadata"dictionary value.

HasSdrMetadataByKey(key)
Returns true if there is a value corresponding to the given key in the composed"sdrMetadata"dictionary.

IsInput
classmethod IsInput(attr) -> bool

IsInterfaceInputName
classmethod IsInterfaceInputName(name) -> bool

IsSourceConnectionFromBaseMaterial()
Returns true if the connection to this Input's source, as returned by GetConnectedSource() , is authored across a specializes arc, which is used to denote a base material.

Set(value, time)
Set a value for the Input at time .

SetConnectability(connectability)
Set the connectability of the Input.

SetConnectedSources(sourceInfos)
Connects this Input to the given sources, sourceInfos .

SetDisplayGroup(displayGroup)
Set the displayGroup metadata for this Input, i.e.

SetDocumentation(docs)
Set documentation string for this Input.

SetRenderType(renderType)
Specify an alternative, renderer-specific type to use when emitting/translating this Input, rather than translating based on its GetTypeName()

SetSdrMetadata(sdrMetadata)
Authors the given sdrMetadata value on this Input at the current EditTarget.

SetSdrMetadataByKey(key, value)
Sets the value corresponding to key to the given string value , in the Input's"sdrMetadata"dictionary at the current EditTarget.

CanConnect(source) → bool
Determines whether this Input can be connected to the given source
attribute, which can be an input or an output.
UsdShadeConnectableAPI::CanConnect

Parameters
source (Attribute) – 

CanConnect(sourceInput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
sourceInput (Input) – 

CanConnect(sourceOutput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
sourceOutput (Output) – 

ClearConnectability() → bool
Clears any authored connectability on the Input.

ClearSdrMetadata() → None
Clears any”sdrMetadata”value authored on the Input in the current
EditTarget.

ClearSdrMetadataByKey(key) → None
Clears the entry corresponding to the given key in
the”sdrMetadata”dictionary authored in the current EditTarget.

Parameters
key (str) – 

ClearSource() → bool
Deprecated

ClearSources() → bool
Clears sources for this Input in the current UsdEditTarget.
Most of the time, what you probably want is DisconnectSource() rather
than this function.
UsdShadeConnectableAPI::ClearSources

ConnectToSource(source, mod) → bool
Authors a connection for this Input.
source is a struct that describes the upstream source attribute
with all the information necessary to make a connection. See the
documentation for UsdShadeConnectionSourceInfo. mod describes the
operation that should be applied to the list of connections. By
default the new connection will replace any existing connections, but
it can add to the list of connections to represent multiple input
connections.
true if a connection was created successfully. false if this
input or source is invalid.
This method does not verify the connectability of the shading
attribute to the source. Clients must invoke CanConnect() themselves
to ensure compatibility.
The source shading attribute is created if it doesn’t exist already.
UsdShadeConnectableAPI::ConnectToSource

Parameters

source (ConnectionSourceInfo) – 
mod (ConnectionModification) – 

ConnectToSource(source, sourceName, sourceType, typeName) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 
typeName (ValueTypeName) – 

ConnectToSource(sourcePath) -> bool
Authors a connection for this Input to the source at the given path.
UsdShadeConnectableAPI::ConnectToSource

Parameters
sourcePath (Path) – 

ConnectToSource(sourceInput) -> bool
Connects this Input to the given input, sourceInput .
UsdShadeConnectableAPI::ConnectToSource

Parameters
sourceInput (Input) – 

ConnectToSource(sourceOutput) -> bool
Connects this Input to the given output, sourceOutput .
UsdShadeConnectableAPI::ConnectToSource

Parameters
sourceOutput (Output) – 

DisconnectSource(sourceAttr) → bool
Disconnect source for this Input.
If sourceAttr is valid, only a connection to the specified
attribute is disconnected, otherwise all connections are removed.
UsdShadeConnectableAPI::DisconnectSource

Parameters
sourceAttr (Attribute) – 

Get(value, time) → bool
Convenience wrapper for the templated UsdAttribute::Get() .

Parameters

value (T) – 
time (TimeCode) – 

Get(value, time) -> bool
Convenience wrapper for VtValue version of UsdAttribute::Get() .

Parameters

value (VtValue) – 
time (TimeCode) – 

GetAttr() → Attribute
Explicit UsdAttribute extractor.

GetBaseName() → str
Returns the name of the input.
We call this the base name since it strips off the”inputs:”namespace
prefix from the attribute name, and returns it.

GetConnectability() → str
Returns the connectability of the Input.
SetConnectability()

GetConnectedSource(source, sourceName, sourceType) → bool
Deprecated

Parameters

source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 

GetConnectedSources(invalidSourcePaths) → list[SourceInfo]
Finds the valid sources of connections for the Input.
invalidSourcePaths is an optional output parameter to collect the
invalid source paths that have not been reported in the returned
vector.
Returns a vector of UsdShadeConnectionSourceInfo structs with
information about each upsteam attribute. If the vector is empty,
there have been no valid connections.
A valid connection requires the existence of the source attribute and
also requires that the source prim is UsdShadeConnectableAPI
compatible.
The python wrapping returns a tuple with the valid connections first,
followed by the invalid source paths.
UsdShadeConnectableAPI::GetConnectedSources

Parameters
invalidSourcePaths (list[SdfPath]) – 

GetDisplayGroup() → str
Get the displayGroup metadata for this Input, i.e.
hint for the location and nesting of the attribute.
UsdProperty::GetDisplayGroup() , UsdProperty::GetNestedDisplayGroup()

GetDocumentation() → str
Get documentation string for this Input.
UsdObject::GetDocumentation()

GetFullName() → str
Get the name of the attribute associated with the Input.

GetPrim() → Prim
Get the prim that the input belongs to.

GetRawConnectedSourcePaths(sourcePaths) → bool
Deprecated
Returns the”raw”(authored) connected source paths for this Input.
UsdShadeConnectableAPI::GetRawConnectedSourcePaths

Parameters
sourcePaths (list[SdfPath]) – 

GetRenderType() → str
Return this Input’s specialized renderType, or an empty token if none
was authored.
SetRenderType()

GetSdrMetadata() → NdrTokenMap
Returns this Input’s composed”sdrMetadata”dictionary as a NdrTokenMap.

GetSdrMetadataByKey(key) → str
Returns the value corresponding to key in the composed
sdrMetadata dictionary.

Parameters
key (str) – 

GetTypeName() → ValueTypeName
Get the”scene description”value type name of the attribute associated
with the Input.

GetValueProducingAttribute(attrType) → Attribute
Deprecated
in favor of calling GetValueProducingAttributes

Parameters
attrType (AttributeType) – 

GetValueProducingAttributes(shaderOutputsOnly) → list[UsdShadeAttribute]
Find what is connected to this Input recursively.
UsdShadeUtils::GetValueProducingAttributes

Parameters
shaderOutputsOnly (bool) – 

HasConnectedSource() → bool
Returns true if and only if this Input is currently connected to a
valid (defined) source.
UsdShadeConnectableAPI::HasConnectedSource

HasRenderType() → bool
Return true if a renderType has been specified for this Input.
SetRenderType()

HasSdrMetadata() → bool
Returns true if the Input has a non-empty
composed”sdrMetadata”dictionary value.

HasSdrMetadataByKey(key) → bool
Returns true if there is a value corresponding to the given key in
the composed”sdrMetadata”dictionary.

Parameters
key (str) – 

static IsInput()
classmethod IsInput(attr) -> bool
Test whether a given UsdAttribute represents a valid Input, which
implies that creating a UsdShadeInput from the attribute will succeed.
Success implies that attr.IsDefined() is true.

Parameters
attr (Attribute) – 

static IsInterfaceInputName()
classmethod IsInterfaceInputName(name) -> bool
Test if this name has a namespace that indicates it could be an input.

Parameters
name (str) – 

IsSourceConnectionFromBaseMaterial() → bool
Returns true if the connection to this Input’s source, as returned by
GetConnectedSource() , is authored across a specializes arc, which is
used to denote a base material.
UsdShadeConnectableAPI::IsSourceConnectionFromBaseMaterial

Set(value, time) → bool
Set a value for the Input at time .

Parameters

value (VtValue) – 
time (TimeCode) – 

Set(value, time) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.
Set a value of the Input at time .

Parameters

value (T) – 
time (TimeCode) – 

SetConnectability(connectability) → bool
Set the connectability of the Input.
In certain shading data models, there is a need to distinguish which
inputs can vary over a surface from those that must be
uniform. This is accomplished in UsdShade by limiting the
connectability of the input. This is done by setting
the”connectability”metadata on the associated attribute.
Connectability of an Input can be set to UsdShadeTokens->full or
UsdShadeTokens->interfaceOnly.

full implies that the Input can be connected to any other
Input or Output.
interfaceOnly implies that the Input can only be connected to
a NodeGraph Input (which represents an interface override, not a
render-time dataflow connection), or another Input whose
connectability is also”interfaceOnly”.
The default connectability of an input is UsdShadeTokens->full.

SetConnectability()

Parameters
connectability (str) – 

SetConnectedSources(sourceInfos) → bool
Connects this Input to the given sources, sourceInfos .
UsdShadeConnectableAPI::SetConnectedSources

Parameters
sourceInfos (list[ConnectionSourceInfo]) – 

SetDisplayGroup(displayGroup) → bool
Set the displayGroup metadata for this Input, i.e.
hinting for the location and nesting of the attribute.
Note for an input representing a nested SdrShaderProperty, its
expected to have the scope delimited by a”:”.
UsdProperty::SetDisplayGroup() , UsdProperty::SetNestedDisplayGroup()
SdrShaderProperty::GetPage()

Parameters
displayGroup (str) – 

SetDocumentation(docs) → bool
Set documentation string for this Input.
UsdObject::SetDocumentation()

Parameters
docs (str) – 

SetRenderType(renderType) → bool
Specify an alternative, renderer-specific type to use when
emitting/translating this Input, rather than translating based on its
GetTypeName()
For example, we set the renderType to”struct”for Inputs that are of
renderman custom struct types.
true on success.

Parameters
renderType (str) – 

SetSdrMetadata(sdrMetadata) → None
Authors the given sdrMetadata value on this Input at the current
EditTarget.

Parameters
sdrMetadata (NdrTokenMap) – 

SetSdrMetadataByKey(key, value) → None
Sets the value corresponding to key to the given string value
, in the Input’s”sdrMetadata”dictionary at the current EditTarget.

Parameters

key (str) – 
value (str) – 

class pxr.UsdShade.Material
A Material provides a container into which multiple”render targets”can
add data that defines a”shading material”for a renderer. Typically
this consists of one or more UsdRelationship properties that target
other prims of type Shader - though a target/client is free to add
any data that is suitable. We strongly advise that all targets
adopt the convention that all properties be prefixed with a namespace
that identifies the target, e.g.”rel ri:surface =</Shaders/mySurf>”.
In the UsdShading model, geometry expresses a binding to a single
Material or to a set of Materials partitioned by UsdGeomSubsets
defined beneath the geometry; it is legal to bind a Material at the
root (or other sub-prim) of a model, and then bind a different
Material to individual gprims, but the meaning of inheritance
and”ancestral overriding”of Material bindings is left to each render-
target to determine. Since UsdGeom has no concept of shading, we
provide the API for binding and unbinding geometry on the API schema
UsdShadeMaterialBindingAPI.
The entire power of USD VariantSets and all the other composition
operators can leveraged when encoding shading variation.
UsdShadeMaterial provides facilities for a particular way of
building”Material variants”in which neither the identity of the
Materials themselves nor the geometry Material-bindings need to change
- instead we vary the targeted networks, interface values, and even
parameter values within a single variantSet.  See Authoring Material
Variations for more details.
UsdShade requires that all of the shaders that”belong”to the Material
live under the Material in namespace. This supports powerful, easy
reuse of Materials, because it allows us to reference a Material
from one asset (the asset might be a module of Materials) into
another asset: USD references compose all descendant prims of the
reference target into the referencer’s namespace, which means that all
of the referenced Material’s shader networks will come along with the
Material. When referenced in this way, Materials can also be
instanced, for ease of deduplication and compactness. Finally,
Material encapsulation also allows us to specialize child materials
from parent materials.
For any described attribute Fallback Value or Allowed Values
below that are text/tokens, the actual token is published and defined
in UsdShadeTokens. So to set an attribute to the value”rightHanded”,
use UsdShadeTokens->rightHanded as the value.
Methods:

ClearBaseMaterial()
Clear the base Material of this Material.

ComputeDisplacementSource(renderContext, ...)
Deprecated

ComputeSurfaceSource(renderContext, ...)
Deprecated

ComputeVolumeSource(renderContext, ...)
Deprecated

CreateDisplacementAttr(defaultValue, ...)
See GetDisplacementAttr() , and also Create vs Get Property Methods for when to use Get vs Create.

CreateDisplacementOutput(renderContext)
Creates and returns the"displacement"output on this material for the specified renderContext .

CreateMasterMaterialVariant
classmethod CreateMasterMaterialVariant(masterPrim, MaterialPrims, masterVariantSetName) -> bool

CreateSurfaceAttr(defaultValue, writeSparsely)
See GetSurfaceAttr() , and also Create vs Get Property Methods for when to use Get vs Create.

CreateSurfaceOutput(renderContext)
Creates and returns the"surface"output on this material for the specified renderContext .

CreateVolumeAttr(defaultValue, writeSparsely)
See GetVolumeAttr() , and also Create vs Get Property Methods for when to use Get vs Create.

CreateVolumeOutput(renderContext)
Creates and returns the"volume"output on this material for the specified renderContext .

Define
classmethod Define(stage, path) -> Material

Get
classmethod Get(stage, path) -> Material

GetBaseMaterial()
Get the path to the base Material of this Material.

GetBaseMaterialPath()
Get the base Material of this Material.

GetDisplacementAttr()
Represents the universal"displacement"output terminal of a material.

GetDisplacementOutput(renderContext)
Returns the"displacement"output of this material for the specified renderContext.

GetDisplacementOutputs()
Returns the"displacement"outputs of this material for all available renderContexts.

GetEditContextForVariant(...)
Helper function for configuring a UsdStage 's UsdEditTarget to author Material variations.

GetMaterialVariant()
Return a UsdVariantSet object for interacting with the Material variant variantSet.

GetSchemaAttributeNames
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]

GetSurfaceAttr()
Represents the universal"surface"output terminal of a material.

GetSurfaceOutput(renderContext)
Returns the"surface"output of this material for the specified renderContext .

GetSurfaceOutputs()
Returns the"surface"outputs of this material for all available renderContexts.

GetVolumeAttr()
Represents the universal"volume"output terminal of a material.

GetVolumeOutput(renderContext)
Returns the"volume"output of this material for the specified renderContext.

GetVolumeOutputs()
Returns the"volume"outputs of this material for all available renderContexts.

HasBaseMaterial()

SetBaseMaterial(baseMaterial)
Set the base Material of this Material.

SetBaseMaterialPath(baseMaterialPath)
Set the path to the base Material of this Material.

ClearBaseMaterial() → None
Clear the base Material of this Material.

ComputeDisplacementSource(renderContext, sourceName, sourceType) → Shader
Deprecated
Use the form that takes a TfTokenVector or renderContexts

Parameters

renderContext (str) – 
sourceName (str) – 
sourceType (AttributeType) – 

ComputeDisplacementSource(contextVector, sourceName, sourceType) -> Shader
Computes the resolved”displacement”output source for the given
contextVector .
Using the earliest renderContext in the contextVector that produces a
valid Shader object.
If a”displacement”output corresponding to each of the renderContexts
does not exist or is not connected to a valid source, then this
checks the universal displacement output.
Returns an empty Shader object if there is no valid displacement
output source for any of the renderContexts in the contextVector .
The python version of this method returns a tuple containing three
elements (the source displacement shader, sourceName, sourceType).

Parameters

contextVector (list[TfToken]) – 
sourceName (str) – 
sourceType (AttributeType) – 

ComputeSurfaceSource(renderContext, sourceName, sourceType) → Shader
Deprecated
Use the form that takes a TfTokenVector or renderContexts.

Parameters

renderContext (str) – 
sourceName (str) – 
sourceType (AttributeType) – 

ComputeSurfaceSource(contextVector, sourceName, sourceType) -> Shader
Computes the resolved”surface”output source for the given
contextVector .
Using the earliest renderContext in the contextVector that produces a
valid Shader object.
If a”surface”output corresponding to each of the renderContexts does
not exist or is not connected to a valid source, then this checks
the universal surface output.
Returns an empty Shader object if there is no valid surface output
source for any of the renderContexts in the contextVector . The
python version of this method returns a tuple containing three
elements (the source surface shader, sourceName, sourceType).

Parameters

contextVector (list[TfToken]) – 
sourceName (str) – 
sourceType (AttributeType) – 

ComputeVolumeSource(renderContext, sourceName, sourceType) → Shader
Deprecated
Use the form that takes a TfTokenVector or renderContexts

Parameters

renderContext (str) – 
sourceName (str) – 
sourceType (AttributeType) – 

ComputeVolumeSource(contextVector, sourceName, sourceType) -> Shader
Computes the resolved”volume”output source for the given
contextVector .
Using the earliest renderContext in the contextVector that produces a
valid Shader object.
If a”volume”output corresponding to each of the renderContexts does
not exist or is not connected to a valid source, then this checks
the universal volume output.
Returns an empty Shader object if there is no valid volume output
output source for any of the renderContexts in the contextVector .
The python version of this method returns a tuple containing three
elements (the source volume shader, sourceName, sourceType).

Parameters

contextVector (list[TfToken]) – 
sourceName (str) – 
sourceType (AttributeType) – 

CreateDisplacementAttr(defaultValue, writeSparsely) → Attribute
See GetDisplacementAttr() , 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) – 

CreateDisplacementOutput(renderContext) → Output
Creates and returns the”displacement”output on this material for the
specified renderContext .
If the output already exists on the material, it is returned and no
authoring is performed. The returned output will always have the
requested renderContext.

Parameters
renderContext (str) – 

static CreateMasterMaterialVariant()
classmethod CreateMasterMaterialVariant(masterPrim, MaterialPrims, masterVariantSetName) -> bool
Create a variantSet on masterPrim that will set the
MaterialVariant on each of the given MaterialPrims.
The variantSet, whose name can be specified with
masterVariantSetName and defaults to the same MaterialVariant name
created on Materials by GetEditContextForVariant() , will have the
same variants as the Materials, and each Master variant will set every
MaterialPrims' MaterialVariant selection to the same variant as
the master. Thus, it allows all Materials to be switched with a single
variant selection, on masterPrim .
If masterPrim is an ancestor of any given member of
MaterialPrims , then we will author variant selections directly on
the MaterialPrims. However, it is often preferable to create a master
MaterialVariant in a separately rooted tree from the MaterialPrims, so
that it can be layered more strongly on top of the Materials.
Therefore, for any MaterialPrim in a different tree than masterPrim,
we will create”overs”as children of masterPrim that recreate the path
to the MaterialPrim, substituting masterPrim’s full path for the
MaterialPrim’s root path component.
Upon successful completion, the new variantSet we created on
masterPrim will have its variant selection authored to
the”last”variant (determined lexicographically). It is up to the
calling client to either UsdVariantSet::ClearVariantSelection() on
masterPrim , or set the selection to the desired default setting.
Return true on success. It is an error if any of Materials
have a different set of variants for the MaterialVariant than the
others.

Parameters

masterPrim (Prim) – 
MaterialPrims (list[Prim]) – 
masterVariantSetName (str) – 

CreateSurfaceAttr(defaultValue, writeSparsely) → Attribute
See GetSurfaceAttr() , 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) – 

CreateSurfaceOutput(renderContext) → Output
Creates and returns the”surface”output on this material for the
specified renderContext .
If the output already exists on the material, it is returned and no
authoring is performed. The returned output will always have the
requested renderContext.

Parameters
renderContext (str) – 

CreateVolumeAttr(defaultValue, writeSparsely) → Attribute
See GetVolumeAttr() , 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) – 

CreateVolumeOutput(renderContext) → Output
Creates and returns the”volume”output on this material for the
specified renderContext .
If the output already exists on the material, it is returned and no
authoring is performed. The returned output will always have the
requested renderContext.

Parameters
renderContext (str) – 

static Define()
classmethod Define(stage, path) -> Material
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) -> Material
Return a UsdShadeMaterial 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:
UsdShadeMaterial(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetBaseMaterial() → Material
Get the path to the base Material of this Material.
If there is no base Material, an empty Material is returned

GetBaseMaterialPath() → Path
Get the base Material of this Material.
If there is no base Material, an empty path is returned

GetDisplacementAttr() → Attribute
Represents the universal”displacement”output terminal of a material.
Declaration
token outputs:displacement
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token

GetDisplacementOutput(renderContext) → Output
Returns the”displacement”output of this material for the specified
renderContext.
The returned output will always have the requested renderContext.
An invalid output is returned if an output corresponding to the
requested specific-renderContext does not exist.
UsdShadeMaterial::ComputeDisplacementSource()

Parameters
renderContext (str) – 

GetDisplacementOutputs() → list[Output]
Returns the”displacement”outputs of this material for all available
renderContexts.
The returned vector will include all authored”displacement”outputs
with the universal renderContext output first, if present. Outputs
are returned regardless of whether they are connected to a valid
source.

GetEditContextForVariant(MaterialVariantName, layer) → tuple[Stage, EditTarget]
Helper function for configuring a UsdStage ‘s UsdEditTarget to author
Material variations.
Takes care of creating the Material variantSet and specified variant,
if necessary.
Let’s assume that we are authoring Materials into the Stage’s current
UsdEditTarget, and that we are iterating over the variations of a
UsdShadeMaterial clothMaterial, and currVariant is the variant we
are processing (e.g.”denim”).
In C++, then, we would use the following pattern:
{
    UsdEditContext ctxt(clothMaterial.GetEditContextForVariant(currVariant));

    // All USD mutation of the UsdStage on which clothMaterial sits will
    // now go "inside" the currVariant of the "MaterialVariant" variantSet
}

In python, the pattern is:
with clothMaterial.GetEditContextForVariant(currVariant):
    # Now sending mutations to currVariant

If layer is specified, then we will use it, rather than the
stage’s current UsdEditTarget ‘s layer as the destination layer for
the edit context we are building. If layer does not actually
contribute to the Material prim’s definition, any editing will have no
effect on this Material.
Note: As just stated, using this method involves authoring a
selection for the MaterialVariant in the stage’s current EditTarget.
When client is done authoring variations on this prim, they will
likely want to either UsdVariantSet::SetVariantSelection() to the
appropriate default selection, or possibly
UsdVariantSet::ClearVariantSelection() on the
UsdShadeMaterial::GetMaterialVariant() UsdVariantSet.
UsdVariantSet::GetVariantEditContext()

Parameters

MaterialVariantName (str) – 
layer (Layer) – 

GetMaterialVariant() → VariantSet
Return a UsdVariantSet object for interacting with the Material
variant variantSet.

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) – 

GetSurfaceAttr() → Attribute
Represents the universal”surface”output terminal of a material.
Declaration
token outputs:surface
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token

GetSurfaceOutput(renderContext) → Output
Returns the”surface”output of this material for the specified
renderContext .
The returned output will always have the requested renderContext.
An invalid output is returned if an output corresponding to the
requested specific-renderContext does not exist.
UsdShadeMaterial::ComputeSurfaceSource()

Parameters
renderContext (str) – 

GetSurfaceOutputs() → list[Output]
Returns the”surface”outputs of this material for all available
renderContexts.
The returned vector will include all authored”surface”outputs with the
universal renderContext output first, if present. Outputs are
returned regardless of whether they are connected to a valid source.

GetVolumeAttr() → Attribute
Represents the universal”volume”output terminal of a material.
Declaration
token outputs:volume
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token

GetVolumeOutput(renderContext) → Output
Returns the”volume”output of this material for the specified
renderContext.
The returned output will always have the requested renderContext.
An invalid output is returned if an output corresponding to the
requested specific-renderContext does not exist.
UsdShadeMaterial::ComputeVolumeSource()

Parameters
renderContext (str) – 

GetVolumeOutputs() → list[Output]
Returns the”volume”outputs of this material for all available
renderContexts.
The returned vector will include all authored”volume”outputs with the
universal renderContext output first, if present. Outputs are
returned regardless of whether they are connected to a valid source.

HasBaseMaterial() → bool

SetBaseMaterial(baseMaterial) → None
Set the base Material of this Material.
An empty Material is equivalent to clearing the base Material.

Parameters
baseMaterial (Material) – 

SetBaseMaterialPath(baseMaterialPath) → None
Set the path to the base Material of this Material.
An empty path is equivalent to clearing the base Material.

Parameters
baseMaterialPath (Path) – 

class pxr.UsdShade.MaterialBindingAPI
UsdShadeMaterialBindingAPI is an API schema that provides an interface
for binding materials to prims or collections of prims (represented by
UsdCollectionAPI objects).
In the USD shading model, each renderable gprim computes a single
resolved Material that will be used to shade the gprim
(exceptions, of course, for gprims that possess UsdGeomSubsets, as
each subset can be shaded by a different Material). A gprim and each
of its ancestor prims can possess, through the MaterialBindingAPI,
both a direct binding to a Material, and any number of
collection-based bindings to Materials; each binding can be
generic or declared for a particular purpose, and given a specific
binding strength. It is the process of”material resolution”(see
UsdShadeMaterialBindingAPI_MaterialResolution) that examines all of
these bindings, and selects the one Material that best matches the
client’s needs.
The intent of purpose is that each gprim should be able to resolve
a Material for any given purpose, which implies it can have
differently bound materials for different purposes. There are two
special values of purpose defined in UsdShade, although the API
fully supports specifying arbitrary values for it, for the sake of
extensibility:

UsdShadeTokens->full : to be used when the purpose of the
render is entirely to visualize the truest representation of a scene,
considering all lighting and material information, at highest
fidelity.
UsdShadeTokens->preview : to be used when the render is in
service of a goal other than a high fidelity”full”render (such as
scene manipulation, modeling, or realtime playback). Latency and speed
are generally of greater concern for preview renders, therefore
preview materials are generally designed to be”lighterweight”compared
to full materials.
A binding can also have no specific purpose at all, in which case, it
is considered to be the fallback or all-purpose binding (denoted by
the empty-valued token UsdShadeTokens->allPurpose).

The purpose of a material binding is encoded in the name of the
binding relationship.

In the case of a direct binding, the allPurpose binding is
represented by the relationship named “material:binding”. Special-
purpose direct bindings are represented by relationships named
“material:binding: *purpose*. A direct binding relationship must
have a single target path that points to a UsdShadeMaterial.
In the case of a collection-based binding, the allPurpose
binding is represented by a relationship
named”material:binding:collection:<i>bindingName</i>”, where
bindingName establishes an identity for the binding that is unique
on the prim. Attempting to establish two collection bindings of the
same name on the same prim will result in the first binding simply
being overridden. A special-purpose collection-based binding is
represented by a relationship
named”material:binding:collection:<i>purpose:bindingName</i>”. A
collection-based binding relationship must have exacly two targets,
one of which should be a collection-path (see ef
UsdCollectionAPI::GetCollectionPath() ) and the other should point to
a UsdShadeMaterial. In the future, we may allow a single
collection binding to target multiple collections, if we can establish
a reasonable round-tripping pattern for applications that only allow a
single collection to be associated with each Material.

Note: Both bindingName and purpose must be non-namespaced
tokens. This allows us to know the role of a binding relationship
simply from the number of tokens in it.

Two tokens : the fallback,”all purpose”, direct binding,
material:binding
Three tokens : a purpose-restricted, direct, fallback
binding, e.g. material:binding:preview
Four tokens : an all-purpose, collection-based binding, e.g.
material:binding:collection:metalBits
Five tokens : a purpose-restricted, collection-based binding,
e.g. material:binding:collection:full:metalBits

A binding-strength value is used to specify whether a binding
authored on a prim should be weaker or stronger than bindings that
appear lower in namespace. We encode the binding strength with as
token-valued metadata ‘bindMaterialAs’ for future flexibility,
even though for now, there are only two possible values:
UsdShadeTokens->weakerThanDescendants and
UsdShadeTokens->strongerThanDescendants. When binding-strength is
not authored (i.e. empty) on a binding-relationship, the default
behavior matches UsdShadeTokens->weakerThanDescendants.
If a material binding relationship is a built-in property defined as
part of a typed prim’s schema, a fallback value should not be provided
for it. This is because the”material resolution”algorithm only
conisders authored properties.
Classes:

CollectionBinding

DirectBinding

Methods:

AddPrimToBindingCollection(prim, ...)
Adds the specified prim to the collection targeted by the binding relationship corresponding to given bindingName and materialPurpose .

Apply
classmethod Apply(prim) -> MaterialBindingAPI

Bind(material, bindingStrength, materialPurpose)
Authors a direct binding to the given material on this prim.

CanApply
classmethod CanApply(prim, whyNot) -> bool

CanContainPropertyName
classmethod CanContainPropertyName(name) -> bool

ComputeBoundMaterial(bindingsCache, ...)
Computes the resolved bound material for this prim, for the given material purpose.

ComputeBoundMaterials
classmethod ComputeBoundMaterials(prims, materialPurpose, bindingRels) -> list[Material]

CreateMaterialBindSubset(subsetName, ...)
Creates a GeomSubset named subsetName with element type, elementType and familyName materialBind **below this prim.**

Get
classmethod Get(stage, path) -> MaterialBindingAPI

GetCollectionBindingRel(bindingName, ...)
Returns the collection-based material-binding relationship with the given bindingName and materialPurpose on this prim.

GetCollectionBindingRels(materialPurpose)
Returns the list of collection-based material binding relationships on this prim for the given material purpose, materialPurpose .

GetCollectionBindings(materialPurpose)
Returns all the collection-based bindings on this prim for the given material purpose.

GetDirectBinding(materialPurpose)
Computes and returns the direct binding for the given material purpose on this prim.

GetDirectBindingRel(materialPurpose)
Returns the direct material-binding relationship on this prim for the given material purpose.

GetMaterialBindSubsets()
Returns all the existing GeomSubsets with familyName=UsdShadeTokens->materialBind below this prim.

GetMaterialBindSubsetsFamilyType()
Returns the familyType of the family of"materialBind"GeomSubsets on this prim.

GetMaterialBindingStrength
classmethod GetMaterialBindingStrength(bindingRel) -> str

GetMaterialPurposes
classmethod GetMaterialPurposes() -> list[TfToken]

GetResolvedTargetPathFromBindingRel
classmethod GetResolvedTargetPathFromBindingRel(bindingRel) -> Path

GetSchemaAttributeNames
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]

RemovePrimFromBindingCollection(prim, ...)
Removes the specified prim from the collection targeted by the binding relationship corresponding to given bindingName and materialPurpose .

SetMaterialBindSubsetsFamilyType(familyType)
Author the familyType of the"materialBind"family of GeomSubsets on this prim.

SetMaterialBindingStrength
classmethod SetMaterialBindingStrength(bindingRel, bindingStrength) -> bool

UnbindAllBindings()
Unbinds all direct and collection-based bindings on this prim.

UnbindCollectionBinding(bindingName, ...)
Unbinds the collection-based binding with the given bindingName , for the given materialPurpose on this prim.

UnbindDirectBinding(materialPurpose)
Unbinds the direct binding for the given material purpose ( materialPurpose ) on this prim.

class CollectionBinding
Methods:

GetBindingRel

GetCollection

GetCollectionPath

GetMaterial

GetMaterialPath

IsCollectionBindingRel

IsValid

GetBindingRel()

GetCollection()

GetCollectionPath()

GetMaterial()

GetMaterialPath()

static IsCollectionBindingRel()

IsValid()

class DirectBinding
Methods:

GetBindingRel

GetMaterial

GetMaterialPath

GetMaterialPurpose

GetBindingRel()

GetMaterial()

GetMaterialPath()

GetMaterialPurpose()

AddPrimToBindingCollection(prim, bindingName, materialPurpose) → bool
Adds the specified prim to the collection targeted by the binding
relationship corresponding to given bindingName and
materialPurpose .
If the collection-binding relationship doesn’t exist or if the
targeted collection already includes the prim , then this does
nothing and returns true.
If the targeted collection does not include prim (or excludes it
explicitly), then this modifies the collection by adding the prim to
it (by invoking UsdCollectionAPI::AddPrim()).

Parameters

prim (Prim) – 
bindingName (str) – 
materialPurpose (str) – 

static Apply()
classmethod Apply(prim) -> MaterialBindingAPI
Applies this single-apply API schema to the given prim .
This information is stored by adding”MaterialBindingAPI”to the token-
valued, listOp metadata apiSchemas on the prim.
A valid UsdShadeMaterialBindingAPI object is returned upon success. An
invalid (or empty) UsdShadeMaterialBindingAPI 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) – 

Bind(material, bindingStrength, materialPurpose) → bool
Authors a direct binding to the given material on this prim.
If bindingStrength is UsdShadeTokens->fallbackStrength, the value
UsdShadeTokens->weakerThanDescendants is authored sparsely. To stamp
out the bindingStrength value explicitly, clients can pass in
UsdShadeTokens->weakerThanDescendants or
UsdShadeTokens->strongerThanDescendants directly.
If materialPurpose is specified and isn’t equal to
UsdShadeTokens->allPurpose, the binding only applies to the specified
material purpose.
Note that UsdShadeMaterialBindingAPI is a SingleAppliedAPI schema
which when applied updates the prim definition accordingly. This
information on the prim definition is helpful in multiple queries and
more performant. Hence its recommended to call
UsdShadeMaterialBindingAPI::Apply() when Binding a material.
Returns true on success, false otherwise.

Parameters

material (Material) – 
bindingStrength (str) – 
materialPurpose (str) – 

Bind(collection, material, bindingName, bindingStrength, materialPurpose) -> bool
Authors a collection-based binding, which binds the given material
to the given collection on this prim.
bindingName establishes an identity for the binding that is unique
on the prim. Attempting to establish two collection bindings of the
same name on the same prim will result in the first binding simply
being overridden. If bindingName is empty, it is set to the base-
name of the collection being bound (which is the collection-name with
any namespaces stripped out). If there are multiple collections with
the same base-name being bound at the same prim, clients should pass
in a unique binding name per binding, in order to preserve all
bindings. The binding name used in constructing the collection-binding
relationship name shoud not contain namespaces. Hence, a coding error
is issued and no binding is authored if the provided value of
bindingName is non-empty and contains namespaces.
If bindingStrength is UsdShadeTokens->fallbackStrength, the
value UsdShadeTokens->weakerThanDescendants is authored sparsely, i.e.
only when there is an existing binding with a different
bindingStrength. To stamp out the bindingStrength value explicitly,
clients can pass in UsdShadeTokens->weakerThanDescendants or
UsdShadeTokens->strongerThanDescendants directly.
If materialPurpose is specified and isn’t equal to
UsdShadeTokens->allPurpose, the binding only applies to the specified
material purpose.
Note that UsdShadeMaterialBindingAPI is a SingleAppliedAPI schema
which when applied updates the prim definition accordingly. This
information on the prim definition is helpful in multiple queries and
more performant. Hence its recommended to call
UsdShadeMaterialBindingAPI::Apply() when Binding a material.
Returns true on success, false otherwise.

Parameters

collection (CollectionAPI) – 
material (Material) – 
bindingName (str) – 
bindingStrength (str) – 
materialPurpose (str) – 

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 CanContainPropertyName()
classmethod CanContainPropertyName(name) -> bool
Test whether a given name contains the”material:binding:”prefix.

Parameters
name (str) – 

ComputeBoundMaterial(bindingsCache, collectionQueryCache, materialPurpose, bindingRel) → Material
Computes the resolved bound material for this prim, for the given
material purpose.
This overload of ComputeBoundMaterial makes use of the BindingsCache (
bindingsCache ) and CollectionQueryCache (
collectionQueryCache ) that are passed in, to avoid redundant
binding computations and computations of MembershipQuery objects for
collections. It would be beneficial to make use of these when
resolving bindings for a tree of prims. These caches are populated
lazily as more and more bindings are resolved.
When the goal is to compute the bound material for a range (or list)
of prims, it is recommended to use this version of
ComputeBoundMaterial() . Here’s how you could compute the bindings of
a range of prims efficiently in C++:
std::vector<std::pair<UsdPrim, UsdShadeMaterial> primBindings;
UsdShadeMaterialBindingAPI::BindingsCache bindingsCache;
UsdShadeMaterialBindingAPI::CollectionQueryCache collQueryCache;

for (auto prim : UsdPrimRange(rootPrim)) {
    UsdShadeMaterial boundMaterial =
          UsdShadeMaterialBindingAPI(prim).ComputeBoundMaterial(
           & bindingsCache,  & collQueryCache);
    if (boundMaterial) {
        primBindings.emplace_back({prim, boundMaterial});
    }
}

If bindingRel is not null, then it is set to the”winning”binding
relationship.
Note the resolved bound material is considered valid if the target
path of the binding relationship is a valid non-empty prim path. This
makes sure winning binding relationship and the bound material remain
consistent consistent irrespective of the presence/absence of prim at
material path. For ascenario where ComputeBoundMaterial returns a
invalid UsdShadeMaterial with a valid winning bindingRel, clients can
use the  static method
UsdShadeMaterialBindingAPI::GetResolvedTargetPathFromBindingRel to get
the path of the resolved target identified by the winning bindingRel.
See Bound Material Resolution for details on the material resolution
process.
The python version of this method returns a tuple containing the bound
material and the”winning”binding relationship.

Parameters

bindingsCache (BindingsCache) – 
collectionQueryCache (CollectionQueryCache) – 
materialPurpose (str) – 
bindingRel (Relationship) – 

ComputeBoundMaterial(materialPurpose, bindingRel) -> Material
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.
Computes the resolved bound material for this prim, for the given
material purpose.
This overload does not utilize cached MembershipQuery object. However,
it only computes the MembershipQuery of every collection that bound in
the ancestor chain at most once.
If bindingRel is not null, then it is set to the winning binding
relationship.
See Bound Material Resolution for details on the material resolution
process.
The python version of this method returns a tuple containing the bound
material and the”winning”binding relationship.

Parameters

materialPurpose (str) – 
bindingRel (Relationship) – 

static ComputeBoundMaterials()
classmethod ComputeBoundMaterials(prims, materialPurpose, bindingRels) -> list[Material]
Static API for efficiently and concurrently computing the resolved
material bindings for a vector of UsdPrims, prims for the given
materialPurpose .
The size of the returned vector always matches the size of the input
vector, prims . If a prim is not bound to any material, an invalid
or empty UsdShadeMaterial is returned at the index corresponding to
it.
If the pointer bindingRels points to a valid vector, then it is
populated with the set of all”winning”binding relationships.
The python version of this method returns a tuple containing two lists
- the bound materials and the corresponding”winning”binding
relationships.

Parameters

prims (list[Prim]) – 
materialPurpose (str) – 
bindingRels (list[Relationship]) – 

CreateMaterialBindSubset(subsetName, indices, elementType) → Subset
Creates a GeomSubset named subsetName with element type,
elementType and familyName materialBind **below this prim.**
If a GeomSubset named subsetName already exists, then
its”familyName”is updated to be UsdShadeTokens->materialBind and its
indices (at default timeCode) are updated with the provided
indices value before returning.
This method forces the familyType of the”materialBind”family of
subsets to UsdGeomTokens->nonOverlapping if it’s unset or explicitly
set to UsdGeomTokens->unrestricted.
The default value elementType is UsdGeomTokens->face, as we expect
materials to be bound most often to subsets of faces on meshes.

Parameters

subsetName (str) – 
indices (IntArray) – 
elementType (str) – 

static Get()
classmethod Get(stage, path) -> MaterialBindingAPI
Return a UsdShadeMaterialBindingAPI 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:
UsdShadeMaterialBindingAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetCollectionBindingRel(bindingName, materialPurpose) → Relationship
Returns the collection-based material-binding relationship with the
given bindingName and materialPurpose on this prim.
For info on bindingName , see UsdShadeMaterialBindingAPI::Bind() .
The material purpose of the relationship that’s returned will match
the specified materialPurpose .

Parameters

bindingName (str) – 
materialPurpose (str) – 

GetCollectionBindingRels(materialPurpose) → list[Relationship]
Returns the list of collection-based material binding relationships on
this prim for the given material purpose, materialPurpose .
The returned list of binding relationships will be in native property
order. See UsdPrim::GetPropertyOrder() , UsdPrim::SetPropertyOrder() .
Bindings that appear earlier in the property order are considered to
be stronger than the ones that come later. See rule #6 in
UsdShadeMaterialBindingAPI_MaterialResolution.

Parameters
materialPurpose (str) – 

GetCollectionBindings(materialPurpose) → list[CollectionBinding]
Returns all the collection-based bindings on this prim for the given
material purpose.
The returned CollectionBinding objects always have the specified
materialPurpose (i.e. the all-purpose binding is not returned if a
special purpose binding is requested).
If one or more collection based bindings are to prims that are not
Materials, this does not generate an error, but the corresponding
Material(s) will be invalid (i.e. evaluate to false).
The python version of this API returns a tuple containing the vector
of CollectionBinding objects and the corresponding vector of binding
relationships.
The returned list of collection-bindings will be in native property
order of the associated binding relationships. See
UsdPrim::GetPropertyOrder() , UsdPrim::SetPropertyOrder() . Binding
relationships that come earlier in the list are considered to be
stronger than the ones that come later. See rule #6 in
UsdShadeMaterialBindingAPI_MaterialResolution.

Parameters
materialPurpose (str) – 

GetDirectBinding(materialPurpose) → DirectBinding
Computes and returns the direct binding for the given material purpose
on this prim.
The returned binding always has the specified materialPurpose
(i.e. the all-purpose binding is not returned if a special purpose
binding is requested).
If the direct binding is to a prim that is not a Material, this does
not generate an error, but the returned Material will be invalid (i.e.
evaluate to false).

Parameters
materialPurpose (str) – 

GetDirectBindingRel(materialPurpose) → Relationship
Returns the direct material-binding relationship on this prim for the
given material purpose.
The material purpose of the relationship that’s returned will match
the specified materialPurpose .

Parameters
materialPurpose (str) – 

GetMaterialBindSubsets() → list[Subset]
Returns all the existing GeomSubsets with
familyName=UsdShadeTokens->materialBind below this prim.

GetMaterialBindSubsetsFamilyType() → str
Returns the familyType of the family of”materialBind”GeomSubsets on
this prim.
By default, materialBind subsets have familyType=”nonOverlapping”, but
they can also be tagged as a”partition”, using
SetMaterialBindFaceSubsetsFamilyType().
UsdGeomSubset::GetFamilyNameAttr

static GetMaterialBindingStrength()
classmethod GetMaterialBindingStrength(bindingRel) -> str
Resolves the’bindMaterialAs’token-valued metadata on the given binding
relationship and returns it.
If the resolved value is empty, this returns the fallback value
UsdShadeTokens->weakerThanDescendants.
UsdShadeMaterialBindingAPI::SetMaterialBindingStrength()

Parameters
bindingRel (Relationship) – 

static GetMaterialPurposes()
classmethod GetMaterialPurposes() -> list[TfToken]
Returns a vector of the possible values for the’material purpose’.

static GetResolvedTargetPathFromBindingRel()
classmethod GetResolvedTargetPathFromBindingRel(bindingRel) -> Path
returns the path of the resolved target identified by bindingRel .

Parameters
bindingRel (Relationship) – 

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) – 

RemovePrimFromBindingCollection(prim, bindingName, materialPurpose) → bool
Removes the specified prim from the collection targeted by the
binding relationship corresponding to given bindingName and
materialPurpose .
If the collection-binding relationship doesn’t exist or if the
targeted collection does not include the prim , then this does
nothing and returns true.
If the targeted collection includes prim , then this modifies the
collection by removing the prim from it (by invoking
UsdCollectionAPI::RemovePrim()). This method can be used in
conjunction with the Unbind*() methods (if desired) to guarantee
that a prim has no resolved material binding.

Parameters

prim (Prim) – 
bindingName (str) – 
materialPurpose (str) – 

SetMaterialBindSubsetsFamilyType(familyType) → bool
Author the familyType of the”materialBind”family of GeomSubsets on
this prim.
The default familyType is UsdGeomTokens->nonOverlapping *. It can
be set to *UsdGeomTokens->partition to indicate that the entire
imageable prim is included in the union of all
the”materialBind”subsets. The family type should never be set to
UsdGeomTokens->unrestricted, since it is invalid for a single piece of
geometry (in this case, a subset) to be bound to more than one
material. Hence, a coding error is issued if familyType is
UsdGeomTokens->unrestricted.**
**
UsdGeomSubset::SetFamilyType**

Parameters
familyType (str) – 

static SetMaterialBindingStrength()
classmethod SetMaterialBindingStrength(bindingRel, bindingStrength) -> bool
Sets the’bindMaterialAs’token-valued metadata on the given binding
relationship.
If bindingStrength is UsdShadeTokens->fallbackStrength, the
value UsdShadeTokens->weakerThanDescendants is authored sparsely, i.e.
only when there is a different existing bindingStrength value. To
stamp out the bindingStrength value explicitly, clients can pass in
UsdShadeTokens->weakerThanDescendants or
UsdShadeTokens->strongerThanDescendants directly. Returns true on
success, false otherwise.
UsdShadeMaterialBindingAPI::GetMaterialBindingStrength()

Parameters

bindingRel (Relationship) – 
bindingStrength (str) – 

UnbindAllBindings() → bool
Unbinds all direct and collection-based bindings on this prim.

UnbindCollectionBinding(bindingName, materialPurpose) → bool
Unbinds the collection-based binding with the given bindingName ,
for the given materialPurpose on this prim.
It accomplishes this by blocking the targets of the associated binding
relationship in the current edit target.
If a binding was created without specifying a bindingName , then
the correct bindingName to use for unbinding is the instance name
of the targetted collection.

Parameters

bindingName (str) – 
materialPurpose (str) – 

UnbindDirectBinding(materialPurpose) → bool
Unbinds the direct binding for the given material purpose (
materialPurpose ) on this prim.
It accomplishes this by blocking the targets of the binding
relationship in the current edit target.

Parameters
materialPurpose (str) – 

class pxr.UsdShade.NodeDefAPI
UsdShadeNodeDefAPI is an API schema that provides attributes for a
prim to select a corresponding Shader Node Definition (“Sdr Node”), as
well as to look up a runtime entry for that shader node in the form of
an SdrShaderNode.
UsdShadeNodeDefAPI is intended to be a pre-applied API schema for any
prim type that wants to refer to the SdrRegistry for further
implementation details about the behavior of that prim. The primary
use in UsdShade itself is as UsdShadeShader, which is a basis for
material shading networks (UsdShadeMaterial), but this is intended to
be used in other domains that also use the Sdr node mechanism.
This schema provides properties that allow a prim to identify an
external node definition, either by a direct identifier key into the
SdrRegistry (info:id), an asset to be parsed by a suitable
NdrParserPlugin (info:sourceAsset), or an inline source code that must
also be parsed (info:sourceCode); as well as a selector attribute to
determine which specifier is active (info:implementationSource).
For any described attribute Fallback Value or Allowed Values
below that are text/tokens, the actual token is published and defined
in UsdShadeTokens. So to set an attribute to the value”rightHanded”,
use UsdShadeTokens->rightHanded as the value.
Methods:

Apply
classmethod Apply(prim) -> NodeDefAPI

CanApply
classmethod CanApply(prim, whyNot) -> bool

CreateIdAttr(defaultValue, writeSparsely)
See GetIdAttr() , and also Create vs Get Property Methods for when to use Get vs Create.

CreateImplementationSourceAttr(defaultValue, ...)
See GetImplementationSourceAttr() , and also Create vs Get Property Methods for when to use Get vs Create.

Get
classmethod Get(stage, path) -> NodeDefAPI

GetIdAttr()
The id is an identifier for the type or purpose of the shader.

GetImplementationSource()
Reads the value of info:implementationSource attribute and returns a token identifying the attribute that must be consulted to identify the shader's source program.

GetImplementationSourceAttr()
Specifies the attribute that should be consulted to get the shader's implementation or its source code.

GetSchemaAttributeNames
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]

GetShaderId(id)
Fetches the shader's ID value from the info:id attribute, if the shader's info:implementationSource is id.

GetShaderNodeForSourceType(sourceType)
This method attempts to ensure that there is a ShaderNode in the shader registry (i.e.

GetSourceAsset(sourceAsset, sourceType)
Fetches the shader's source asset value for the specified sourceType value from the info: *sourceType*: sourceAsset attribute, if the shader's info:implementationSource is sourceAsset.

GetSourceAssetSubIdentifier(subIdentifier, ...)
Fetches the shader's sub-identifier for the source asset with the specified sourceType value from the info: *sourceType*: sourceAsset:subIdentifier attribute, if the shader's info: implementationSource is sourceAsset.

GetSourceCode(sourceCode, sourceType)
Fetches the shader's source code for the specified sourceType value by reading the info: *sourceType*: sourceCode attribute, if the shader's info:implementationSource is sourceCode.

SetShaderId(id)
Sets the shader's ID value.

SetSourceAsset(sourceAsset, sourceType)
Sets the shader's source-asset path value to sourceAsset for the given source type, sourceType .

SetSourceAssetSubIdentifier(subIdentifier, ...)
Set a sub-identifier to be used with a source asset of the given source type.

SetSourceCode(sourceCode, sourceType)
Sets the shader's source-code value to sourceCode for the given source type, sourceType .

static Apply()
classmethod Apply(prim) -> NodeDefAPI
Applies this single-apply API schema to the given prim .
This information is stored by adding”NodeDefAPI”to the token-valued,
listOp metadata apiSchemas on the prim.
A valid UsdShadeNodeDefAPI object is returned upon success. An invalid
(or empty) UsdShadeNodeDefAPI 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) – 

CreateIdAttr(defaultValue, writeSparsely) → Attribute
See GetIdAttr() , 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) – 

CreateImplementationSourceAttr(defaultValue, writeSparsely) → Attribute
See GetImplementationSourceAttr() , 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) -> NodeDefAPI
Return a UsdShadeNodeDefAPI 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:
UsdShadeNodeDefAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetIdAttr() → Attribute
The id is an identifier for the type or purpose of the shader.
E.g.: Texture or FractalFloat. The use of this id will depend on the
render target: some will turn it into an actual shader path, some will
use it to generate shader source code dynamically.
SetShaderId()
Declaration
uniform token info:id
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
Variability
SdfVariabilityUniform

GetImplementationSource() → str
Reads the value of info:implementationSource attribute and returns a
token identifying the attribute that must be consulted to identify the
shader’s source program.
This returns

id, to indicate that the”info:id”attribute must be consulted.
sourceAsset to indicate that the asset-
valued”info:{sourceType}:sourceAsset”attribute associated with the
desired sourceType should be consulted to locate the asset with
the shader’s source.
sourceCode to indicate that the string-
valued”info:{sourceType}:sourceCode”attribute associated with the
desired sourceType should be read to get shader’s source.

This issues a warning and returns id if the
info:implementationSource attribute has an invalid value.
{sourceType} above is a place holder for a token that identifies the
type of shader source or its implementation. For example: osl, glslfx,
riCpp etc. This allows a shader to specify different sourceAsset (or
sourceCode) values for different sourceTypes. The sourceType tokens
usually correspond to the sourceType value of the NdrParserPlugin
that’s used to parse the shader source (NdrParserPlugin::SourceType).
When sourceType is empty, the corresponding sourceAsset or sourceCode
is considered to be”universal”(or fallback), which is represented by
the empty-valued token UsdShadeTokens->universalSourceType. When the
sourceAsset (or sourceCode) corresponding to a specific, requested
sourceType is unavailable, the universal sourceAsset (or sourceCode)
is returned by GetSourceAsset (and GetSourceCode} API, if present.
GetShaderId()
GetSourceAsset()
GetSourceCode()

GetImplementationSourceAttr() → Attribute
Specifies the attribute that should be consulted to get the shader’s
implementation or its source code.

If set to”id”, the”info:id”attribute’s value is used to determine
the shader source from the shader registry.
If set to”sourceAsset”, the resolved value of
the”info:sourceAsset”attribute corresponding to the desired
implementation (or source-type) is used to locate the shader source. A
source asset file may also specify multiple shader definitions, so
there is an optional attribute”info:sourceAsset:subIdentifier”whose
value should be used to indicate a particular shader definition from a
source asset file.
If set to”sourceCode”, the value of”info:sourceCode”attribute
corresponding to the desired implementation (or source type) is used
as the shader source.

Declaration
uniform token info:implementationSource ="id"
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
Variability
SdfVariabilityUniform
Allowed Values
id, sourceAsset, sourceCode

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) – 

GetShaderId(id) → bool
Fetches the shader’s ID value from the info:id attribute, if the
shader’s info:implementationSource is id.
Returns true if the shader’s implementation source is id and
the value was fetched properly into id . Returns false otherwise.
GetImplementationSource()

Parameters
id (str) – 

GetShaderNodeForSourceType(sourceType) → ShaderNode
This method attempts to ensure that there is a ShaderNode in the
shader registry (i.e.
SdrRegistry) representing this shader for the given sourceType .
It may return a null pointer if none could be found or created.

Parameters
sourceType (str) – 

GetSourceAsset(sourceAsset, sourceType) → bool
Fetches the shader’s source asset value for the specified
sourceType value from the info: *sourceType*: sourceAsset
attribute, if the shader’s info:implementationSource is
sourceAsset.
If the sourceAsset attribute corresponding to the requested
sourceType isn’t present on the shader, then the universal
fallback sourceAsset attribute, i.e. info:sourceAsset is
consulted, if present, to get the source asset path.
Returns true if the shader’s implementation source is
sourceAsset and the source asset path value was fetched
successfully into sourceAsset . Returns false otherwise.
GetImplementationSource()

Parameters

sourceAsset (AssetPath) – 
sourceType (str) – 

GetSourceAssetSubIdentifier(subIdentifier, sourceType) → bool
Fetches the shader’s sub-identifier for the source asset with the
specified sourceType value from the info: *sourceType*:
sourceAsset:subIdentifier attribute, if the shader’s info:
implementationSource is sourceAsset.
If the subIdentifier attribute corresponding to the requested
sourceType isn’t present on the shader, then the universal
fallback sub-identifier attribute, i.e. info:sourceAsset:
subIdentifier is consulted, if present, to get the sub-identifier
name.
Returns true if the shader’s implementation source is
sourceAsset and the sub-identifier for the given source type was
fetched successfully into subIdentifier . Returns false otherwise.

Parameters

subIdentifier (str) – 
sourceType (str) – 

GetSourceCode(sourceCode, sourceType) → bool
Fetches the shader’s source code for the specified sourceType
value by reading the info: *sourceType*: sourceCode attribute, if
the shader’s info:implementationSource is sourceCode.
If the sourceCode attribute corresponding to the requested
sourceType isn’t present on the shader, then the universal or
fallback sourceCode attribute (i.e. info:sourceCode) is consulted,
if present, to get the source code.
Returns true if the shader’s implementation source is
sourceCode and the source code string was fetched successfully
into sourceCode . Returns false otherwise.
GetImplementationSource()

Parameters

sourceCode (str) – 
sourceType (str) – 

SetShaderId(id) → bool
Sets the shader’s ID value.
This also sets the info:implementationSource attribute on the shader
to UsdShadeTokens->id, if the existing value is different.

Parameters
id (str) – 

SetSourceAsset(sourceAsset, sourceType) → bool
Sets the shader’s source-asset path value to sourceAsset for the
given source type, sourceType .
This also sets the info:implementationSource attribute on the shader
to UsdShadeTokens->sourceAsset.

Parameters

sourceAsset (AssetPath) – 
sourceType (str) – 

SetSourceAssetSubIdentifier(subIdentifier, sourceType) → bool
Set a sub-identifier to be used with a source asset of the given
source type.
This sets the info: *sourceType*: sourceAsset:subIdentifier.
This also sets the info:implementationSource attribute on the shader
to UsdShadeTokens->sourceAsset

Parameters

subIdentifier (str) – 
sourceType (str) – 

SetSourceCode(sourceCode, sourceType) → bool
Sets the shader’s source-code value to sourceCode for the given
source type, sourceType .
This also sets the info:implementationSource attribute on the shader
to UsdShadeTokens->sourceCode.

Parameters

sourceCode (str) – 
sourceType (str) – 

class pxr.UsdShade.NodeGraph
A node-graph is a container for shading nodes, as well as other node-
graphs. It has a public input interface and provides a list of public
outputs.
Node Graph Interfaces
One of the most important functions of a node-graph is to host
the”interface”with which clients of already-built shading networks
will interact. Please see Interface Inputs for a detailed explanation
of what the interface provides, and how to construct and use it, to
effectively share/instance shader networks.
Node Graph Outputs
These behave like outputs on a shader and are typically connected to
an output on a shader inside the node-graph.
Methods:

ComputeInterfaceInputConsumersMap(...)
Walks the namespace subtree below the node-graph and computes a map containing the list of all inputs on the node-graph and the associated vector of consumers of their values.

ComputeOutputSource(outputName, sourceName, ...)
Deprecated

ConnectableAPI()
Contructs and returns a UsdShadeConnectableAPI object with this node- graph.

CreateInput(name, typeName)
Create an Input which can either have a value or can be connected.

CreateOutput(name, typeName)
Create an output which can either have a value or can be connected.

Define
classmethod Define(stage, path) -> NodeGraph

Get
classmethod Get(stage, path) -> NodeGraph

GetInput(name)
Return the requested input if it exists.

GetInputs(onlyAuthored)
Returns all inputs present on the node-graph.

GetInterfaceInputs()
Returns all the"Interface Inputs"of the node-graph.

GetOutput(name)
Return the requested output if it exists.

GetOutputs(onlyAuthored)
Outputs are represented by attributes in the"outputs:"namespace.

GetSchemaAttributeNames
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]

ComputeInterfaceInputConsumersMap(computeTransitiveConsumers) → InterfaceInputConsumersMap
Walks the namespace subtree below the node-graph and computes a map
containing the list of all inputs on the node-graph and the associated
vector of consumers of their values.
The consumers can be inputs on shaders within the node-graph or on
nested node-graphs).
If computeTransitiveConsumers is true, then value consumers
belonging to node-graphs are resolved transitively to compute the
transitive mapping from inputs on the node-graph to inputs on shaders
inside the material. Note that inputs on node-graphs that don’t have
value consumers will continue to be included in the result.
This API is provided for use by DCC’s that want to present node-graph
interface / shader connections in the opposite direction than they are
encoded in USD.

Parameters
computeTransitiveConsumers (bool) – 

ComputeOutputSource(outputName, sourceName, sourceType) → Shader
Deprecated
in favor of GetValueProducingAttributes on UsdShadeOutput Resolves the
connection source of the requested output, identified by
outputName to a shader output.
sourceName is an output parameter that is set to the name of the
resolved output, if the node-graph output is connected to a valid
shader source.
sourceType is an output parameter that is set to the type of the
resolved output, if the node-graph output is connected to a valid
shader source.
Returns a valid shader object if the specified output exists and is
connected to one. Return an empty shader object otherwise. The python
version of this method returns a tuple containing three elements (the
source shader, sourceName, sourceType).

Parameters

outputName (str) – 
sourceName (str) – 
sourceType (AttributeType) – 

ConnectableAPI() → ConnectableAPI
Contructs and returns a UsdShadeConnectableAPI object with this node-
graph.
Note that most tasks can be accomplished without explicitly
constructing a UsdShadeConnectable API, since connection-related API
such as UsdShadeConnectableAPI::ConnectToSource() are static methods,
and UsdShadeNodeGraph will auto-convert to a UsdShadeConnectableAPI
when passed to functions that want to act generically on a connectable
UsdShadeConnectableAPI object.

CreateInput(name, typeName) → Input
Create an Input which can either have a value or can be connected.
The attribute representing the input is created in
the”inputs:”namespace.

Parameters

name (str) – 
typeName (ValueTypeName) – 

CreateOutput(name, typeName) → Output
Create an output which can either have a value or can be connected.
The attribute representing the output is created in
the”outputs:”namespace.

Parameters

name (str) – 
typeName (ValueTypeName) – 

static Define()
classmethod Define(stage, path) -> NodeGraph
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) -> NodeGraph
Return a UsdShadeNodeGraph 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:
UsdShadeNodeGraph(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetInput(name) → Input
Return the requested input if it exists.

Parameters
name (str) – 

GetInputs(onlyAuthored) → list[Input]
Returns all inputs present on the node-graph.
These 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.

Parameters
onlyAuthored (bool) – 

GetInterfaceInputs() → list[Input]
Returns all the”Interface Inputs”of the node-graph.
This is the same as GetInputs() , but is provided as a convenience, to
allow clients to distinguish between inputs on shaders vs. interface-
inputs on node-graphs.

GetOutput(name) → Output
Return the requested output if it exists.

Parameters
name (str) – 

GetOutputs(onlyAuthored) → list[Output]
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.

Parameters
onlyAuthored (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) – 

class pxr.UsdShade.Output
This class encapsulates a shader or node-graph output, which is a
connectable attribute representing a typed, externally computed value.
Methods:

CanConnect(source)
Determines whether this Output can be connected to the given source attribute, which can be an input or an output.

ClearSdrMetadata()
Clears any"sdrMetadata"value authored on the Output in the current EditTarget.

ClearSdrMetadataByKey(key)
Clears the entry corresponding to the given key in the"sdrMetadata"dictionary authored in the current EditTarget.

ClearSource()
Deprecated

ClearSources()
Clears sources for this Output in the current UsdEditTarget.

ConnectToSource(source, mod)
Authors a connection for this Output.

DisconnectSource(sourceAttr)
Disconnect source for this Output.

GetAttr()
Explicit UsdAttribute extractor.

GetBaseName()
Returns the name of the output.

GetConnectedSource(source, sourceName, ...)
Deprecated

GetConnectedSources(invalidSourcePaths)
Finds the valid sources of connections for the Output.

GetFullName()
Get the name of the attribute associated with the output.

GetPrim()
Get the prim that the output belongs to.

GetRawConnectedSourcePaths(sourcePaths)
Deprecated

GetRenderType()
Return this output's specialized renderType, or an empty token if none was authored.

GetSdrMetadata()
Returns this Output's composed"sdrMetadata"dictionary as a NdrTokenMap.

GetSdrMetadataByKey(key)
Returns the value corresponding to key in the composed sdrMetadata dictionary.

GetTypeName()
Get the"scene description"value type name of the attribute associated with the output.

GetValueProducingAttributes(shaderOutputsOnly)
Find what is connected to this Output recursively.

HasConnectedSource()
Returns true if and only if this Output is currently connected to a valid (defined) source.

HasRenderType()
Return true if a renderType has been specified for this output.

HasSdrMetadata()
Returns true if the Output has a non-empty composed"sdrMetadata"dictionary value.

HasSdrMetadataByKey(key)
Returns true if there is a value corresponding to the given key in the composed"sdrMetadata"dictionary.

IsOutput
classmethod IsOutput(attr) -> bool

IsSourceConnectionFromBaseMaterial()
Returns true if the connection to this Output's source, as returned by GetConnectedSource() , is authored across a specializes arc, which is used to denote a base material.

Set(value, time)
Set a value for the output.

SetConnectedSources(sourceInfos)
Connects this Output to the given sources, sourceInfos .

SetRenderType(renderType)
Specify an alternative, renderer-specific type to use when emitting/translating this output, rather than translating based on its GetTypeName()

SetSdrMetadata(sdrMetadata)
Authors the given sdrMetadata value on this Output at the current EditTarget.

SetSdrMetadataByKey(key, value)
Sets the value corresponding to key to the given string value , in the Output's"sdrMetadata"dictionary at the current EditTarget.

CanConnect(source) → bool
Determines whether this Output can be connected to the given source
attribute, which can be an input or an output.
An output is considered to be connectable only if it belongs to a
node-graph. Shader outputs are not connectable.
UsdShadeConnectableAPI::CanConnect

Parameters
source (Attribute) – 

CanConnect(sourceInput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
sourceInput (Input) – 

CanConnect(sourceOutput) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters
sourceOutput (Output) – 

ClearSdrMetadata() → None
Clears any”sdrMetadata”value authored on the Output in the current
EditTarget.

ClearSdrMetadataByKey(key) → None
Clears the entry corresponding to the given key in
the”sdrMetadata”dictionary authored in the current EditTarget.

Parameters
key (str) – 

ClearSource() → bool
Deprecated

ClearSources() → bool
Clears sources for this Output in the current UsdEditTarget.
Most of the time, what you probably want is DisconnectSource() rather
than this function.
UsdShadeConnectableAPI::ClearSources

ConnectToSource(source, mod) → bool
Authors a connection for this Output.
source is a struct that describes the upstream source attribute
with all the information necessary to make a connection. See the
documentation for UsdShadeConnectionSourceInfo. mod describes the
operation that should be applied to the list of connections. By
default the new connection will replace any existing connections, but
it can add to the list of connections to represent multiple input
connections.
true if a connection was created successfully. false if
shadingAttr or source is invalid.
This method does not verify the connectability of the shading
attribute to the source. Clients must invoke CanConnect() themselves
to ensure compatibility.
The source shading attribute is created if it doesn’t exist already.
UsdShadeConnectableAPI::ConnectToSource

Parameters

source (ConnectionSourceInfo) – 
mod (ConnectionModification) – 

ConnectToSource(source, sourceName, sourceType, typeName) -> bool
Deprecated
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 
typeName (ValueTypeName) – 

ConnectToSource(sourcePath) -> bool
Authors a connection for this Output to the source at the given path.
UsdShadeConnectableAPI::ConnectToSource

Parameters
sourcePath (Path) – 

ConnectToSource(sourceInput) -> bool
Connects this Output to the given input, sourceInput .
UsdShadeConnectableAPI::ConnectToSource

Parameters
sourceInput (Input) – 

ConnectToSource(sourceOutput) -> bool
Connects this Output to the given output, sourceOutput .
UsdShadeConnectableAPI::ConnectToSource

Parameters
sourceOutput (Output) – 

DisconnectSource(sourceAttr) → bool
Disconnect source for this Output.
If sourceAttr is valid, only a connection to the specified
attribute is disconnected, otherwise all connections are removed.
UsdShadeConnectableAPI::DisconnectSource

Parameters
sourceAttr (Attribute) – 

GetAttr() → Attribute
Explicit UsdAttribute extractor.

GetBaseName() → str
Returns the name of the output.
We call this the base name since it strips off the”outputs:”namespace
prefix from the attribute name, and returns it.

GetConnectedSource(source, sourceName, sourceType) → bool
Deprecated
Please use GetConnectedSources instead

Parameters

source (ConnectableAPI) – 
sourceName (str) – 
sourceType (AttributeType) – 

GetConnectedSources(invalidSourcePaths) → list[SourceInfo]
Finds the valid sources of connections for the Output.
invalidSourcePaths is an optional output parameter to collect the
invalid source paths that have not been reported in the returned
vector.
Returns a vector of UsdShadeConnectionSourceInfo structs with
information about each upsteam attribute. If the vector is empty,
there have been no valid connections.
A valid connection requires the existence of the source attribute and
also requires that the source prim is UsdShadeConnectableAPI
compatible.
The python wrapping returns a tuple with the valid connections first,
followed by the invalid source paths.
UsdShadeConnectableAPI::GetConnectedSources

Parameters
invalidSourcePaths (list[SdfPath]) – 

GetFullName() → str
Get the name of the attribute associated with the output.

GetPrim() → Prim
Get the prim that the output belongs to.

GetRawConnectedSourcePaths(sourcePaths) → bool
Deprecated
Returns the”raw”(authored) connected source paths for this Output.
UsdShadeConnectableAPI::GetRawConnectedSourcePaths

Parameters
sourcePaths (list[SdfPath]) – 

GetRenderType() → str
Return this output’s specialized renderType, or an empty token if none
was authored.
SetRenderType()

GetSdrMetadata() → NdrTokenMap
Returns this Output’s composed”sdrMetadata”dictionary as a
NdrTokenMap.

GetSdrMetadataByKey(key) → str
Returns the value corresponding to key in the composed
sdrMetadata dictionary.

Parameters
key (str) – 

GetTypeName() → ValueTypeName
Get the”scene description”value type name of the attribute associated
with the output.

GetValueProducingAttributes(shaderOutputsOnly) → list[UsdShadeAttribute]
Find what is connected to this Output recursively.
UsdShadeUtils::GetValueProducingAttributes

Parameters
shaderOutputsOnly (bool) – 

HasConnectedSource() → bool
Returns true if and only if this Output is currently connected to a
valid (defined) source.
UsdShadeConnectableAPI::HasConnectedSource

HasRenderType() → bool
Return true if a renderType has been specified for this output.
SetRenderType()

HasSdrMetadata() → bool
Returns true if the Output has a non-empty
composed”sdrMetadata”dictionary value.

HasSdrMetadataByKey(key) → bool
Returns true if there is a value corresponding to the given key in
the composed”sdrMetadata”dictionary.

Parameters
key (str) – 

static IsOutput()
classmethod IsOutput(attr) -> bool
Test whether a given UsdAttribute represents a valid Output, which
implies that creating a UsdShadeOutput from the attribute will
succeed.
Success implies that attr.IsDefined() is true.

Parameters
attr (Attribute) – 

IsSourceConnectionFromBaseMaterial() → bool
Returns true if the connection to this Output’s source, as returned by
GetConnectedSource() , is authored across a specializes arc, which is
used to denote a base material.
UsdShadeConnectableAPI::IsSourceConnectionFromBaseMaterial

Set(value, time) → bool
Set a value for the output.
It’s unusual to be setting a value on an output since it represents an
externally computed value. The Set API is provided here just for the
sake of completeness and uniformity with other property schema.

Parameters

value (VtValue) – 
time (TimeCode) – 

Set(value, time) -> bool
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.
Set the attribute value of the Output at time .

Parameters

value (T) – 
time (TimeCode) – 

SetConnectedSources(sourceInfos) → bool
Connects this Output to the given sources, sourceInfos .
UsdShadeConnectableAPI::SetConnectedSources

Parameters
sourceInfos (list[ConnectionSourceInfo]) – 

SetRenderType(renderType) → bool
Specify an alternative, renderer-specific type to use when
emitting/translating this output, rather than translating based on its
GetTypeName()
For example, we set the renderType to”struct”for outputs that are of
renderman custom struct types.
true on success

Parameters
renderType (str) – 

SetSdrMetadata(sdrMetadata) → None
Authors the given sdrMetadata value on this Output at the current
EditTarget.

Parameters
sdrMetadata (NdrTokenMap) – 

SetSdrMetadataByKey(key, value) → None
Sets the value corresponding to key to the given string value
, in the Output’s”sdrMetadata”dictionary at the current EditTarget.

Parameters

key (str) – 
value (str) – 

class pxr.UsdShade.Shader
Base class for all USD shaders. Shaders are the building blocks of
shading networks. While UsdShadeShader objects are not target
specific, each renderer or application target may derive its own
renderer-specific shader object types from this base, if needed.
Objects of this class generally represent a single shading object,
whether it exists in the target renderer or not. For example, a
texture, a fractal, or a mix node.
The UsdShadeNodeDefAPI provides attributes to uniquely identify the
type of this node. The id resolution into a renderable shader target
type of this node. The id resolution into a renderable shader target
is deferred to the consuming application.
The purpose of representing them in Usd is two-fold:

To represent, via”connections”the topology of the shading network
that must be reconstructed in the renderer. Facilities for authoring
and manipulating connections are encapsulated in the API schema
UsdShadeConnectableAPI.
To present a (partial or full) interface of typed input
parameters whose values can be set and overridden in Usd, to be
provided later at render-time as parameter values to the actual render
shader objects. Shader input parameters are encapsulated in the
property schema UsdShadeInput.

Methods:

ClearSdrMetadata()
Clears any"sdrMetadata"value authored on the shader in the current EditTarget.

ClearSdrMetadataByKey(key)
Clears the entry corresponding to the given key in the"sdrMetadata"dictionary authored in the current EditTarget.

ConnectableAPI()
Contructs and returns a UsdShadeConnectableAPI object with this shader.

CreateIdAttr(defaultValue, writeSparsely)
Forwards to UsdShadeNodeDefAPI(prim).

CreateImplementationSourceAttr(defaultValue, ...)
Forwards to UsdShadeNodeDefAPI(prim).

CreateInput(name, typeName)
Create an input which can either have a value or can be connected.

CreateOutput(name, typeName)
Create an output which can either have a value or can be connected.

Define
classmethod Define(stage, path) -> Shader

Get
classmethod Get(stage, path) -> Shader

GetIdAttr()
Forwards to UsdShadeNodeDefAPI(prim).

GetImplementationSource()
Forwards to UsdShadeNodeDefAPI(prim).

GetImplementationSourceAttr()
Forwards to UsdShadeNodeDefAPI(prim).

GetInput(name)
Return the requested input if it exists.

GetInputs(onlyAuthored)
Inputs are represented by attributes in the"inputs:"namespace.

GetOutput(name)
Return the requested output if it exists.

GetOutputs(onlyAuthored)
Outputs are represented by attributes in the"outputs:"namespace.

GetSchemaAttributeNames
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]

GetSdrMetadata()
Returns this shader's composed"sdrMetadata"dictionary as a NdrTokenMap.

GetSdrMetadataByKey(key)
Returns the value corresponding to key in the composed sdrMetadata dictionary.

GetShaderId(id)
Forwards to UsdShadeNodeDefAPI(prim).

GetShaderNodeForSourceType(sourceType)
Forwards to UsdShadeNodeDefAPI(prim).

GetSourceAsset(sourceAsset, sourceType)
Forwards to UsdShadeNodeDefAPI(prim).

GetSourceAssetSubIdentifier(subIdentifier, ...)
Forwards to UsdShadeNodeDefAPI(prim).

GetSourceCode(sourceCode, sourceType)
Forwards to UsdShadeNodeDefAPI(prim).

HasSdrMetadata()
Returns true if the shader has a non-empty composed"sdrMetadata"dictionary value.

HasSdrMetadataByKey(key)
Returns true if there is a value corresponding to the given key in the composed"sdrMetadata"dictionary.

SetSdrMetadata(sdrMetadata)
Authors the given sdrMetadata on this shader at the current EditTarget.

SetSdrMetadataByKey(key, value)
Sets the value corresponding to key to the given string value , in the shader's"sdrMetadata"dictionary at the current EditTarget.

SetShaderId(id)
Forwards to UsdShadeNodeDefAPI(prim).

SetSourceAsset(sourceAsset, sourceType)
Forwards to UsdShadeNodeDefAPI(prim).

SetSourceAssetSubIdentifier(subIdentifier, ...)
Forwards to UsdShadeNodeDefAPI(prim).

SetSourceCode(sourceCode, sourceType)
Forwards to UsdShadeNodeDefAPI(prim).

ClearSdrMetadata() → None
Clears any”sdrMetadata”value authored on the shader in the current
EditTarget.

ClearSdrMetadataByKey(key) → None
Clears the entry corresponding to the given key in
the”sdrMetadata”dictionary authored in the current EditTarget.

Parameters
key (str) – 

ConnectableAPI() → ConnectableAPI
Contructs and returns a UsdShadeConnectableAPI object with this
shader.
Note that most tasks can be accomplished without explicitly
constructing a UsdShadeConnectable API, since connection-related API
such as UsdShadeConnectableAPI::ConnectToSource() are static methods,
and UsdShadeShader will auto-convert to a UsdShadeConnectableAPI when
passed to functions that want to act generically on a connectable
UsdShadeConnectableAPI object.

CreateIdAttr(defaultValue, writeSparsely) → Attribute
Forwards to UsdShadeNodeDefAPI(prim).

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateImplementationSourceAttr(defaultValue, writeSparsely) → Attribute
Forwards to UsdShadeNodeDefAPI(prim).

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateInput(name, typeName) → Input
Create an input which can either have a value or can be connected.
The attribute representing the input is created in
the”inputs:”namespace. Inputs on both shaders and node-graphs are
connectable.

Parameters

name (str) – 
typeName (ValueTypeName) – 

CreateOutput(name, typeName) → Output
Create an output which can either have a value or can be connected.
The attribute representing the output is created in
the”outputs:”namespace. Outputs on a shader cannot be connected, as
their value is assumed to be computed externally.

Parameters

name (str) – 
typeName (ValueTypeName) – 

static Define()
classmethod Define(stage, path) -> Shader
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) -> Shader
Return a UsdShadeShader 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:
UsdShadeShader(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetIdAttr() → Attribute
Forwards to UsdShadeNodeDefAPI(prim).

GetImplementationSource() → str
Forwards to UsdShadeNodeDefAPI(prim).

GetImplementationSourceAttr() → Attribute
Forwards to UsdShadeNodeDefAPI(prim).

GetInput(name) → Input
Return the requested input if it exists.

Parameters
name (str) – 

GetInputs(onlyAuthored) → list[Input]
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.

Parameters
onlyAuthored (bool) – 

GetOutput(name) → Output
Return the requested output if it exists.

Parameters
name (str) – 

GetOutputs(onlyAuthored) → list[Output]
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.

Parameters
onlyAuthored (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) – 

GetSdrMetadata() → NdrTokenMap
Returns this shader’s composed”sdrMetadata”dictionary as a
NdrTokenMap.

GetSdrMetadataByKey(key) → str
Returns the value corresponding to key in the composed
sdrMetadata dictionary.

Parameters
key (str) – 

GetShaderId(id) → bool
Forwards to UsdShadeNodeDefAPI(prim).

Parameters
id (str) – 

GetShaderNodeForSourceType(sourceType) → ShaderNode
Forwards to UsdShadeNodeDefAPI(prim).

Parameters
sourceType (str) – 

GetSourceAsset(sourceAsset, sourceType) → bool
Forwards to UsdShadeNodeDefAPI(prim).

Parameters

sourceAsset (AssetPath) – 
sourceType (str) – 

GetSourceAssetSubIdentifier(subIdentifier, sourceType) → bool
Forwards to UsdShadeNodeDefAPI(prim).

Parameters

subIdentifier (str) – 
sourceType (str) – 

GetSourceCode(sourceCode, sourceType) → bool
Forwards to UsdShadeNodeDefAPI(prim).

Parameters

sourceCode (str) – 
sourceType (str) – 

HasSdrMetadata() → bool
Returns true if the shader has a non-empty
composed”sdrMetadata”dictionary value.

HasSdrMetadataByKey(key) → bool
Returns true if there is a value corresponding to the given key in
the composed”sdrMetadata”dictionary.

Parameters
key (str) – 

SetSdrMetadata(sdrMetadata) → None
Authors the given sdrMetadata on this shader at the current
EditTarget.

Parameters
sdrMetadata (NdrTokenMap) – 

SetSdrMetadataByKey(key, value) → None
Sets the value corresponding to key to the given string value
, in the shader’s”sdrMetadata”dictionary at the current EditTarget.

Parameters

key (str) – 
value (str) – 

SetShaderId(id) → bool
Forwards to UsdShadeNodeDefAPI(prim).

Parameters
id (str) – 

SetSourceAsset(sourceAsset, sourceType) → bool
Forwards to UsdShadeNodeDefAPI(prim).

Parameters

sourceAsset (AssetPath) – 
sourceType (str) – 

SetSourceAssetSubIdentifier(subIdentifier, sourceType) → bool
Forwards to UsdShadeNodeDefAPI(prim).

Parameters

subIdentifier (str) – 
sourceType (str) – 

SetSourceCode(sourceCode, sourceType) → bool
Forwards to UsdShadeNodeDefAPI(prim).

Parameters

sourceCode (str) – 
sourceType (str) – 

class pxr.UsdShade.ShaderDefParserPlugin
Parses shader definitions represented using USD scene description
using the schemas provided by UsdShade.
Methods:

GetDiscoveryTypes()
Returns the types of nodes that this plugin can parse.

GetSourceType()
Returns the source type that this parser operates on.

Parse(discoveryResult)
Takes the specified NdrNodeDiscoveryResult instance, which was a result of the discovery process, and generates a new NdrNode .

GetDiscoveryTypes() → NdrTokenVec
Returns the types of nodes that this plugin can parse.
“Type”here is the discovery type (in the case of files, this will
probably be the file extension, but in other systems will be data that
can be determined during discovery). This type should only be used to
match up a NdrNodeDiscoveryResult to its parser plugin; this value
is not exposed in the node’s API.

GetSourceType() → str
Returns the source type that this parser operates on.
A source type is the most general type for a node. The parser plugin
is responsible for parsing all discovery results that have the types
declared under GetDiscoveryTypes() , and those types are
collectively identified as one”source type”.

Parse(discoveryResult) → NdrNodeUnique
Takes the specified NdrNodeDiscoveryResult instance, which was a
result of the discovery process, and generates a new NdrNode .
The node’s name, source type, and family must match.

Parameters
discoveryResult (NodeDiscoveryResult) – 

class pxr.UsdShade.ShaderDefUtils
This class contains a set of utility functions used for populating the
shader registry with shaders definitions specified using UsdShade
schemas.
Methods:

GetNodeDiscoveryResults
classmethod GetNodeDiscoveryResults(shaderDef, sourceUri) -> NdrNodeDiscoveryResultVec

GetPrimvarNamesMetadataString
classmethod GetPrimvarNamesMetadataString(metadata, shaderDef) -> str

GetShaderProperties
classmethod GetShaderProperties(shaderDef) -> NdrPropertyUniquePtrVec

static GetNodeDiscoveryResults()
classmethod GetNodeDiscoveryResults(shaderDef, sourceUri) -> NdrNodeDiscoveryResultVec
Returns the list of NdrNodeDiscoveryResult objects that must be added
to the shader registry for the given shader shaderDef , assuming
it is found in a shader definition file found by an Ndr discovery
plugin.
To enable the shaderDef parser to find and parse this shader,
sourceUri should have the resolved path to the usd file containing
this shader prim.

Parameters

shaderDef (Shader) – 
sourceUri (str) – 

static GetPrimvarNamesMetadataString()
classmethod GetPrimvarNamesMetadataString(metadata, shaderDef) -> str
Collects all the names of valid primvar inputs of the given
metadata and the given shaderDef and returns the string used
to represent them in SdrShaderNode metadata.

Parameters

metadata (NdrTokenMap) – 
shaderDef (ConnectableAPI) – 

static GetShaderProperties()
classmethod GetShaderProperties(shaderDef) -> NdrPropertyUniquePtrVec
Gets all input and output properties of the given shaderDef and
translates them into NdrProperties that can be used as the properties
for an SdrShaderNode.

Parameters
shaderDef (ConnectableAPI) – 

class pxr.UsdShade.Tokens
Attributes:

allPurpose

bindMaterialAs

coordSys

displacement

fallbackStrength

full

id

infoId

infoImplementationSource

inputs

interfaceOnly

materialBind

materialBinding

materialBindingCollection

materialVariant

outputs

outputsDisplacement

outputsSurface

outputsVolume

preview

sdrMetadata

sourceAsset

sourceCode

strongerThanDescendants

subIdentifier

surface

universalRenderContext

universalSourceType

volume

weakerThanDescendants

allPurpose = ''

bindMaterialAs = 'bindMaterialAs'

coordSys = 'coordSys:'

displacement = 'displacement'

fallbackStrength = 'fallbackStrength'

full = 'full'

id = 'id'

infoId = 'info:id'

infoImplementationSource = 'info:implementationSource'

inputs = 'inputs:'

interfaceOnly = 'interfaceOnly'

materialBind = 'materialBind'

materialBinding = 'material:binding'

materialBindingCollection = 'material:binding:collection'

materialVariant = 'materialVariant'

outputs = 'outputs:'

outputsDisplacement = 'outputs:displacement'

outputsSurface = 'outputs:surface'

outputsVolume = 'outputs:volume'

preview = 'preview'

sdrMetadata = 'sdrMetadata'

sourceAsset = 'sourceAsset'

sourceCode = 'sourceCode'

strongerThanDescendants = 'strongerThanDescendants'

subIdentifier = 'subIdentifier'

surface = 'surface'

universalRenderContext = ''

universalSourceType = ''

volume = 'volume'

weakerThanDescendants = 'weakerThanDescendants'

class pxr.UsdShade.Utils
This class contains a set of utility functions used when authoring and
querying shading networks.
Methods:

GetBaseNameAndType
classmethod GetBaseNameAndType(fullName) -> tuple[str, AttributeType]

GetConnectedSourcePath
classmethod GetConnectedSourcePath(srcInfo) -> Path

GetFullName
classmethod GetFullName(baseName, type) -> str

GetPrefixForAttributeType
classmethod GetPrefixForAttributeType(sourceType) -> str

GetType
classmethod GetType(fullName) -> AttributeType

GetValueProducingAttributes
classmethod GetValueProducingAttributes(input, shaderOutputsOnly) -> list[UsdShadeAttribute]

static GetBaseNameAndType()
classmethod GetBaseNameAndType(fullName) -> tuple[str, AttributeType]
Given the full name of a shading attribute, returns it’s base name and
shading attribute type.

Parameters
fullName (str) – 

static GetConnectedSourcePath()
classmethod GetConnectedSourcePath(srcInfo) -> Path
For a valid UsdShadeConnectionSourceInfo, return the complete path to
the source property; otherwise the empty path.

Parameters
srcInfo (ConnectionSourceInfo) – 

static GetFullName()
classmethod GetFullName(baseName, type) -> str
Returns the full shading attribute name given the basename and the
shading attribute type.
baseName is the name of the input or output on the shading node.
type is the UsdShadeAttributeType of the shading attribute.

Parameters

baseName (str) – 
type (AttributeType) – 

static GetPrefixForAttributeType()
classmethod GetPrefixForAttributeType(sourceType) -> str
Returns the namespace prefix of the USD attribute associated with the
given shading attribute type.

Parameters
sourceType (AttributeType) – 

static GetType()
classmethod GetType(fullName) -> AttributeType
Given the full name of a shading attribute, returns its shading
attribute type.

Parameters
fullName (str) – 

static GetValueProducingAttributes()
classmethod GetValueProducingAttributes(input, shaderOutputsOnly) -> list[UsdShadeAttribute]
Find what is connected to an Input or Output recursively.
GetValueProducingAttributes implements the UsdShade connectivity rules
described in Connection Resolution Utilities.
When tracing connections within networks that contain containers like
UsdShadeNodeGraph nodes, the actual output(s) or value(s) at the end
of an input or output might be multiple connections removed. The
methods below resolves this across multiple physical connections.
An UsdShadeInput is getting its value from one of these sources:

If the input is not connected the UsdAttribute for this input is
returned, but only if it has an authored value. The input attribute
itself carries the value for this input.
If the input is connected we follow the connection(s) until we
reach a valid output of a UsdShadeShader node or if we reach a valid
UsdShadeInput attribute of a UsdShadeNodeGraph or UsdShadeMaterial
that has an authored value.

An UsdShadeOutput on a container can get its value from the same type
of sources as a UsdShadeInput on either a UsdShadeShader or
UsdShadeNodeGraph. Outputs on non-containers (UsdShadeShaders) cannot
be connected.
This function returns a vector of UsdAttributes. The vector is empty
if no valid attribute was found. The type of each attribute can be
determined with the UsdShadeUtils::GetType function.
If shaderOutputsOnly is true, it will only report attributes that
are outputs of non-containers (UsdShadeShaders). This is a bit faster
and what is need when determining the connections for Material
terminals.
This will return the last attribute along the connection chain that
has an authored value, which might not be the last attribute in the
chain itself.
When the network contains multi-connections, this function can return
multiple attributes for a single input or output. The list of
attributes is build by a depth-first search, following the underlying
connection paths in order. The list can contain both UsdShadeOutput
and UsdShadeInput attributes. It is up to the caller to decide how to
process such a mixture.

Parameters

input (Input) – 
shaderOutputsOnly (bool) – 

GetValueProducingAttributes(output, shaderOutputsOnly) -> list[UsdShadeAttribute]
This is an overloaded member function, provided for convenience. It
differs from the above function only in what argument(s) it accepts.

Parameters

output (Output) – 
shaderOutputsOnly (bool) – 

© Copyright 2019-2023, NVIDIA.
      Last updated on Nov 14, 2023.