Pango – 1.0
Description: Reference for Pango-1.0

### Namespace

# Pango – 1.0

Internationalized text layout and rendering

Version | 1.48.5
Authors | Owen Taylor, Behdad Esfahbod
License | GPL-2.1-or-later
Website | https://www.pango.org
Source | https://gitlab.gnome.org/GNOME/pango/

#### Build

C headers | `pango/pango.h`
pkg-config files | `pango`

#### Dependencies

GObject | The base type system library
| Browse documentation
HarfBuzz | A text shaping library
| Browse documentation
PangoCairo | Cairo support for Pango
| Browse documentation
PangoFc | Fontconfig support for Pango
| Browse documentation
PangoFT2 | Freetype support for Pango
| Browse documentation
PangoOT | OpenType support for Pango
| Browse documentation
PangoXft | Xft support for Pango
| Browse documentation

#### Additional documentation

- The Rendering Pipeline
- Text Attributes and Markup
- Fonts and Glyphs
- Bidirectional and Vertical Text
- Classes Hierarchy

#### Classes

Context | A `PangoContext` stores global information used to control the itemization process.
Coverage | A `PangoCoverage` structure is a map from Unicode characters to `PangoCoverageLevel` values.
Font | A `PangoFont` is used to represent a font in a rendering-system-independent manner.
FontFace | A `PangoFontFace` is used to represent a group of fonts with the same family, slant, weight, and width, but varying sizes.
FontFamily | A `PangoFontFamily` is used to represent a family of related font faces.
FontMap | A `PangoFontMap` represents the set of fonts available for a particular rendering system.
Fontset | A `PangoFontset` represents a set of `PangoFont` to use when rendering text.
FontsetSimple | `PangoFontsetSimple` is a implementation of the abstract `PangoFontset` base class as an array of fonts.
Layout | A `PangoLayout` structure represents an entire paragraph of text.
Renderer | `PangoRenderer` is a base class for objects that can render text provided as `PangoGlyphString` or `PangoLayout`.

#### Structs

Analysis | The `PangoAnalysis` structure stores information about the properties of a segment of text.
AttrClass | The `PangoAttrClass` structure stores the type and operations for a particular type of attribute.
AttrColor | The `PangoAttrColor` structure is used to represent attributes that are colors.
AttrFloat | The `PangoAttrFloat` structure is used to represent attributes with a float or double value.
AttrFontDesc | The `PangoAttrFontDesc` structure is used to store an attribute that sets all aspects of the font description at once.
AttrFontFeatures | The `PangoAttrFontFeatures` structure is used to represent OpenType font features as an attribute.
Attribute | The `PangoAttribute` structure represents the common portions of all attributes.
AttrInt | The `PangoAttrInt` structure is used to represent attributes with an integer or enumeration value.
AttrIterator | A `PangoAttrIterator` is used to iterate through a `PangoAttrList`.
AttrLanguage | The `PangoAttrLanguage` structure is used to represent attributes that are languages.
AttrList | A `PangoAttrList` represents a list of attributes that apply to a section of text.
AttrShape | The `PangoAttrShape` structure is used to represent attributes which impose shape restrictions.
AttrSize | The `PangoAttrSize` structure is used to represent attributes which set font size.
AttrString | The `PangoAttrString` structure is used to represent attributes with a string value.
Color | The `PangoColor` structure is used to represent a color in an uncalibrated RGB color-space.
FontDescription | A `PangoFontDescription` describes a font in an implementation-independent manner.
FontMetrics | A `PangoFontMetrics` structure holds the overall metric information for a font.
GlyphGeometry | The `PangoGlyphGeometry` structure contains width and positioning information for a single glyph.
GlyphInfo | A `PangoGlyphInfo` structure represents a single glyph with positioning information and visual attributes.
GlyphItem | A `PangoGlyphItem` is a pair of a `PangoItem` and the glyphs resulting from shaping the items text.
GlyphItemIter | A `PangoGlyphItemIter` is an iterator over the clusters in a `PangoGlyphItem`.
GlyphString | A `PangoGlyphString` is used to store strings of glyphs with geometry and visual attribute information.
GlyphVisAttr | A `PangoGlyphVisAttr` structure communicates information between the shaping and rendering phases.
Item | The `PangoItem` structure stores information about a segment of text.
Language | The `PangoLanguage` structure is used to represent a language.
LayoutIter | A `PangoLayoutIter` can be used to iterate over the visual extents of a `PangoLayout`.
LayoutLine | A `PangoLayoutLine` represents one of the lines resulting from laying out a paragraph via `PangoLayout`.
LogAttr | The `PangoLogAttr` structure stores information about the attributes of a single character.
Matrix | A `PangoMatrix` specifies a transformation between user-space and device coordinates.
Rectangle | The `PangoRectangle` structure represents a rectangle.
ScriptIter | A `PangoScriptIter` is used to iterate through a string and identify ranges in different scripts.
TabArray | A `PangoTabArray` contains an array of tab stops.

#### Aliases

Glyph | A `PangoGlyph` represents a single glyph in the output form of a string.
GlyphUnit | The `PangoGlyphUnit` type is used to store dimensions within Pango.
LayoutRun | A `PangoLayoutRun` represents a single run within a `PangoLayoutLine`.

#### Enumerations

Alignment | `PangoAlignment` describes how to align the lines of a `PangoLayout` within the available space.
AttrType | The `PangoAttrType` distinguishes between different types of attributes.
BidiType | `PangoBidiType` represents the bidirectional character type of a Unicode character as specified by the Unicode bidirectional algorithm.
CoverageLevel | `PangoCoverageLevel` is used to indicate how well a font can represent a particular Unicode character for a particular script.
Direction | `PangoDirection` represents a direction in the Unicode bidirectional algorithm.
EllipsizeMode | `PangoEllipsizeMode` describes what sort of ellipsization should be applied to text.
Gravity | `PangoGravity` represents the orientation of glyphs in a segment of text.
GravityHint | `PangoGravityHint` defines how horizontal scripts should behave in a vertical context.
Overline | The `PangoOverline` enumeration is used to specify whether text should be overlined, and if so, the type of line.
RenderPart | `PangoRenderPart` defines different items to render for such purposes as setting colors.
Script | The `PangoScript` enumeration identifies different writing systems.
Stretch | An enumeration specifying the width of the font relative to other designs within a family.
Style | An enumeration specifying the various slant styles possible for a font.
TabAlign | `PangoTabAlign` specifies where a tab stop appears relative to the text.
Underline | The `PangoUnderline` enumeration is used to specify whether text should be underlined, and if so, the type of underlining.
Variant | An enumeration specifying capitalization variant of the font.
Weight | An enumeration specifying the weight (boldness) of a font.
WrapMode | `PangoWrapMode` describes how to wrap the lines of a `PangoLayout` to the desired width.

#### Bitfields

FontMask | The bits in a `PangoFontMask` correspond to the set fields in a `PangoFontDescription`.
ShapeFlags | Flags influencing the shaping process.
ShowFlags | These flags affect how Pango treats characters that are normally not visible in the output.

#### Callbacks

AttrDataCopyFunc | Type of a function that can duplicate user data for an attribute.
AttrFilterFunc | Type of a function filtering a list of attributes.
FontsetForeachFunc | Callback used by `pango_fontset_foreach()` when enumerating fonts in a fontset.

#### Functions

attr_allow_breaks_new | Create a new allow-breaks attribute.
attr_background_alpha_new | Create a new background alpha attribute.
attr_background_new | Create a new background color attribute.
attr_fallback_new | Create a new font fallback attribute.
attr_family_new | Create a new font family attribute.
attr_foreground_alpha_new | Create a new foreground alpha attribute.
attr_foreground_new | Create a new foreground color attribute.
attr_gravity_hint_new | Create a new gravity hint attribute.
attr_gravity_new | Create a new gravity attribute.
attr_insert_hyphens_new | Create a new insert-hyphens attribute.
attr_letter_spacing_new | Create a new letter-spacing attribute.
attr_overline_color_new | Create a new overline color attribute.
attr_overline_new | Create a new overline-style attribute.
attr_rise_new | Create a new baseline displacement attribute.
attr_scale_new | Create a new font size scale attribute.
attr_show_new | Create a new attribute that influences how invisible characters are rendered.
attr_stretch_new | Create a new font stretch attribute.
attr_strikethrough_color_new | Create a new strikethrough color attribute.
attr_strikethrough_new | Create a new strike-through attribute.
attr_style_new | Create a new font slant style attribute.
attr_underline_color_new | Create a new underline color attribute.
attr_underline_new | Create a new underline-style attribute.
attr_variant_new | Create a new font variant attribute (normal or small caps).
attr_weight_new | Create a new font weight attribute.
break | Determines possible line, word, and character breaks for a string of Unicode text with a single analysis.
default_break | This is the default break algorithm.
extents_to_pixels | Converts extents from Pango units to device units.
find_base_dir | Searches a string the first character that has a strong direction, according to the Unicode bidirectional algorithm.
find_paragraph_boundary | Locates a paragraph boundary in `text`.
get_log_attrs | Computes a `PangoLogAttr` for each character in `text`.
get_mirror_char | Returns the mirrored character of a Unicode character.
is_zero_width | Checks if a character that should not be normally rendered.
itemize | Breaks a piece of text into segments with consistent directional level and font.
itemize_with_base_dir | Like `pango_itemize()`, but with an explicitly specified base direction.
log2vis_get_embedding_levels | Return the bidirectional embedding levels of the input paragraph.
markup_parser_finish | Finishes parsing markup.
markup_parser_new | Incrementally parses marked-up text to create a plain-text string and an attribute list.
parse_enum | Parses an enum type and stores the result in `value`.
parse_markup | Parses marked-up text to create a plain-text string and an attribute list.
parse_stretch | Parses a font stretch.
parse_style | Parses a font style.
parse_variant | Parses a font variant.
parse_weight | Parses a font weight.
quantize_line_geometry | Quantizes the thickness and position of a line to whole device pixels.
read_line | Reads an entire line from a file into a buffer.
reorder_items | Reorder items from logical order to visual order.
scan_int | Scans an integer.
scan_string | Scans a string into a `GString` buffer.
scan_word | Scans a word into a `GString` buffer.
shape | Convert the characters in `text` into glyphs.
shape_full | Convert the characters in `text` into glyphs.
shape_with_flags | Convert the characters in `text` into glyphs.
skip_space | Skips 0 or more characters of white space.
split_file_list | Splits a `G_SEARCHPATH_SEPARATOR`-separated list of files, stripping white space and substituting ~/ with $HOME/.
tailor_break | Apply language-specific tailoring to the breaks in `log_attrs`.
trim_string | Trims leading and trailing whitespace from a string.
unichar_direction | Determines the inherent direction of a character.
units_from_double | Converts a floating-point number to Pango units.
units_to_double | Converts a number in Pango units to floating-point.
version | Returns the encoded version of Pango available at run-time.
version_check | Checks that the Pango library in use is compatible with the given version.
version_string | Returns the version of Pango available at run-time.

#### Function Macros

ASCENT | Extracts the ascent from a `PangoRectangle` representing glyph extents. The ascent is the distance from the baseline to the highest point of the character. This is positive if the glyph ascends above the baseline.
DESCENT | Extracts the descent from a `PangoRectangle` representing glyph extents. The descent is the distance from the baseline to the lowest point of the character. This is positive if the glyph descends below the baseline.
LBEARING | Extracts the left bearing from a `PangoRectangle` representing glyph extents. The left bearing is the distance from the horizontal origin to the farthest left point of the character. This is positive for characters drawn completely to the right of the glyph origin.
PIXELS | Converts a dimension to device units by rounding.
PIXELS_CEIL | Converts a dimension to device units by ceiling.
PIXELS_FLOOR | Converts a dimension to device units by flooring.
RBEARING | Extracts the right bearing from a `PangoRectangle` representing glyph extents. The right bearing is the distance from the horizontal origin to the farthest right point of the character. This is positive except for characters drawn completely to the left of the horizontal origin.
UNITS_ROUND | Rounds a dimension to whole device units, but does not convert it to device units.
VERSION_CHECK | Checks that the version of Pango available at compile-time is not older than the provided version number.
VERSION_ENCODE | This macro encodes the given Pango version into an integer. The numbers returned by `PANGO_VERSION` and `pango_version()` are encoded using this macro. Two encoded version numbers can be compared as integers.

#### Constants

ANALYSIS_FLAG_CENTERED_BASELINE | Whether the segment should be shifted to center around the baseline.
ANALYSIS_FLAG_IS_ELLIPSIS | Whether this run holds ellipsized text.
ANALYSIS_FLAG_NEED_HYPHEN | Whether to add a hyphen at the end of the run during shaping.
ATTR_INDEX_FROM_TEXT_BEGINNING | Value for `start_index` in `PangoAttribute` that indicates the beginning of the text.
ATTR_INDEX_TO_TEXT_END | Value for `end_index` in `PangoAttribute` that indicates the end of the text.
GLYPH_EMPTY | A `PangoGlyph` value that indicates a zero-width empty glpyh.
GLYPH_INVALID_INPUT | A `PangoGlyph` value for invalid input.
GLYPH_UNKNOWN_FLAG | Flag used in `PangoGlyph` to turn a `gunichar` value of a valid Unicode character into an unknown-character glyph for that `gunichar`.
SCALE | The scale between dimensions used for Pango distances and device units.
VERSION_MAJOR | The major component of the version of Pango available at compile-time.
VERSION_MICRO | The micro component of the version of Pango available at compile-time.
VERSION_MINOR | The minor component of the version of Pango available at compile-time.
VERSION_STRING | A string literal containing the version of Pango available at compile-time.