Package org.freedesktop.harfbuzz

package org.freedesktop.harfbuzz

The HarfBuzz text shaping engine

The following native libraries are required and will be loaded: libharfbuzz-gobject.0 libharfbuzz.0

For namespace-global declarations, refer to the HarfBuzz class documentation.

Hb-aat-layout

Functions for querying AAT Layout features in the font face.

HarfBuzz supports all of the AAT tables used to implement shaping. Other AAT tables and their associated features are not supported.

Hb-blob

Blobs wrap a chunk of binary data to handle lifecycle management of data while it is passed between client and HarfBuzz. Blobs are primarily used to create font faces, but also to access font face tables, as well as pass around other binary data.

Hb-buffer

Buffers serve a dual role in HarfBuzz; before shaping, they hold the input characters that are passed to hb_shape(), and after shaping they hold the output glyphs.

The input buffer is a sequence of Unicode codepoints, with associated attributes such as direction and script. The output buffer is a sequence of glyphs, with associated attributes such as position and cluster.

Hb-common

Common data types used across HarfBuzz are defined here.

Hb-deprecated

These API have been deprecated in favor of newer API, or because they were deemed unnecessary.

Hb-draw

Functions for drawing (extracting) glyph shapes.

The hb_draw_funcs_t struct can be used with hb_font_draw_glyph().

Hb-face

A font face is an object that represents a single face from within a font family.

More precisely, a font face represents a single face in a binary font file. Font faces are typically built from a binary blob and a face index. Font faces are used to create fonts.

A font face can be created from a binary blob using hb_face_create(). The face index is used to select a face from a binary blob that contains multiple faces. For example, a binary blob that contains both a regular and a bold face can be used to create two font faces, one for each face index.

Hb-font

Functions for working with font objects.

A font object represents a font face at a specific size and with certain other parameters (pixels-per-em, points-per-em, variation settings) specified. Font objects are created from font face objects, and are used as input to hb_shape(), among other things.

Client programs can optionally pass in their own functions that implement the basic, lower-level queries of font objects. This set of font functions is defined by the virtual methods in hb_font_funcs_t.

HarfBuzz provides a built-in set of lightweight default functions for each method in hb_font_funcs_t.

The default font functions are implemented in terms of the hb_font_funcs_t methods of the parent font object. This allows client programs to override only the methods they need to, and otherwise inherit the parent font's implementation, if any.

Hb-ft

Functions for using HarfBuzz with the FreeType library.

HarfBuzz supports using FreeType to provide face and font data.

<note>Note that FreeType is not thread-safe, therefore these functions are not thread-safe either.</note>

Hb-glib

Functions for using HarfBuzz with the GLib library.

HarfBuzz supports using GLib to provide Unicode data, by attaching GLib functions to the virtual methods in a hb_unicode_funcs_t function structure.

Hb-map

Map objects are integer-to-integer hash-maps. Currently they are not used in the HarfBuzz public API, but are provided for client's use if desired.

Hb-ot-color

Functions for fetching color-font information from OpenType font faces.

HarfBuzz supports COLR/CPAL, sbix, CBDT, and SVG color fonts.

Hb-ot-font

Functions for using OpenType fonts with hb_shape(). Note that fonts returned by hb_font_create() default to using these functions, so most clients would never need to call these functions directly.

Hb-ot-layout

Functions for querying OpenType Layout features in the font face. See the OpenType specification for details.

Hb-ot-math

Functions for fetching mathematics layout data from OpenType fonts.

HarfBuzz itself does not implement a math layout solution. The functions and types provided can be used by client programs to access the font data necessary for typesetting OpenType Math layout.

Hb-ot-meta

Functions for fetching metadata from fonts.

Hb-ot-metrics

Functions for fetching metrics from fonts.

Hb-ot-name

Functions for fetching name strings from OpenType fonts.

Hb-ot-shape

Support functions for OpenType shaping related queries.

Hb-ot-var

Functions for fetching information about OpenType Variable Fonts.

Hb-paint

Functions for painting glyphs.

The main purpose of these functions is to paint (extract) color glyph layers from the COLRv1 table, but the API works for drawing ordinary outlines and images as well.

The hb_paint_funcs_t struct can be used with hb_font_paint_glyph().

Hb-set

Set objects represent a mathematical set of integer values. They are used in non-shaping APIs to query certain sets of characters or glyphs, or other integer values.

Hb-shape

Shaping is the central operation of HarfBuzz. Shaping operates on buffers, which are sequences of Unicode characters that use the same font and have the same text direction, script, and language. After shaping the buffer contains the output glyphs and their positions.

Hb-shape-plan

Shape plans are an internal mechanism. Each plan contains state describing how HarfBuzz will shape a particular text segment, based on the combination of segment properties and the capabilities in the font face in use.

Shape plans are not used for shaping directly, but can be queried to access certain information about how shaping will perform, given a set of specific input parameters (script, language, direction, features, etc.).

Most client programs will not need to deal with shape plans directly.

Hb-style

Functions for fetching style information from fonts.

Hb-unicode

Unicode functions are used to access Unicode character properties. With these functions, client programs can query various properties from the Unicode Character Database for any code point, such as General Category (gc), Script (sc), Canonical Combining Class (ccc), etc.

Client programs can optionally pass in their own Unicode functions that implement the same queries. The set of functions available is defined by the virtual methods in hb_unicode_funcs_t.

HarfBuzz provides built-in default functions for each method in hb_unicode_funcs_t.

Hb-version

These functions and macros allow accessing version of the HarfBuzz library used at compile- as well as run-time, and to direct code conditionally based on those versions, again, at compile- or run-time.

Class	Description
AatLayoutFeatureSelector	The selectors defined for specifying AAT feature settings.
AatLayoutFeatureSelectorInfo	Structure representing a setting for an hb_aat_layout_feature_type_t.
AatLayoutFeatureType	The possible feature types defined for AAT shaping, from Apple Font Feature Registry.
Blob	Data type for blobs.
Bool	Data type for booleans.
Buffer	The main structure holding the input text and its properties before shaping, and output glyphs and their information after shaping.
BufferClusterLevel	Data type for holding HarfBuzz's clustering behavior options.
BufferContentType	The type of hb_buffer_t contents.
BufferDiffFlags	Flags from comparing two hb_buffer_t's.
BufferFlags	Flags for hb_buffer_t.
BufferMessageFunc	Functional interface declaration of the BufferMessageFunc callback.
BufferSerializeFlags	Flags that control what glyph information are serialized in hb_buffer_serialize_glyphs().
BufferSerializeFormat	The buffer serialization and de-serialization format used in hb_buffer_serialize_glyphs() and hb_buffer_deserialize_glyphs().
Codepoint	Data type for holding Unicode codepoints.
Color	Data type for holding color values.
ColorLine	A struct containing color information for a gradient.
ColorLineGetColorStopsFunc	Functional interface declaration of the ColorLineGetColorStopsFunc callback.
ColorLineGetExtendFunc	Functional interface declaration of the ColorLineGetExtendFunc callback.
ColorStop	Information about a color stop on a color line.
DestroyFunc	Functional interface declaration of the DestroyFunc callback.
Direction	The direction of a text segment or buffer.
DrawClosePathFunc	Functional interface declaration of the DrawClosePathFunc callback.
DrawCubicToFunc	Functional interface declaration of the DrawCubicToFunc callback.
DrawFuncs	Glyph draw callbacks.
DrawLineToFunc	Functional interface declaration of the DrawLineToFunc callback.
DrawMoveToFunc	Functional interface declaration of the DrawMoveToFunc callback.
DrawQuadraticToFunc	Functional interface declaration of the DrawQuadraticToFunc callback.
DrawState	Current drawing state.
Face	Data type for holding font faces.
Feature	The hb_feature_t is the structure that holds information about requested feature application.
Font	Data type for holding fonts.
FontDrawGlyphFunc	Functional interface declaration of the FontDrawGlyphFunc callback.
FontExtents	Font-wide extent values, measured in font units.
FontFuncs	Data type containing a set of virtual methods used for working on hb_font_t font objects.
FontGetFontExtentsFunc	Functional interface declaration of the FontGetFontExtentsFunc callback.
FontGetFontHExtentsFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetFontVExtentsFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetGlyphAdvanceFunc	Functional interface declaration of the FontGetGlyphAdvanceFunc callback.
FontGetGlyphAdvancesFunc	Functional interface declaration of the FontGetGlyphAdvancesFunc callback.
FontGetGlyphContourPointFunc	Functional interface declaration of the FontGetGlyphContourPointFunc callback.
FontGetGlyphExtentsFunc	Functional interface declaration of the FontGetGlyphExtentsFunc callback.
FontGetGlyphFromNameFunc	Functional interface declaration of the FontGetGlyphFromNameFunc callback.
FontGetGlyphFunc	Deprecated.
FontGetGlyphHAdvanceFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetGlyphHAdvancesFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetGlyphHKerningFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetGlyphHOriginFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetGlyphKerningFunc	Functional interface declaration of the FontGetGlyphKerningFunc callback.
FontGetGlyphNameFunc	Functional interface declaration of the FontGetGlyphNameFunc callback.
FontGetGlyphOriginFunc	Functional interface declaration of the FontGetGlyphOriginFunc callback.
FontGetGlyphShapeFunc	Deprecated.
FontGetGlyphVAdvanceFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetGlyphVAdvancesFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetGlyphVKerningFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetGlyphVOriginFunc	A virtual method for the hb_font_funcs_t of an hb_font_t object.
FontGetNominalGlyphFunc	Functional interface declaration of the FontGetNominalGlyphFunc callback.
FontGetNominalGlyphsFunc	Functional interface declaration of the FontGetNominalGlyphsFunc callback.
FontGetVariationGlyphFunc	Functional interface declaration of the FontGetVariationGlyphFunc callback.
FontPaintGlyphFunc	Functional interface declaration of the FontPaintGlyphFunc callback.
GlyphExtents	Glyph extent values, measured in font units.
GlyphFlags	Flags for hb_glyph_info_t.
GlyphInfo	The hb_glyph_info_t is the structure that holds information about the glyphs and their relation to input text.
GlyphPosition	The hb_glyph_position_t is the structure that holds the positions of the glyph in both horizontal and vertical directions.
HarfBuzz	Constants and functions that are declared in the global HarfBuzz namespace.
Language	Data type for languages.
Map	Data type for holding integer-to-integer hash maps.
Mask	Data type for bitmasks.
MemoryMode	Data type holding the memory modes available to client programs.
OtColorLayer	Pairs of glyph and color index.
OtColorPaletteFlags	Flags that describe the properties of color palette.
OtLayoutBaselineTag	Baseline tags from Baseline Tags registry.
OtLayoutGlyphClass	The GDEF classes defined for glyphs.
OtMathConstant	The 'MATH' table constants, refer to OpenType documentation For more explanations.
OtMathGlyphPart	Data type to hold information for a "part" component of a math-variant glyph.
OtMathGlyphPartFlags	Flags for math glyph parts.
OtMathGlyphVariant	Data type to hold math-variant information for a glyph.
OtMathKern	The math kerning-table types defined for the four corners of a glyph.
OtMathKernEntry	Data type to hold math kerning (cut-in) information for a glyph.
OtMetaTag	Known metadata tags from https://docs.microsoft.com/en-us/typography/opentype/spec/meta
OtMetricsTag	Metric tags corresponding to [MVAR Value Tags](https://docs.microsoft.com/en-us/typography/opentype/spec/mvarvalue-tags)
OtNameEntry	Structure representing a name ID in a particular language.
OtNameId	An integral type representing an OpenType 'name' table name identifier.
OtNameIdPredefined	An enum type representing the pre-defined name IDs.
OtVarAxis	Deprecated.
OtVarAxisFlags	Flags for hb_ot_var_axis_info_t.
OtVarAxisInfo	Data type for holding variation-axis values.
PaintColorFunc	Functional interface declaration of the PaintColorFunc callback.
PaintColorGlyphFunc	Functional interface declaration of the PaintColorGlyphFunc callback.
PaintCompositeMode	The values of this enumeration describe the compositing modes that can be used when combining temporary redirected drawing with the backdrop.
PaintCustomPaletteColorFunc	Functional interface declaration of the PaintCustomPaletteColorFunc callback.
PaintExtend	The values of this enumeration determine how color values outside the minimum and maximum defined offset on a hb_color_line_t are determined.
PaintFuncs	Glyph paint callbacks.
PaintImageFunc	Functional interface declaration of the PaintImageFunc callback.
PaintLinearGradientFunc	Functional interface declaration of the PaintLinearGradientFunc callback.
PaintPopClipFunc	Functional interface declaration of the PaintPopClipFunc callback.
PaintPopGroupFunc	Functional interface declaration of the PaintPopGroupFunc callback.
PaintPopTransformFunc	Functional interface declaration of the PaintPopTransformFunc callback.
PaintPushClipGlyphFunc	Functional interface declaration of the PaintPushClipGlyphFunc callback.
PaintPushClipRectangleFunc	Functional interface declaration of the PaintPushClipRectangleFunc callback.
PaintPushGroupFunc	Functional interface declaration of the PaintPushGroupFunc callback.
PaintPushTransformFunc	Functional interface declaration of the PaintPushTransformFunc callback.
PaintRadialGradientFunc	Functional interface declaration of the PaintRadialGradientFunc callback.
PaintSweepGradientFunc	Functional interface declaration of the PaintSweepGradientFunc callback.
Position	Data type for holding a single coordinate value.
ReferenceTableFunc	Functional interface declaration of the ReferenceTableFunc callback.
Script	Data type for scripts.
SegmentProperties	The structure that holds various text properties of an hb_buffer_t.
Set	Data type for holding a set of integers.
ShapePlan	Data type for holding a shaping plan.
StyleTag	Defined by OpenType Design-Variation Axis Tag Registry.
Tag	Data type for tag identifiers.
UnicodeCombiningClass	Data type for the Canonical_Combining_Class (ccc) property from the Unicode Character Database.
UnicodeCombiningClassFunc	Functional interface declaration of the UnicodeCombiningClassFunc callback.
UnicodeComposeFunc	Functional interface declaration of the UnicodeComposeFunc callback.
UnicodeDecomposeCompatibilityFunc	Deprecated.
UnicodeDecomposeFunc	Functional interface declaration of the UnicodeDecomposeFunc callback.
UnicodeEastasianWidthFunc	Deprecated.
UnicodeFuncs	Data type containing a set of virtual methods used for accessing various Unicode character properties.
UnicodeGeneralCategory	Data type for the "General_Category" (gc) property from the Unicode Character Database.
UnicodeGeneralCategoryFunc	Functional interface declaration of the UnicodeGeneralCategoryFunc callback.
UnicodeMirroringFunc	Functional interface declaration of the UnicodeMirroringFunc callback.
UnicodeScriptFunc	Functional interface declaration of the UnicodeScriptFunc callback.
UserDataKey	Data structure for holding user-data keys.
Variation	Data type for holding variation data.
VarInt
VarNum