UsdLux.md

UsdLux module — pxr-usd-api 105.1 documentation

pxr-usd-api

 »
Modules »
UsdLux module

 

# UsdLux module

Summary: The UsdLux module provides a representation for lights and related components that are common to many graphics environments.

Classes:

BoundableLightBase
Base class for intrinsic lights that are boundable.

CylinderLight
Light emitted outward from a cylinder.

DiskLight
Light emitted from one side of a circular disk.

DistantLight
Light emitted from a distant source along the -Z axis.

DomeLight
Light emitted inward from a distant external environment, such as a sky or IBL light probe.

GeometryLight
Deprecated

LightAPI
API schema that imparts the quality of being a light onto a prim.

LightFilter
A light filter modifies the effect of a light.

LightListAPI
API schema to support discovery and publishing of lights in a scene.

ListAPI
Deprecated

MeshLightAPI
This is the preferred API schema to apply to Mesh type prims when adding light behaviors to a mesh.

NonboundableLightBase
Base class for intrinsic lights that are not boundable.

PluginLight
Light that provides properties that allow it to identify an external SdrShadingNode definition, through UsdShadeNodeDefAPI, that can be provided to render delegates without the need to provide a schema definition for the light's type.

PluginLightFilter
Light filter that provides properties that allow it to identify an external SdrShadingNode definition, through UsdShadeNodeDefAPI, that can be provided to render delegates without the need to provide a schema definition for the light filter's type.

PortalLight
A rectangular portal in the local XY plane that guides sampling of a dome light.

RectLight
Light emitted from one side of a rectangle.

ShadowAPI
Controls to refine a light's shadow behavior.

ShapingAPI
Controls for shaping a light's emission.

SphereLight
Light emitted outward from a sphere.

Tokens

VolumeLightAPI
This is the preferred API schema to apply to Volume type prims when adding light behaviors to a volume.

class pxr.UsdLux.BoundableLightBase
Base class for intrinsic lights that are boundable.
The primary purpose of this class is to provide a direct API to the
functions provided by LightAPI for concrete derived light types.
Methods:

CreateColorAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateColorAttr() .

CreateColorTemperatureAttr(defaultValue, ...)
See UsdLuxLightAPI::CreateColorTemperatureAttr() .

CreateDiffuseAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateDiffuseAttr() .

CreateEnableColorTemperatureAttr(...)
See UsdLuxLightAPI::CreateEnableColorTemperatureAttr() .

CreateExposureAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateExposureAttr() .

CreateFiltersRel()
See UsdLuxLightAPI::CreateFiltersRel() .

CreateIntensityAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateIntensityAttr() .

CreateNormalizeAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateNormalizeAttr() .

CreateSpecularAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateSpecularAttr() .

Get
classmethod Get(stage, path) -> BoundableLightBase

GetColorAttr()
See UsdLuxLightAPI::GetColorAttr() .

GetColorTemperatureAttr()
See UsdLuxLightAPI::GetColorTemperatureAttr() .

GetDiffuseAttr()
See UsdLuxLightAPI::GetDiffuseAttr() .

GetEnableColorTemperatureAttr()
See UsdLuxLightAPI::GetEnableColorTemperatureAttr() .

GetExposureAttr()
See UsdLuxLightAPI::GetExposureAttr() .

GetFiltersRel()
See UsdLuxLightAPI::GetFiltersRel() .

GetIntensityAttr()
See UsdLuxLightAPI::GetIntensityAttr() .

GetNormalizeAttr()
See UsdLuxLightAPI::GetNormalizeAttr() .

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

GetSpecularAttr()
See UsdLuxLightAPI::GetSpecularAttr() .

LightAPI()
Contructs and returns a UsdLuxLightAPI object for this light.

CreateColorAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateColorAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateColorTemperatureAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateColorTemperatureAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateDiffuseAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateDiffuseAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateEnableColorTemperatureAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateEnableColorTemperatureAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateExposureAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateExposureAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateFiltersRel() → Relationship
See UsdLuxLightAPI::CreateFiltersRel() .

CreateIntensityAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateIntensityAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateNormalizeAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateNormalizeAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateSpecularAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateSpecularAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

static Get()
classmethod Get(stage, path) -> BoundableLightBase
Return a UsdLuxBoundableLightBase 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:
UsdLuxBoundableLightBase(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetColorAttr() → Attribute
See UsdLuxLightAPI::GetColorAttr() .

GetColorTemperatureAttr() → Attribute
See UsdLuxLightAPI::GetColorTemperatureAttr() .

GetDiffuseAttr() → Attribute
See UsdLuxLightAPI::GetDiffuseAttr() .

GetEnableColorTemperatureAttr() → Attribute
See UsdLuxLightAPI::GetEnableColorTemperatureAttr() .

GetExposureAttr() → Attribute
See UsdLuxLightAPI::GetExposureAttr() .

GetFiltersRel() → Relationship
See UsdLuxLightAPI::GetFiltersRel() .

GetIntensityAttr() → Attribute
See UsdLuxLightAPI::GetIntensityAttr() .

GetNormalizeAttr() → Attribute
See UsdLuxLightAPI::GetNormalizeAttr() .

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) – 

GetSpecularAttr() → Attribute
See UsdLuxLightAPI::GetSpecularAttr() .

LightAPI() → LightAPI
Contructs and returns a UsdLuxLightAPI object for this light.

class pxr.UsdLux.CylinderLight
Light emitted outward from a cylinder. The cylinder is centered at the
origin and has its major axis on the X axis. The cylinder does not
emit light from the flat end-caps.
Methods:

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

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

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

Define
classmethod Define(stage, path) -> CylinderLight

Get
classmethod Get(stage, path) -> CylinderLight

GetLengthAttr()
Width of the rectangle, in the local X axis.

GetRadiusAttr()
Radius of the cylinder.

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

GetTreatAsLineAttr()
A hint that this light can be treated as a'line'light (effectively, a zero-radius cylinder) by renderers that benefit from non-area lighting.

CreateLengthAttr(defaultValue, writeSparsely) → Attribute
See GetLengthAttr() , 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) – 

CreateRadiusAttr(defaultValue, writeSparsely) → Attribute
See GetRadiusAttr() , 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) – 

CreateTreatAsLineAttr(defaultValue, writeSparsely) → Attribute
See GetTreatAsLineAttr() , and also Create vs Get Property Methods for
when to use Get vs Create.
If specified, author defaultValue as the attribute’s default,
sparsely (when it makes sense to do so) if writeSparsely is
true - the default for writeSparsely is false .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

static Define()
classmethod Define(stage, path) -> CylinderLight
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) -> CylinderLight
Return a UsdLuxCylinderLight 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:
UsdLuxCylinderLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetLengthAttr() → Attribute
Width of the rectangle, in the local X axis.
Declaration
float inputs:length = 1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetRadiusAttr() → Attribute
Radius of the cylinder.
Declaration
float inputs:radius = 0.5
C++ Type
float
Usd Type
SdfValueTypeNames->Float

static GetSchemaAttributeNames()
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]
Return a vector of names of all pre-declared attributes for this
schema class and all its ancestor classes.
Does not include attributes that may be authored by custom/extended
methods of the schemas involved.

Parameters
includeInherited (bool) – 

GetTreatAsLineAttr() → Attribute
A hint that this light can be treated as a’line’light (effectively, a
zero-radius cylinder) by renderers that benefit from non-area
lighting.
Renderers that only support area lights can disregard this.
Declaration
bool treatAsLine = 0
C++ Type
bool
Usd Type
SdfValueTypeNames->Bool

class pxr.UsdLux.DiskLight
Light emitted from one side of a circular disk. The disk is centered
in the XY plane and emits light along the -Z axis.
Methods:

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

Define
classmethod Define(stage, path) -> DiskLight

Get
classmethod Get(stage, path) -> DiskLight

GetRadiusAttr()
Radius of the disk.

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

CreateRadiusAttr(defaultValue, writeSparsely) → Attribute
See GetRadiusAttr() , and also Create vs Get Property Methods for when
to use Get vs Create.
If specified, author defaultValue as the attribute’s default,
sparsely (when it makes sense to do so) if writeSparsely is
true - the default for writeSparsely is false .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

static Define()
classmethod Define(stage, path) -> DiskLight
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) -> DiskLight
Return a UsdLuxDiskLight 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:
UsdLuxDiskLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetRadiusAttr() → Attribute
Radius of the disk.
Declaration
float inputs:radius = 0.5
C++ Type
float
Usd Type
SdfValueTypeNames->Float

static GetSchemaAttributeNames()
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]
Return a vector of names of all pre-declared attributes for this
schema class and all its ancestor classes.
Does not include attributes that may be authored by custom/extended
methods of the schemas involved.

Parameters
includeInherited (bool) – 

class pxr.UsdLux.DistantLight
Light emitted from a distant source along the -Z axis. Also known as a
directional light.
Methods:

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

Define
classmethod Define(stage, path) -> DistantLight

Get
classmethod Get(stage, path) -> DistantLight

GetAngleAttr()
Angular size of the light in degrees.

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

CreateAngleAttr(defaultValue, writeSparsely) → Attribute
See GetAngleAttr() , and also Create vs Get Property Methods for when
to use Get vs Create.
If specified, author defaultValue as the attribute’s default,
sparsely (when it makes sense to do so) if writeSparsely is
true - the default for writeSparsely is false .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

static Define()
classmethod Define(stage, path) -> DistantLight
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) -> DistantLight
Return a UsdLuxDistantLight 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:
UsdLuxDistantLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetAngleAttr() → Attribute
Angular size of the light in degrees.
As an example, the Sun is approximately 0.53 degrees as seen from
Earth. Higher values broaden the light and therefore soften shadow
edges.
Declaration
float inputs:angle = 0.53
C++ Type
float
Usd Type
SdfValueTypeNames->Float

static GetSchemaAttributeNames()
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]
Return a vector of names of all pre-declared attributes for this
schema class and all its ancestor classes.
Does not include attributes that may be authored by custom/extended
methods of the schemas involved.

Parameters
includeInherited (bool) – 

class pxr.UsdLux.DomeLight
Light emitted inward from a distant external environment, such as a
sky or IBL light probe. The orientation of a dome light with a latlong
texture is expected to match the OpenEXR specification for latlong
environment maps. From the OpenEXR documentation:
Latitude-Longitude Map:
The environment is projected onto the image using polar coordinates
(latitude and longitude). A pixel’s x coordinate corresponds to its
longitude, and the y coordinate corresponds to its latitude. Pixel
(dataWindow.min.x, dataWindow.min.y) has latitude +pi/2 and longitude
+pi; pixel (dataWindow.max.x, dataWindow.max.y) has latitude -pi/2 and
longitude -pi.
In 3D space, latitudes -pi/2 and +pi/2 correspond to the negative and
positive y direction. Latitude 0, longitude 0 points into positive z
direction; and latitude 0, longitude pi/2 points into positive x
direction.
The size of the data window should be 2*N by N pixels (width by
height),
For any described attribute Fallback Value or Allowed Values
below that are text/tokens, the actual token is published and defined
in UsdLuxTokens. So to set an attribute to the value”rightHanded”, use
UsdLuxTokens->rightHanded as the value.
Methods:

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

CreatePortalsRel()
See GetPortalsRel() , and also Create vs Get Property Methods for when to use Get vs Create.

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

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

Define
classmethod Define(stage, path) -> DomeLight

Get
classmethod Get(stage, path) -> DomeLight

GetGuideRadiusAttr()
The radius of guide geometry to use to visualize the dome light.

GetPortalsRel()
Optional portals to guide light sampling.

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

GetTextureFileAttr()
A color texture to use on the dome, such as an HDR (high dynamic range) texture intended for IBL (image based lighting).

GetTextureFormatAttr()
Specifies the parameterization of the color map file.

OrientToStageUpAxis()
Adds a transformation op, if neeeded, to orient the dome to align with the stage's up axis.

CreateGuideRadiusAttr(defaultValue, writeSparsely) → Attribute
See GetGuideRadiusAttr() , 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) – 

CreatePortalsRel() → Relationship
See GetPortalsRel() , and also Create vs Get Property Methods for when
to use Get vs Create.

CreateTextureFileAttr(defaultValue, writeSparsely) → Attribute
See GetTextureFileAttr() , 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) – 

CreateTextureFormatAttr(defaultValue, writeSparsely) → Attribute
See GetTextureFormatAttr() , and also Create vs Get Property Methods
for when to use Get vs Create.
If specified, author defaultValue as the attribute’s default,
sparsely (when it makes sense to do so) if writeSparsely is
true - the default for writeSparsely is false .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

static Define()
classmethod Define(stage, path) -> DomeLight
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) -> DomeLight
Return a UsdLuxDomeLight 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:
UsdLuxDomeLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetGuideRadiusAttr() → Attribute
The radius of guide geometry to use to visualize the dome light.
The default is 1 km for scenes whose metersPerUnit is the USD default
of 0.01 (i.e., 1 world unit is 1 cm).
Declaration
float guideRadius = 100000
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetPortalsRel() → Relationship
Optional portals to guide light sampling.

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) – 

GetTextureFileAttr() → Attribute
A color texture to use on the dome, such as an HDR (high dynamic
range) texture intended for IBL (image based lighting).
Declaration
asset inputs:texture:file
C++ Type
SdfAssetPath
Usd Type
SdfValueTypeNames->Asset

GetTextureFormatAttr() → Attribute
Specifies the parameterization of the color map file.
Valid values are:

automatic: Tries to determine the layout from the file itself.
For example, Renderman texture files embed an explicit
parameterization.
latlong: Latitude as X, longitude as Y.
mirroredBall: An image of the environment reflected in a sphere,
using an implicitly orthogonal projection.
angular: Similar to mirroredBall but the radial dimension is
mapped linearly to the angle, providing better sampling at the edges.
cubeMapVerticalCross: A cube map with faces laid out as a
vertical cross.

Declaration
token inputs:texture:format ="automatic"
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
Allowed Values
automatic, latlong, mirroredBall, angular, cubeMapVerticalCross

OrientToStageUpAxis() → None
Adds a transformation op, if neeeded, to orient the dome to align with
the stage’s up axis.
Uses UsdLuxTokens->orientToStageUpAxis as the op suffix. If an op with
this suffix already exists, this method assumes it is already applying
the proper correction and does nothing further. If no op is required
to match the stage’s up axis, no op will be created.
UsdGeomXformOp
UsdGeomGetStageUpAxis

class pxr.UsdLux.GeometryLight
Deprecated
Light emitted outward from a geometric prim (UsdGeomGprim), which is
typically a mesh.
Methods:

CreateGeometryRel()
See GetGeometryRel() , and also Create vs Get Property Methods for when to use Get vs Create.

Define
classmethod Define(stage, path) -> GeometryLight

Get
classmethod Get(stage, path) -> GeometryLight

GetGeometryRel()
Relationship to the geometry to use as the light source.

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

CreateGeometryRel() → Relationship
See GetGeometryRel() , and also Create vs Get Property Methods for
when to use Get vs Create.

static Define()
classmethod Define(stage, path) -> GeometryLight
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) -> GeometryLight
Return a UsdLuxGeometryLight 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:
UsdLuxGeometryLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetGeometryRel() → Relationship
Relationship to the geometry to use as the light source.

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.UsdLux.LightAPI
API schema that imparts the quality of being a light onto a prim.
A light is any prim that has this schema applied to it. This is true
regardless of whether LightAPI is included as a built-in API of the
prim type (e.g. RectLight or DistantLight) or is applied directly to a
Gprim that should be treated as a light.
Linking
Lights can be linked to geometry. Linking controls which geometry a
light illuminates, and which geometry casts shadows from the light.
Linking is specified as collections (UsdCollectionAPI) which can be
accessed via GetLightLinkCollection() and GetShadowLinkCollection().
Note that these collections have their includeRoot set to true, so
that lights will illuminate and cast shadows from all objects by
default. To illuminate only a specific set of objects, there are two
options. One option is to modify the collection paths to explicitly
exclude everything else, assuming it is known; the other option is to
set includeRoot to false and explicitly include the desired objects.
These are complementary approaches that may each be preferable
depending on the scenario and how to best express the intent of the
light setup.
For any described attribute Fallback Value or Allowed Values
below that are text/tokens, the actual token is published and defined
in UsdLuxTokens. So to set an attribute to the value”rightHanded”, use
UsdLuxTokens->rightHanded as the value.
Methods:

Apply
classmethod Apply(prim) -> LightAPI

CanApply
classmethod CanApply(prim, whyNot) -> bool

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

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

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

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

CreateEnableColorTemperatureAttr(...)
See GetEnableColorTemperatureAttr() , and also Create vs Get Property Methods for when to use Get vs Create.

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

CreateFiltersRel()
See GetFiltersRel() , and also Create vs Get Property Methods for when to use Get vs Create.

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

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

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

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

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

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

CreateShaderIdAttrForRenderContext(...)
Creates the shader ID attribute for the given renderContext .

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

Get
classmethod Get(stage, path) -> LightAPI

GetColorAttr()
The color of emitted light, in energy-linear terms.

GetColorTemperatureAttr()
Color temperature, in degrees Kelvin, representing the white point.

GetDiffuseAttr()
A multiplier for the effect of this light on the diffuse response of materials.

GetEnableColorTemperatureAttr()
Enables using colorTemperature.

GetExposureAttr()
Scales the power of the light exponentially as a power of 2 (similar to an F-stop control over exposure).

GetFiltersRel()
Relationship to the light filters that apply to this light.

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

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

GetIntensityAttr()
Scales the power of the light linearly.

GetLightLinkCollectionAPI()
Return the UsdCollectionAPI interface used for examining and modifying the light-linking of this light.

GetMaterialSyncModeAttr()
For a LightAPI applied to geometry that has a bound Material, which is entirely or partly emissive, this specifies the relationship of the Material response to the lighting response.

GetNormalizeAttr()
Normalizes power by the surface area of the light.

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]

GetShaderId(renderContexts)
Return the light's shader ID for the given list of available renderContexts .

GetShaderIdAttr()
Default ID for the light's shader.

GetShaderIdAttrForRenderContext(renderContext)
Returns the shader ID attribute for the given renderContext .

GetShadowLinkCollectionAPI()
Return the UsdCollectionAPI interface used for examining and modifying the shadow-linking of this light.

GetSpecularAttr()
A multiplier for the effect of this light on the specular response of materials.

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

ConnectableAPI() → ConnectableAPI
Contructs and returns a UsdShadeConnectableAPI object with this light.
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 UsdLuxLightAPI will auto-convert to a UsdShadeConnectableAPI when
passed to functions that want to act generically on a connectable
UsdShadeConnectableAPI object.

CreateColorAttr(defaultValue, writeSparsely) → Attribute
See GetColorAttr() , 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) – 

CreateColorTemperatureAttr(defaultValue, writeSparsely) → Attribute
See GetColorTemperatureAttr() , 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) – 

CreateDiffuseAttr(defaultValue, writeSparsely) → Attribute
See GetDiffuseAttr() , 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) – 

CreateEnableColorTemperatureAttr(defaultValue, writeSparsely) → Attribute
See GetEnableColorTemperatureAttr() , 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) – 

CreateExposureAttr(defaultValue, writeSparsely) → Attribute
See GetExposureAttr() , 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) – 

CreateFiltersRel() → Relationship
See GetFiltersRel() , and also Create vs Get Property Methods for when
to use Get vs Create.

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 lights are connectable.

Parameters

name (str) – 
typeName (ValueTypeName) – 

CreateIntensityAttr(defaultValue, writeSparsely) → Attribute
See GetIntensityAttr() , 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) – 

CreateMaterialSyncModeAttr(defaultValue, writeSparsely) → Attribute
See GetMaterialSyncModeAttr() , 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) – 

CreateNormalizeAttr(defaultValue, writeSparsely) → Attribute
See GetNormalizeAttr() , 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) – 

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 light cannot be connected, as
their value is assumed to be computed externally.

Parameters

name (str) – 
typeName (ValueTypeName) – 

CreateShaderIdAttr(defaultValue, writeSparsely) → Attribute
See GetShaderIdAttr() , 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) – 

CreateShaderIdAttrForRenderContext(renderContext, defaultValue, writeSparsely) → Attribute
Creates the shader ID attribute for the given renderContext .
See GetShaderIdAttrForRenderContext() , 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

renderContext (str) – 
defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateSpecularAttr(defaultValue, writeSparsely) → Attribute
See GetSpecularAttr() , 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) -> LightAPI
Return a UsdLuxLightAPI 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:
UsdLuxLightAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetColorAttr() → Attribute
The color of emitted light, in energy-linear terms.
Declaration
color3f inputs:color = (1, 1, 1)
C++ Type
GfVec3f
Usd Type
SdfValueTypeNames->Color3f

GetColorTemperatureAttr() → Attribute
Color temperature, in degrees Kelvin, representing the white point.
The default is a common white point, D65. Lower values are warmer and
higher values are cooler. The valid range is from 1000 to 10000. Only
takes effect when enableColorTemperature is set to true. When active,
the computed result multiplies against the color attribute. See
UsdLuxBlackbodyTemperatureAsRgb() .
Declaration
float inputs:colorTemperature = 6500
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetDiffuseAttr() → Attribute
A multiplier for the effect of this light on the diffuse response of
materials.
This is a non-physical control.
Declaration
float inputs:diffuse = 1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetEnableColorTemperatureAttr() → Attribute
Enables using colorTemperature.
Declaration
bool inputs:enableColorTemperature = 0
C++ Type
bool
Usd Type
SdfValueTypeNames->Bool

GetExposureAttr() → Attribute
Scales the power of the light exponentially as a power of 2 (similar
to an F-stop control over exposure).
The result is multiplied against the intensity.
Declaration
float inputs:exposure = 0
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetFiltersRel() → Relationship
Relationship to the light filters that apply to this light.

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) – 

GetIntensityAttr() → Attribute
Scales the power of the light linearly.
Declaration
float inputs:intensity = 1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetLightLinkCollectionAPI() → CollectionAPI
Return the UsdCollectionAPI interface used for examining and modifying
the light-linking of this light.
Light-linking controls which geometry this light illuminates.

GetMaterialSyncModeAttr() → Attribute
For a LightAPI applied to geometry that has a bound Material, which is
entirely or partly emissive, this specifies the relationship of the
Material response to the lighting response.
Valid values are:

materialGlowTintsLight: All primary and secondary rays see the
emissive/glow response as dictated by the bound Material while the
base color seen by light rays (which is then modulated by all of the
other LightAPI controls) is the multiplication of the color feeding
the emission/glow input of the Material (i.e. its surface or volume
shader) with the scalar or pattern input to inputs:color. This
allows the light’s color to tint the geometry’s glow color while
preserving access to intensity and other light controls as ways to
further modulate the illumination.
independent: All primary and secondary rays see the emissive/glow
response as dictated by the bound Material, while the base color seen
by light rays is determined solely by inputs:color. Note that for
partially emissive geometry (in which some parts are reflective rather
than emissive), a suitable pattern must be connected to the light’s
color input, or else the light will radiate uniformly from the
geometry.
noMaterialResponse: The geometry behaves as if there is no
Material bound at all, i.e. there is no diffuse, specular, or
transmissive response. The base color of light rays is entirely
controlled by the inputs:color. This is the standard mode
for”canonical”lights in UsdLux and indicates to renderers that a
Material will either never be bound or can always be ignored.

Declaration
uniform token light:materialSyncMode ="noMaterialResponse"
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
Variability
SdfVariabilityUniform
Allowed Values
materialGlowTintsLight, independent, noMaterialResponse

GetNormalizeAttr() → Attribute
Normalizes power by the surface area of the light.
This makes it easier to independently adjust the power and shape of
the light, by causing the power to not vary with the area or angular
size of the light.
Declaration
bool inputs:normalize = 0
C++ Type
bool
Usd Type
SdfValueTypeNames->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) – 

GetShaderId(renderContexts) → str
Return the light’s shader ID for the given list of available
renderContexts .
The shader ID returned by this function is the identifier to use when
looking up the shader definition for this light in the shader
registry.
The render contexts are expected to be listed in priority order, so
for each render context provided, this will try to find the shader ID
attribute specific to that render context (see
GetShaderIdAttrForRenderContext() ) and will return the value of the
first one found that has a non-empty value. If no shader ID value can
be found for any of the given render contexts or renderContexts is
empty, then this will return the value of the default shader ID
attribute (see GetShaderIdAttr() ).

Parameters
renderContexts (list[TfToken]) – 

GetShaderIdAttr() → Attribute
Default ID for the light’s shader.
This defines the shader ID for this light when a render context
specific shader ID is not available.
The default shaderId for the intrinsic UsdLux lights (RectLight,
DistantLight, etc.) are set to default to the light’s type name. For
each intrinsic UsdLux light, we will always register an SdrShaderNode
in the SdrRegistry, with the identifier matching the type name and the
source type”USD”, that corresponds to the light’s inputs.
GetShaderId
GetShaderIdAttrForRenderContext
SdrRegistry::GetShaderNodeByIdentifier
SdrRegistry::GetShaderNodeByIdentifierAndType
Declaration
uniform token light:shaderId =""
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
Variability
SdfVariabilityUniform

GetShaderIdAttrForRenderContext(renderContext) → Attribute
Returns the shader ID attribute for the given renderContext .
If renderContext is non-empty, this will try to return an
attribute named light:shaderId with the namespace prefix
renderContext . For example, if the passed in render context
is”ri”then the attribute returned by this function would have the
following signature:
Declaration
token ri:light:shaderId
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
If the render context is empty, this will return the default shader ID
attribute as returned by GetShaderIdAttr() .

Parameters
renderContext (str) – 

GetShadowLinkCollectionAPI() → CollectionAPI
Return the UsdCollectionAPI interface used for examining and modifying
the shadow-linking of this light.
Shadow-linking controls which geometry casts shadows from this light.

GetSpecularAttr() → Attribute
A multiplier for the effect of this light on the specular response of
materials.
This is a non-physical control.
Declaration
float inputs:specular = 1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

class pxr.UsdLux.LightFilter
A light filter modifies the effect of a light. Lights refer to filters
via relationships so that filters may be shared.
Linking
Filters can be linked to geometry. Linking controls which geometry a
light-filter affects, when considering the light filters attached to a
light illuminating the geometry.
Linking is specified as a collection (UsdCollectionAPI) which can be
accessed via GetFilterLinkCollection().
For any described attribute Fallback Value or Allowed Values
below that are text/tokens, the actual token is published and defined
in UsdLuxTokens. So to set an attribute to the value”rightHanded”, use
UsdLuxTokens->rightHanded as the value.
Methods:

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

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.

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

CreateShaderIdAttrForRenderContext(...)
Creates the shader ID attribute for the given renderContext .

Define
classmethod Define(stage, path) -> LightFilter

Get
classmethod Get(stage, path) -> LightFilter

GetFilterLinkCollectionAPI()
Return the UsdCollectionAPI interface used for examining and modifying the filter-linking of this light filter.

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]

GetShaderId(renderContexts)
Return the light filter's shader ID for the given list of available renderContexts .

GetShaderIdAttr()
Default ID for the light filter's shader.

GetShaderIdAttrForRenderContext(renderContext)
Returns the shader ID attribute for the given renderContext .

ConnectableAPI() → ConnectableAPI
Contructs and returns a UsdShadeConnectableAPI object with this light
filter.
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 UsdLuxLightFilter 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. Inputs on light filters 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 light filter cannot be connected,
as their value is assumed to be computed externally.

Parameters

name (str) – 
typeName (ValueTypeName) – 

CreateShaderIdAttr(defaultValue, writeSparsely) → Attribute
See GetShaderIdAttr() , 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) – 

CreateShaderIdAttrForRenderContext(renderContext, defaultValue, writeSparsely) → Attribute
Creates the shader ID attribute for the given renderContext .
See GetShaderIdAttrForRenderContext() , 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

renderContext (str) – 
defaultValue (VtValue) – 
writeSparsely (bool) – 

static Define()
classmethod Define(stage, path) -> LightFilter
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) -> LightFilter
Return a UsdLuxLightFilter 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:
UsdLuxLightFilter(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetFilterLinkCollectionAPI() → CollectionAPI
Return the UsdCollectionAPI interface used for examining and modifying
the filter-linking of this light filter.
Linking controls which geometry this light filter affects.

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) – 

GetShaderId(renderContexts) → str
Return the light filter’s shader ID for the given list of available
renderContexts .
The shader ID returned by this function is the identifier to use when
looking up the shader definition for this light filter in the shader
registry.
The render contexts are expected to be listed in priority order, so
for each render context provided, this will try to find the shader ID
attribute specific to that render context (see
GetShaderIdAttrForRenderContext() ) and will return the value of the
first one found that has a non-empty value. If no shader ID value can
be found for any of the given render contexts or renderContexts is
empty, then this will return the value of the default shader ID
attribute (see GetShaderIdAttr() ).

Parameters
renderContexts (list[TfToken]) – 

GetShaderIdAttr() → Attribute
Default ID for the light filter’s shader.
This defines the shader ID for this light filter when a render context
specific shader ID is not available.
GetShaderId
GetShaderIdAttrForRenderContext
SdrRegistry::GetShaderNodeByIdentifier
SdrRegistry::GetShaderNodeByIdentifierAndType
Declaration
uniform token lightFilter:shaderId =""
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
Variability
SdfVariabilityUniform

GetShaderIdAttrForRenderContext(renderContext) → Attribute
Returns the shader ID attribute for the given renderContext .
If renderContext is non-empty, this will try to return an
attribute named lightFilter:shaderId with the namespace prefix
renderContext . For example, if the passed in render context
is”ri”then the attribute returned by this function would have the
following signature:
Declaration
token ri:lightFilter:shaderId
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
If the render context is empty, this will return the default shader ID
attribute as returned by GetShaderIdAttr() .

Parameters
renderContext (str) – 

class pxr.UsdLux.LightListAPI
API schema to support discovery and publishing of lights in a scene.

## Discovering Lights via Traversal

To motivate this API, consider what is required to discover all lights
in a scene. We must load all payloads and traverse all prims:
01  // Load everything on the stage so we can find all lights,
02  // including those inside payloads
03  stage->Load();
04
05  // Traverse all prims, checking if they have an applied UsdLuxLightAPI
06  // (Note: ignoring instancing and a few other things for simplicity)
07  SdfPathVector lights;
08  for (UsdPrim prim: stage->Traverse()) {
09      if (prim.HasAPI<UsdLuxLightAPI>()) {
10          lights.push_back(i->GetPath());
11      }
12  }

This traversal  suitably elaborated to handle certain details  is the
first and simplest thing UsdLuxLightListAPI provides.
UsdLuxLightListAPI::ComputeLightList() performs this traversal and
returns all lights in the scene:
01  UsdLuxLightListAPI listAPI(stage->GetPseudoRoot());
02  SdfPathVector lights = listAPI.ComputeLightList();

## Publishing a Cached Light List

Consider a USD client that needs to quickly discover lights but wants
to defer loading payloads and traversing the entire scene where
possible, and is willing to do up-front computation and caching to
achieve that.
UsdLuxLightListAPI provides a way to cache the computed light list, by
publishing the list of lights onto prims in the model hierarchy.
Consider a big set that contains lights:
01  def Xform "BigSetWithLights" (
02      kind = "assembly"
03      payload = @BigSetWithLights.usd@   // Heavy payload
04  ) {
05      // Pre-computed, cached list of lights inside payload
06      rel lightList = [
07          <./Lights/light_1>,
08          <./Lights/light_2>,
09          \.\.\.
10      ]
11      token lightList:cacheBehavior = "consumeAndContinue";
12  }

The lightList relationship encodes a set of lights, and the
lightList:cacheBehavior property provides fine-grained control over
how to use that cache. (See details below.)
The cache can be created by first invoking
ComputeLightList(ComputeModeIgnoreCache) to pre-compute the list and
then storing the result with UsdLuxLightListAPI::StoreLightList() .
To enable efficient retrieval of the cache, it should be stored on a
model hierarchy prim. Furthermore, note that while you can use a
UsdLuxLightListAPI bound to the pseudo-root prim to query the lights
(as in the example above) because it will perform a traversal over
descendants, you cannot store the cache back to the pseduo-root prim.
To consult the cached list, we invoke
ComputeLightList(ComputeModeConsultModelHierarchyCache):
01  // Find and load all lights, using lightList cache where available
02  UsdLuxLightListAPI list(stage->GetPseudoRoot());
03  SdfPathSet lights = list.ComputeLightList(
04      UsdLuxLightListAPI::ComputeModeConsultModelHierarchyCache);
05  stage.LoadAndUnload(lights, SdfPathSet());

In this mode, ComputeLightList() will traverse the model hierarchy,
accumulating cached light lists.

## Controlling Cache Behavior

The lightList:cacheBehavior property gives additional fine-grained
control over cache behavior:

The fallback value,”ignore”, indicates that the lightList should
be disregarded. This provides a way to invalidate cache entries. Note
that unless”ignore”is specified, a lightList with an empty list of
targets is considered a cache indicating that no lights are present.
The value”consumeAndContinue”indicates that the cache should be
consulted to contribute lights to the scene, and that recursion should
continue down the model hierarchy in case additional lights are added
as descedants. This is the default value established when
StoreLightList() is invoked. This behavior allows the lights within a
large model, such as the BigSetWithLights example above, to be
published outside the payload, while also allowing referencing and
layering to add additional lights over that set.
The value”consumeAndHalt”provides a way to terminate recursive
traversal of the scene for light discovery. The cache will be
consulted but no descendant prims will be examined.

## Instancing

Where instances are present, UsdLuxLightListAPI::ComputeLightList()
will return the instance-unique paths to any lights discovered within
those instances. Lights within a UsdGeomPointInstancer will not be
returned, however, since they cannot be referred to solely via paths.
For any described attribute Fallback Value or Allowed Values
below that are text/tokens, the actual token is published and defined
in UsdLuxTokens. So to set an attribute to the value”rightHanded”, use
UsdLuxTokens->rightHanded as the value.
Classes:

ComputeMode
Runtime control over whether to consult stored lightList caches.

Methods:

Apply
classmethod Apply(prim) -> LightListAPI

CanApply
classmethod CanApply(prim, whyNot) -> bool

ComputeLightList(mode)
Computes and returns the list of lights and light filters in the stage, optionally consulting a cached result.

CreateLightListCacheBehaviorAttr(...)
See GetLightListCacheBehaviorAttr() , and also Create vs Get Property Methods for when to use Get vs Create.

CreateLightListRel()
See GetLightListRel() , and also Create vs Get Property Methods for when to use Get vs Create.

Get
classmethod Get(stage, path) -> LightListAPI

GetLightListCacheBehaviorAttr()
Controls how the lightList should be interpreted.

GetLightListRel()
Relationship to lights in the scene.

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

InvalidateLightList()
Mark any stored lightlist as invalid, by setting the lightList:cacheBehavior attribute to ignore.

StoreLightList(arg1)
Store the given paths as the lightlist for this prim.

Attributes:

ComputeModeConsultModelHierarchyCache

ComputeModeIgnoreCache

class ComputeMode
Runtime control over whether to consult stored lightList caches.
Methods:

GetValueFromName

Attributes:

allValues

static GetValueFromName()

allValues = (UsdLux.LightListAPI.ComputeModeConsultModelHierarchyCache, UsdLux.LightListAPI.ComputeModeIgnoreCache)

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

ComputeLightList(mode) → SdfPathSet
Computes and returns the list of lights and light filters in the
stage, optionally consulting a cached result.
In ComputeModeIgnoreCache mode, caching is ignored, and this does a
prim traversal looking for prims that have a UsdLuxLightAPI or are of
type UsdLuxLightFilter.
In ComputeModeConsultModelHierarchyCache, this does a traversal only
of the model hierarchy. In this traversal, any lights that live as
model hierarchy prims are accumulated, as well as any paths stored in
lightList caches. The lightList:cacheBehavior attribute gives further
control over the cache behavior; see the class overview for details.
When instances are present, ComputeLightList(ComputeModeIgnoreCache)
will return the instance-uniqiue paths to any lights discovered within
those instances. Lights within a UsdGeomPointInstancer will not be
returned, however, since they cannot be referred to solely via paths.

Parameters
mode (ComputeMode) – 

CreateLightListCacheBehaviorAttr(defaultValue, writeSparsely) → Attribute
See GetLightListCacheBehaviorAttr() , 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) – 

CreateLightListRel() → Relationship
See GetLightListRel() , and also Create vs Get Property Methods for
when to use Get vs Create.

static Get()
classmethod Get(stage, path) -> LightListAPI
Return a UsdLuxLightListAPI 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:
UsdLuxLightListAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetLightListCacheBehaviorAttr() → Attribute
Controls how the lightList should be interpreted.
Valid values are:

consumeAndHalt: The lightList should be consulted, and if it
exists, treated as a final authoritative statement of any lights that
exist at or below this prim, halting recursive discovery of lights.
consumeAndContinue: The lightList should be consulted, but
recursive traversal over nameChildren should continue in case
additional lights are added by descendants.
ignore: The lightList should be entirely ignored. This provides a
simple way to temporarily invalidate an existing cache. This is the
fallback behavior.

Declaration
token lightList:cacheBehavior
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
Allowed Values
consumeAndHalt, consumeAndContinue, ignore

GetLightListRel() → Relationship
Relationship to lights in the scene.

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) – 

InvalidateLightList() → None
Mark any stored lightlist as invalid, by setting the
lightList:cacheBehavior attribute to ignore.

StoreLightList(arg1) → None
Store the given paths as the lightlist for this prim.
Paths that do not have this prim’s path as a prefix will be silently
ignored. This will set the listList:cacheBehavior
to”consumeAndContinue”.

Parameters
arg1 (SdfPathSet) – 

ComputeModeConsultModelHierarchyCache = UsdLux.LightListAPI.ComputeModeConsultModelHierarchyCache

ComputeModeIgnoreCache = UsdLux.LightListAPI.ComputeModeIgnoreCache

class pxr.UsdLux.ListAPI
Deprecated
Use LightListAPI instead
For any described attribute Fallback Value or Allowed Values
below that are text/tokens, the actual token is published and defined
in UsdLuxTokens. So to set an attribute to the value”rightHanded”, use
UsdLuxTokens->rightHanded as the value.
Classes:

ComputeMode
Runtime control over whether to consult stored lightList caches.

Methods:

Apply
classmethod Apply(prim) -> ListAPI

CanApply
classmethod CanApply(prim, whyNot) -> bool

ComputeLightList(mode)
Computes and returns the list of lights and light filters in the stage, optionally consulting a cached result.

CreateLightListCacheBehaviorAttr(...)
See GetLightListCacheBehaviorAttr() , and also Create vs Get Property Methods for when to use Get vs Create.

CreateLightListRel()
See GetLightListRel() , and also Create vs Get Property Methods for when to use Get vs Create.

Get
classmethod Get(stage, path) -> ListAPI

GetLightListCacheBehaviorAttr()
Controls how the lightList should be interpreted.

GetLightListRel()
Relationship to lights in the scene.

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

InvalidateLightList()
Mark any stored lightlist as invalid, by setting the lightList:cacheBehavior attribute to ignore.

StoreLightList(arg1)
Store the given paths as the lightlist for this prim.

Attributes:

ComputeModeConsultModelHierarchyCache

ComputeModeIgnoreCache

class ComputeMode
Runtime control over whether to consult stored lightList caches.
Methods:

GetValueFromName

Attributes:

allValues

static GetValueFromName()

allValues = (UsdLux.ListAPI.ComputeModeConsultModelHierarchyCache, UsdLux.ListAPI.ComputeModeIgnoreCache)

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

ComputeLightList(mode) → SdfPathSet
Computes and returns the list of lights and light filters in the
stage, optionally consulting a cached result.
In ComputeModeIgnoreCache mode, caching is ignored, and this does a
prim traversal looking for prims that have a UsdLuxLightAPI or are of
type UsdLuxLightFilter.
In ComputeModeConsultModelHierarchyCache, this does a traversal only
of the model hierarchy. In this traversal, any lights that live as
model hierarchy prims are accumulated, as well as any paths stored in
lightList caches. The lightList:cacheBehavior attribute gives further
control over the cache behavior; see the class overview for details.
When instances are present, ComputeLightList(ComputeModeIgnoreCache)
will return the instance-uniqiue paths to any lights discovered within
those instances. Lights within a UsdGeomPointInstancer will not be
returned, however, since they cannot be referred to solely via paths.

Parameters
mode (ComputeMode) – 

CreateLightListCacheBehaviorAttr(defaultValue, writeSparsely) → Attribute
See GetLightListCacheBehaviorAttr() , 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) – 

CreateLightListRel() → Relationship
See GetLightListRel() , and also Create vs Get Property Methods for
when to use Get vs Create.

static Get()
classmethod Get(stage, path) -> ListAPI
Return a UsdLuxListAPI 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:
UsdLuxListAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetLightListCacheBehaviorAttr() → Attribute
Controls how the lightList should be interpreted.
Valid values are:

consumeAndHalt: The lightList should be consulted, and if it
exists, treated as a final authoritative statement of any lights that
exist at or below this prim, halting recursive discovery of lights.
consumeAndContinue: The lightList should be consulted, but
recursive traversal over nameChildren should continue in case
additional lights are added by descendants.
ignore: The lightList should be entirely ignored. This provides a
simple way to temporarily invalidate an existing cache. This is the
fallback behavior.

Declaration
token lightList:cacheBehavior
C++ Type
TfToken
Usd Type
SdfValueTypeNames->Token
Allowed Values
consumeAndHalt, consumeAndContinue, ignore

GetLightListRel() → Relationship
Relationship to lights in the scene.

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) – 

InvalidateLightList() → None
Mark any stored lightlist as invalid, by setting the
lightList:cacheBehavior attribute to ignore.

StoreLightList(arg1) → None
Store the given paths as the lightlist for this prim.
Paths that do not have this prim’s path as a prefix will be silently
ignored. This will set the listList:cacheBehavior
to”consumeAndContinue”.

Parameters
arg1 (SdfPathSet) – 

ComputeModeConsultModelHierarchyCache = UsdLux.ListAPI.ComputeModeConsultModelHierarchyCache

ComputeModeIgnoreCache = UsdLux.ListAPI.ComputeModeIgnoreCache

class pxr.UsdLux.MeshLightAPI
This is the preferred API schema to apply to Mesh type prims when
adding light behaviors to a mesh. At its base, this API schema has the
built-in behavior of applying LightAPI to the mesh and overriding the
default materialSyncMode to allow the emission/glow of the bound
material to affect the color of the light. But, it additionally serves
as a hook for plugins to attach additional properties to”mesh
lights”through the creation of API schemas which are authored to auto-
apply to MeshLightAPI.
Auto applied API schemas
Methods:

Apply
classmethod Apply(prim) -> MeshLightAPI

CanApply
classmethod CanApply(prim, whyNot) -> bool

Get
classmethod Get(stage, path) -> MeshLightAPI

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

static Apply()
classmethod Apply(prim) -> MeshLightAPI
Applies this single-apply API schema to the given prim .
This information is stored by adding”MeshLightAPI”to the token-valued,
listOp metadata apiSchemas on the prim.
A valid UsdLuxMeshLightAPI object is returned upon success. An invalid
(or empty) UsdLuxMeshLightAPI object is returned upon failure. See
UsdPrim::ApplyAPI() for conditions resulting in failure.
UsdPrim::GetAppliedSchemas()
UsdPrim::HasAPI()
UsdPrim::CanApplyAPI()
UsdPrim::ApplyAPI()
UsdPrim::RemoveAPI()

Parameters
prim (Prim) – 

static CanApply()
classmethod CanApply(prim, whyNot) -> bool
Returns true if this single-apply API schema can be applied to the
given prim .
If this schema can not be a applied to the prim, this returns false
and, if provided, populates whyNot with the reason it can not be
applied.
Note that if CanApply returns false, that does not necessarily imply
that calling Apply will fail. Callers are expected to call CanApply
before calling Apply if they want to ensure that it is valid to apply
a schema.
UsdPrim::GetAppliedSchemas()
UsdPrim::HasAPI()
UsdPrim::CanApplyAPI()
UsdPrim::ApplyAPI()
UsdPrim::RemoveAPI()

Parameters

prim (Prim) – 
whyNot (str) – 

static Get()
classmethod Get(stage, path) -> MeshLightAPI
Return a UsdLuxMeshLightAPI 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:
UsdLuxMeshLightAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

static GetSchemaAttributeNames()
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]
Return a vector of names of all pre-declared attributes for this
schema class and all its ancestor classes.
Does not include attributes that may be authored by custom/extended
methods of the schemas involved.

Parameters
includeInherited (bool) – 

class pxr.UsdLux.NonboundableLightBase
Base class for intrinsic lights that are not boundable.
The primary purpose of this class is to provide a direct API to the
functions provided by LightAPI for concrete derived light types.
Methods:

CreateColorAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateColorAttr() .

CreateColorTemperatureAttr(defaultValue, ...)
See UsdLuxLightAPI::CreateColorTemperatureAttr() .

CreateDiffuseAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateDiffuseAttr() .

CreateEnableColorTemperatureAttr(...)
See UsdLuxLightAPI::CreateEnableColorTemperatureAttr() .

CreateExposureAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateExposureAttr() .

CreateFiltersRel()
See UsdLuxLightAPI::CreateFiltersRel() .

CreateIntensityAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateIntensityAttr() .

CreateNormalizeAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateNormalizeAttr() .

CreateSpecularAttr(defaultValue, writeSparsely)
See UsdLuxLightAPI::CreateSpecularAttr() .

Get
classmethod Get(stage, path) -> NonboundableLightBase

GetColorAttr()
See UsdLuxLightAPI::GetColorAttr() .

GetColorTemperatureAttr()
See UsdLuxLightAPI::GetColorTemperatureAttr() .

GetDiffuseAttr()
See UsdLuxLightAPI::GetDiffuseAttr() .

GetEnableColorTemperatureAttr()
See UsdLuxLightAPI::GetEnableColorTemperatureAttr() .

GetExposureAttr()
See UsdLuxLightAPI::GetExposureAttr() .

GetFiltersRel()
See UsdLuxLightAPI::GetFiltersRel() .

GetIntensityAttr()
See UsdLuxLightAPI::GetIntensityAttr() .

GetNormalizeAttr()
See UsdLuxLightAPI::GetNormalizeAttr() .

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

GetSpecularAttr()
See UsdLuxLightAPI::GetSpecularAttr() .

LightAPI()
Contructs and returns a UsdLuxLightAPI object for this light.

CreateColorAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateColorAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateColorTemperatureAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateColorTemperatureAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateDiffuseAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateDiffuseAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateEnableColorTemperatureAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateEnableColorTemperatureAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateExposureAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateExposureAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateFiltersRel() → Relationship
See UsdLuxLightAPI::CreateFiltersRel() .

CreateIntensityAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateIntensityAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateNormalizeAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateNormalizeAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

CreateSpecularAttr(defaultValue, writeSparsely) → Attribute
See UsdLuxLightAPI::CreateSpecularAttr() .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

static Get()
classmethod Get(stage, path) -> NonboundableLightBase
Return a UsdLuxNonboundableLightBase 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:
UsdLuxNonboundableLightBase(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetColorAttr() → Attribute
See UsdLuxLightAPI::GetColorAttr() .

GetColorTemperatureAttr() → Attribute
See UsdLuxLightAPI::GetColorTemperatureAttr() .

GetDiffuseAttr() → Attribute
See UsdLuxLightAPI::GetDiffuseAttr() .

GetEnableColorTemperatureAttr() → Attribute
See UsdLuxLightAPI::GetEnableColorTemperatureAttr() .

GetExposureAttr() → Attribute
See UsdLuxLightAPI::GetExposureAttr() .

GetFiltersRel() → Relationship
See UsdLuxLightAPI::GetFiltersRel() .

GetIntensityAttr() → Attribute
See UsdLuxLightAPI::GetIntensityAttr() .

GetNormalizeAttr() → Attribute
See UsdLuxLightAPI::GetNormalizeAttr() .

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) – 

GetSpecularAttr() → Attribute
See UsdLuxLightAPI::GetSpecularAttr() .

LightAPI() → LightAPI
Contructs and returns a UsdLuxLightAPI object for this light.

class pxr.UsdLux.PluginLight
Light that provides properties that allow it to identify an external
SdrShadingNode definition, through UsdShadeNodeDefAPI, that can be
provided to render delegates without the need to provide a schema
definition for the light’s type.
Plugin Lights and Light Filters
Methods:

Define
classmethod Define(stage, path) -> PluginLight

Get
classmethod Get(stage, path) -> PluginLight

GetNodeDefAPI()
Convenience method for accessing the UsdShadeNodeDefAPI functionality for this prim.

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

static Define()
classmethod Define(stage, path) -> PluginLight
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) -> PluginLight
Return a UsdLuxPluginLight 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:
UsdLuxPluginLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetNodeDefAPI() → NodeDefAPI
Convenience method for accessing the UsdShadeNodeDefAPI functionality
for this prim.
One can also construct a UsdShadeNodeDefAPI directly from a UsdPrim.

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.UsdLux.PluginLightFilter
Light filter that provides properties that allow it to identify an
external SdrShadingNode definition, through UsdShadeNodeDefAPI, that
can be provided to render delegates without the need to provide a
schema definition for the light filter’s type.
Plugin Lights and Light Filters
Methods:

Define
classmethod Define(stage, path) -> PluginLightFilter

Get
classmethod Get(stage, path) -> PluginLightFilter

GetNodeDefAPI()
Convenience method for accessing the UsdShadeNodeDefAPI functionality for this prim.

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

static Define()
classmethod Define(stage, path) -> PluginLightFilter
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) -> PluginLightFilter
Return a UsdLuxPluginLightFilter 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:
UsdLuxPluginLightFilter(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetNodeDefAPI() → NodeDefAPI
Convenience method for accessing the UsdShadeNodeDefAPI functionality
for this prim.
One can also construct a UsdShadeNodeDefAPI directly from a UsdPrim.

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.UsdLux.PortalLight
A rectangular portal in the local XY plane that guides sampling of a
dome light. Transmits light in the -Z direction. The rectangle is 1
unit in length.
Methods:

Define
classmethod Define(stage, path) -> PortalLight

Get
classmethod Get(stage, path) -> PortalLight

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

static Define()
classmethod Define(stage, path) -> PortalLight
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) -> PortalLight
Return a UsdLuxPortalLight 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:
UsdLuxPortalLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

static GetSchemaAttributeNames()
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]
Return a vector of names of all pre-declared attributes for this
schema class and all its ancestor classes.
Does not include attributes that may be authored by custom/extended
methods of the schemas involved.

Parameters
includeInherited (bool) – 

class pxr.UsdLux.RectLight
Light emitted from one side of a rectangle. The rectangle is centered
in the XY plane and emits light along the -Z axis. The rectangle is 1
unit in length in the X and Y axis. In the default position, a texture
file’s min coordinates should be at (+X, +Y) and max coordinates at
(-X, -Y).
Methods:

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

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

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

Define
classmethod Define(stage, path) -> RectLight

Get
classmethod Get(stage, path) -> RectLight

GetHeightAttr()
Height of the rectangle, in the local Y axis.

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

GetTextureFileAttr()
A color texture to use on the rectangle.

GetWidthAttr()
Width of the rectangle, in the local X axis.

CreateHeightAttr(defaultValue, writeSparsely) → Attribute
See GetHeightAttr() , 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) – 

CreateTextureFileAttr(defaultValue, writeSparsely) → Attribute
See GetTextureFileAttr() , 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) – 

CreateWidthAttr(defaultValue, writeSparsely) → Attribute
See GetWidthAttr() , and also Create vs Get Property Methods for when
to use Get vs Create.
If specified, author defaultValue as the attribute’s default,
sparsely (when it makes sense to do so) if writeSparsely is
true - the default for writeSparsely is false .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

static Define()
classmethod Define(stage, path) -> RectLight
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) -> RectLight
Return a UsdLuxRectLight 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:
UsdLuxRectLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetHeightAttr() → Attribute
Height of the rectangle, in the local Y axis.
Declaration
float inputs:height = 1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

static GetSchemaAttributeNames()
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]
Return a vector of names of all pre-declared attributes for this
schema class and all its ancestor classes.
Does not include attributes that may be authored by custom/extended
methods of the schemas involved.

Parameters
includeInherited (bool) – 

GetTextureFileAttr() → Attribute
A color texture to use on the rectangle.
Declaration
asset inputs:texture:file
C++ Type
SdfAssetPath
Usd Type
SdfValueTypeNames->Asset

GetWidthAttr() → Attribute
Width of the rectangle, in the local X axis.
Declaration
float inputs:width = 1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

class pxr.UsdLux.ShadowAPI
Controls to refine a light’s shadow behavior. These are non-physical
controls that are valuable for visual lighting work.
Methods:

Apply
classmethod Apply(prim) -> ShadowAPI

CanApply
classmethod CanApply(prim, whyNot) -> bool

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

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

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

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

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

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

Get
classmethod Get(stage, path) -> ShadowAPI

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]

GetShadowColorAttr()
The color of shadows cast by the light.

GetShadowDistanceAttr()
The maximum distance shadows are cast.

GetShadowEnableAttr()
Enables shadows to be cast by this light.

GetShadowFalloffAttr()
The near distance at which shadow falloff begins.

GetShadowFalloffGammaAttr()
A gamma (i.e., exponential) control over shadow strength with linear distance within the falloff zone.

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

ConnectableAPI() → ConnectableAPI
Contructs and returns a UsdShadeConnectableAPI object with this shadow
API prim.
Note that a valid UsdLuxShadowAPI will only return a valid
UsdShadeConnectableAPI if the its prim’s Typed schema type is actually
connectable.

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 shadow API 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 shadow API cannot be connected,
as their value is assumed to be computed externally.

Parameters

name (str) – 
typeName (ValueTypeName) – 

CreateShadowColorAttr(defaultValue, writeSparsely) → Attribute
See GetShadowColorAttr() , 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) – 

CreateShadowDistanceAttr(defaultValue, writeSparsely) → Attribute
See GetShadowDistanceAttr() , 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) – 

CreateShadowEnableAttr(defaultValue, writeSparsely) → Attribute
See GetShadowEnableAttr() , 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) – 

CreateShadowFalloffAttr(defaultValue, writeSparsely) → Attribute
See GetShadowFalloffAttr() , 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) – 

CreateShadowFalloffGammaAttr(defaultValue, writeSparsely) → Attribute
See GetShadowFalloffGammaAttr() , 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) -> ShadowAPI
Return a UsdLuxShadowAPI 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:
UsdLuxShadowAPI(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]
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) – 

GetShadowColorAttr() → Attribute
The color of shadows cast by the light.
This is a non-physical control. The default is to cast black shadows.
Declaration
color3f inputs:shadow:color = (0, 0, 0)
C++ Type
GfVec3f
Usd Type
SdfValueTypeNames->Color3f

GetShadowDistanceAttr() → Attribute
The maximum distance shadows are cast.
The default value (-1) indicates no limit.
Declaration
float inputs:shadow:distance = -1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetShadowEnableAttr() → Attribute
Enables shadows to be cast by this light.
Declaration
bool inputs:shadow:enable = 1
C++ Type
bool
Usd Type
SdfValueTypeNames->Bool

GetShadowFalloffAttr() → Attribute
The near distance at which shadow falloff begins.
The default value (-1) indicates no falloff.
Declaration
float inputs:shadow:falloff = -1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetShadowFalloffGammaAttr() → Attribute
A gamma (i.e., exponential) control over shadow strength with linear
distance within the falloff zone.
This requires the use of shadowDistance and shadowFalloff.
Declaration
float inputs:shadow:falloffGamma = 1
C++ Type
float
Usd Type
SdfValueTypeNames->Float

class pxr.UsdLux.ShapingAPI
Controls for shaping a light’s emission.
Methods:

Apply
classmethod Apply(prim) -> ShapingAPI

CanApply
classmethod CanApply(prim, whyNot) -> bool

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

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

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

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

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

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

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

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

Get
classmethod Get(stage, path) -> ShapingAPI

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]

GetShapingConeAngleAttr()
Angular limit off the primary axis to restrict the light spread.

GetShapingConeSoftnessAttr()
Controls the cutoff softness for cone angle.

GetShapingFocusAttr()
A control to shape the spread of light.

GetShapingFocusTintAttr()
Off-axis color tint.

GetShapingIesAngleScaleAttr()
Rescales the angular distribution of the IES profile.

GetShapingIesFileAttr()
An IES (Illumination Engineering Society) light profile describing the angular distribution of light.

GetShapingIesNormalizeAttr()
Normalizes the IES profile so that it affects the shaping of the light while preserving the overall energy output.

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

ConnectableAPI() → ConnectableAPI
Contructs and returns a UsdShadeConnectableAPI object with this
shaping API prim.
Note that a valid UsdLuxShapingAPI will only return a valid
UsdShadeConnectableAPI if the its prim’s Typed schema type is actually
connectable.

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 shaping API 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 shaping API cannot be connected,
as their value is assumed to be computed externally.

Parameters

name (str) – 
typeName (ValueTypeName) – 

CreateShapingConeAngleAttr(defaultValue, writeSparsely) → Attribute
See GetShapingConeAngleAttr() , 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) – 

CreateShapingConeSoftnessAttr(defaultValue, writeSparsely) → Attribute
See GetShapingConeSoftnessAttr() , 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) – 

CreateShapingFocusAttr(defaultValue, writeSparsely) → Attribute
See GetShapingFocusAttr() , 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) – 

CreateShapingFocusTintAttr(defaultValue, writeSparsely) → Attribute
See GetShapingFocusTintAttr() , 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) – 

CreateShapingIesAngleScaleAttr(defaultValue, writeSparsely) → Attribute
See GetShapingIesAngleScaleAttr() , 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) – 

CreateShapingIesFileAttr(defaultValue, writeSparsely) → Attribute
See GetShapingIesFileAttr() , 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) – 

CreateShapingIesNormalizeAttr(defaultValue, writeSparsely) → Attribute
See GetShapingIesNormalizeAttr() , 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) -> ShapingAPI
Return a UsdLuxShapingAPI 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:
UsdLuxShapingAPI(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]
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) – 

GetShapingConeAngleAttr() → Attribute
Angular limit off the primary axis to restrict the light spread.
Declaration
float inputs:shaping:cone:angle = 90
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetShapingConeSoftnessAttr() → Attribute
Controls the cutoff softness for cone angle.
TODO: clarify semantics
Declaration
float inputs:shaping:cone:softness = 0
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetShapingFocusAttr() → Attribute
A control to shape the spread of light.
Higher focus values pull light towards the center and narrow the
spread. Implemented as an off-axis cosine power exponent. TODO:
clarify semantics
Declaration
float inputs:shaping:focus = 0
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetShapingFocusTintAttr() → Attribute
Off-axis color tint.
This tints the emission in the falloff region. The default tint is
black. TODO: clarify semantics
Declaration
color3f inputs:shaping:focusTint = (0, 0, 0)
C++ Type
GfVec3f
Usd Type
SdfValueTypeNames->Color3f

GetShapingIesAngleScaleAttr() → Attribute
Rescales the angular distribution of the IES profile.
TODO: clarify semantics
Declaration
float inputs:shaping:ies:angleScale = 0
C++ Type
float
Usd Type
SdfValueTypeNames->Float

GetShapingIesFileAttr() → Attribute
An IES (Illumination Engineering Society) light profile describing the
angular distribution of light.
Declaration
asset inputs:shaping:ies:file
C++ Type
SdfAssetPath
Usd Type
SdfValueTypeNames->Asset

GetShapingIesNormalizeAttr() → Attribute
Normalizes the IES profile so that it affects the shaping of the light
while preserving the overall energy output.
Declaration
bool inputs:shaping:ies:normalize = 0
C++ Type
bool
Usd Type
SdfValueTypeNames->Bool

class pxr.UsdLux.SphereLight
Light emitted outward from a sphere.
Methods:

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

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

Define
classmethod Define(stage, path) -> SphereLight

Get
classmethod Get(stage, path) -> SphereLight

GetRadiusAttr()
Radius of the sphere.

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

GetTreatAsPointAttr()
A hint that this light can be treated as a'point'light (effectively, a zero-radius sphere) by renderers that benefit from non-area lighting.

CreateRadiusAttr(defaultValue, writeSparsely) → Attribute
See GetRadiusAttr() , 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) – 

CreateTreatAsPointAttr(defaultValue, writeSparsely) → Attribute
See GetTreatAsPointAttr() , and also Create vs Get Property Methods
for when to use Get vs Create.
If specified, author defaultValue as the attribute’s default,
sparsely (when it makes sense to do so) if writeSparsely is
true - the default for writeSparsely is false .

Parameters

defaultValue (VtValue) – 
writeSparsely (bool) – 

static Define()
classmethod Define(stage, path) -> SphereLight
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) -> SphereLight
Return a UsdLuxSphereLight 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:
UsdLuxSphereLight(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

GetRadiusAttr() → Attribute
Radius of the sphere.
Declaration
float inputs:radius = 0.5
C++ Type
float
Usd Type
SdfValueTypeNames->Float

static GetSchemaAttributeNames()
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]
Return a vector of names of all pre-declared attributes for this
schema class and all its ancestor classes.
Does not include attributes that may be authored by custom/extended
methods of the schemas involved.

Parameters
includeInherited (bool) – 

GetTreatAsPointAttr() → Attribute
A hint that this light can be treated as a’point’light (effectively, a
zero-radius sphere) by renderers that benefit from non-area lighting.
Renderers that only support area lights can disregard this.
Declaration
bool treatAsPoint = 0
C++ Type
bool
Usd Type
SdfValueTypeNames->Bool

class pxr.UsdLux.Tokens
Attributes:

angular

automatic

collectionFilterLinkIncludeRoot

collectionLightLinkIncludeRoot

collectionShadowLinkIncludeRoot

consumeAndContinue

consumeAndHalt

cubeMapVerticalCross

cylinderLight

diskLight

distantLight

domeLight

extent

filterLink

geometry

geometryLight

guideRadius

ignore

independent

inputsAngle

inputsColor

inputsColorTemperature

inputsDiffuse

inputsEnableColorTemperature

inputsExposure

inputsHeight

inputsIntensity

inputsLength

inputsNormalize

inputsRadius

inputsShadowColor

inputsShadowDistance

inputsShadowEnable

inputsShadowFalloff

inputsShadowFalloffGamma

inputsShapingConeAngle

inputsShapingConeSoftness

inputsShapingFocus

inputsShapingFocusTint

inputsShapingIesAngleScale

inputsShapingIesFile

inputsShapingIesNormalize

inputsSpecular

inputsTextureFile

inputsTextureFormat

inputsWidth

latlong

lightFilterShaderId

lightFilters

lightLink

lightList

lightListCacheBehavior

lightMaterialSyncMode

lightShaderId

materialGlowTintsLight

meshLight

mirroredBall

noMaterialResponse

orientToStageUpAxis

portalLight

portals

rectLight

shadowLink

sphereLight

treatAsLine

treatAsPoint

volumeLight

angular = 'angular'

automatic = 'automatic'

collectionFilterLinkIncludeRoot = 'collection:filterLink:includeRoot'

collectionLightLinkIncludeRoot = 'collection:lightLink:includeRoot'

collectionShadowLinkIncludeRoot = 'collection:shadowLink:includeRoot'

consumeAndContinue = 'consumeAndContinue'

consumeAndHalt = 'consumeAndHalt'

cubeMapVerticalCross = 'cubeMapVerticalCross'

cylinderLight = 'CylinderLight'

diskLight = 'DiskLight'

distantLight = 'DistantLight'

domeLight = 'DomeLight'

extent = 'extent'

filterLink = 'filterLink'

geometry = 'geometry'

geometryLight = 'GeometryLight'

guideRadius = 'guideRadius'

ignore = 'ignore'

independent = 'independent'

inputsAngle = 'inputs:angle'

inputsColor = 'inputs:color'

inputsColorTemperature = 'inputs:colorTemperature'

inputsDiffuse = 'inputs:diffuse'

inputsEnableColorTemperature = 'inputs:enableColorTemperature'

inputsExposure = 'inputs:exposure'

inputsHeight = 'inputs:height'

inputsIntensity = 'inputs:intensity'

inputsLength = 'inputs:length'

inputsNormalize = 'inputs:normalize'

inputsRadius = 'inputs:radius'

inputsShadowColor = 'inputs:shadow:color'

inputsShadowDistance = 'inputs:shadow:distance'

inputsShadowEnable = 'inputs:shadow:enable'

inputsShadowFalloff = 'inputs:shadow:falloff'

inputsShadowFalloffGamma = 'inputs:shadow:falloffGamma'

inputsShapingConeAngle = 'inputs:shaping:cone:angle'

inputsShapingConeSoftness = 'inputs:shaping:cone:softness'

inputsShapingFocus = 'inputs:shaping:focus'

inputsShapingFocusTint = 'inputs:shaping:focusTint'

inputsShapingIesAngleScale = 'inputs:shaping:ies:angleScale'

inputsShapingIesFile = 'inputs:shaping:ies:file'

inputsShapingIesNormalize = 'inputs:shaping:ies:normalize'

inputsSpecular = 'inputs:specular'

inputsTextureFile = 'inputs:texture:file'

inputsTextureFormat = 'inputs:texture:format'

inputsWidth = 'inputs:width'

latlong = 'latlong'

lightFilterShaderId = 'lightFilter:shaderId'

lightFilters = 'light:filters'

lightLink = 'lightLink'

lightList = 'lightList'

lightListCacheBehavior = 'lightList:cacheBehavior'

lightMaterialSyncMode = 'light:materialSyncMode'

lightShaderId = 'light:shaderId'

materialGlowTintsLight = 'materialGlowTintsLight'

meshLight = 'MeshLight'

mirroredBall = 'mirroredBall'

noMaterialResponse = 'noMaterialResponse'

orientToStageUpAxis = 'orientToStageUpAxis'

portalLight = 'PortalLight'

portals = 'portals'

rectLight = 'RectLight'

shadowLink = 'shadowLink'

sphereLight = 'SphereLight'

treatAsLine = 'treatAsLine'

treatAsPoint = 'treatAsPoint'

volumeLight = 'VolumeLight'

class pxr.UsdLux.VolumeLightAPI
This is the preferred API schema to apply to Volume type prims when
adding light behaviors to a volume. At its base, this API schema has
the built-in behavior of applying LightAPI to the volume and
overriding the default materialSyncMode to allow the emission/glow of
the bound material to affect the color of the light. But, it
additionally serves as a hook for plugins to attach additional
properties to”volume lights”through the creation of API schemas which
are authored to auto-apply to VolumeLightAPI.
Auto applied API schemas
Methods:

Apply
classmethod Apply(prim) -> VolumeLightAPI

CanApply
classmethod CanApply(prim, whyNot) -> bool

Get
classmethod Get(stage, path) -> VolumeLightAPI

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

static Apply()
classmethod Apply(prim) -> VolumeLightAPI
Applies this single-apply API schema to the given prim .
This information is stored by adding”VolumeLightAPI”to the token-
valued, listOp metadata apiSchemas on the prim.
A valid UsdLuxVolumeLightAPI object is returned upon success. An
invalid (or empty) UsdLuxVolumeLightAPI object is returned upon
failure. See UsdPrim::ApplyAPI() for conditions resulting in failure.
UsdPrim::GetAppliedSchemas()
UsdPrim::HasAPI()
UsdPrim::CanApplyAPI()
UsdPrim::ApplyAPI()
UsdPrim::RemoveAPI()

Parameters
prim (Prim) – 

static CanApply()
classmethod CanApply(prim, whyNot) -> bool
Returns true if this single-apply API schema can be applied to the
given prim .
If this schema can not be a applied to the prim, this returns false
and, if provided, populates whyNot with the reason it can not be
applied.
Note that if CanApply returns false, that does not necessarily imply
that calling Apply will fail. Callers are expected to call CanApply
before calling Apply if they want to ensure that it is valid to apply
a schema.
UsdPrim::GetAppliedSchemas()
UsdPrim::HasAPI()
UsdPrim::CanApplyAPI()
UsdPrim::ApplyAPI()
UsdPrim::RemoveAPI()

Parameters

prim (Prim) – 
whyNot (str) – 

static Get()
classmethod Get(stage, path) -> VolumeLightAPI
Return a UsdLuxVolumeLightAPI 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:
UsdLuxVolumeLightAPI(stage->GetPrimAtPath(path));

Parameters

stage (Stage) – 
path (Path) – 

static GetSchemaAttributeNames()
classmethod GetSchemaAttributeNames(includeInherited) -> list[TfToken]
Return a vector of names of all pre-declared attributes for this
schema class and all its ancestor classes.
Does not include attributes that may be authored by custom/extended
methods of the schemas involved.

Parameters
includeInherited (bool) – 

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