TOpenFontSpec Class Reference

#include <openfont.h>

Link against: fntstr.lib

class TOpenFontSpec : public TOpenFontFaceAttribBase

Inherits from

TOpenFontSpec
- TOpenFontFaceAttribBase

Public Member Enumerations
enum	anonymous { EAlgorithmicBold, EDropShadow, EOutline }

Public Member Functions
	TOpenFontSpec()
	TOpenFontSpec(const TFontSpec &)
TInt	ApplyRatio(TInt &, TInt, TInt)
TInt	ApplyRatio(TInt32 &, TInt, TInt)
TGlyphBitmapType	BitmapType()
IMPORT_C void	CompensateForAspectRatio(TInt, TInt)
IMPORT_C void	CompensateForAspectRatio(const MGraphicsDeviceMap &)
TUint32	Effects()
IMPORT_C void	GetTFontSpec(TFontSpec &)
TInt	Height()
TBool	IsCompensationForAspectRatioNeeded(TInt, TInt)
IMPORT_C TBool	IsEffectOn(FontEffect::TEffect)
TFontPrintPosition	PrintPosition()
IMPORT_C TInt	ScriptTypeForMetrics()
IMPORT_C void	SetAttrib(const TOpenFontFaceAttribBase &)
void	SetBitmapType(TGlyphBitmapType)
void	SetEffects(TUint32)
IMPORT_C void	SetEffects(FontEffect::TEffect, TBool)
void	SetHeight(TInt)
IMPORT_C void	SetScriptTypeForMetrics(TLanguage)
void	SetSlantFactor(TInt32)
void	SetWidthFactor(TInt32)
TInt32	SlantFactor()
TInt32	WidthFactor()
TBool	operator!=(const TOpenFontSpec &)
IMPORT_C void	operator=(const TFontSpec &)
TBool	operator==(const TOpenFontSpec &)

Inherited Attributes
	TOpenFontFaceAttribBase::iCoverage
	TOpenFontFaceAttribBase::iName
	TOpenFontFaceAttribBase::iReserved
	TOpenFontFaceAttribBase::iStyle

Inherited Enumerations
	TOpenFontFaceAttribBase:@46
	TOpenFontFaceAttribBase:@47
	TOpenFontFaceAttribBase:@48
	TOpenFontFaceAttribBase:@49
	TOpenFontFaceAttribBase:@57
	TOpenFontFaceAttribBase:@58
	TOpenFontFaceAttribBase:@59
	TOpenFontFaceAttribBase:@60

Inherited Functions
	TOpenFontFaceAttribBase::Coverage()const
	TOpenFontFaceAttribBase::HasCJK()const
	TOpenFontFaceAttribBase::HasCyrillic()const
	TOpenFontFaceAttribBase::HasGreek()const
	TOpenFontFaceAttribBase::HasHangul()const
	TOpenFontFaceAttribBase::HasKana()const
	TOpenFontFaceAttribBase::HasLatin()const
	TOpenFontFaceAttribBase::IsBold()const
	TOpenFontFaceAttribBase::IsItalic()const
	TOpenFontFaceAttribBase::IsMonoWidth()const
	TOpenFontFaceAttribBase::IsSerif()const
	TOpenFontFaceAttribBase::IsSymbol()const
	TOpenFontFaceAttribBase::Name()const
	TOpenFontFaceAttribBase::SetBold(TBool)
	TOpenFontFaceAttribBase::SetCoverage(TUint,TUint,TUint,TUint)
	TOpenFontFaceAttribBase::SetItalic(TBool)
	TOpenFontFaceAttribBase::SetMonoWidth(TBool)
	TOpenFontFaceAttribBase::SetName(const TDesC &)
	TOpenFontFaceAttribBase::SetSerif(TBool)
	TOpenFontFaceAttribBase::TOpenFontFaceAttribBase()
	TOpenFontFaceAttribBase::operator==(const TOpenFontFaceAttribBase &)const

Detailed Description

Font specification allowing more attributes to be specified than TFontSpec.

In addition to the attributes specified by TFontSpec, this font specification allows stretching and slanting in the x dimension, and other algorithmic effects. This is used to correct for non-square pixels, and to allow algorithmic slanting and bold. The width factor and slant factor transform any point (x,y) to (x iWidthFactor + y * iSlantFactor,y). The width and slant factors are 16.16 fixed-point numbers.

The font specification also provides access to information about the scripts which are supported by the font. This information is not always reliable, because it may be incorrectly specified, or not specified at all, by some font manufacturers.

Member Enumeration Documentation

Enum anonymous

Algorithmic effects flags.

These can be combined using an OR operation.

WARNING: Enum for internal and partner use ONLY. Compatibility is not guaranteed in future releases.

DeprecatedUse FontEffect::TEffect instead.

Enumerator	Value	Description
EAlgorithmicBold	1	Font is algorithmic bold.
EDropShadow	2	Font has a drop shadow.
EOutline	4	Font is an outline font.

Constructor & Destructor Documentation

TOpenFontSpec ( )

IMPORT_C

TOpenFontSpec

(

)

Default C++ constructor setting height to 16 pixels or twips, width factor to 1 (65536 in 16.16 format), slant factor to 0 (no slant), effects to ENone, symbol to 0 (assuming EScriptNone = 0), print position to EPrintPosNormal.

TOpenFontSpec ( const TFontSpec & )

IMPORT_C

TOpenFontSpec

(

const TFontSpec &

aFontSpec

)

C++ constructor taking a reference to a TFontSpec.

This object's members are initialised from the values of the aFontSpec parameter.

Parameter	Description
aFontSpec	The font specification used to initialise this font specification.

Member Function Documentation

ApplyRatio ( TInt &, TInt, TInt )

TInt	ApplyRatio	(	TInt &	aValue,
			TInt	aNumerator,
			TInt	aDenominator
		)	[static]

Multiplies aValue by aNumerator/aDenominator but using TInt64's to avoid any overflows. Returns ETrue if the final result has an overflow.

ApplyRatio ( TInt32 &, TInt, TInt )

TInt	ApplyRatio	(	TInt32 &	aValue,
			TInt	aNumerator,
			TInt	aDenominator
		)	[static]

Same as above function but this takes a TInt32 not a TInt

BitmapType ( )

TGlyphBitmapType

BitmapType

(

)

const [inline]

Gets the anti-aliasing setting for the font, as set by SetBitmapType().

Returns: Indicates whether or not the font should be drawn using anti-aliasing.

CompensateForAspectRatio ( TInt, TInt )

IMPORT_C void	CompensateForAspectRatio	(	TInt	aPixelWidth,
			TInt	aPixelHeight
		)

Adjust the width factor and slant factor to suit a pixel aspect ratio.

Parameter	Description
aPixelWidth	The pixel width, in the same units as aPixelHeight.
aPixelHeight	The pixel height, in the same units as aPixelWidth.

CompensateForAspectRatio ( const MGraphicsDeviceMap & )

IMPORT_C void

CompensateForAspectRatio

(

const MGraphicsDeviceMap &

aMap

)

Adjust the width factor and slant factor to suit a pixel aspect ratio stored in a MGraphicsDeviceMap derived object.

Parameter	Description
aMap	The MGraphicsDeviceMap defining the pixel aspect ratio.

Effects ( )

TUint32

Effects

(

)

const [inline]

Gets the font effects flags. Because the flags encoded in the Effects are anonymous, the return value should only be tested for the specific bits that are of interest, and never tested as a whole.

GetTFontSpec ( TFontSpec & )

IMPORT_C void

GetTFontSpec

(

TFontSpec &

aFontSpec

)

const

Gets the TFontSpec corresponding to this Open Font System font specification.

Parameter	Description
aFontSpec	On return, contains the TFontSpec corresponding to this font specification.

Height ( )

TInt

Height

(

)

const [inline]

Gets the height of the font.

IsCompensationForAspectRatioNeeded ( TInt, TInt )

TBool	IsCompensationForAspectRatioNeeded	(	TInt	aPixelWidth,
			TInt	aPixelHeight
		)	[static]

The pixel width and height are used to derive a ratio, and so can be in any units. Aspect ratios differing by less than 1/1000 are treated as 1:1.

IsEffectOn ( FontEffect::TEffect )

IMPORT_C TBool

IsEffectOn

(

FontEffect::TEffect

aEffect

)

const

Checks if a font effect is on.

Parameter	Description
aEffect	The font effect to be checked.

PrintPosition ( )

TFontPrintPosition

PrintPosition

(

)

const [inline]

Gets the print position.

Returns: The print position.

ScriptTypeForMetrics ( )

IMPORT_C TInt

ScriptTypeForMetrics

(

)

const

Gets the script which the font metrics calculation will be based on.

Returns: The script.

SetAttrib ( const TOpenFontFaceAttribBase & )

IMPORT_C void

SetAttrib

(

const TOpenFontFaceAttribBase &

aAttrib

)

Sets the font attributes.

Parameter	Description
aAttrib	The font attributes.

SetBitmapType ( TGlyphBitmapType )

void

SetBitmapType

(

TGlyphBitmapType

aBitmapType

)

[inline]

Sets whether the font should be drawn using anti-aliasing. If set, this value overrides the default setting (set by CFbsTypefaceStore::SetDefaultBitmapType()) for this font.

Anti-aliasing can only be used for scalable fonts. There is currently no anti-aliasing support for bitmapped fonts.

Parameter	Description
aBitmapType	Indicates whether or not the font should be drawn using anti-aliasing.

SetEffects ( TUint32 )

void

SetEffects

(

TUint32

aEffects

)

[inline]

Sets the font effects flags. Prior to calling this routine, the value from Effects() should be read, and its flags modified as required, before passing them back in.

SetEffects ( FontEffect::TEffect, TBool )

IMPORT_C void	SetEffects	(	FontEffect::TEffect	aEffect,
			TBool	aOn
		)

Sets a font effect to the given state.

Parameter	Description
aEffect	The font effect to be set.
aOn	True represents on, otherwise off.

SetHeight ( TInt )

void

SetHeight

(

TInt

aHeight

)

[inline]

Sets the font's height.

Parameter	Description
aHeight	The font's height, in pixels or twips.

SetScriptTypeForMetrics ( TLanguage )

IMPORT_C void

SetScriptTypeForMetrics

(

TLanguage

aLanguage

)

Specifies the script which font metrics calculation will be based on.

Parameter	Description
aLanguage	The language used to derive the required script.

SetSlantFactor ( TInt32 )

void

SetSlantFactor

(

TInt32

aSlantFactor

)

[inline]

Sets the algorithmic slant factor.

Note: The slant factor is used to create an italic effect for characters which do not have an italic glyph in the typeface. When slanting is active, pixel x co-ordinates are shifted by a factor relative to the y co-ordinate (i.e. x = x + y x slant factor).

The slant factor is a 32 bit, 16.16 fixed-point number. This means that the first 16 bits are treated as a whole number, and the second 16 as the fractional part. e.g. if aSlantFactor=0, there is no slant. If aSlantFactor=65536 this is equivalent to an integer slant value of 1, which causes a 45 degree slant on the character.

Parameter	Description
aSlantFactor	The slant factor as a 16.16 fixed-point number.

SetWidthFactor ( TInt32 )

void

SetWidthFactor

(

TInt32

aWidthFactor

)

[inline]

Sets the algorithmic width factor.

The width factor is multiplied by the pixel's x position to get the new position, causing characters to become wider or narrower. A width factor of 1 (65536 in 16.16 fixed-point number format) should be used if the character width is not to be changed.

Parameter	Description
aWidthFactor	The algorithmic width factor as a 16.16 fixed-point number.

SlantFactor ( )

TInt32

SlantFactor

(

)

const [inline]

Gets the algorithmic slant factor.

WidthFactor ( )

TInt32

WidthFactor

(

)

const [inline]

Gets the algorithmic width factor.

operator!= ( const TOpenFontSpec & )

TBool

operator!=

(

const TOpenFontSpec &

aOpenFontSpec

)

const

operator= ( const TFontSpec & )

IMPORT_C void

operator=

(

const TFontSpec &

aFontSpec

)

Assignment operator.

Parameter	Description
aFontSpec	The old-style font specification to copy into this font specification.

operator== ( const TOpenFontSpec & )

TBool

operator==

(

const TOpenFontSpec &

aFontSpec

)

const [inline]

Compares this and another open font specification. Compares all the properties of the two fonts.

Parameter	Description
aFontSpec	The open font specification to compare with this one.

Returns: ETrue if all values are equal, EFalse if not.