The interface for mapping between twips and device-specific units enriched with facilities to allow zooming. More...

#include <gdi.h>

Inheritance diagram for TZoomFactor:

Public Types
enum	{ EZoomOneToOne =1000 }
	One to one zoom factor. More...

Public Member Functions
IMPORT_C	TZoomFactor ()
	Constructs a default zoom factor object.

IMPORT_C	~TZoomFactor ()
	Destructor.

	TZoomFactor (const MGraphicsDeviceMap *aDevice)
	Constructs a zoom factor object for a specific graphics device map.

	TZoomFactor (const TZoomFactor *aDevice)

IMPORT_C TInt	ZoomFactor () const
	Gets the zoom factor.

IMPORT_C void	SetZoomFactor (TInt aZoomFactor)
	Sets the zoom factor.

void	SetGraphicsDeviceMap (const MGraphicsDeviceMap *aDevice)
	Sets the graphics device map for this zoom factor object.

const MGraphicsDeviceMap *	GraphicsDeviceMap () const
	Gets the graphics device map of this zoom factor object.

IMPORT_C void	SetTwipToPixelMapping (const TSize &aSizeInPixels, const TSize &aSizeInTwips)
	Sets the twips to pixels mapping for the graphics device with which the zoom factor is associated.

IMPORT_C TInt	HorizontalTwipsToPixels (TInt aTwipWidth) const
	Converts a horizontal dimension from twips to pixels.

IMPORT_C TInt	VerticalTwipsToPixels (TInt aTwipHeight) const
	Converts a vertical dimension from twips to pixels.

IMPORT_C TInt	HorizontalPixelsToTwips (TInt aPixelWidth) const
	Converts a horizontal dimension from pixels to twips.

IMPORT_C TInt	VerticalPixelsToTwips (TInt aPixelHeight) const
	Converts a vertical dimension from pixels to twips.

IMPORT_C TInt	GetNearestFontInTwips (CFont *&aFont, const TFontSpec &aFontSpec)

IMPORT_C TInt	GetNearestFontToDesignHeightInTwips (CFont *&aFont, const TFontSpec &aFontSpec)

IMPORT_C TInt	GetNearestFontToMaxHeightInTwips (CFont *&aFont, const TFontSpec &aFontSpec, TInt aMaxHeight)

IMPORT_C void	ReleaseFont (CFont *aFont)
	Releases the specified font.

Public Member Functions inherited from MGraphicsDeviceMap
IMPORT_C	MGraphicsDeviceMap ()
	Default constructor.

virtual IMPORT_C	~MGraphicsDeviceMap ()
	Destructor.

IMPORT_C TPoint	TwipsToPixels (const TPoint &aTwipPoint) const
	Converts a point in twips to a point in pixels.

IMPORT_C TRect	TwipsToPixels (const TRect &aTwipRect) const
	Converts a rectangle in twips to a rectangle in pixels.

IMPORT_C TPoint	PixelsToTwips (const TPoint &aPixelPoint) const
	Converts a point in pixels to a point in twips.

IMPORT_C TRect	PixelsToTwips (const TRect &aPixelRect) const
	Converts a rectangle in pixels to a rectangle in twips.

Detailed Description

The interface for mapping between twips and device-specific units enriched with facilities to allow zooming.

The class is recursive, because a TZoomFactor object can have a MGraphicsDeviceMap (which could itself be a TZoomFactor) in its member data. This allows a zoom factor object to contain another zoom factor object, and is used to allow objects with different zoom factors to be embedded in each other to an arbitrary depth by the application architecture.

API status: Published to all clients. Released API.

Definition at line 4307 of file gdi.h.

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

One to one zoom factor.

Enumerator
EZoomOneToOne

Definition at line 4330 of file gdi.h.

Constructor & Destructor Documentation

◆ TZoomFactor() [1/3]

IMPORT_C TZoomFactor::TZoomFactor ( )

Constructs a default zoom factor object.

Note that a TZoomFactor object cannot be used until a CGraphicsDevice to which it is associated is specified (by SetGraphicsDeviceMap()). Therefore the other constructor is normally used for constructing TZoomFactors. The default constructor function is provided for use in TZoomFactor-derived classes.

(generated from Symbian Developer Library)

◆ ~TZoomFactor()

IMPORT_C TZoomFactor::~TZoomFactor ( )

Destructor.

Frees resources owned by the object, prior to its destruction.

(generated from Symbian Developer Library)

◆ TZoomFactor() [2/3]

TZoomFactor::TZoomFactor ( const MGraphicsDeviceMap * aDevice )

inline

Constructs a zoom factor object for a specific graphics device map.

The graphics map is either directly associated with a particular graphics device itself, or is associated with a hierarchy of device maps whose root map is associated with a particular graphics device.

Parameters

aDevice The graphics device map with which the zoom factor is associated.

(generated from Symbian Developer Library)

◆ TZoomFactor() [3/3]

TZoomFactor::TZoomFactor ( const TZoomFactor * aDevice )

inline

Member Function Documentation

◆ GetNearestFontInTwips()

IMPORT_C TInt TZoomFactor::GetNearestFontInTwips	(	CFont *&	aFont,
		const TFontSpec &	aFontSpec
	)

virtual

Gets the font which is the nearest to the given font specification.

When the font is no longer needed, call @c ReleaseFont().

Note that this deprecated function is replaced by the new @c GetNearestFontToDesignHeightInTwips() 
yielding (virtually) the same result. However clients are strongly encouraged to use the new
@c GetNearestFontToMaxHeightInTwips() function instead. This will guarantee that every 
character within any given text string will fit within the given amount of twips, whereas the design 
height is an aesthetic unit decided by the font designer without strict physical meaning, which 
may result in cropped characters.

@param aFont On return, contains a pointer to the nearest font.
@param aFontSpec The specification of the font to be matched.
@return KErrNone if successful; a system-wide error code otherwise.
@deprecated Use GetNearestFontToDesignHeightInTwips

API status: Published to all clients.

Parameters

aFont	On return, contains a pointer to the nearest font.
aFontSpec	The specification of the font to be matched.

(generated from Symbian Developer Library)

Implements MGraphicsDeviceMap.

◆ GetNearestFontToDesignHeightInTwips()

IMPORT_C TInt TZoomFactor::GetNearestFontToDesignHeightInTwips	(	CFont *&	aFont,
		const TFontSpec &	aFontSpec
	)

virtual

Parameters

aFont	On return, contains a pointer to the nearest font.
aFontSpec	The specification of the font to be matched.

(generated from Symbian Developer Library)

Reimplemented from MGraphicsDeviceMap.

◆ GetNearestFontToMaxHeightInTwips()

IMPORT_C TInt TZoomFactor::GetNearestFontToMaxHeightInTwips	(	CFont *&	aFont,
		const TFontSpec &	aFontSpec,
		TInt	aMaxHeight
	)

virtual

Parameters

aFont	On return, contains a pointer to the nearest font.
aFontSpec	The specification of the font to be matched.
aMaxHeight	The maximum height within which the font must fit. This overrides the height specified in aFontSpec. If maximum height is greater than 1024 pixels, the function returns KErrTooBig. And returns KErrArgument if equals to 1 pixel.

(generated from Symbian Developer Library)

Reimplemented from MGraphicsDeviceMap.

◆ GraphicsDeviceMap()

const MGraphicsDeviceMap * TZoomFactor::GraphicsDeviceMap ( ) const

inline

Gets the graphics device map of this zoom factor object.

(generated from Symbian Developer Library)

◆ HorizontalPixelsToTwips()

IMPORT_C TInt TZoomFactor::HorizontalPixelsToTwips ( TInt aPixels ) const

virtual

Converts a horizontal dimension from pixels to twips.

An implementation is supplied by a derived class.

Parameters

aPixels A horizontal dimension of a device in pixels.

Returns: A horizontal dimension of a device in twips.

Implements MGraphicsDeviceMap.

◆ HorizontalTwipsToPixels()

IMPORT_C TInt TZoomFactor::HorizontalTwipsToPixels ( TInt aTwips ) const

virtual

Converts a horizontal dimension from twips to pixels.

An implementation is supplied by a derived class.

Parameters

aTwips A horizontal dimension of a device in twips.

Returns: A horizontal dimension of a device in pixels.

Implements MGraphicsDeviceMap.

◆ ReleaseFont()

IMPORT_C void TZoomFactor::ReleaseFont ( CFont * aFont )

virtual

Releases the specified font.

It is used to indicate that the specified font is no longer needed for use by the device map. As fonts can be shared between applications, this function does not delete the copy of the font from RAM unless the font was only being used by this particular device map.

An implementation is supplied by a derived class.

Parameters

aFont A pointer to the font to be released.

Implements MGraphicsDeviceMap.

◆ SetGraphicsDeviceMap()

void TZoomFactor::SetGraphicsDeviceMap ( const MGraphicsDeviceMap * aDevice )

inline

Sets the graphics device map for this zoom factor object.

Parameters

aDevice The graphics device map for this TZoomFactor.

(generated from Symbian Developer Library)

◆ SetTwipToPixelMapping()

IMPORT_C void TZoomFactor::SetTwipToPixelMapping	(	const TSize &	aSizeInPixels,
		const TSize &	aSizeInTwips
	)

Sets the twips to pixels mapping for the graphics device with which the zoom factor is associated.

This setting is used by all the twips to pixels and pixels to twips conversion functions.

Parameters

aSizeInPixels	The size of the graphics device area in pixels.
aSizeInTwips	The size of the graphics device area in twips.

(generated from Symbian Developer Library)

◆ SetZoomFactor()

IMPORT_C void TZoomFactor::SetZoomFactor ( TInt aZoomFactor )

Sets the zoom factor.

Parameters

aZoomFactor The desired zoom factor.

(generated from Symbian Developer Library)

◆ VerticalPixelsToTwips()

IMPORT_C TInt TZoomFactor::VerticalPixelsToTwips ( TInt aPixels ) const

virtual

Converts a vertical dimension from pixels to twips.

An implementation is supplied by a derived class.

Parameters

aPixels A vertical dimension of a device in pixels.

Returns: A vertical dimension of a device in twips.

Implements MGraphicsDeviceMap.

◆ VerticalTwipsToPixels()

IMPORT_C TInt TZoomFactor::VerticalTwipsToPixels ( TInt aTwips ) const

virtual

Converts a vertical dimension from twips to pixels.

An implementation is supplied by a derived class.

Parameters

aTwips A vertical dimension of a device in twips.

Returns: A vertical dimension of a device in pixels.

Implements MGraphicsDeviceMap.

◆ ZoomFactor()

IMPORT_C TInt TZoomFactor::ZoomFactor ( ) const

Gets the zoom factor.

(generated from Symbian Developer Library)

The documentation for this class was generated from the following files:

Public Types

Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ anonymous enum

Constructor & Destructor Documentation

◆ TZoomFactor() [1/3]

◆ ~TZoomFactor()

◆ TZoomFactor() [2/3]

◆ TZoomFactor() [3/3]

Member Function Documentation

◆ GetNearestFontInTwips()

◆ GetNearestFontToDesignHeightInTwips()

◆ GetNearestFontToMaxHeightInTwips()

◆ GraphicsDeviceMap()

◆ HorizontalPixelsToTwips()

◆ HorizontalTwipsToPixels()

◆ ReleaseFont()

◆ SetGraphicsDeviceMap()

◆ SetTwipToPixelMapping()

◆ SetZoomFactor()

◆ VerticalPixelsToTwips()

◆ VerticalTwipsToPixels()

◆ ZoomFactor()