Class: TScaleCanvasGraphicCmd

Declaration: CanvasCommands.h

Taxonomy Categories:

Member Functions:

Interface Category:

API.

Inherits From:

TChangeCanvasGraphicCmd

Inherited By:

None.

Purpose:

Scales all the canvas graphics in the target selection.

Instantiation:

Allocate on the heap or the stack.

Deriving Classes:

Intended to be used as is but can also be derived.

Concurrency:

Not multithread safe.

Resource Use:

No special requirements.

Member Function: TScaleCanvasGraphicCmd::TScaleCanvasGraphicCmd

TScaleCanvasGraphicCmd ()
TScaleCanvasGraphicCmd (const TGPoint & centerOfScale)
TScaleCanvasGraphicCmd (const TGPoint & scaleFactor, const TGPoint & centerOfScale)
TScaleCanvasGraphicCmd (const TScaleCanvasGraphicCmd &)

Interface Category:

API.

Purpose:

Default constructor, assumes TGPoint(0,0) as the center of scale.
Constructs from a center of scale.
Constructs from a scale factor and a center of scale.
Copy constructor.

Calling Context:

Called by the stream-in operators and to create a new command.
Called to create a new command.
Called to create a new command.
Called to copy an object.

Parameters:

Takes no parameters.
const TGPoint & centerOfScale -The center of scale to use.
const TGPoint & scaleFactor -The scale factor to use.
const TScaleCanvasGraphicCmd & -Another command to copy.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

The center of scale must remain constant throughout the execution of an incremental scale command.

Member Function: TScaleCanvasGraphicCmd::~TScaleCanvasGraphicCmd

virtual ~ TScaleCanvasGraphicCmd ()

Interface Category:

API.

Purpose:

Destructor.

Calling Context:

Called to destroy an object.

Parameters:

Takes no parameters.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TScaleCanvasGraphicCmd::operator>>=

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

Interface Category:

API.

Purpose:

Stream-out operator.

Calling Context:

Called to stream out data.

Parameters:

TStream & -The stream the object is streamed 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.

Member Function: TScaleCanvasGraphicCmd::operator<<=

virtual TStream & operator <<= (TStream &)

Interface Category:

API.

Purpose:

Stream-in operator.

Calling Context:

Called to stream in data.

Parameters:

TStream & -The stream the object is streamed in from.

Return Value:

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

Exceptions:

Throws a TStandardException(kStreamBadVersion,0) when streaming in a version other than kOriginalVersion. Passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TScaleCanvasGraphicCmd::operator=

TScaleCanvasGraphicCmd & operator =(const TScaleCanvasGraphicCmd &)

Interface Category:

API.

Purpose:

Assignment operator.

Calling Context:

Called when an object is assigned to another compatible object.

Parameters:

const TScaleCanvasGraphicCmd & -The object to be copied.

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: TScaleCanvasGraphicCmd::SetScaleFactor

virtual void SetScaleFactor (const TGPoint &)

Interface Category:

API.

Purpose:

Sets the scale factor used for scaling graphics when the command is done.

Calling Context:

Typically called by the same client that creates the command.

Parameters:

const TGPoint & -The scale factor to use.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

Can be called multiple times after command construction for incremental commands. A point specifies the scale factor in the x- and y-directions.

Member Function: TScaleCanvasGraphicCmd::BeginChange

virtual void BeginChange (MCanvasRepresentation &, MCanvasGraphic &)

Interface Category:

API.

Purpose:

Scales the specified canvas graphic and saves undo information to later restore the graphic in UndoChange.

Calling Context:

Called by TChangeCanvasGraphicCmd::HandleDoBegin.

Parameters:

MCanvasRepresentation & -The representation that the canvas graphic is in.
MCanvasGraphic & -The canvas graphic to change.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

TCanvasGraphicAssociationsWith is used to save the entire graphic for undo.

Member Function: TScaleCanvasGraphicCmd::ContinueChange

virtual void ContinueChange (MCanvasRepresentation &, MCanvasGraphic &)

Interface Category:

API.

Purpose:

Scales the specified canvas graphic.

Calling Context:

Called by TChangeCanvasGraphicCmd::HandleDoIncrement.

Parameters:

MCanvasRepresentation & -The representation that the canvas graphic is in.
MCanvasGraphic & -The canvas graphic to change.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TScaleCanvasGraphicCmd::UndoChange

virtual void UndoChange (MCanvasRepresentation &, MCanvasGraphic &)

Interface Category:

API.

Purpose:

Undoes the prior changes to a specified canvas graphic and saves redo information to later restore the graphic in RedoChange.

Calling Context:

Called for each canvas graphic in the target selection by TChangeCanvasGraphicCmd::HandleUndo.

Parameters:

MCanvasRepresentation & -The representation that the canvas graphic is in.
MCanvasGraphic & -The canvas graphic for which to undo the change.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

TCanvasGraphicAssociationsWith is used to save the entire graphic for undo and redo. Undo is accomplished by calling MCanvasRepresentation::Swap to swap the saved graphic for the current one.

Member Function: TScaleCanvasGraphicCmd::RedoChange

virtual void RedoChange (MCanvasRepresentation &, MCanvasGraphic &)

Interface Category:

API.

Purpose:

Redoes changes to a specified canvas graphic and saves undo information to later restore the graphic in UndoChange.

Calling Context:

Called for each canvas graphic in the target selection by TChangeCanvasGraphicCmd::HandleRedo.

Parameters:

MCanvasRepresentation & -The representation that the canvas graphic is in.
MCanvasGraphic & -The canvas graphic for which to redo the change.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

TCanvasGraphicAssociationsWith is used to save the entire graphic for undo and redo. Redo is accomplished by calling MCanvasRepresentation::Swap to swap the saved graphic for the current one.

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