Cairo::FontOptions Class Reference

The font options specify how fonts should be rendered. More...

#include <cairomm/fontoptions.h>

Public Types
enum class	HintStyle {   DEFAULT = CAIRO_HINT_STYLE_DEFAULT ,   NONE = CAIRO_HINT_STYLE_NONE ,   SLIGHT = CAIRO_HINT_STYLE_SLIGHT ,   MEDIUM = CAIRO_HINT_STYLE_MEDIUM ,   FULL = CAIRO_HINT_STYLE_FULL }
	Specifies the type of hinting to do on font outlines. More...
enum class	HintMetrics {   DEFAULT = CAIRO_HINT_METRICS_DEFAULT ,   OFF = CAIRO_HINT_METRICS_OFF ,   ON = CAIRO_HINT_METRICS_ON }
	Specifies whether to hint font metrics; hinting font metrics means quantizing them so that they are integer values in device space. More...
typedef cairo_font_options_t	cobject

Public Member Functions
	FontOptions ()
	FontOptions (cairo_font_options_t *cobject, bool take_ownership=false)
	FontOptions (const FontOptions & src)
virtual	~FontOptions ()
FontOptions &	operator= (const FontOptions & src)
bool	operator== (const FontOptions & src) const
void	merge (const FontOptions & other)
	Merges non-default options from other into this, replacing existing values. More...
unsigned long	hash () const
	Compute a hash for the font options object; this value will be useful when storing an object containing a FontOptions in a hash table. More...
void	set_antialias (Antialias antialias)
	Sets the antialiasing mode for the font options object. More...
Antialias	get_antialias () const
	Gets the antialiasing mode for the font options object. More...
void	set_subpixel_order (SubpixelOrder subpixel_order)
	Sets the subpixel order for the font options object. More...
SubpixelOrder	get_subpixel_order () const
	Gets the subpixel order for the font options object. More...
void	set_hint_style (HintStyle hint_style)
	Sets the hint style for font outlines for the font options object. More...
HintStyle	get_hint_style () const
	Gets the hint style for font outlines for the font options object. More...
void	set_hint_metrics (HintMetrics hint_metrics)
	Sets the metrics hinting mode for the font options object. More...
HintMetrics	get_hint_metrics () const
	Gets the metrics hinting mode for the font options object. More...
cobject *	cobj ()
const cobject *	cobj () const

Protected Attributes
cobject *	m_cobject

Detailed Description

The font options specify how fonts should be rendered.

Most of the time the font options implied by a surface are just right and do not need any changes, but for pixel-based targets tweaking font options may result in superior output on a particular display.

Member Typedef Documentation

cobject

typedef cairo_font_options_t Cairo::FontOptions::cobject

Member Enumeration Documentation

HintMetrics

enum class Cairo::FontOptions::HintMetrics

strong

Specifies whether to hint font metrics; hinting font metrics means quantizing them so that they are integer values in device space.

Doing this improves the consistency of letter and line spacing, however it also means that text will be laid out differently at different zoom factors.

Enumerator
DEFAULT	Hint metrics in the default manner for the font backend and target device.
OFF	Do not hint font metrics.
ON	Hint font metrics.

HintStyle

enum class Cairo::FontOptions::HintStyle

strong

Specifies the type of hinting to do on font outlines.

Hinting is the process of fitting outlines to the pixel grid in order to improve the appearance of the result. Since hinting outlines involves distorting them, it also reduces the faithfulness to the original outline shapes. Not all of the outline hinting styles are supported by all font backends.

New entries may be added in future versions.

Enumerator
DEFAULT	Use the default hint style for font backend and target device.
NONE	Do not hint outlines.
SLIGHT	Hint outlines slightly to improve contrast while retaining food fidelity to the original shapes.
MEDIUM	Hint outlines with medium strength giving a compromise between fidelity to the original shapes and contrast.
FULL	Hint outlines to maximize contrast.

Constructor & Destructor Documentation

FontOptions() [1/3]

Cairo::FontOptions::FontOptions

(

)

FontOptions() [2/3]

Cairo::FontOptions::FontOptions ( cairo_font_options_t *  cobject, bool  take_ownership = false  )

explicit

FontOptions() [3/3]

Cairo::FontOptions::FontOptions

(

const FontOptions &

src

)

~FontOptions()

virtual Cairo::FontOptions::~FontOptions ( )

virtual

Member Function Documentation

cobj() [1/2]

cobject * Cairo::FontOptions::cobj ( )

inline

cobj() [2/2]

const cobject * Cairo::FontOptions::cobj ( ) const

inline

get_antialias()

Antialias Cairo::FontOptions::get_antialias

(

)

const

Gets the antialiasing mode for the font options object.

Returns

the antialiasing mode

get_hint_metrics()

HintMetrics Cairo::FontOptions::get_hint_metrics

(

)

const

Gets the metrics hinting mode for the font options object.

See the documentation for HintMetrics for full details.

Return value: the metrics hinting mode for the font options object.

get_hint_style()

HintStyle Cairo::FontOptions::get_hint_style

(

)

const

Gets the hint style for font outlines for the font options object.

See the documentation for HintStyle for full details.

Returns

the hint style for the font options object.

get_subpixel_order()

SubpixelOrder Cairo::FontOptions::get_subpixel_order

(

)

const

Gets the subpixel order for the font options object.

See the documentation for SubpixelOrder for full details.

Returns

the subpixel order for the font options object.

hash()

unsigned long Cairo::FontOptions::hash

(

)

const

Compute a hash for the font options object; this value will be useful when storing an object containing a FontOptions in a hash table.

Returns

the hash value for the font options object. The return value can be cast to a 32-bit type if a 32-bit hash value is needed.

merge()

void Cairo::FontOptions::merge

(

const FontOptions &

other

)

Merges non-default options from other into this, replacing existing values.

This operation can be thought of as somewhat similar to compositing other onto this with the operation of OPERATION_OVER.

Parameters

other

another FontOptions

operator=()

FontOptions & Cairo::FontOptions::operator=

(

const FontOptions &

src

)

operator==()

bool Cairo::FontOptions::operator==

(

const FontOptions &

src

)

const

set_antialias()

void Cairo::FontOptions::set_antialias

(

Antialias

antialias

)

Sets the antialiasing mode for the font options object.

This specifies the type of antialiasing to do when rendering text.

Parameters

antialias

the new antialiasing mode.

set_hint_metrics()

void Cairo::FontOptions::set_hint_metrics

(

HintMetrics

hint_metrics

)

Sets the metrics hinting mode for the font options object.

This controls whether metrics are quantized to integer values in device units. See the documentation for HintMetrics for full details.

Parameters

hint_metrics

the new metrics hinting mode.

set_hint_style()

void Cairo::FontOptions::set_hint_style

(

HintStyle

hint_style

)

Sets the hint style for font outlines for the font options object.

This controls whether to fit font outlines to the pixel grid, and if so, whether to optimize for fidelity or contrast. See the documentation for HintStyle for full details.

Parameters

hint_style

the new hint style.

set_subpixel_order()

void Cairo::FontOptions::set_subpixel_order

(

SubpixelOrder

subpixel_order

)

Sets the subpixel order for the font options object.

The subpixel order specifies the order of color elements within each pixel on the display device when rendering with an antialiasing mode of Cairo::ANTIALIAS_SUBPIXEL. See the documentation for SubpixelOrder for full details.

Parameters

subpixel_order

the new subpixel order.

Member Data Documentation

m_cobject

cobject* Cairo::FontOptions::m_cobject

protected

---

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

• cairomm/fontoptions.h