UsdHydra module

Summary: The UsdHydra module.

---

Classes:

GenerativeProceduralAPI	This API extends and configures the core UsdProcGenerativeProcedural schema defined within usdProc for use with hydra generative procedurals as defined within hdGp.
Tokens

class pxr.UsdHydra.GenerativeProceduralAPI

This API extends and configures the core UsdProcGenerativeProcedural schema defined within usdProc for use with hydra generative procedurals as defined within hdGp.

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

Methods:

Apply	classmethod Apply(prim) -> GenerativeProceduralAPI
CanApply	classmethod CanApply(prim, whyNot) -> bool
CreateProceduralSystemAttr(defaultValue, ...)	See GetProceduralSystemAttr() , and also Create vs Get Property Methods for when to use Get vs Create.
CreateProceduralTypeAttr(defaultValue, ...)	See GetProceduralTypeAttr() , and also Create vs Get Property Methods for when to use Get vs Create.
Get	classmethod Get(stage, path) -> GenerativeProceduralAPI
GetProceduralSystemAttr()	This value should correspond to a configured instance of HdGpGenerativeProceduralResolvingSceneIndex which will evaluate the procedural.
GetProceduralTypeAttr()	The registered name of a HdGpGenerativeProceduralPlugin to be executed.
GetSchemaAttributeNames	classmethod GetSchemaAttributeNames(includeInherited) -> list[str]

static Apply()

classmethod Apply(prim) -> GenerativeProceduralAPI

Applies this single-apply API schema to the given prim .

This information is stored by adding”HydraGenerativeProceduralAPI”to the token-valued, listOp metadata apiSchemas on the prim.

A valid UsdHydraGenerativeProceduralAPI object is returned upon success. An invalid (or empty) UsdHydraGenerativeProceduralAPI 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)

CreateProceduralSystemAttr(

defaultValue,

writeSparsely,

) → Attribute

See GetProceduralSystemAttr() , 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)

CreateProceduralTypeAttr(

defaultValue,

writeSparsely,

) → Attribute

See GetProceduralTypeAttr() , 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) -> GenerativeProceduralAPI

Return a UsdHydraGenerativeProceduralAPI 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:

UsdHydraGenerativeProceduralAPI(stage->GetPrimAtPath(path));

Parameters:

• stage (Stage)

• path (Path)

GetProceduralSystemAttr() → Attribute

This value should correspond to a configured instance of HdGpGenerativeProceduralResolvingSceneIndex which will evaluate the procedural.

The default value of”hydraGenerativeProcedural”matches the equivalent default of HdGpGenerativeProceduralResolvingSceneIndex. Multiple instances of the scene index can be used to determine where within a scene index chain a given procedural will be evaluated.

Declaration

token proceduralSystem ="hydraGenerativeProcedural"

C++ Type

TfToken

Usd Type

SdfValueTypeNames->Token

GetProceduralTypeAttr() → Attribute

The registered name of a HdGpGenerativeProceduralPlugin to be executed.

Declaration

token primvars:hdGp:proceduralType

C++ Type

TfToken

Usd Type

SdfValueTypeNames->Token

static GetSchemaAttributeNames()

classmethod GetSchemaAttributeNames(includeInherited) -> list[str]

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.UsdHydra.Tokens

Attributes:

HwPrimvar_1
HwPtexTexture_1
HwUvTexture_1
black
clamp
displayLookBxdf
faceIndex
faceOffset
frame
hydraGenerativeProcedural
infoFilename
infoVarname
linear
linearMipmapLinear
linearMipmapNearest
magFilter
minFilter
mirror
nearest
nearestMipmapLinear
nearestMipmapNearest
primvarsHdGpProceduralType
proceduralSystem
repeat
textureMemory
useMetadata
uv
wrapS
wrapT

HwPrimvar_1 = 'HwPrimvar_1'

HwPtexTexture_1 = 'HwPtexTexture_1'

HwUvTexture_1 = 'HwUvTexture_1'

black = 'black'

clamp = 'clamp'

displayLookBxdf = 'displayLook:bxdf'

faceIndex = 'faceIndex'

faceOffset = 'faceOffset'

frame = 'frame'

hydraGenerativeProcedural = 'hydraGenerativeProcedural'

infoFilename = 'inputs:file'

infoVarname = 'inputs:varname'

linear = 'linear'

linearMipmapLinear = 'linearMipmapLinear'

linearMipmapNearest = 'linearMipmapNearest'

magFilter = 'magFilter'

minFilter = 'minFilter'

mirror = 'mirror'

nearest = 'nearest'

nearestMipmapLinear = 'nearestMipmapLinear'

nearestMipmapNearest = 'nearestMipmapNearest'

primvarsHdGpProceduralType = 'primvars:hdGp:proceduralType'

proceduralSystem = 'proceduralSystem'

repeat = 'repeat'

textureMemory = 'textureMemory'

useMetadata = 'useMetadata'

uv = 'uv'

wrapS = 'wrapS'

wrapT = 'wrapT'