pangomm: Pango::GlyphString Class Reference

A Pango::GlyphString is used to store strings of glyphs with geometry and visual attribute information. More...

#include <pangomm/glyphstring.h>

Public Member Functions
	GlyphString ()

	GlyphString (PangoGlyphString* gobject, bool make_a_copy=true)

	GlyphString (const GlyphString& other)

GlyphString&	operator= (const GlyphString& other)

	GlyphString (GlyphString&& other) noexcept

GlyphString&	operator= (GlyphString&& other) noexcept

	~GlyphString () noexcept

void	swap (GlyphString& other) noexcept

PangoGlyphString*	gobj ()
	Provides access to the underlying C instance. More...

const PangoGlyphString*	gobj () const
	Provides access to the underlying C instance. More...

PangoGlyphString*	gobj_copy () const
	Provides access to the underlying C instance. The caller is responsible for freeing it. Use when directly setting fields in structs. More...

	GlyphString (const Glib::ustring& text, const Analysis& analysis)
	Constructs a string of glyphs from a string of characters. More...

	GlyphString (const Glib::ustring& item_text, const Glib::ustring& paragraph_text, const Analysis& analysis, ShapeFlags flags=ShapeFlags::NONE)
	Constructs a string of glyphs from a string of characters. More...

void	set_size (int new_len)
	Resize a glyph string to the given length. More...

void	get_extents (const Glib::RefPtr< const Font >& font, Rectangle& ink_rect, Rectangle& logical_rect) const
	Compute the logical and ink extents of a glyph string. More...

void	get_extents (int start, int end, const Glib::RefPtr< const Font >& font, Rectangle& ink_rect, Rectangle& logical_rect) const
	Computes the extents of a sub-portion of a glyph string. More...

int	get_width () const
	Computes the logical width of the glyph string as can also be computed using extents(). More...

Rectangle	get_ink_extents (const Glib::RefPtr< const Font >& font) const
	Computes the extents of the glyph string as drawn. More...

Rectangle	get_ink_extents (int start, int end, const Glib::RefPtr< const Font >& font) const
	Computes the extents of a sub-portion of the glyph string as drawn. More...

Rectangle	get_logical_extents (const Glib::RefPtr< const Font >& font) const
	Computes the logical extents of a sub-portion of the glyph string. More...

Rectangle	get_logical_extents (int start, int end, const Glib::RefPtr< const Font >& font) const
	Computes the logical extents of a sub-portion of the glyph string. More...

std::vector< int >	get_logical_widths (const Glib::ustring& text, int embedding_level) const
	Determine the screen width corresponding to each character. More...

int	index_to_x (const Glib::ustring& text, const Analysis& analysis, int index, bool trailing) const
	Converts from character position to x position. More...

void	x_to_index (const Glib::ustring& text, const Analysis& analysis, int x_pos, int& index, bool& trailing) const
	Convert from x offset to character position. More...

std::vector< GlyphInfo >	get_glyphs () const
	Gharacter positions are computed by dividing up each cluster into equal portions. More...

Static Public Member Functions
static GType	get_type ()
	Get the GType for this class, for use with the underlying GObject type system. More...

Protected Attributes
PangoGlyphString*	gobject_

Related Functions
(Note that these are not member functions.)
void	swap (GlyphString& lhs, GlyphString& rhs) noexcept

Pango::GlyphString	wrap (PangoGlyphString* object, bool take_copy=false)
	A Glib::wrap() method for this object. More...

Detailed Description

A Pango::GlyphString is used to store strings of glyphs with geometry and visual attribute information.

It can be measured or drawn to the screen.

Constructor & Destructor Documentation

Pango::GlyphString::GlyphString ( )

Pango::GlyphString::GlyphString	(	PangoGlyphString *	gobject,
		bool	make_a_copy = `true`
	)

explicit

Pango::GlyphString::GlyphString ( const GlyphString& other )

Pango::GlyphString::GlyphString ( GlyphString&& other )

noexcept

Pango::GlyphString::~GlyphString ( )

noexcept

Pango::GlyphString::GlyphString	(	const Glib::ustring &	text,
		const Analysis&	analysis
	)

Constructs a string of glyphs from a string of characters.

Given a segment of text and the corresponding Pango::Analysis structure returned from Pango::Context::itemize(), convert the characters into glyphs. You may also pass in only a substring of the item.

It is recommended that you use the constructor with item_text and paragraph_text parameters instead, since that API allows for shaping interaction happening across text item boundaries.

Parameters

text	The text to process. You must pass the same string into those member functions expecting a const Glib::ustring&.
analysis	The analysis information returned from Pango::Context::itemize().

Pango::GlyphString::GlyphString	(	const Glib::ustring &	item_text,
		const Glib::ustring &	paragraph_text,
		const Analysis&	analysis,
		ShapeFlags	flags = `ShapeFlags::NONE`
	)

Constructs a string of glyphs from a string of characters.

Given a segment of text and the corresponding Pango::Analysis structure returned from Pango::Context::itemize(), convert the characters into glyphs. You may also pass in only a substring of the item.

This is similar to the constructor with only one text parameter, except it also takes flags and the full paragraph text as input, which will then be used to perform certain cross-item shaping interactions. If you have access to the broader text of which item_text is a part, provide the broader text as paragraph_text.

Since pangomm 2.44:

Parameters

item_text	Valid UTF-8 text to shape.
paragraph_text	Text of the paragraph (see details).
analysis	The analysis information returned from Pango::Context::itemize().
flags	Flags influencing the shaping process.

Member Function Documentation

void Pango::GlyphString::get_extents	(	const Glib::RefPtr< const Font >&	font,
		Rectangle&	ink_rect,
		Rectangle&	logical_rect
	)		const

Compute the logical and ink extents of a glyph string.

See the documentation for Pango::Font::get_glyph_extents() for details about the interpretation of the rectangles.

Parameters

font	A Pango::Font.
ink_rect	Rectangle used to store the extents of the glyph string as drawn.
logical_rect	Rectangle used to store the logical extents of the glyph string.

void Pango::GlyphString::get_extents	(	int	start,
		int	end,
		const Glib::RefPtr< const Font >&	font,
		Rectangle&	ink_rect,
		Rectangle&	logical_rect
	)		const

Computes the extents of a sub-portion of a glyph string.

The extents are relative to the start of the glyph string range (the origin of their coordinate system is at the start of the range, not at the start of the entire glyph string).

Parameters

start	Start index.
end	End index (the range is the set of bytes with indices such that start <= index < end).
font	A Pango::Font.
ink_rect	Rectangle used to store the extents of the glyph string range as drawn.
logical_rect	Rectangle used to store the logical extents of the glyph string range.

std::vector<GlyphInfo> Pango::GlyphString::get_glyphs ( ) const

Gharacter positions are computed by dividing up each cluster into equal portions.

Returns: An array of Pango::GlyphInfo objects.

Rectangle Pango::GlyphString::get_ink_extents ( const Glib::RefPtr< const Font >& font ) const

Computes the extents of the glyph string as drawn.

Parameters

font	A Pango::Font.

Returns: The extents of the glyph string as drawn.

Rectangle Pango::GlyphString::get_ink_extents	(	int	start,
		int	end,
		const Glib::RefPtr< const Font >&	font
	)		const

Computes the extents of a sub-portion of the glyph string as drawn.

Parameters

start	The start index.
end	The end index.
font	A Panog::Font

Returns: The extents of the sub-portion of the glyph string as drawn.

Rectangle Pango::GlyphString::get_logical_extents ( const Glib::RefPtr< const Font >& font ) const

Computes the logical extents of a sub-portion of the glyph string.

Parameters

font	A Pango::Font.

Returns: The logical extents of the glyph string.

Rectangle Pango::GlyphString::get_logical_extents	(	int	start,
		int	end,
		const Glib::RefPtr< const Font >&	font
	)		const

Computes the logical extents of a sub-portion of the glyph string.

Parameters

start	The start index.
end	The end index.
font	A Pango::Font.

Returns: The logical extents of the sub-portion of the glyph string.

std::vector<int> Pango::GlyphString::get_logical_widths	(	const Glib::ustring &	text,
		int	embedding_level
	)		const

Determine the screen width corresponding to each character.

When multiple characters compose a single cluster, the width of the entire cluster is divided equally among the characters.

Parameters

text	The text corresponding to the glyphs.
embedding_level	The embedding level of the string.

Returns: An array of integers representing the resulting character widths.

static GType Pango::GlyphString::get_type ( )

static

Get the GType for this class, for use with the underlying GObject type system.

int Pango::GlyphString::get_width ( ) const

Computes the logical width of the glyph string as can also be computed using extents().

However, since this only computes the width, it's much faster. This is in fact only a convenience function that computes the sum of geometry.width for each glyph in the glyphs.

Since pangomm 1.14:

Returns: The logical width of the glyph string.

PangoGlyphString* Pango::GlyphString::gobj ( )

inline

Provides access to the underlying C instance.

const PangoGlyphString* Pango::GlyphString::gobj ( ) const

inline

Provides access to the underlying C instance.

PangoGlyphString* Pango::GlyphString::gobj_copy ( ) const

Provides access to the underlying C instance. The caller is responsible for freeing it. Use when directly setting fields in structs.

int Pango::GlyphString::index_to_x	(	const Glib::ustring &	text,
		const Analysis&	analysis,
		int	index,
		bool	trailing
	)		const

Converts from character position to x position.

(X position is measured from the left edge of the run). Character positions are computed by dividing up each cluster into equal portions.

Parameters

text	The text corresponding to the glyphs.
analysis	The analysis information return from Pango::Context::itemize().
index	The byte index within text.
trailing	Whether we should compute the result for the beginning or end of the character.

Returns: The x position.

GlyphString& Pango::GlyphString::operator= ( const GlyphString& other )

GlyphString& Pango::GlyphString::operator= ( GlyphString&& other )

noexcept

void Pango::GlyphString::set_size ( int new_len )

Resize a glyph string to the given length.

Parameters

new_len The new length of the string.

void Pango::GlyphString::swap ( GlyphString& other )

noexcept

void Pango::GlyphString::x_to_index	(	const Glib::ustring &	text,
		const Analysis&	analysis,
		int	x_pos,
		int &	index,
		bool &	trailing
	)		const

Convert from x offset to character position.

Character positions are computed by dividing up each cluster into equal portions. In scripts where positioning within a cluster is not allowed (such as Thai), the returned value may not be a valid cursor position; the caller must combine the result with the logical attributes for the text to compute the valid cursor position.

Parameters

text	The text corresponding to the glyphs.
analysis	The analysis information return from Pango::Context::itemize().
x_pos	The x offset (in thousands of a device unit).
index	The location to store calculated byte index within.
trailing	The location to store a boolean indicating whether the user clicked on the leading or trailing edge of the character.

Friends And Related Function Documentation

void swap	(	GlyphString&	lhs,
		GlyphString&	rhs
	)

Parameters

lhs	The left-hand side
rhs	The right-hand side

Pango::GlyphString wrap	(	PangoGlyphString *	object,
		bool	take_copy = `false`
	)

A Glib::wrap() method for this object.

Parameters

object	The C instance.
take_copy	False if the result should take ownership of the C instance. True if it should take a new copy or ref.

Returns: A C++ instance that wraps this C instance.

Member Data Documentation

PangoGlyphString* Pango::GlyphString::gobject_

protected

pangomm: Pango::GlyphString Class Reference

Public Member Functions

Static Public Member Functions

Protected Attributes

Related Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation