AssetPreviewsAPI is the interface for authoring and accessing precomputed, lightweight previews of assets. More...

#include <assetPreviewsAPI.h>

Inheritance diagram for UsdMediaAssetPreviewsAPI:

Classes
struct	Thumbnails
	Thumbnails is a value type that serves as schema to aid in serialization and deserialization of thumbnail images in the assetInfo["thumbnails"] dictionary. More...

Public Member Functions
	UsdMediaAssetPreviewsAPI (const UsdPrim &prim=UsdPrim())
	Construct a UsdMediaAssetPreviewsAPI on UsdPrim `prim` .

	UsdMediaAssetPreviewsAPI (const UsdSchemaBase &schemaObj)
	Construct a UsdMediaAssetPreviewsAPI on the prim held by `schemaObj` .

virtual USDMEDIA_API	~UsdMediaAssetPreviewsAPI ()
	Destructor.

USDMEDIA_API bool	GetDefaultThumbnails (Thumbnails *defaultThumbnails) const
	Fetch the default Thumbnails data, returning `true` if data was successfully fetched.

USDMEDIA_API void	SetDefaultThumbnails (const Thumbnails &defaultThumbnails) const
	Author the default thumbnails dictionary from the provided Thumbnails data.

USDMEDIA_API void	ClearDefaultThumbnails () const
	Remove the entire entry for default Thumbnails in the current UsdEditTarget.

Public Member Functions inherited from UsdAPISchemaBase
	UsdAPISchemaBase (const UsdPrim &prim=UsdPrim())
	Construct a UsdAPISchemaBase on UsdPrim `prim` .

	UsdAPISchemaBase (const UsdSchemaBase &schemaObj)
	Construct a UsdAPISchemaBase on the prim held by `schemaObj` .

virtual USD_API	~UsdAPISchemaBase ()=0
	Destructor.

Public Member Functions inherited from UsdSchemaBase
bool	IsConcrete () const
	Returns whether or not this class corresponds to a concrete instantiable prim type in scene description.

bool	IsTyped () const
	Returns whether or not this class inherits from UsdTyped.

bool	IsAPISchema () const
	Returns whether this is an API schema or not.

bool	IsAppliedAPISchema () const
	Returns whether this is an applied API schema or not.

bool	IsMultipleApplyAPISchema () const
	Returns whether this is an applied API schema or not.

UsdSchemaKind	GetSchemaKind () const
	Returns the kind of schema this class is.

USD_API	UsdSchemaBase (const UsdPrim &prim=UsdPrim())
	Construct and store `prim` as the held prim.

USD_API	UsdSchemaBase (const UsdSchemaBase &otherSchema)
	Construct and store for the same prim held by `otherSchema`.

virtual USD_API	~UsdSchemaBase ()
	Destructor.

UsdPrim	GetPrim () const
	Return this schema object's held prim.

SdfPath	GetPath () const
	Shorthand for GetPrim()->GetPath().

USD_API const UsdPrimDefinition *	GetSchemaClassPrimDefinition () const
	Return the prim definition associated with this schema instance if one exists, otherwise return null.

USD_API	operator bool () const
	Return true if this schema object is compatible with its held prim, false otherwise.

Static Public Member Functions
static USDMEDIA_API const TfTokenVector &	GetSchemaAttributeNames (bool includeInherited=true)
	Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.

static USDMEDIA_API UsdMediaAssetPreviewsAPI	Get (const UsdStagePtr &stage, const SdfPath &path)
	Return a UsdMediaAssetPreviewsAPI holding the prim adhering to this schema at `path` on `stage`.

static USDMEDIA_API bool	CanApply (const UsdPrim &prim, std::string *whyNot=nullptr)
	Returns true if this single-apply API schema can be applied to the given `prim`.

static USDMEDIA_API UsdMediaAssetPreviewsAPI	Apply (const UsdPrim &prim)
	Applies this single-apply API schema to the given `prim`.

static USDMEDIA_API UsdMediaAssetPreviewsAPI	GetAssetDefaultPreviews (const std::string &layerPath)
	Return a schema object that can be used to interrogate previews for the default prim of the stage constructed from `layerPath`.

static USDMEDIA_API UsdMediaAssetPreviewsAPI	GetAssetDefaultPreviews (const SdfLayerHandle &layer)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Static Public Member Functions inherited from UsdAPISchemaBase
static USD_API const TfTokenVector &	GetSchemaAttributeNames (bool includeInherited=true)
	Return a vector of names of all pre-declared attributes for this schema class and all its ancestor classes.

Static Public Member Functions inherited from UsdSchemaBase
static const TfTokenVector &	GetSchemaAttributeNames (bool includeInherited=true)

Static Public Attributes
static const UsdSchemaKind	schemaKind = UsdSchemaKind::SingleApplyAPI
	Compile time constant representing what kind of schema this class is.

Static Public Attributes inherited from UsdAPISchemaBase
static const UsdSchemaKind	schemaKind = UsdSchemaKind::AbstractBase
	Compile time constant representing what kind of schema this class is.

Static Public Attributes inherited from UsdSchemaBase
static const UsdSchemaKind	schemaKind = UsdSchemaKind::AbstractBase
	Compile time constant representing what kind of schema this class is.

Protected Member Functions
USDMEDIA_API UsdSchemaKind	_GetSchemaKind () const override
	Returns the kind of schema this class belongs to.

Protected Member Functions inherited from UsdAPISchemaBase
USD_API UsdSchemaKind	_GetSchemaKind () const override
	Returns the kind of schema this class belongs to.

	UsdAPISchemaBase (const UsdPrim &prim, const TfToken &instanceName)
	Construct a multiple-apply UsdAPISchemaBase on UsdPrim `prim` with the specified `instanceName`.

	UsdAPISchemaBase (const UsdSchemaBase &schemaObj, const TfToken &instanceName)
	Construct a multiple-apply UsdAPISchemaBase on the prim held by `schemaObj` with the given `instanceName`.

const TfToken &	_GetInstanceName () const
	Returns the instance name of the API schema object belonging to a multiple-apply API schema.

USD_API bool	_IsCompatible () const override
	Check whether this APISchema object is valid for the currently held prim.

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)
	Returns a vector of names of API schema objects belonging to a multiple-apply API schema applied to a given prim.

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:

   assetInfo = {
     dictionary previews = {
         dictionary thumbnails = {
             dictionary default = {
                 asset defaultImage = @chair_thumb.jpg@
             }
         }
     }
   }

Definition at line 77 of file assetPreviewsAPI.h.

Constructor & Destructor Documentation

◆ UsdMediaAssetPreviewsAPI() [1/2]

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 89 of file assetPreviewsAPI.h.

◆ UsdMediaAssetPreviewsAPI() [2/2]

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 97 of file assetPreviewsAPI.h.

◆ ~UsdMediaAssetPreviewsAPI()

virtual USDMEDIA_API ~UsdMediaAssetPreviewsAPI ( )

virtual

Destructor.

Member Function Documentation

◆ _GetSchemaKind()

USDMEDIA_API UsdSchemaKind _GetSchemaKind ( ) const

overrideprotectedvirtual

Returns the kind of schema this class belongs to.

See also: UsdSchemaKind

Reimplemented from UsdAPISchemaBase.

◆ Apply()

static USDMEDIA_API 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()

◆ CanApply()

static USDMEDIA_API bool 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()

◆ ClearDefaultThumbnails()

USDMEDIA_API void ClearDefaultThumbnails ( ) const

Remove the entire entry for default Thumbnails in the current UsdEditTarget.

◆ Get()

static USDMEDIA_API 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));

UsdMediaAssetPreviewsAPI

AssetPreviewsAPI is the interface for authoring and accessing precomputed, lightweight previews of as...

Definition: assetPreviewsAPI.h:78

◆ GetAssetDefaultPreviews() [1/2]

static USDMEDIA_API 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.

◆ GetAssetDefaultPreviews() [2/2]

static USDMEDIA_API 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))

◆ GetDefaultThumbnails()

USDMEDIA_API bool GetDefaultThumbnails ( Thumbnails * defaultThumbnails ) const

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

◆ GetSchemaAttributeNames()

static USDMEDIA_API const TfTokenVector & 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.

◆ SetDefaultThumbnails()

USDMEDIA_API void SetDefaultThumbnails ( const Thumbnails & defaultThumbnails ) const

Author the default thumbnails dictionary from the provided Thumbnails data.

Friends And Related Function Documentation

◆ UsdSchemaRegistry

friend class UsdSchemaRegistry

friend

Definition at line 175 of file assetPreviewsAPI.h.

Member Data Documentation

◆ schemaKind

const UsdSchemaKind schemaKind = UsdSchemaKind::SingleApplyAPI

static

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

See also: UsdSchemaKind

Definition at line 83 of file assetPreviewsAPI.h.

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

pxr/usd/usdMedia/assetPreviewsAPI.h

Classes

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Member Functions

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ UsdMediaAssetPreviewsAPI() [1/2]

◆ UsdMediaAssetPreviewsAPI() [2/2]

◆ ~UsdMediaAssetPreviewsAPI()

Member Function Documentation

◆ _GetSchemaKind()

◆ Apply()

◆ CanApply()

◆ ClearDefaultThumbnails()

◆ Get()

◆ GetAssetDefaultPreviews() [1/2]

◆ GetAssetDefaultPreviews() [2/2]

◆ GetDefaultThumbnails()

◆ GetSchemaAttributeNames()

◆ SetDefaultThumbnails()

Friends And Related Function Documentation

◆ UsdSchemaRegistry

Member Data Documentation

◆ schemaKind