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Taxonomy Categories:
Member Functions:
Interface Category:
API.
Inherits From:
TTransferMode
Inherited By:
None.
Purpose:
TGrayDstAtopTransferMode is a concrete class, derived from TTransferMode, for applying the destination atop compositing operation using a grayscale. (The source and destination colors need not be grayscale, but the resulting color is always a gray.) In the destination atop transfer mode, the destination is placed over the source, but only where the source is not completely transparent. If the source color is completely transparent (alpha =0.0), the resultant color is a completely transparent white. Otherwise, if the destination color is completely transparent, the resultant color is determined by the source only. Otherwise, the resultant transparency value is determined by the source only, and the resultant gray value is determined by 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.
- TGrayDstAtopTransferMode ()
- TGrayDstAtopTransferMode (const TGrayDstAtopTransferMode &)
Interface Category:
API.
Purpose:
- Default constructor.
- Copy constructor.
Calling Context:
- Called by the stream-in operators. You can also call this constructor directly.
- Called to copy an object.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual ~ TGrayDstAtopTransferMode ()
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.
virtual void GetResultingColor (const TColor & sourceColor, const TColor & destColor, TColor & resultingColor) const
Interface Category:
API.
Purpose:
Places the destination over the source, but only where the source is not completely transparent. If the source color is completely transparent (alpha =0.0), the resultant color is a completely transparent white. Otherwise, if the destination color is completely transparent, the resultant color is determined by the source only. Otherwise, the resultant transparency value is determined by the source only, and the resultant gray value is determined by both the source and the destination. The resultant grayscale color is returned in a TColor object.
Calling Context:
Call this function directly.
Parameters:
- const TColor & sourceColor -The source color to replaced.
- const TColor & destColor -The destination color to modify.
- TColor & resultingColor -The resultant grayscale color, returned in a TColor Object.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
static void GetDstAtopResult (const TGrayColor & sourceColor, const TGrayColor & destColor, TGrayColor & resultingColor)
Interface Category:
API.
Purpose:
Places the destination over the source, but only where the source is not completely transparent. If the source color is completely transparent (alpha =0.0), the resultant color is a completely transparent white. Otherwise, if the destination color is completely transparent, the resultant color is determined by the source only. Otherwise, the resultant transparency value is determined by the source only, and the resultant gray value is determined by both the source and the destination. The resultant grayscale color is returned in a TGrayColor object.
Calling Context:
Call this function directly.
Parameters:
- const TGrayColor & sourceColor -The source color to replace.
- const TGrayColor & destColor -The destination color to modify.
- TGrayColor & resultingColor -The resultant grayscale color, returned in a TGrayColor object.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
TGrayDstAtopTransferMode & operator =(const TGrayDstAtopTransferMode & 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.
virtual TStream & operator >>=(TStream & towhere) const
Interface Category:
API.
Purpose:
Stream-out operator.
Calling Context:
Called to stream out data.
Parameters:
- TStream & towhere -The stream that the object streams itself out to.
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.
virtual TStream & operator <<= (TStream & fromwhere)
Interface Category:
API.
Purpose:
Stream-in operator.
Calling Context:
Called to stream in data.
Parameters:
- TStream & fromwhere -The stream that the object streams itself in from.
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.
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 kGrayDstAtopTransferMode.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
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