Manages a font and properties of a font. More...

#include <font.h>

Classes
struct	FontExtents
	Font extent. More...

struct	TextExtents
	Text extent. More...

Public Types
using	Extent = float

using	Size = float
	Scalar used for font size.

enum class	Slant { normal = 0 , italic = 1 , oblique = 2 }
	Font slants. More...

enum class	Weight { normal = 0 , bold = 1 }
	Font weights. More...

Public Member Functions
	Font ()

	Font (const std::string &face)
	Create a font based on the supplied parameters.

	Font (const std::string &face, Font::Size size, Font::Weight weight=Weight::normal, Font::Slant slant=Slant::normal)
	Create a font based on the supplied parameters.

	Font (const unsigned char *data, size_t len, Font::Size size)
	Create a font from an in-memory font.

	Font (Font::Size size)
	Create a font based on the global default font, but with the specified size.

	Font (Font::Size size, Font::Weight weight)
	Create a font based on the global default font, but with the specified size and weight.

	Font (Font::Slant slant)
	Create a font based on the global default font, but with the specified slant.

	Font (Font::Weight weight)
	Create a font based on the global default font, but with the specified weight.

void	deserialize (const std::string &name, const std::string &value, const Serializer::Attributes &attrs)
	Deserialize.

EGT_NODISCARD Font::FontExtents	extents () const
	Get the font extents based on a default context.

EGT_NODISCARD Font::TextExtents	extents (const std::string &text) const
	Get the text extents based on a default context.

EGT_NODISCARD const std::string &	face () const
	Get the face name the font.

void	face (const std::string &face)
	Set the face of the font.

void	on_screen_resized ()
	Recompute the font size from the screen size but only if it has not been defined by the user.

EGT_NODISCARD const detail::InternalFont &	scaled_font () const
	Generates a FontConfig scaled font instance.

void	serialize (const std::string &name, Serializer &serializer) const
	Serialize to the specified serializer.

EGT_NODISCARD Font::Size	size () const
	Get the size of the font.

void	size (const Font::Size &s)
	Set the size of the font.

EGT_NODISCARD Font::Slant	slant () const
	Get the slant of the font.

void	slant (Font::Slant s)
	Set the slant of the font.

EGT_NODISCARD egt::Size	text_size (const std::string &text) const
	Get the size of a rectangle containing the text, based on a default context.

EGT_NODISCARD Font::Weight	weight () const
	Get the weight of the font.

void	weight (Font::Weight w)
	Set the weight of the font.

Static Public Member Functions
static void	reset_font_cache ()
	Clears any internal font cache.

static void	shutdown_fonts ()
	Basically, this will clear the font cache and shutdown FontConfig which will release all memory allocated by FontConfig.

Static Public Attributes
static constexpr const char *	DEFAULT_FACE = "Free Sans"
	Default font face.

static constexpr Font::Size	DEFAULT_SIZE = 18.f
	Default font size.

static constexpr Font::Slant	DEFAULT_SLANT = Font::Slant::normal
	Default font slant.

static constexpr Font::Weight	DEFAULT_WEIGHT = Font::Weight::normal
	Default font weight.

Protected Member Functions
void	direct_allocate ()

Protected Attributes
const unsigned char *	m_data {nullptr}

std::string	m_face {DEFAULT_FACE}
	Font face name.

size_t	m_len {0}

std::shared_ptr< detail::InternalFont >	m_scaled_font
	Only used when an in-memory font is created.

Font::Size	m_size
	Font size.

Font::Slant	m_slant {DEFAULT_SLANT}
	Font slant.

bool	m_use_default_size {true}
	Use default size.

Font::Weight	m_weight {DEFAULT_WEIGHT}
	Font weight.

Detailed Description

Manages a font and properties of a font.

A Font consists of a type face, a size, and a weight. The font face must be installed on the system in order to use it. Usually, if the specified font face cannot be found on the system, a similar font face will be selected.

Class Documentation

◆ egt::v1::Font::FontExtents

struct egt::v1::Font::FontExtents

Font extent.

Class Members
Extent	ascent
Extent	descent
Extent	height
Extent	max_x_advance
Extent	max_y_advance

◆ egt::v1::Font::TextExtents

struct egt::v1::Font::TextExtents

Text extent.

Class Members
Extent	height
Extent	width
Extent	x_advance
Extent	x_bearing
Extent	y_advance
Extent	y_bearing

Member Typedef Documentation

◆ Extent

using Extent = float

◆ Size

using Size = float

Scalar used for font size.

Member Enumeration Documentation

◆ Slant

enum class Slant

strong

Font slants.

Enumerator
normal
italic
oblique

◆ Weight

enum class Weight

strong

Font weights.

Enumerator
normal
bold

Constructor & Destructor Documentation

◆ Font() [1/8]

Font ( )

◆ Font() [2/8]

Font ( const std::string & face )

explicit

Create a font based on the supplied parameters.

Parameters

[in] face The face name of the font.

◆ Font() [3/8]

Font	(	const unsigned char *	data,
		size_t	len,
		Font::Size	size
	)

explicit

Create a font from an in-memory font.

Parameters

[in]	data	Raw memory to the font.
[in]	len	Size of bytes of the ram memory.
[in]	size	The size of the font.

◆ Font() [4/8]

Font	(	const std::string &	face,
		Font::Size	size,
		Font::Weight	weight = `Weight::normal`,
		Font::Slant	slant = `Slant::normal`
	)

explicit

Create a font based on the supplied parameters.

Parameters

[in]	face	The face name of the font.
[in]	size	The size of the font.
[in]	weight	The weight of the font.
[in]	slant	The slant of the font.

◆ Font() [5/8]

Font ( Font::Size size )

explicit

Create a font based on the global default font, but with the specified size.

Parameters

[in] size The size of the font.

◆ Font() [6/8]

Font	(	Font::Size	size,
		Font::Weight	weight
	)

explicit

Create a font based on the global default font, but with the specified size and weight.

Parameters

[in]	size	The size of the font.
[in]	weight	The weight of the font.

◆ Font() [7/8]

Font ( Font::Weight weight )

explicit

Create a font based on the global default font, but with the specified weight.

Parameters

[in] weight The weight of the font.

◆ Font() [8/8]

Font ( Font::Slant slant )

explicit

Create a font based on the global default font, but with the specified slant.

Parameters

[in] slant The slant of the font.

Member Function Documentation

◆ deserialize()

void deserialize	(	const std::string &	name,
		const std::string &	value,
		const Serializer::Attributes &	attrs
	)

Deserialize.

◆ direct_allocate()

void direct_allocate ( )

protected

◆ extents() [1/2]

EGT_NODISCARD Font::FontExtents extents ( ) const

Get the font extents based on a default context.

Internally, calls 'Painter::extents()' on a default Painter instance, which has no transformation like rotation or symmetry.

If you want to transform the font, then you should call 'Painter::extents()' instead, on the relevant Painter instance.

◆ extents() [2/2]

EGT_NODISCARD Font::TextExtents extents ( const std::string & text ) const

Get the text extents based on a default context.

Internally, calls 'Painter::extents(const std::string&)' on a default Painter instance, which has no transformation like rotation or symmetry.

If you want to transform the font, then you should call 'Painter::extents(const std::string&)' instead, on the relevant Painter instance.

Parameters

[in] text The UTF8 encoded text.

◆ face() [1/2]

EGT_NODISCARD const std::string & face ( ) const

inline

Get the face name the font.

◆ face() [2/2]

void face ( const std::string & face )

inline

Set the face of the font.

◆ on_screen_resized()

void on_screen_resized ( )

Recompute the font size from the screen size but only if it has not been defined by the user.

Note: Called from ComposerScreen::resize() for the theme and global fonts or from Widget::on_screen_resized() for local fonts.

◆ reset_font_cache()

static void reset_font_cache ( )

static

Clears any internal font cache.

This will cause any new requests for fonts to be re-generated.

◆ scaled_font()

EGT_NODISCARD const detail::InternalFont & scaled_font ( ) const

Generates a FontConfig scaled font instance.

Internally, this may use a font cache to limit regeneration of the same font more than once.

◆ serialize()

void serialize	(	const std::string &	name,
		Serializer &	serializer
	)		const

Serialize to the specified serializer.

◆ shutdown_fonts()

static void shutdown_fonts ( )

static

Basically, this will clear the font cache and shutdown FontConfig which will release all memory allocated by FontConfig.

Typically, you should not need to call this. However, this is useful for debugging memory leaks and avoiding false positives in FontConfig. Once you call this function, requesting any Font to be created is likely to not work out well.

◆ size() [1/2]

EGT_NODISCARD Font::Size size ( ) const

inline

Get the size of the font.

◆ size() [2/2]

void size ( const Font::Size & s )

inline

Set the size of the font.

◆ slant() [1/2]

EGT_NODISCARD Font::Slant slant ( ) const

inline

Get the slant of the font.

◆ slant() [2/2]

void slant ( Font::Slant s )

inline

Set the slant of the font.

◆ text_size()

EGT_NODISCARD egt::Size text_size ( const std::string & text ) const

Get the size of a rectangle containing the text, based on a default context.

Internally, calls 'Painter::text_size()' on a default Painter instance, which has no transformation like rotation or symmetry.

If you want to transform the font, then you should call 'Painter::text_size()' instead, on the relevant Painter instance.

Parameters

[in] text The UTF8 encoded text.

Returns: the minimum size of a rectangle containing the text.

◆ weight() [1/2]

EGT_NODISCARD Font::Weight weight ( ) const

inline

Get the weight of the font.

◆ weight() [2/2]

void weight ( Font::Weight w )

inline

Set the weight of the font.

Member Data Documentation

◆ DEFAULT_FACE

constexpr const char* DEFAULT_FACE = "Free Sans"

staticconstexpr

Default font face.

◆ DEFAULT_SIZE

constexpr Font::Size DEFAULT_SIZE = 18.f

staticconstexpr

Default font size.

◆ DEFAULT_SLANT

constexpr Font::Slant DEFAULT_SLANT = Font::Slant::normal

staticconstexpr

Default font slant.

◆ DEFAULT_WEIGHT

constexpr Font::Weight DEFAULT_WEIGHT = Font::Weight::normal

staticconstexpr

Default font weight.

◆ m_data

const unsigned char* m_data {nullptr}

protected

◆ m_face

std::string m_face {DEFAULT_FACE}

protected

Font face name.

◆ m_len

size_t m_len {0}

protected

◆ m_scaled_font

std::shared_ptr<detail::InternalFont> m_scaled_font

mutableprotected

Only used when an in-memory font is created.

◆ m_size

Font::Size m_size

protected

Font size.

◆ m_slant

Font::Slant m_slant {DEFAULT_SLANT}

protected

Font slant.

◆ m_use_default_size

bool m_use_default_size {true}

protected

Use default size.

◆ m_weight

Font::Weight m_weight {DEFAULT_WEIGHT}

protected

Font weight.

Classes

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

Class Documentation

◆ egt::v1::Font::FontExtents

◆ egt::v1::Font::TextExtents

Member Typedef Documentation

◆ Extent

◆ Size

Member Enumeration Documentation

◆ Slant

◆ Weight

Constructor & Destructor Documentation

◆ Font() [1/8]

◆ Font() [2/8]

◆ Font() [3/8]

◆ Font() [4/8]

◆ Font() [5/8]

◆ Font() [6/8]

◆ Font() [7/8]

◆ Font() [8/8]

Member Function Documentation

◆ deserialize()

◆ direct_allocate()

◆ extents() [1/2]

◆ extents() [2/2]

◆ face() [1/2]

◆ face() [2/2]

◆ on_screen_resized()

◆ reset_font_cache()

◆ scaled_font()

◆ serialize()

◆ shutdown_fonts()

◆ size() [1/2]

◆ size() [2/2]

◆ slant() [1/2]

◆ slant() [2/2]

◆ text_size()

◆ weight() [1/2]

◆ weight() [2/2]

Member Data Documentation

◆ DEFAULT_FACE

◆ DEFAULT_SIZE

◆ DEFAULT_SLANT

◆ DEFAULT_WEIGHT

◆ m_data

◆ m_face

◆ m_len

◆ m_scaled_font

◆ m_size

◆ m_slant

◆ m_use_default_size

◆ m_weight