Class: TGrayDstOutTransferMode

Declaration: GrayTransferModes.h

Taxonomy Categories:

Member Functions:


Interface Category:

API.

Inherits From:

TTransferMode

Inherited By:

None.

Purpose:

TGrayDstOutTransferMode is a concrete class, derived from TTransferMode, for applying the source outside compositing operation using a grayscale. (The source and destination colors need not be grayscale, but the resulting color is always a gray.) The result of the destination outside operation contains only the destination pixels that are outside the source area. If the source color is completely transparent (alpha =0.0), the resultant color is determined by the destination. If the source is completely opaque (alpha =1.0), or if the destination color is completely transparent, the resulting color is a completely transparent white. Otherwise, the resultant gray value is determined by the destination color only, and the resultant transparency is a combination of the source's and destination's transparency values.

Instantiation:

Allocate on the heap or the stack.

Deriving Classes:

None.

Concurrency:

Not multithread safe.

Resource Use:

No special requirements.

Member Function: TGrayDstOutTransferMode::TGrayDstOutTransferMode

  1. TGrayDstOutTransferMode ()
  2. TGrayDstOutTransferMode (const TGrayDstOutTransferMode &)

Interface Category:

API.

Purpose:

  1. Default constructor.
  2. Copy constructor.

Calling Context:

  1. Called by the stream-in operators. You can also call this constructor directly.
  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: TGrayDstOutTransferMode::~TGrayDstOutTransferMode

virtual ~ TGrayDstOutTransferMode ()

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: TGrayDstOutTransferMode::GetResultingColor

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

Interface Category:

API.

Purpose:

Replaces the source color with the destination color, taking into account the transparency value of the two colors. If the source color is completely transparent (alpha =0.0), the resultant color is determined by the destination. If the source is completely opaque (alpha =1.0), or if the destination color is completely transparent, the resulting color is a completely transparent white. Otherwise, the resultant gray value is determined by the destination color only, and the resultant transparency is a combination of the source's and destination's transparency values. The resulting color is 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: TGrayDstOutTransferMode::GetDstOutResult

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

Interface Category:

API.

Purpose:

Replaces the source color with the destination color, taking into account the transparency value of the two colors. If the source color is completely transparent (alpha =0.0), the resultant color is determined by the destination. If the source is completely opaque (alpha =1.0), or if the destination color is completely transparent, the resulting color is a completely transparent white. Otherwise, the resultant gray value is determined by the destination color only, and the resultant transparency is a combination of the source's and destination's transparency values. The resulting color is returned in a TGrayColor 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: TGrayDstOutTransferMode::operator=

TGrayDstOutTransferMode & operator =(const TGrayDstOutTransferMode & 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: TGrayDstOutTransferMode::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: TGrayDstOutTransferMode::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: TGrayDstOutTransferMode::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 kGrayDstOutTransferMode.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.
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