UsdMediaAssetPreviewsAPI Class Reference

#include <assetPreviewsAPI.h>

Inheritance diagram for UsdMediaAssetPreviewsAPI:

Classes
struct	Thumbnails

Public Member Functions
	UsdMediaAssetPreviewsAPI (const UsdPrim &prim=UsdPrim())
	UsdMediaAssetPreviewsAPI (const UsdSchemaBase &schemaObj)
virtual USDMEDIA_API	~UsdMediaAssetPreviewsAPI ()
	Destructor. More...
USDMEDIA_API bool	GetDefaultThumbnails (Thumbnails *defaultThumbnails) const
USDMEDIA_API void	SetDefaultThumbnails (const Thumbnails &defaultThumbnails) const
USDMEDIA_API void	ClearDefaultThumbnails () const
Public Member Functions inherited from UsdAPISchemaBase
	UsdAPISchemaBase (const UsdPrim &prim=UsdPrim())
	UsdAPISchemaBase (const UsdSchemaBase &schemaObj)
virtual USD_API	~UsdAPISchemaBase ()=0
	Destructor. More...
Public Member Functions inherited from UsdSchemaBase
bool	IsConcrete () const
bool	IsTyped () const
bool	IsAPISchema () const
	Returns whether this is an API schema or not. More...
bool	IsAppliedAPISchema () const
bool	IsMultipleApplyAPISchema () const
UsdSchemaKind	GetSchemaKind () const
	Returns the kind of schema this class is. More...
USD_API	UsdSchemaBase (const UsdPrim &prim=UsdPrim())
	Construct and store prim as the held prim. More...
USD_API	UsdSchemaBase (const UsdSchemaBase &otherSchema)
	Construct and store for the same prim held by otherSchema. More...
virtual USD_API	~UsdSchemaBase ()
	Destructor. More...
USD_API	operator bool () const
UsdPrim	GetPrim () const
	Return this schema object's held prim. More...
SdfPath	GetPath () const
	Shorthand for GetPrim()->GetPath(). More...
USD_API const UsdPrimDefinition *	GetSchemaClassPrimDefinition () const

Static Public Member Functions
static USDMEDIA_API const TfTokenVector &	GetSchemaAttributeNames (bool includeInherited=true)
static USDMEDIA_API UsdMediaAssetPreviewsAPI	Get (const UsdStagePtr &stage, const SdfPath &path)
static USDMEDIA_API bool	CanApply (const UsdPrim &prim, std::string *whyNot=nullptr)
static USDMEDIA_API UsdMediaAssetPreviewsAPI	Apply (const UsdPrim &prim)
static USDMEDIA_API UsdMediaAssetPreviewsAPI	GetAssetDefaultPreviews (const std::string &layerPath)
static USDMEDIA_API UsdMediaAssetPreviewsAPI	GetAssetDefaultPreviews (const SdfLayerHandle &layer)
Static Public Member Functions inherited from UsdAPISchemaBase
static USD_API const TfTokenVector &	GetSchemaAttributeNames (bool includeInherited=true)
Static Public Member Functions inherited from UsdSchemaBase
static const TfTokenVector &	GetSchemaAttributeNames (bool includeInherited=true)

Static Public Attributes
static const UsdSchemaKind	schemaKind = UsdSchemaKind::SingleApplyAPI
Static Public Attributes inherited from UsdAPISchemaBase
static const UsdSchemaKind	schemaKind = UsdSchemaKind::AbstractBase
Static Public Attributes inherited from UsdSchemaBase
static const UsdSchemaKind	schemaKind = UsdSchemaKind::AbstractBase

Protected Member Functions
USDMEDIA_API UsdSchemaKind	_GetSchemaKind () const override
Protected Member Functions inherited from UsdAPISchemaBase
	UsdAPISchemaBase (const UsdPrim &prim, const TfToken &instanceName)
	UsdAPISchemaBase (const UsdSchemaBase &schemaObj, const TfToken &instanceName)
const TfToken &	_GetInstanceName () const
USD_API bool	_IsCompatible () const override
Protected Member Functions inherited from UsdSchemaBase
virtual UsdSchemaKind	_GetSchemaType () const
const TfType &	_GetType () const
USD_API UsdAttribute	_CreateAttr (TfToken const &attrName, SdfValueTypeName const &typeName, bool custom, SdfVariability variability, VtValue const &defaultValue, bool writeSparsely) const

Friends
class	UsdSchemaRegistry

Additional Inherited Members
Static Protected Member Functions inherited from UsdAPISchemaBase
static USD_API TfTokenVector	_GetMultipleApplyInstanceNames (const UsdPrim &prim, const TfType &schemaType)

Detailed Description

AssetPreviewsAPI is the interface for authoring and accessing precomputed, lightweight previews of assets. It is an applied schema, which means that an arbitrary number of prims on a stage can have the schema applied and therefore can contain previews; however, to access a stage's "default" previews, one consults the stage's defaultPrim.

AssetPreviewsAPI supports the following kinds of previews:

• thumbnails : a set of pre-rendered images of the asset. There is no prescribed size for thumbnail images, but care should be taken to ensure their inclusion does not substantially increase the overall size of an asset, as, for example, when packaged into USDZ.

Although the UsdMediaAssetPreviewsAPI class can be used to interrogate any prim, no query in the API will succeed unless the schema has been applied to the prim. This schema deals only with asset paths, and clients wishing to directly consume the returned data must do so by retrieving an ArAsset from the session's ArAssetResolver.

The schema defines no properties or metadata fallback values. Rather, Asset Previews are encoded as part of a prim's assetInfo metadata. A default thumbnail image would look like: ```

1. assetInfo = {
2. dictionary previews = {
3. dictionary thumbnails = {
4. dictionary default = {
5. asset defaultImage = .jpg@
6. }
7. }
8. }
9. } ```

Definition at line 94 of file assetPreviewsAPI.h.

Constructor & Destructor Documentation

UsdMediaAssetPreviewsAPI::UsdMediaAssetPreviewsAPI ( const UsdPrim &  prim = UsdPrim() )

inlineexplicit

Construct a UsdMediaAssetPreviewsAPI on UsdPrim prim . Equivalent to UsdMediaAssetPreviewsAPI::Get(prim.GetStage(), prim.GetPath()) for a valid prim, but will not immediately throw an error for an invalid prim

Definition at line 106 of file assetPreviewsAPI.h.

UsdMediaAssetPreviewsAPI::UsdMediaAssetPreviewsAPI ( const UsdSchemaBase &  schemaObj )

inlineexplicit

Construct a UsdMediaAssetPreviewsAPI on the prim held by schemaObj . Should be preferred over UsdMediaAssetPreviewsAPI(schemaObj.GetPrim()), as it preserves SchemaBase state.

Definition at line 114 of file assetPreviewsAPI.h.

virtual USDMEDIA_API UsdMediaAssetPreviewsAPI::~UsdMediaAssetPreviewsAPI ( )

virtual

Destructor.

Member Function Documentation

USDMEDIA_API UsdSchemaKind UsdMediaAssetPreviewsAPI::_GetSchemaKind ( ) const

overrideprotectedvirtual

Returns the kind of schema this class belongs to.

See Also

UsdSchemaKind

Reimplemented from UsdAPISchemaBase.

static USDMEDIA_API UsdMediaAssetPreviewsAPI UsdMediaAssetPreviewsAPI::Apply ( const UsdPrim &  prim )

static

Applies this single-apply API schema to the given prim. This information is stored by adding "AssetPreviewsAPI" to the token-valued, listOp metadata apiSchemas on the prim.

Returns

A valid UsdMediaAssetPreviewsAPI object is returned upon success. An invalid (or empty) UsdMediaAssetPreviewsAPI object is returned upon failure. See UsdPrim::ApplyAPI() for conditions resulting in failure.

See Also

UsdPrim::GetAppliedSchemas()

UsdPrim::HasAPI()

UsdPrim::CanApplyAPI()

UsdPrim::ApplyAPI()

UsdPrim::RemoveAPI()

static USDMEDIA_API bool UsdMediaAssetPreviewsAPI::CanApply ( const UsdPrim &  prim, std::string *  whyNot = nullptr  )

static

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.

See Also

UsdPrim::GetAppliedSchemas()

UsdPrim::HasAPI()

UsdPrim::CanApplyAPI()

UsdPrim::ApplyAPI()

UsdPrim::RemoveAPI()

USDMEDIA_API void UsdMediaAssetPreviewsAPI::ClearDefaultThumbnails

(

)

const

Remove the entire entry for default Thumbnails in the current UsdEditTarget

static USDMEDIA_API UsdMediaAssetPreviewsAPI UsdMediaAssetPreviewsAPI::Get ( const UsdStagePtr &  stage, const SdfPath &  path  )

static

Return a UsdMediaAssetPreviewsAPI 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:

UsdMediaAssetPreviewsAPI(stage->GetPrimAtPath(path));

static USDMEDIA_API UsdMediaAssetPreviewsAPI UsdMediaAssetPreviewsAPI::GetAssetDefaultPreviews ( const std::string &  layerPath )

static

Return a schema object that can be used to interrogate previews for the default prim of the stage constructed from layerPath.

The schema object will create and retain a minimal stage required for interrogation. This is equivalent to: GetAssetDefaultPreviews(SdfLayer::FindOrOpen(layerPath))

static USDMEDIA_API UsdMediaAssetPreviewsAPI UsdMediaAssetPreviewsAPI::GetAssetDefaultPreviews ( const SdfLayerHandle &  layer )

static

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

USDMEDIA_API bool UsdMediaAssetPreviewsAPI::GetDefaultThumbnails

(

Thumbnails *

defaultThumbnails

)

const

Fetch the default Thumbnails data, returning true if data was successfully fetched.

static USDMEDIA_API const TfTokenVector& UsdMediaAssetPreviewsAPI::GetSchemaAttributeNames ( bool  includeInherited = true )

static

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.

USDMEDIA_API void UsdMediaAssetPreviewsAPI::SetDefaultThumbnails

(

const Thumbnails &

defaultThumbnails

)

const

Author the default thumbnails dictionary from the provided Thumbnails data

Friends And Related Function Documentation

friend class UsdSchemaRegistry

friend

Definition at line 192 of file assetPreviewsAPI.h.

Member Data Documentation

const UsdSchemaKind UsdMediaAssetPreviewsAPI::schemaKind = UsdSchemaKind::SingleApplyAPI

static

Compile time constant representing what kind of schema this class is.

See Also

UsdSchemaKind

Definition at line 100 of file assetPreviewsAPI.h.

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The documentation for this class was generated from the following file:

• pxr/usd/usdMedia/assetPreviewsAPI.h