Class: TGraySubtractiveTransferMode

Declaration: GrayTransferModes.h

Taxonomy Categories:

Member Functions:


Interface Category:

API.

Inherits From:

TTransferMode

Inherited By:

None.

Purpose:

TGraySubtractiveTransferMode is a concrete class, derived from TTransferMode, that yields a grayscale result given a source color and a destination color. The resulting grayscale value is equal to the destination's grayscale value minus the source's. (The source and destination need not be grayscale colors, but the resulting color is always a gray.) Similarly, the transparency value of the result is that of the destination minus that of the source. If the result of a subtraction is a negative number, the value is set to zero instead.

Instantiation:

Allocate on the heap or the stack.

Deriving Classes:

None.

Concurrency:

Not multithread safe.

Resource Use:

No special requirements.

Member Function: TGraySubtractiveTransferMode::TGraySubtractiveTransferMode

  1. TGraySubtractiveTransferMode ()
  2. TGraySubtractiveTransferMode (const TGraySubtractiveTransferMode &)

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: TGraySubtractiveTransferMode::~TGraySubtractiveTransferMode

virtual ~ TGraySubtractiveTransferMode ()

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: TGraySubtractiveTransferMode::GetResultingColor

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

Interface Category:

API.

Purpose:

Returns the grayscale value equal to the destination's grayscale value minus the source's. Similarly, the transparency value of the resulting color is equal to the destination's transparency value minus the source's. All parameters are specified as TColor objects, even though only the grayscale value is used.

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: TGraySubtractiveTransferMode::GetSubtractiveResult

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

Interface Category:

API.

Purpose:

Returns the grayscale value equal to the destination's grayscale value minus the source's. Similarly, the transparency value of the resulting color is equal to the destination's transparency value minus the source's. All parameters are specified as TGrayColor objects.

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: TGraySubtractiveTransferMode::operator=

TGraySubtractiveTransferMode & operator =(const TGraySubtractiveTransferMode & 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: TGraySubtractiveTransferMode::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: TGraySubtractiveTransferMode::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: TGraySubtractiveTransferMode::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 kGraySubtractiveTransferMode.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.
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