Class: TGraySrcAroundTransferMode

Declaration: GrayTransferModes.h

Taxonomy Categories:

Member Functions:

Interface Category:

API.

Inherits From:

TTransferMode

Inherited By:

None.

Purpose:

TGraySrcAroundTransferMode is a concrete class, derived from TTransferMode, for applying the source around compositing operation using a grayscale. (The source and destination colors need not be grayscale, but the resulting color is always a gray.) You can think of source around as placing the source image behind rather than over the destination. If the destination color is completely transparent (that is, if its alpha value is 0.0), this transfer mode copies the grayscale equivalent of the source color to the destination. If the destination color is completely opaque (alpha =1.0), the destination is unchanged. If the destination's alpha value is between 0 and 1, the resultant gray value and transparency are computed by taking into account both the source and the destination.

Instantiation:

Allocate on the heap or the stack.

Deriving Classes:

None.

Concurrency:

Not multithread safe.

Resource Use:

No special requirements.

Member Function: TGraySrcAroundTransferMode::TGraySrcAroundTransferMode

  1. TGraySrcAroundTransferMode ()
  2. TGraySrcAroundTransferMode (const TGraySrcAroundTransferMode &)

Interface Category:

API.

Purpose:

  1. Default constructor.
  2. Copy constructor.

Calling Context:

  1. Called by the stream-in operators and as the default constructor.
  2. Called to copy an object.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TGraySrcAroundTransferMode::~TGraySrcAroundTransferMode

virtual ~ TGraySrcAroundTransferMode ()

Interface Category:

API.

Purpose:

Destructor.

Calling Context:

Called to destroy an object.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TGraySrcAroundTransferMode::GetResultingColor

virtual void GetResultingColor (const TColor & sourceColor, const TColor & destColor, TColor & resultingColor) const

Interface Category:

API.

Purpose:

If the destination color is completely transparent (that is, if its alpha value is 0.0),. copies the grayscale equivalent of the source color to the destination. If the destination color is completely opaque (alpha =1.0), the destination is unchanged. If the destination's alpha value is between 0 and 1, the resultant gray value and transparency are computed by taking into account both the source and the destination. The resulting color is a grayscale color returned in a TColor object.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TGraySrcAroundTransferMode::GetSrcAroundResult

static void GetSrcAroundResult (const TGrayColor & sourceColor, const TGrayColor & destColor, TGrayColor & resultingColor)

Interface Category:

API.

Purpose:

If the destination color is completely transparent (that is, if its alpha value is 0.0), copies the grayscale equivalent of the source color to the destination. If the destination color is completely opaque (alpha =1.0), the destination is unchanged. If the destination's alpha value is between 0 and 1, the resultant gray value and transparency are computed by taking into account both the source and the destination. The resulting color is a grayscale color returned in a TColor object.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TGraySrcAroundTransferMode::operator=

TGraySrcAroundTransferMode & operator =(const TGraySrcAroundTransferMode & source)

Interface Category:

API.

Purpose:

Assignment operator.

Calling Context:

Call this function by using the operator in an assignment statement.

Parameters:

Return Value:

A non-const reference to the left-hand side object.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TGraySrcAroundTransferMode::operator>>=

virtual TStream & operator >>=(TStream & towhere) const

Interface Category:

API.

Purpose:

Stream-out operator.

Calling Context:

Called to stream out data.

Parameters:

Return Value:

Returns a reference to the stream the object streams itself out to.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TGraySrcAroundTransferMode::operator<<=

virtual TStream & operator <<= (TStream & fromwhere)

Interface Category:

API.

Purpose:

Stream-in operator.

Calling Context:

Called to stream in data.

Parameters:

Return Value:

Returns a reference to the stream the object streams itself in from.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TGraySrcAroundTransferMode::TemporaryTypeID

virtual ETransferModeClassID TemporaryTypeID () const

Interface Category:

API.

Purpose:

Returns the type of transfer mode this class represents.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns an ETransferModeClassID with value kGraySrcAroundTransferMode.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.
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