hb-font

hb-font — Font objects

Functions

void hb_font_add_glyph_origin_for_direction ()
hb_font_t * hb_font_create ()
hb_font_t * hb_font_create_sub_font ()
void hb_font_destroy ()
hb_font_funcs_t * hb_font_funcs_create ()
void hb_font_funcs_destroy ()
hb_font_funcs_t * hb_font_funcs_get_empty ()
void * hb_font_funcs_get_user_data ()
hb_bool_t hb_font_funcs_is_immutable ()
void hb_font_funcs_make_immutable ()
hb_font_funcs_t * hb_font_funcs_reference ()
void hb_font_funcs_set_glyph_contour_point_func ()
void hb_font_funcs_set_glyph_extents_func ()
void hb_font_funcs_set_glyph_from_name_func ()
void hb_font_funcs_set_glyph_h_advance_func ()
void hb_font_funcs_set_glyph_h_advances_func ()
void hb_font_funcs_set_glyph_h_kerning_func ()
void hb_font_funcs_set_glyph_h_origin_func ()
void hb_font_funcs_set_glyph_name_func ()
void hb_font_funcs_set_glyph_shape_func ()
void hb_font_funcs_set_glyph_v_advance_func ()
void hb_font_funcs_set_glyph_v_advances_func ()
void hb_font_funcs_set_glyph_v_origin_func ()
void hb_font_funcs_set_nominal_glyph_func ()
void hb_font_funcs_set_nominal_glyphs_func ()
hb_bool_t hb_font_funcs_set_user_data ()
void hb_font_funcs_set_variation_glyph_func ()
hb_font_t * hb_font_get_empty ()
hb_face_t * hb_font_get_face ()
hb_bool_t hb_font_get_glyph ()
void hb_font_get_glyph_advance_for_direction ()
hb_position_t (*hb_font_get_glyph_advance_func_t) ()
void hb_font_get_glyph_advances_for_direction ()
void (*hb_font_get_glyph_advances_func_t) ()
hb_bool_t hb_font_get_glyph_contour_point ()
hb_bool_t hb_font_get_glyph_contour_point_for_origin ()
hb_bool_t (*hb_font_get_glyph_contour_point_func_t) ()
hb_bool_t hb_font_get_glyph_extents ()
hb_bool_t hb_font_get_glyph_extents_for_origin ()
hb_bool_t (*hb_font_get_glyph_extents_func_t) ()
hb_bool_t hb_font_get_glyph_from_name ()
hb_bool_t (*hb_font_get_glyph_from_name_func_t) ()
hb_position_t hb_font_get_glyph_h_advance ()
void hb_font_get_glyph_h_advances ()
hb_position_t hb_font_get_glyph_h_kerning ()
hb_bool_t hb_font_get_glyph_h_origin ()
void hb_font_get_glyph_kerning_for_direction ()
hb_position_t (*hb_font_get_glyph_kerning_func_t) ()
hb_bool_t hb_font_get_glyph_name ()
hb_bool_t (*hb_font_get_glyph_name_func_t) ()
void hb_font_get_glyph_origin_for_direction ()
hb_bool_t (*hb_font_get_glyph_origin_func_t) ()
void hb_font_get_glyph_shape ()
void (*hb_font_get_glyph_shape_func_t) ()
hb_position_t hb_font_get_glyph_v_advance ()
void hb_font_get_glyph_v_advances ()
hb_bool_t hb_font_get_glyph_v_origin ()
hb_bool_t hb_font_get_nominal_glyph ()
hb_bool_t (*hb_font_get_nominal_glyph_func_t) ()
unsigned int hb_font_get_nominal_glyphs ()
hb_font_t * hb_font_get_parent ()
void hb_font_get_ppem ()
float hb_font_get_ptem ()
void hb_font_get_scale ()
float hb_font_get_synthetic_slant ()
void * hb_font_get_user_data ()
hb_bool_t hb_font_get_variation_glyph ()
hb_bool_t (*hb_font_get_variation_glyph_func_t) ()
const float * hb_font_get_var_coords_design ()
const int * hb_font_get_var_coords_normalized ()
hb_bool_t hb_font_glyph_from_string ()
void hb_font_glyph_to_string ()
hb_bool_t hb_font_is_immutable ()
void hb_font_make_immutable ()
unsigned int hb_font_get_serial ()
void hb_font_changed ()
hb_font_t * hb_font_reference ()
void hb_font_set_face ()
void hb_font_set_funcs ()
void hb_font_set_funcs_data ()
void hb_font_set_parent ()
void hb_font_set_ppem ()
void hb_font_set_ptem ()
void hb_font_set_scale ()
void hb_font_set_synthetic_slant ()
hb_bool_t hb_font_set_user_data ()
void hb_font_set_variations ()
void hb_font_set_var_coords_design ()
void hb_font_set_var_coords_normalized ()
void hb_font_set_var_named_instance ()
void hb_font_subtract_glyph_origin_for_direction ()
hb_blob_t * (*hb_reference_table_func_t) ()
void hb_font_funcs_set_font_h_extents_func ()
void hb_font_funcs_set_font_v_extents_func ()
void hb_font_get_extents_for_direction ()
hb_bool_t (*hb_font_get_font_extents_func_t) ()
hb_bool_t hb_font_get_h_extents ()
hb_bool_t hb_font_get_v_extents ()

Types and Values

Includes

#include <hb.h>

Description

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.

Functions

hb_font_add_glyph_origin_for_direction ()

void
hb_font_add_glyph_origin_for_direction
                               (hb_font_t *font,
                                hb_codepoint_t glyph,
                                hb_direction_t direction,
                                hb_position_t *x,
                                hb_position_t *y);

Adds the origin coordinates to an (X,Y) point coordinate, in the specified glyph ID in the specified font.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

direction

The direction of the text segment

 

x

Input = The original X coordinate Output = The X coordinate plus the X-coordinate of the origin.

[inout]

y

Input = The original Y coordinate Output = The Y coordinate plus the Y-coordinate of the origin.

[inout]

Since: 0.9.2


hb_font_create ()

hb_font_t *
hb_font_create (hb_face_t *face);

Constructs a new font object from the specified face.

Note: If face's index value (as passed to hb_face_create() has non-zero top 16-bits, those bits minus one are passed to hb_font_set_var_named_instance(), effectively loading a named-instance of a variable font, instead of the default-instance. This allows specifying which named-instance to load by default when creating the face.

Parameters

face

a face.

 

Returns

The new font object.

[transfer full]

Since: 0.9.2


hb_font_create_sub_font ()

hb_font_t *
hb_font_create_sub_font (hb_font_t *parent);

Constructs a sub-font font object from the specified parent font, replicating the parent's properties.

Parameters

parent

The parent font object

 

Returns

The new sub-font font object.

[transfer full]

Since: 0.9.2


hb_font_destroy ()

void
hb_font_destroy (hb_font_t *font);

Decreases the reference count on the given font object. When the reference count reaches zero, the font is destroyed, freeing all memory.

[skip]

Parameters

font

hb_font_t to work upon

 

Since: 0.9.2


hb_font_funcs_create ()

hb_font_funcs_t *
hb_font_funcs_create (void);

Creates a new hb_font_funcs_t structure of font functions.

Returns

The font-functions structure.

[transfer full]

Since: 0.9.2


hb_font_funcs_destroy ()

void
hb_font_funcs_destroy (hb_font_funcs_t *ffuncs);

Decreases the reference count on a font-functions structure. When the reference count reaches zero, the font-functions structure is destroyed, freeing all memory.

[skip]

Parameters

ffuncs

The font-functions structure

 

Since: 0.9.2


hb_font_funcs_get_empty ()

hb_font_funcs_t *
hb_font_funcs_get_empty (void);

Fetches an empty font-functions structure.

Returns

The font-functions structure.

[transfer full]

Since: 0.9.2


hb_font_funcs_get_user_data ()

void *
hb_font_funcs_get_user_data (const hb_font_funcs_t *ffuncs,
                             hb_user_data_key_t *key);

Fetches the user data associated with the specified key, attached to the specified font-functions structure.

[skip]

Parameters

ffuncs

The font-functions structure

 

key

The user-data key to query

 

Returns

A pointer to the user data.

[transfer none]

Since: 0.9.2


hb_font_funcs_is_immutable ()

hb_bool_t
hb_font_funcs_is_immutable (hb_font_funcs_t *ffuncs);

Tests whether a font-functions structure is immutable.

Parameters

ffuncs

The font-functions structure

 

Returns

true if ffuncs is immutable, false otherwise

Since: 0.9.2


hb_font_funcs_make_immutable ()

void
hb_font_funcs_make_immutable (hb_font_funcs_t *ffuncs);

Makes a font-functions structure immutable.

Parameters

ffuncs

The font-functions structure

 

Since: 0.9.2


hb_font_funcs_reference ()

hb_font_funcs_t *
hb_font_funcs_reference (hb_font_funcs_t *ffuncs);

Increases the reference count on a font-functions structure.

[skip]

Parameters

ffuncs

The font-functions structure

 

Returns

The font-functions structure

Since: 0.9.2


hb_font_funcs_set_glyph_contour_point_func ()

void
hb_font_funcs_set_glyph_contour_point_func
                               (hb_font_funcs_t *ffuncs,
                                hb_font_get_glyph_contour_point_func_t func,
                                void *user_data,
                                hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_contour_point_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_glyph_extents_func ()

void
hb_font_funcs_set_glyph_extents_func (hb_font_funcs_t *ffuncs,
                                      hb_font_get_glyph_extents_func_t func,
                                      void *user_data,
                                      hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_extents_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_glyph_from_name_func ()

void
hb_font_funcs_set_glyph_from_name_func
                               (hb_font_funcs_t *ffuncs,
                                hb_font_get_glyph_from_name_func_t func,
                                void *user_data,
                                hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_from_name_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_glyph_h_advance_func ()

void
hb_font_funcs_set_glyph_h_advance_func
                               (hb_font_funcs_t *ffuncs,
                                hb_font_get_glyph_h_advance_func_t func,
                                void *user_data,
                                hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_h_advance_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_glyph_h_advances_func ()

void
hb_font_funcs_set_glyph_h_advances_func
                               (hb_font_funcs_t *ffuncs,
                                hb_font_get_glyph_h_advances_func_t func,
                                void *user_data,
                                hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_h_advances_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 1.8.6


hb_font_funcs_set_glyph_h_kerning_func ()

void
hb_font_funcs_set_glyph_h_kerning_func
                               (hb_font_funcs_t *ffuncs,
                                hb_font_get_glyph_h_kerning_func_t func,
                                void *user_data,
                                hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_h_kerning_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_glyph_h_origin_func ()

void
hb_font_funcs_set_glyph_h_origin_func (hb_font_funcs_t *ffuncs,
                                       hb_font_get_glyph_h_origin_func_t func,
                                       void *user_data,
                                       hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_h_origin_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_glyph_name_func ()

void
hb_font_funcs_set_glyph_name_func (hb_font_funcs_t *ffuncs,
                                   hb_font_get_glyph_name_func_t func,
                                   void *user_data,
                                   hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_name_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_glyph_shape_func ()

void
hb_font_funcs_set_glyph_shape_func (hb_font_funcs_t *ffuncs,
                                    hb_font_get_glyph_shape_func_t func,
                                    void *user_data,
                                    hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_shape_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 4.0.0


hb_font_funcs_set_glyph_v_advance_func ()

void
hb_font_funcs_set_glyph_v_advance_func
                               (hb_font_funcs_t *ffuncs,
                                hb_font_get_glyph_v_advance_func_t func,
                                void *user_data,
                                hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_v_advance_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_glyph_v_advances_func ()

void
hb_font_funcs_set_glyph_v_advances_func
                               (hb_font_funcs_t *ffuncs,
                                hb_font_get_glyph_v_advances_func_t func,
                                void *user_data,
                                hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_v_advances_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 1.8.6


hb_font_funcs_set_glyph_v_origin_func ()

void
hb_font_funcs_set_glyph_v_origin_func (hb_font_funcs_t *ffuncs,
                                       hb_font_get_glyph_v_origin_func_t func,
                                       void *user_data,
                                       hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_glyph_v_origin_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_funcs_set_nominal_glyph_func ()

void
hb_font_funcs_set_nominal_glyph_func (hb_font_funcs_t *ffuncs,
                                      hb_font_get_nominal_glyph_func_t func,
                                      void *user_data,
                                      hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_nominal_glyph_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 1.2.3


hb_font_funcs_set_nominal_glyphs_func ()

void
hb_font_funcs_set_nominal_glyphs_func (hb_font_funcs_t *ffuncs,
                                       hb_font_get_nominal_glyphs_func_t func,
                                       void *user_data,
                                       hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_nominal_glyphs_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 2.0.0


hb_font_funcs_set_user_data ()

hb_bool_t
hb_font_funcs_set_user_data (hb_font_funcs_t *ffuncs,
                             hb_user_data_key_t *key,
                             void *data,
                             hb_destroy_func_t destroy,
                             hb_bool_t replace);

Attaches a user-data key/data pair to the specified font-functions structure.

[skip]

Parameters

ffuncs

The font-functions structure

 

key

The user-data key to set

 

data

A pointer to the user data set

 

destroy

A callback to call when data is not needed anymore.

[nullable]

replace

Whether to replace an existing data with the same key

 

Returns

true if success, false otherwise

Since: 0.9.2


hb_font_funcs_set_variation_glyph_func ()

void
hb_font_funcs_set_variation_glyph_func
                               (hb_font_funcs_t *ffuncs,
                                hb_font_get_variation_glyph_func_t func,
                                void *user_data,
                                hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_variation_glyph_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 1.2.3


hb_font_get_empty ()

hb_font_t *
hb_font_get_empty (void);

Fetches the empty font object.

Returns

The empty font object.

[transfer full]

Since: 0.9.2


hb_font_get_face ()

hb_face_t *
hb_font_get_face (hb_font_t *font);

Fetches the face associated with the specified font object.

Parameters

font

hb_font_t to work upon

 

Returns

The hb_face_t value.

[transfer none]

Since: 0.9.2


hb_font_get_glyph ()

hb_bool_t
hb_font_get_glyph (hb_font_t *font,
                   hb_codepoint_t unicode,
                   hb_codepoint_t variation_selector,
                   hb_codepoint_t *glyph);

Fetches the glyph ID for a Unicode code point in the specified font, with an optional variation selector.

If variation_selector is 0, calls hb_font_get_nominal_glyph(); otherwise calls hb_font_get_variation_glyph().

Parameters

font

hb_font_t to work upon

 

unicode

The Unicode code point to query

 

variation_selector

A variation-selector code point

 

glyph

The glyph ID retrieved.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_glyph_advance_for_direction ()

void
hb_font_get_glyph_advance_for_direction
                               (hb_font_t *font,
                                hb_codepoint_t glyph,
                                hb_direction_t direction,
                                hb_position_t *x,
                                hb_position_t *y);

Fetches the advance for a glyph ID from the specified font, in a text segment of the specified direction.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

direction

The direction of the text segment

 

x

The horizontal advance retrieved.

[out]

y

The vertical advance retrieved.

[out]

Since: 0.9.2


hb_font_get_glyph_advance_func_t ()

hb_position_t
(*hb_font_get_glyph_advance_func_t) (hb_font_t *font,
                                     void *font_data,
                                     hb_codepoint_t glyph,
                                     void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the advance for a specified glyph. The method must return an hb_position_t.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

glyph

The glyph ID to query

 

user_data

User data pointer passed by the caller

 

Returns

The advance of glyph within font


hb_font_get_glyph_advances_for_direction ()

void
hb_font_get_glyph_advances_for_direction
                               (hb_font_t *font,
                                hb_direction_t direction,
                                unsigned int count,
                                const hb_codepoint_t *first_glyph,
                                unsigned  glyph_stride,
                                hb_position_t *first_advance,
                                unsigned  advance_stride);

Fetches the advances for a sequence of glyph IDs in the specified font, in a text segment of the specified direction.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

direction

The direction of the text segment

 

count

The number of glyph IDs in the sequence queried

 

first_glyph

The first glyph ID to query

 

glyph_stride

The stride between successive glyph IDs

 

first_advance

The first advance retrieved.

[out]

advance_stride

The stride between successive advances.

[out]

Since: 1.8.6


hb_font_get_glyph_advances_func_t ()

void
(*hb_font_get_glyph_advances_func_t) (hb_font_t *font,
                                      void *font_data,
                                      unsigned int count,
                                      const hb_codepoint_t *first_glyph,
                                      unsigned  glyph_stride,
                                      hb_position_t *first_advance,
                                      unsigned  advance_stride,
                                      void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the advances for a sequence of glyphs.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

count

The number of glyph IDs in the sequence queried

 

first_glyph

The first glyph ID to query

 

glyph_stride

The stride between successive glyph IDs

 

first_advance

The first advance retrieved.

[out]

advance_stride

The stride between successive advances

 

user_data

User data pointer passed by the caller

 

hb_font_get_glyph_contour_point ()

hb_bool_t
hb_font_get_glyph_contour_point (hb_font_t *font,
                                 hb_codepoint_t glyph,
                                 unsigned int point_index,
                                 hb_position_t *x,
                                 hb_position_t *y);

Fetches the (x,y) coordinates of a specified contour-point index in the specified glyph, within the specified font.

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

point_index

The contour-point index to query

 

x

The X value retrieved for the contour point.

[out]

y

The Y value retrieved for the contour point.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_glyph_contour_point_for_origin ()

hb_bool_t
hb_font_get_glyph_contour_point_for_origin
                               (hb_font_t *font,
                                hb_codepoint_t glyph,
                                unsigned int point_index,
                                hb_direction_t direction,
                                hb_position_t *x,
                                hb_position_t *y);

Fetches the (X,Y) coordinates of a specified contour-point index in the specified glyph ID in the specified font, with respect to the origin in a text segment in the specified direction.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

point_index

The contour-point index to query

 

direction

The direction of the text segment

 

x

The X value retrieved for the contour point.

[out]

y

The Y value retrieved for the contour point.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_glyph_contour_point_func_t ()

hb_bool_t
(*hb_font_get_glyph_contour_point_func_t)
                               (hb_font_t *font,
                                void *font_data,
                                hb_codepoint_t glyph,
                                unsigned int point_index,
                                hb_position_t *x,
                                hb_position_t *y,
                                void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the (X,Y) coordinates (in font units) for a specified contour point in a glyph. Each coordinate must be returned as an hb_position_t output parameter.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

glyph

The glyph ID to query

 

point_index

The contour-point index to query

 

x

The X value retrieved for the contour point.

[out]

y

The Y value retrieved for the contour point.

[out]

user_data

User data pointer passed by the caller

 

Returns

true if data found, false otherwise


hb_font_get_glyph_extents ()

hb_bool_t
hb_font_get_glyph_extents (hb_font_t *font,
                           hb_codepoint_t glyph,
                           hb_glyph_extents_t *extents);

Fetches the hb_glyph_extents_t data for a glyph ID in the specified font.

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

extents

The hb_glyph_extents_t retrieved.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_glyph_extents_for_origin ()

hb_bool_t
hb_font_get_glyph_extents_for_origin (hb_font_t *font,
                                      hb_codepoint_t glyph,
                                      hb_direction_t direction,
                                      hb_glyph_extents_t *extents);

Fetches the hb_glyph_extents_t data for a glyph ID in the specified font, with respect to the origin in a text segment in the specified direction.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

direction

The direction of the text segment

 

extents

The hb_glyph_extents_t retrieved.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_glyph_extents_func_t ()

hb_bool_t
(*hb_font_get_glyph_extents_func_t) (hb_font_t *font,
                                     void *font_data,
                                     hb_codepoint_t glyph,
                                     hb_glyph_extents_t *extents,
                                     void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the extents for a specified glyph. Extents must be returned in an hb_glyph_extents output parameter.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

glyph

The glyph ID to query

 

extents

The hb_glyph_extents_t retrieved.

[out]

user_data

User data pointer passed by the caller

 

Returns

true if data found, false otherwise


hb_font_get_glyph_from_name ()

hb_bool_t
hb_font_get_glyph_from_name (hb_font_t *font,
                             const char *name,
                             int len,
                             hb_codepoint_t *glyph);

Fetches the glyph ID that corresponds to a name string in the specified font .

Note: len == -1 means the name string is null-terminated.

Parameters

font

hb_font_t to work upon

 

name

The name string to query.

[array length=len]

len

The length of the name queried

 

glyph

The glyph ID retrieved.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_glyph_from_name_func_t ()

hb_bool_t
(*hb_font_get_glyph_from_name_func_t) (hb_font_t *font,
                                       void *font_data,
                                       const char *name,
                                       int len);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the glyph ID that corresponds to a glyph-name string.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

name

The name string to query.

[array length=len]

len

The length of the name queried

 

glyph

The glyph ID retrieved.

[out]

user_data

User data pointer passed by the caller

 

Returns

true if data found, false otherwise


hb_font_get_glyph_h_advance ()

hb_position_t
hb_font_get_glyph_h_advance (hb_font_t *font,
                             hb_codepoint_t glyph);

Fetches the advance for a glyph ID in the specified font, for horizontal text segments.

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

Returns

The advance of glyph within font

Since: 0.9.2


hb_font_get_glyph_h_advances ()

void
hb_font_get_glyph_h_advances (hb_font_t *font,
                              unsigned int count,
                              const hb_codepoint_t *first_glyph,
                              unsigned  glyph_stride,
                              hb_position_t *first_advance,
                              unsigned  advance_stride);

Fetches the advances for a sequence of glyph IDs in the specified font, for horizontal text segments.

Parameters

font

hb_font_t to work upon

 

count

The number of glyph IDs in the sequence queried

 

first_glyph

The first glyph ID to query

 

glyph_stride

The stride between successive glyph IDs

 

first_advance

The first advance retrieved.

[out]

advance_stride

The stride between successive advances

 

Since: 1.8.6


hb_font_get_glyph_h_kerning ()

hb_position_t
hb_font_get_glyph_h_kerning (hb_font_t *font,
                             hb_codepoint_t left_glyph,
                             hb_codepoint_t right_glyph);

Fetches the kerning-adjustment value for a glyph-pair in the specified font, for horizontal text segments.

It handles legacy kerning only (as returned by the corresponding hb_font_funcs_t function).

Parameters

font

hb_font_t to work upon

 

left_glyph

The glyph ID of the left glyph in the glyph pair

 

right_glyph

The glyph ID of the right glyph in the glyph pair

 

Returns

The kerning adjustment value

Since: 0.9.2


hb_font_get_glyph_h_origin ()

hb_bool_t
hb_font_get_glyph_h_origin (hb_font_t *font,
                            hb_codepoint_t glyph,
                            hb_position_t *x,
                            hb_position_t *y);

Fetches the (X,Y) coordinates of the origin for a glyph ID in the specified font, for horizontal text segments.

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

x

The X coordinate of the origin.

[out]

y

The Y coordinate of the origin.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_glyph_kerning_for_direction ()

void
hb_font_get_glyph_kerning_for_direction
                               (hb_font_t *font,
                                hb_codepoint_t first_glyph,
                                hb_codepoint_t second_glyph,
                                hb_direction_t direction,
                                hb_position_t *x,
                                hb_position_t *y);

Fetches the kerning-adjustment value for a glyph-pair in the specified font.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

first_glyph

The glyph ID of the first glyph in the glyph pair to query

 

second_glyph

The glyph ID of the second glyph in the glyph pair to query

 

direction

The direction of the text segment

 

x

The horizontal kerning-adjustment value retrieved.

[out]

y

The vertical kerning-adjustment value retrieved.

[out]

Since: 0.9.2


hb_font_get_glyph_kerning_func_t ()

hb_position_t
(*hb_font_get_glyph_kerning_func_t) (hb_font_t *font,
                                     void *font_data,
                                     hb_codepoint_t first_glyph,
                                     hb_codepoint_t second_glyph,
                                     void *user_data);

This method should retrieve the kerning-adjustment value for a glyph-pair in the specified font, for horizontal text segments.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

first_glyph

The glyph ID of the first glyph in the glyph pair

 

second_glyph

The glyph ID of the second glyph in the glyph pair

 

user_data

User data pointer passed by the caller

 

hb_font_get_glyph_name ()

hb_bool_t
hb_font_get_glyph_name (hb_font_t *font,
                        hb_codepoint_t glyph,
                        char *name,
                        unsigned int size);

Fetches the glyph-name string for a glyph ID in the specified font .

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

name

Name string retrieved for the glyph ID.

[out][array length=size]

size

Length of the glyph-name string retrieved

 

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_glyph_name_func_t ()

hb_bool_t
(*hb_font_get_glyph_name_func_t) (hb_font_t *font,
                                  void *font_data,
                                  hb_codepoint_t glyph,
                                  char *name,
                                  unsigned int size,
                                  void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the glyph name that corresponds to a glyph ID. The name should be returned in a string output parameter.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

glyph

The glyph ID to query

 

name

Name string retrieved for the glyph ID.

[out][array length=size]

size

Length of the glyph-name string retrieved

 

user_data

User data pointer passed by the caller

 

Returns

true if data found, false otherwise


hb_font_get_glyph_origin_for_direction ()

void
hb_font_get_glyph_origin_for_direction
                               (hb_font_t *font,
                                hb_codepoint_t glyph,
                                hb_direction_t direction,
                                hb_position_t *x,
                                hb_position_t *y);

Fetches the (X,Y) coordinates of the origin for a glyph in the specified font.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

direction

The direction of the text segment

 

x

The X coordinate retrieved for the origin.

[out]

y

The Y coordinate retrieved for the origin.

[out]

Since: 0.9.2


hb_font_get_glyph_origin_func_t ()

hb_bool_t
(*hb_font_get_glyph_origin_func_t) (hb_font_t *font,
                                    void *font_data,
                                    hb_codepoint_t glyph,
                                    hb_position_t *x,
                                    hb_position_t *y,
                                    void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the (X,Y) coordinates (in font units) of the origin for a glyph. Each coordinate must be returned in an hb_position_t output parameter.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

glyph

The glyph ID to query

 

x

The X coordinate of the origin.

[out]

y

The Y coordinate of the origin.

[out]

user_data

User data pointer passed by the caller

 

Returns

true if data found, false otherwise


hb_font_get_glyph_shape ()

void
hb_font_get_glyph_shape (hb_font_t *font,
                         hb_codepoint_t glyph,
                         hb_draw_funcs_t *dfuncs,
                         void *draw_data);

Fetches the glyph shape that corresponds to a glyph in the specified font . The shape is returned by way of calls to the callsbacks of the dfuncs objects, with draw_data passed to them.

Parameters

font

hb_font_t to work upon

 

glyph

: The glyph ID

 

dfuncs

hb_draw_funcs_t to draw to

 

draw_data

User data to pass to draw callbacks

 

Since: 4.0.0


hb_font_get_glyph_shape_func_t ()

void
(*hb_font_get_glyph_shape_func_t) (hb_font_t *font,
                                   void *font_data,
                                   hb_codepoint_t glyph,
                                   hb_draw_funcs_t *draw_funcs,
                                   void *draw_data,
                                   void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

glyph

The glyph ID to query

 

draw_funcs

The draw functions to send the shape data to

 

draw_data

The data accompanying the draw functions

 

user_data

User data pointer passed by the caller

 

Since: 4.0.0


hb_font_get_glyph_v_advance ()

hb_position_t
hb_font_get_glyph_v_advance (hb_font_t *font,
                             hb_codepoint_t glyph);

Fetches the advance for a glyph ID in the specified font, for vertical text segments.

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

Returns

The advance of glyph within font

Since: 0.9.2


hb_font_get_glyph_v_advances ()

void
hb_font_get_glyph_v_advances (hb_font_t *font,
                              unsigned int count,
                              const hb_codepoint_t *first_glyph,
                              unsigned  glyph_stride,
                              hb_position_t *first_advance,
                              unsigned  advance_stride);

Fetches the advances for a sequence of glyph IDs in the specified font, for vertical text segments.

Parameters

font

hb_font_t to work upon

 

count

The number of glyph IDs in the sequence queried

 

first_glyph

The first glyph ID to query

 

glyph_stride

The stride between successive glyph IDs

 

first_advance

The first advance retrieved.

[out]

advance_stride

The stride between successive advances.

[out]

Since: 1.8.6


hb_font_get_glyph_v_origin ()

hb_bool_t
hb_font_get_glyph_v_origin (hb_font_t *font,
                            hb_codepoint_t glyph,
                            hb_position_t *x,
                            hb_position_t *y);

Fetches the (X,Y) coordinates of the origin for a glyph ID in the specified font, for vertical text segments.

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

x

The X coordinate of the origin.

[out]

y

The Y coordinate of the origin.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_get_nominal_glyph ()

hb_bool_t
hb_font_get_nominal_glyph (hb_font_t *font,
                           hb_codepoint_t unicode,
                           hb_codepoint_t *glyph);

Fetches the nominal glyph ID for a Unicode code point in the specified font.

This version of the function should not be used to fetch glyph IDs for code points modified by variation selectors. For variation-selector support, user hb_font_get_variation_glyph() or use hb_font_get_glyph().

Parameters

font

hb_font_t to work upon

 

unicode

The Unicode code point to query

 

glyph

The glyph ID retrieved.

[out]

Returns

true if data found, false otherwise

Since: 1.2.3


hb_font_get_nominal_glyph_func_t ()

hb_bool_t
(*hb_font_get_nominal_glyph_func_t) (hb_font_t *font,
                                     void *font_data,
                                     hb_codepoint_t unicode,
                                     hb_codepoint_t *glyph,
                                     void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the nominal glyph ID for a specified Unicode code point. Glyph IDs must be returned in a hb_codepoint_t output parameter.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

unicode

The Unicode code point to query

 

glyph

The glyph ID retrieved.

[out]

user_data

User data pointer passed by the caller

 

Returns

true if data found, false otherwise


hb_font_get_nominal_glyphs ()

unsigned int
hb_font_get_nominal_glyphs (hb_font_t *font,
                            unsigned int count,
                            const hb_codepoint_t *first_unicode,
                            unsigned int unicode_stride,
                            hb_codepoint_t *first_glyph,
                            unsigned int glyph_stride);

Fetches the nominal glyph IDs for a sequence of Unicode code points. Glyph IDs must be returned in a hb_codepoint_t output parameter.

Parameters

font

hb_font_t to work upon

 

count

number of code points to query

 

first_unicode

The first Unicode code point to query

 

unicode_stride

The stride between successive code points

 

first_glyph

The first glyph ID retrieved.

[out]

glyph_stride

The stride between successive glyph IDs

 

Returns

the number of code points processed

Since: 2.6.3


hb_font_get_parent ()

hb_font_t *
hb_font_get_parent (hb_font_t *font);

Fetches the parent font of font .

Parameters

font

hb_font_t to work upon

 

Returns

The parent font object.

[transfer none]

Since: 0.9.2


hb_font_get_ppem ()

void
hb_font_get_ppem (hb_font_t *font,
                  unsigned int *x_ppem,
                  unsigned int *y_ppem);

Fetches the horizontal and vertical points-per-em (ppem) of a font.

Parameters

font

hb_font_t to work upon

 

x_ppem

Horizontal ppem value.

[out]

y_ppem

Vertical ppem value.

[out]

Since: 0.9.2


hb_font_get_ptem ()

float
hb_font_get_ptem (hb_font_t *font);

Fetches the "point size" of a font. Used in CoreText to implement optical sizing.

Parameters

font

hb_font_t to work upon

 

Returns

Point size. A value of zero means "not set."

Since: 1.6.0


hb_font_get_scale ()

void
hb_font_get_scale (hb_font_t *font,
                   int *x_scale,
                   int *y_scale);

Fetches the horizontal and vertical scale of a font.

Parameters

font

hb_font_t to work upon

 

x_scale

Horizontal scale value.

[out]

y_scale

Vertical scale value.

[out]

Since: 0.9.2


hb_font_get_synthetic_slant ()

float
hb_font_get_synthetic_slant (hb_font_t *font);

Fetches the "synthetic slant" of a font.

Parameters

font

hb_font_t to work upon

 

Returns

Synthetic slant. By default is zero.

Since: 3.3.0


hb_font_get_user_data ()

void *
hb_font_get_user_data (const hb_font_t *font,
                       hb_user_data_key_t *key);

Fetches the user-data object associated with the specified key, attached to the specified font object.

[skip]

Parameters

font

hb_font_t to work upon

 

key

The user-data key to query

 

Returns

Pointer to the user data.

[transfer none]

Since: 0.9.2


hb_font_get_variation_glyph ()

hb_bool_t
hb_font_get_variation_glyph (hb_font_t *font,
                             hb_codepoint_t unicode,
                             hb_codepoint_t variation_selector,
                             hb_codepoint_t *glyph);

Fetches the glyph ID for a Unicode code point when followed by by the specified variation-selector code point, in the specified font.

Parameters

font

hb_font_t to work upon

 

unicode

The Unicode code point to query

 

variation_selector

The variation-selector code point to query

 

glyph

The glyph ID retrieved.

[out]

Returns

true if data found, false otherwise

Since: 1.2.3


hb_font_get_variation_glyph_func_t ()

hb_bool_t
(*hb_font_get_variation_glyph_func_t) (hb_font_t *font,
                                       void *font_data,
                                       hb_codepoint_t unicode,
                                       hb_codepoint_t variation_selector,
                                       hb_codepoint_t *glyph,
                                       void *user_data);

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the glyph ID for a specified Unicode code point followed by a specified Variation Selector code point. Glyph IDs must be returned in a hb_codepoint_t output parameter.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

unicode

The Unicode code point to query

 

variation_selector

The variation-selector code point to query

 

glyph

The glyph ID retrieved.

[out]

user_data

User data pointer passed by the caller

 

Returns

true if data found, false otherwise


hb_font_get_var_coords_design ()

const float *
hb_font_get_var_coords_design (hb_font_t *font,
                               unsigned int *length);

Fetches the list of variation coordinates (in design-space units) currently set on a font.

Note that this returned array may only contain values for some (or none) of the axes; omitted axes effectively have their default values.

Return value is valid as long as variation coordinates of the font are not modified.

Parameters

font

hb_font_t to work upon

 

length

Number of coordinates retrieved.

[out]

Returns

coordinates array

Since: 3.3.0


hb_font_get_var_coords_normalized ()

const int *
hb_font_get_var_coords_normalized (hb_font_t *font,
                                   unsigned int *length);

Fetches the list of normalized variation coordinates currently set on a font.

Note that this returned array may only contain values for some (or none) of the axes; omitted axes effectively have zero values.

Return value is valid as long as variation coordinates of the font are not modified.

Parameters

font

hb_font_t to work upon

 

length

Number of coordinates retrieved.

[out]

Returns

coordinates array

Since: 1.4.2


hb_font_glyph_from_string ()

hb_bool_t
hb_font_glyph_from_string (hb_font_t *font,
                           const char *s,
                           int len,
                           hb_codepoint_t *glyph);

Fetches the glyph ID from font that matches the specified string. Strings of the format gidDDD or uniUUUU are parsed automatically.

Note: len == -1 means the string is null-terminated.

Parameters

font

hb_font_t to work upon

 

s

string to query.

[array length=len][element-type uint8_t]

len

The length of the string s

 

glyph

The glyph ID corresponding to the string requested.

[out]

Returns

true if data found, false otherwise

Since: 0.9.2


hb_font_glyph_to_string ()

void
hb_font_glyph_to_string (hb_font_t *font,
                         hb_codepoint_t glyph,
                         char *s,
                         unsigned int size);

Fetches the name of the specified glyph ID in font and returns it in string s .

If the glyph ID has no name in font , a string of the form gidDDD is generated, with DDD being the glyph ID.

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

s

The string containing the glyph name.

[out][array length=size]

size

Length of string s

 

Since: 0.9.2


hb_font_is_immutable ()

hb_bool_t
hb_font_is_immutable (hb_font_t *font);

Tests whether a font object is immutable.

Parameters

font

hb_font_t to work upon

 

Returns

true if font is immutable, false otherwise

Since: 0.9.2


hb_font_make_immutable ()

void
hb_font_make_immutable (hb_font_t *font);

Makes font immutable.

Parameters

font

hb_font_t to work upon

 

Since: 0.9.2


hb_font_get_serial ()

unsigned int
hb_font_get_serial (hb_font_t *font);

Returns the internal serial number of the font. The serial number is increased every time a setting on the font is changed, using a setter function.

Parameters

font

hb_font_t to work upon

 

Returns

serial number

Since: 4.4.0


hb_font_changed ()

void
hb_font_changed (hb_font_t *font);

Notifies the font that underlying font data has changed. This has the effect of increasing the serial as returned by hb_font_get_serial(), which invalidates internal caches.

Parameters

font

hb_font_t to work upon

 

Since: 4.4.0


hb_font_reference ()

hb_font_t *
hb_font_reference (hb_font_t *font);

Increases the reference count on the given font object.

[skip]

Parameters

font

hb_font_t to work upon

 

Returns

The font object.

[transfer full]

Since: 0.9.2


hb_font_set_face ()

void
hb_font_set_face (hb_font_t *font,
                  hb_face_t *face);

Sets face as the font-face value of font .

Parameters

font

hb_font_t to work upon

 

face

The hb_face_t to assign

 

Since: 1.4.3


hb_font_set_funcs ()

void
hb_font_set_funcs (hb_font_t *font,
                   hb_font_funcs_t *klass,
                   void *font_data,
                   hb_destroy_func_t destroy);

Replaces the font-functions structure attached to a font, updating the font's user-data with font -data and the destroy callback.

Parameters

font

hb_font_t to work upon

 

klass

The font-functions structure.

[closure font_data][destroy destroy][scope notified]

font_data

Data to attach to font

 

destroy

The function to call when font_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_set_funcs_data ()

void
hb_font_set_funcs_data (hb_font_t *font,
                        void *font_data,
                        hb_destroy_func_t destroy);

Replaces the user data attached to a font, updating the font's destroy callback.

Parameters

font

hb_font_t to work upon

 

font_data

Data to attach to font .

[destroy destroy][scope notified]

destroy

The function to call when font_data is not needed anymore.

[nullable]

Since: 0.9.2


hb_font_set_parent ()

void
hb_font_set_parent (hb_font_t *font,
                    hb_font_t *parent);

Sets the parent font of font .

Parameters

font

hb_font_t to work upon

 

parent

The parent font object to assign

 

Since: 1.0.5


hb_font_set_ppem ()

void
hb_font_set_ppem (hb_font_t *font,
                  unsigned int x_ppem,
                  unsigned int y_ppem);

Sets the horizontal and vertical pixels-per-em (ppem) of a font.

Parameters

font

hb_font_t to work upon

 

x_ppem

Horizontal ppem value to assign

 

y_ppem

Vertical ppem value to assign

 

Since: 0.9.2


hb_font_set_ptem ()

void
hb_font_set_ptem (hb_font_t *font,
                  float ptem);

Sets the "point size" of a font. Set to zero to unset. Used in CoreText to implement optical sizing.

Note: There are 72 points in an inch.

Parameters

font

hb_font_t to work upon

 

ptem

font size in points.

 

Since: 1.6.0


hb_font_set_scale ()

void
hb_font_set_scale (hb_font_t *font,
                   int x_scale,
                   int y_scale);

Sets the horizontal and vertical scale of a font.

Parameters

font

hb_font_t to work upon

 

x_scale

Horizontal scale value to assign

 

y_scale

Vertical scale value to assign

 

Since: 0.9.2


hb_font_set_synthetic_slant ()

void
hb_font_set_synthetic_slant (hb_font_t *font,
                             float slant);

Sets the "synthetic slant" of a font. By default is zero. Synthetic slant is the graphical skew applied to the font at rendering time.

HarfBuzz needs to know this value to adjust shaping results, metrics, and style values to match the slanted rendering.

Note: The glyph shape fetched via the hb_font_get_glyph_shape() is slanted to reflect this value as well.
Note: The slant value is a ratio. For example, a 20% slant would be represented as a 0.2 value.

Parameters

font

hb_font_t to work upon

 

slant

synthetic slant value.

 

Since: 3.3.0


hb_font_set_user_data ()

hb_bool_t
hb_font_set_user_data (hb_font_t *font,
                       hb_user_data_key_t *key,
                       void *data,
                       hb_destroy_func_t destroy,
                       hb_bool_t replace);

Attaches a user-data key/data pair to the specified font object.

[skip]

Parameters

font

hb_font_t to work upon

 

key

The user-data key

 

data

A pointer to the user data

 

destroy

A callback to call when data is not needed anymore.

[nullable]

replace

Whether to replace an existing data with the same key

 

Returns

true if success, false otherwise

Since: 0.9.2


hb_font_set_variations ()

void
hb_font_set_variations (hb_font_t *font,
                        const hb_variation_t *variations,
                        unsigned int variations_length);

Applies a list of font-variation settings to a font.

Note that this overrides all existing variations set on font . Axes not included in variations will be effectively set to their default values.

Parameters

font

hb_font_t to work upon

 

variations

Array of variation settings to apply.

[array length=variations_length]

variations_length

Number of variations to apply

 

Since: 1.4.2


hb_font_set_var_coords_design ()

void
hb_font_set_var_coords_design (hb_font_t *font,
                               const float *coords,
                               unsigned int coords_length);

Applies a list of variation coordinates (in design-space units) to a font.

Note that this overrides all existing variations set on font . Axes not included in coords will be effectively set to their default values.

Parameters

font

hb_font_t to work upon

 

coords

Array of variation coordinates to apply.

[array length=coords_length]

coords_length

Number of coordinates to apply

 

Since: 1.4.2


hb_font_set_var_coords_normalized ()

void
hb_font_set_var_coords_normalized (hb_font_t *font,
                                   const int *coords,
                                   unsigned int coords_length);

Applies a list of variation coordinates (in normalized units) to a font.

Note that this overrides all existing variations set on font . Axes not included in coords will be effectively set to their default values.

Note: Coordinates should be normalized to 2.14.

Parameters

font

hb_font_t to work upon

 

coords

Array of variation coordinates to apply.

[array length=coords_length]

coords_length

Number of coordinates to apply

 

Since: 1.4.2


hb_font_set_var_named_instance ()

void
hb_font_set_var_named_instance (hb_font_t *font,
                                unsigned  instance_index);

Sets design coords of a font from a named instance index.

Parameters

font

a font.

 

instance_index

named instance index.

 

Since: 2.6.0


hb_font_subtract_glyph_origin_for_direction ()

void
hb_font_subtract_glyph_origin_for_direction
                               (hb_font_t *font,
                                hb_codepoint_t glyph,
                                hb_direction_t direction,
                                hb_position_t *x,
                                hb_position_t *y);

Subtracts the origin coordinates from an (X,Y) point coordinate, in the specified glyph ID in the specified font.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

glyph

The glyph ID to query

 

direction

The direction of the text segment

 

x

Input = The original X coordinate Output = The X coordinate minus the X-coordinate of the origin.

[inout]

y

Input = The original Y coordinate Output = The Y coordinate minus the Y-coordinate of the origin.

[inout]

Since: 0.9.2


hb_reference_table_func_t ()

hb_blob_t *
(*hb_reference_table_func_t) (hb_face_t *face,
                              hb_tag_t tag,
                              void *user_data);

Callback function for hb_face_create_for_tables().

Parameters

face

an hb_face_t to reference table for

 

tag

the tag of the table to reference

 

user_data

User data pointer passed by the caller

 

Returns

A pointer to the tag table within face .

[transfer full]

Since: 0.9.2


hb_font_funcs_set_font_h_extents_func ()

void
hb_font_funcs_set_font_h_extents_func (hb_font_funcs_t *ffuncs,
                                       hb_font_get_font_h_extents_func_t func,
                                       void *user_data,
                                       hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_font_h_extents_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 1.1.2


hb_font_funcs_set_font_v_extents_func ()

void
hb_font_funcs_set_font_v_extents_func (hb_font_funcs_t *ffuncs,
                                       hb_font_get_font_v_extents_func_t func,
                                       void *user_data,
                                       hb_destroy_func_t destroy);

Sets the implementation function for hb_font_get_font_v_extents_func_t.

Parameters

ffuncs

A font-function structure

 

func

The callback function to assign.

[closure user_data][destroy destroy][scope notified]

user_data

Data to pass to func

 

destroy

The function to call when user_data is not needed anymore.

[nullable]

Since: 1.1.2


hb_font_get_extents_for_direction ()

void
hb_font_get_extents_for_direction (hb_font_t *font,
                                   hb_direction_t direction,
                                   hb_font_extents_t *extents);

Fetches the extents for a font in a text segment of the specified direction.

Calls the appropriate direction-specific variant (horizontal or vertical) depending on the value of direction .

Parameters

font

hb_font_t to work upon

 

direction

The direction of the text segment

 

extents

The hb_font_extents_t retrieved.

[out]

Since: 1.1.3


hb_font_get_font_extents_func_t ()

hb_bool_t
(*hb_font_get_font_extents_func_t) (hb_font_t *font,
                                    void *font_data,
                                    hb_font_extents_t *extents,
                                    void *user_data);

This method should retrieve the extents for a font.

Parameters

font

hb_font_t to work upon

 

font_data

font user data pointer

 

extents

The font extents retrieved.

[out]

user_data

User data pointer passed by the caller

 

hb_font_get_h_extents ()

hb_bool_t
hb_font_get_h_extents (hb_font_t *font,
                       hb_font_extents_t *extents);

Fetches the extents for a specified font, for horizontal text segments.

Parameters

font

hb_font_t to work upon

 

extents

The font extents retrieved.

[out]

Returns

true if data found, false otherwise

Since: 1.1.3


hb_font_get_v_extents ()

hb_bool_t
hb_font_get_v_extents (hb_font_t *font,
                       hb_font_extents_t *extents);

Fetches the extents for a specified font, for vertical text segments.

Parameters

font

hb_font_t to work upon

 

extents

The font extents retrieved.

[out]

Returns

true if data found, false otherwise

Since: 1.1.3

Types and Values

hb_font_funcs_t

typedef struct hb_font_funcs_t hb_font_funcs_t;

Data type containing a set of virtual methods used for working on hb_font_t font objects.

HarfBuzz provides a lightweight default function for each of the methods in hb_font_funcs_t. Client programs can implement their own replacements for the individual font functions, as needed, and replace the default by calling the setter for a method.


hb_font_get_glyph_h_advance_func_t

typedef hb_font_get_glyph_advance_func_t hb_font_get_glyph_h_advance_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the advance for a specified glyph, in horizontal-direction text segments. Advances must be returned in an hb_position_t output parameter.


hb_font_get_glyph_h_advances_func_t

typedef hb_font_get_glyph_advances_func_t hb_font_get_glyph_h_advances_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the advances for a sequence of glyphs, in horizontal-direction text segments.


hb_font_get_glyph_h_kerning_func_t

typedef hb_font_get_glyph_kerning_func_t hb_font_get_glyph_h_kerning_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the kerning-adjustment value for a glyph-pair in the specified font, for horizontal text segments.


hb_font_get_glyph_h_origin_func_t

typedef hb_font_get_glyph_origin_func_t hb_font_get_glyph_h_origin_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the (X,Y) coordinates (in font units) of the origin for a glyph, for horizontal-direction text segments. Each coordinate must be returned in an hb_position_t output parameter.


hb_font_get_glyph_v_advance_func_t

typedef hb_font_get_glyph_advance_func_t hb_font_get_glyph_v_advance_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the advance for a specified glyph, in vertical-direction text segments. Advances must be returned in an hb_position_t output parameter.


hb_font_get_glyph_v_advances_func_t

typedef hb_font_get_glyph_advances_func_t hb_font_get_glyph_v_advances_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the advances for a sequence of glyphs, in vertical-direction text segments.


hb_font_get_glyph_v_origin_func_t

typedef hb_font_get_glyph_origin_func_t hb_font_get_glyph_v_origin_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the (X,Y) coordinates (in font units) of the origin for a glyph, for vertical-direction text segments. Each coordinate must be returned in an hb_position_t output parameter.


hb_font_t

typedef struct hb_font_t hb_font_t;

Data type for holding fonts.


hb_font_get_font_h_extents_func_t

typedef hb_font_get_font_extents_func_t hb_font_get_font_h_extents_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the extents for a font, for horizontal-direction text segments. Extents must be returned in an hb_glyph_extents output parameter.


hb_font_get_font_v_extents_func_t

typedef hb_font_get_font_extents_func_t hb_font_get_font_v_extents_func_t;

A virtual method for the hb_font_funcs_t of an hb_font_t object.

This method should retrieve the extents for a font, for vertical-direction text segments. Extents must be returned in an hb_glyph_extents output parameter.


hb_font_extents_t

typedef struct {
  hb_position_t ascender;
  hb_position_t descender;
  hb_position_t line_gap;
} hb_font_extents_t;

Font-wide extent values, measured in font units.

Note that typically ascender is positive and descender negative, in coordinate systems that grow up.

Members

hb_position_t ascender;

The height of typographic ascenders.

 

hb_position_t descender;

The depth of typographic descenders.

 

hb_position_t line_gap;

The suggested line-spacing gap.

 

hb_glyph_extents_t

typedef struct {
  hb_position_t x_bearing;
  hb_position_t y_bearing;
  hb_position_t width;
  hb_position_t height;
} hb_glyph_extents_t;

Glyph extent values, measured in font units.

Note that height is negative, in coordinate systems that grow up.

Members

hb_position_t x_bearing;

Distance from the x-origin to the left extremum of the glyph.

 

hb_position_t y_bearing;

Distance from the top extremum of the glyph to the y-origin.

 

hb_position_t width;

Distance from the left extremum of the glyph to the right extremum.

 

hb_position_t height;

Distance from the top extremum of the glyph to the bottom extremum.