--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/harfbuzz/src/hb-font.h	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,1108 @@
+/*
+ * Copyright © 2009  Red Hat, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Red Hat Author(s): Behdad Esfahbod
+ */
+
+#if !defined(HB_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR)
+#error "Include <hb.h> instead."
+#endif
+
+#ifndef HB_FONT_H
+#define HB_FONT_H
+
+#include "hb-common.h"
+#include "hb-face.h"
+#include "hb-draw.h"
+
+HB_BEGIN_DECLS
+
+/**
+ * hb_font_t:
+ *
+ * Data type for holding fonts.
+ *
+ */
+typedef struct hb_font_t hb_font_t;
+
+
+/*
+ * 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.
+ *
+ **/
+typedef struct hb_font_funcs_t hb_font_funcs_t;
+
+HB_EXTERN hb_font_funcs_t *
+hb_font_funcs_create (void);
+
+HB_EXTERN hb_font_funcs_t *
+hb_font_funcs_get_empty (void);
+
+HB_EXTERN hb_font_funcs_t *
+hb_font_funcs_reference (hb_font_funcs_t *ffuncs);
+
+HB_EXTERN void
+hb_font_funcs_destroy (hb_font_funcs_t *ffuncs);
+
+HB_EXTERN 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);
+
+
+HB_EXTERN void *
+hb_font_funcs_get_user_data (const hb_font_funcs_t *ffuncs,
+			     hb_user_data_key_t    *key);
+
+
+HB_EXTERN void
+hb_font_funcs_make_immutable (hb_font_funcs_t *ffuncs);
+
+HB_EXTERN hb_bool_t
+hb_font_funcs_is_immutable (hb_font_funcs_t *ffuncs);
+
+
+/* font and glyph extents */
+
+/**
+ * hb_font_extents_t:
+ * @ascender: The height of typographic ascenders.
+ * @descender: The depth of typographic descenders.
+ * @line_gap: The suggested line-spacing gap.
+ *
+ * Font-wide extent values, measured in font units.
+ *
+ * Note that typically @ascender is positive and @descender
+ * negative, in coordinate systems that grow up.
+ **/
+typedef struct hb_font_extents_t {
+  hb_position_t ascender;
+  hb_position_t descender;
+  hb_position_t line_gap;
+  /*< private >*/
+  hb_position_t reserved9;
+  hb_position_t reserved8;
+  hb_position_t reserved7;
+  hb_position_t reserved6;
+  hb_position_t reserved5;
+  hb_position_t reserved4;
+  hb_position_t reserved3;
+  hb_position_t reserved2;
+  hb_position_t reserved1;
+} hb_font_extents_t;
+
+/**
+ * hb_glyph_extents_t:
+ * @x_bearing: Distance from the x-origin to the left extremum of the glyph.
+ * @y_bearing: Distance from the top extremum of the glyph to the y-origin.
+ * @width: Distance from the left extremum of the glyph to the right extremum.
+ * @height: Distance from the top extremum of the glyph to the bottom extremum.
+ *
+ * Glyph extent values, measured in font units.
+ *
+ * Note that @height is negative, in coordinate systems that grow up.
+ **/
+typedef struct hb_glyph_extents_t {
+  hb_position_t x_bearing;
+  hb_position_t y_bearing;
+  hb_position_t width;
+  hb_position_t height;
+} hb_glyph_extents_t;
+
+/* func types */
+
+/**
+ * hb_font_get_font_extents_func_t:
+ * @font: #hb_font_t to work upon
+ * @font_data: @font user data pointer
+ * @extents: (out): The font extents retrieved
+ * @user_data: User data pointer passed by the caller
+ *
+ * This method should retrieve the extents for a font.
+ *
+ **/
+typedef 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);
+
+/**
+ * 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.
+ * 
+ **/
+typedef hb_font_get_font_extents_func_t hb_font_get_font_h_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.
+ * 
+ **/
+typedef hb_font_get_font_extents_func_t hb_font_get_font_v_extents_func_t;
+
+
+/**
+ * hb_font_get_nominal_glyph_func_t:
+ * @font: #hb_font_t to work upon
+ * @font_data: @font user data pointer
+ * @unicode: The Unicode code point to query
+ * @glyph: (out): The glyph ID retrieved
+ * @user_data: User data pointer passed by the caller
+ *
+ * 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.
+ * 
+ * Return value: `true` if data found, `false` otherwise
+ *
+ **/
+typedef 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);
+
+/**
+ * hb_font_get_variation_glyph_func_t:
+ * @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: (out): The glyph ID retrieved
+ * @user_data: User data pointer passed by the caller
+ *
+ * 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.
+ * 
+ * Return value: `true` if data found, `false` otherwise
+ *
+ **/
+typedef 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);
+
+
+/**
+ * hb_font_get_nominal_glyphs_func_t:
+ * @font: #hb_font_t to work upon
+ * @font_data: @font user data pointer
+ * @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: (out): The first glyph ID retrieved
+ * @glyph_stride: The stride between successive glyph IDs
+ * @user_data: User data pointer passed by the caller
+ *
+ * A virtual method for the #hb_font_funcs_t of an #hb_font_t object.
+ *
+ * This method should retrieve the nominal glyph IDs for a sequence of
+ * Unicode code points. Glyph IDs must be returned in a #hb_codepoint_t
+ * output parameter.
+ *
+ * Return value: the number of code points processed
+ * 
+ **/
+typedef unsigned int (*hb_font_get_nominal_glyphs_func_t) (hb_font_t *font, void *font_data,
+							   unsigned int count,
+							   const hb_codepoint_t *first_unicode,
+							   unsigned int unicode_stride,
+							   hb_codepoint_t *first_glyph,
+							   unsigned int glyph_stride,
+							   void *user_data);
+
+/**
+ * hb_font_get_glyph_advance_func_t:
+ * @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
+ *
+ * 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.
+ * 
+ * Return value: The advance of @glyph within @font
+ *
+ **/
+typedef hb_position_t (*hb_font_get_glyph_advance_func_t) (hb_font_t *font, void *font_data,
+							   hb_codepoint_t glyph,
+							   void *user_data);
+
+/**
+ * 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.
+ * 
+ **/
+typedef hb_font_get_glyph_advance_func_t hb_font_get_glyph_h_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.
+ * 
+ **/
+typedef hb_font_get_glyph_advance_func_t hb_font_get_glyph_v_advance_func_t;
+
+/**
+ * hb_font_get_glyph_advances_func_t:
+ * @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: (out): The first advance retrieved
+ * @advance_stride: The stride between successive advances
+ * @user_data: User data pointer passed by the caller
+ *
+ * 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.
+ * 
+ **/
+typedef 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);
+
+/**
+ * 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.
+ * 
+ **/
+typedef hb_font_get_glyph_advances_func_t hb_font_get_glyph_h_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.
+ * 
+ **/
+typedef hb_font_get_glyph_advances_func_t hb_font_get_glyph_v_advances_func_t;
+
+/**
+ * hb_font_get_glyph_origin_func_t:
+ * @font: #hb_font_t to work upon
+ * @font_data: @font user data pointer
+ * @glyph: The glyph ID to query
+ * @x: (out): The X coordinate of the origin
+ * @y: (out): The Y coordinate of the origin
+ * @user_data: User data pointer passed by the caller
+ *
+ * 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.
+ *
+ * Return value: `true` if data found, `false` otherwise
+ * 
+ **/
+typedef 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);
+
+/**
+ * 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.
+ * 
+ **/
+typedef hb_font_get_glyph_origin_func_t hb_font_get_glyph_h_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.
+ * 
+ **/
+typedef hb_font_get_glyph_origin_func_t hb_font_get_glyph_v_origin_func_t;
+
+/**
+ * hb_font_get_glyph_kerning_func_t:
+ * @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
+ *
+ * This method should retrieve the kerning-adjustment value for a glyph-pair in
+ * the specified font, for horizontal text segments.
+ *
+ **/
+typedef 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);
+/**
+ * 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.
+ *
+ **/
+typedef hb_font_get_glyph_kerning_func_t hb_font_get_glyph_h_kerning_func_t;
+
+
+/**
+ * hb_font_get_glyph_extents_func_t:
+ * @font: #hb_font_t to work upon
+ * @font_data: @font user data pointer
+ * @glyph: The glyph ID to query
+ * @extents: (out): The #hb_glyph_extents_t retrieved
+ * @user_data: User data pointer passed by the caller
+ *
+ * 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.
+ *
+ * Return value: `true` if data found, `false` otherwise
+ * 
+ **/
+typedef 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);
+
+/**
+ * hb_font_get_glyph_contour_point_func_t:
+ * @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: (out): The X value retrieved for the contour point
+ * @y: (out): The Y value retrieved for the contour point
+ * @user_data: User data pointer passed by the caller
+ *
+ * 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.
+ * 
+ * Return value: `true` if data found, `false` otherwise
+ *
+ **/
+typedef 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);
+
+
+/**
+ * hb_font_get_glyph_name_func_t:
+ * @font: #hb_font_t to work upon
+ * @font_data: @font user data pointer
+ * @glyph: The glyph ID to query
+ * @name: (out) (array length=size): Name string retrieved for the glyph ID
+ * @size: Length of the glyph-name string retrieved
+ * @user_data: User data pointer passed by the caller
+ *
+ * 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.
+ * 
+ * Return value: `true` if data found, `false` otherwise
+ *
+ **/
+typedef 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);
+
+/**
+ * hb_font_get_glyph_from_name_func_t:
+ * @font: #hb_font_t to work upon
+ * @font_data: @font user data pointer
+ * @name: (array length=len): The name string to query
+ * @len: The length of the name queried
+ * @glyph: (out): The glyph ID retrieved
+ * @user_data: User data pointer passed by the caller
+ *
+ * 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. 
+ * 
+ * Return value: `true` if data found, `false` otherwise
+ *
+ **/
+typedef hb_bool_t (*hb_font_get_glyph_from_name_func_t) (hb_font_t *font, void *font_data,
+							 const char *name, int len, /* -1 means nul-terminated */
+							 hb_codepoint_t *glyph,
+							 void *user_data);
+
+/**
+ * hb_font_get_glyph_shape_func_t:
+ * @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
+ *
+ * A virtual method for the #hb_font_funcs_t of an #hb_font_t object.
+ *
+ * Since: 4.0.0
+ *
+ **/
+typedef 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);
+
+
+/* func setters */
+
+/**
+ * hb_font_funcs_set_font_h_extents_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_font_h_extents_func_t.
+ *
+ * Since: 1.1.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_font_v_extents_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_font_v_extents_func_t.
+ *
+ * Since: 1.1.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_nominal_glyph_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_nominal_glyph_func_t.
+ *
+ * Since: 1.2.3
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_nominal_glyphs_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_nominal_glyphs_func_t.
+ *
+ * Since: 2.0.0
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_variation_glyph_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_variation_glyph_func_t.
+ *
+ * Since: 1.2.3
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_h_advance_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_h_advance_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_v_advance_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_v_advance_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_h_advances_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_h_advances_func_t.
+ *
+ * Since: 1.8.6
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_v_advances_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_v_advances_func_t.
+ *
+ * Since: 1.8.6
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_h_origin_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_h_origin_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_v_origin_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_v_origin_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_h_kerning_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_h_kerning_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_extents_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_extents_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_contour_point_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_contour_point_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_name_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_name_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_from_name_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_from_name_func_t.
+ *
+ * Since: 0.9.2
+ **/
+HB_EXTERN 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);
+
+/**
+ * hb_font_funcs_set_glyph_shape_func:
+ * @ffuncs: A font-function structure
+ * @func: (closure user_data) (destroy destroy) (scope notified): The callback function to assign
+ * @user_data: Data to pass to @func
+ * @destroy: (nullable): The function to call when @user_data is not needed anymore
+ *
+ * Sets the implementation function for #hb_font_get_glyph_shape_func_t.
+ *
+ * Since: 4.0.0
+ **/
+HB_EXTERN 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);
+
+/* func dispatch */
+
+HB_EXTERN hb_bool_t
+hb_font_get_h_extents (hb_font_t *font,
+		       hb_font_extents_t *extents);
+HB_EXTERN hb_bool_t
+hb_font_get_v_extents (hb_font_t *font,
+		       hb_font_extents_t *extents);
+
+HB_EXTERN hb_bool_t
+hb_font_get_nominal_glyph (hb_font_t *font,
+			   hb_codepoint_t unicode,
+			   hb_codepoint_t *glyph);
+HB_EXTERN 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);
+
+HB_EXTERN 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);
+
+HB_EXTERN hb_position_t
+hb_font_get_glyph_h_advance (hb_font_t *font,
+			     hb_codepoint_t glyph);
+HB_EXTERN hb_position_t
+hb_font_get_glyph_v_advance (hb_font_t *font,
+			     hb_codepoint_t glyph);
+
+HB_EXTERN 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);
+HB_EXTERN 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);
+
+HB_EXTERN 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);
+HB_EXTERN 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);
+
+HB_EXTERN hb_position_t
+hb_font_get_glyph_h_kerning (hb_font_t *font,
+			     hb_codepoint_t left_glyph, hb_codepoint_t right_glyph);
+
+HB_EXTERN hb_bool_t
+hb_font_get_glyph_extents (hb_font_t *font,
+			   hb_codepoint_t glyph,
+			   hb_glyph_extents_t *extents);
+
+HB_EXTERN 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);
+
+HB_EXTERN hb_bool_t
+hb_font_get_glyph_name (hb_font_t *font,
+			hb_codepoint_t glyph,
+			char *name, unsigned int size);
+HB_EXTERN hb_bool_t
+hb_font_get_glyph_from_name (hb_font_t *font,
+			     const char *name, int len, /* -1 means nul-terminated */
+			     hb_codepoint_t *glyph);
+
+HB_EXTERN void
+hb_font_get_glyph_shape (hb_font_t *font,
+			 hb_codepoint_t glyph,
+			 hb_draw_funcs_t *dfuncs, void *draw_data);
+
+
+/* high-level funcs, with fallback */
+
+/* Calls either hb_font_get_nominal_glyph() if variation_selector is 0,
+ * otherwise calls hb_font_get_variation_glyph(). */
+HB_EXTERN hb_bool_t
+hb_font_get_glyph (hb_font_t *font,
+		   hb_codepoint_t unicode, hb_codepoint_t variation_selector,
+		   hb_codepoint_t *glyph);
+
+HB_EXTERN void
+hb_font_get_extents_for_direction (hb_font_t *font,
+				   hb_direction_t direction,
+				   hb_font_extents_t *extents);
+HB_EXTERN 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);
+HB_EXTERN 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);
+HB_EXTERN 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);
+HB_EXTERN 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);
+HB_EXTERN 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);
+
+HB_EXTERN 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);
+
+HB_EXTERN 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);
+
+HB_EXTERN 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);
+
+/* Generates gidDDD if glyph has no name. */
+HB_EXTERN void
+hb_font_glyph_to_string (hb_font_t *font,
+			 hb_codepoint_t glyph,
+			 char *s, unsigned int size);
+/* Parses gidDDD and uniUUUU strings automatically. */
+HB_EXTERN hb_bool_t
+hb_font_glyph_from_string (hb_font_t *font,
+			   const char *s, int len, /* -1 means nul-terminated */
+			   hb_codepoint_t *glyph);
+
+
+/*
+ * hb_font_t
+ */
+
+/* Fonts are very light-weight objects */
+
+HB_EXTERN hb_font_t *
+hb_font_create (hb_face_t *face);
+
+HB_EXTERN hb_font_t *
+hb_font_create_sub_font (hb_font_t *parent);
+
+HB_EXTERN hb_font_t *
+hb_font_get_empty (void);
+
+HB_EXTERN hb_font_t *
+hb_font_reference (hb_font_t *font);
+
+HB_EXTERN void
+hb_font_destroy (hb_font_t *font);
+
+HB_EXTERN 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);
+
+
+HB_EXTERN void *
+hb_font_get_user_data (const hb_font_t    *font,
+		       hb_user_data_key_t *key);
+
+HB_EXTERN void
+hb_font_make_immutable (hb_font_t *font);
+
+HB_EXTERN hb_bool_t
+hb_font_is_immutable (hb_font_t *font);
+
+HB_EXTERN unsigned int
+hb_font_get_serial (hb_font_t *font);
+
+HB_EXTERN void
+hb_font_changed (hb_font_t *font);
+
+HB_EXTERN void
+hb_font_set_parent (hb_font_t *font,
+		    hb_font_t *parent);
+
+HB_EXTERN hb_font_t *
+hb_font_get_parent (hb_font_t *font);
+
+HB_EXTERN void
+hb_font_set_face (hb_font_t *font,
+		  hb_face_t *face);
+
+HB_EXTERN hb_face_t *
+hb_font_get_face (hb_font_t *font);
+
+
+HB_EXTERN void
+hb_font_set_funcs (hb_font_t         *font,
+		   hb_font_funcs_t   *klass,
+		   void              *font_data,
+		   hb_destroy_func_t  destroy);
+
+/* Be *very* careful with this function! */
+HB_EXTERN void
+hb_font_set_funcs_data (hb_font_t         *font,
+			void              *font_data,
+			hb_destroy_func_t  destroy);
+
+
+HB_EXTERN void
+hb_font_set_scale (hb_font_t *font,
+		   int x_scale,
+		   int y_scale);
+
+HB_EXTERN void
+hb_font_get_scale (hb_font_t *font,
+		   int *x_scale,
+		   int *y_scale);
+
+/*
+ * A zero value means "no hinting in that direction"
+ */
+HB_EXTERN void
+hb_font_set_ppem (hb_font_t *font,
+		  unsigned int x_ppem,
+		  unsigned int y_ppem);
+
+HB_EXTERN void
+hb_font_get_ppem (hb_font_t *font,
+		  unsigned int *x_ppem,
+		  unsigned int *y_ppem);
+
+/*
+ * Point size per EM.  Used for optical-sizing in CoreText.
+ * A value of zero means "not set".
+ */
+HB_EXTERN void
+hb_font_set_ptem (hb_font_t *font, float ptem);
+
+HB_EXTERN float
+hb_font_get_ptem (hb_font_t *font);
+
+HB_EXTERN void
+hb_font_set_synthetic_slant (hb_font_t *font, float slant);
+
+HB_EXTERN float
+hb_font_get_synthetic_slant (hb_font_t *font);
+
+HB_EXTERN void
+hb_font_set_variations (hb_font_t *font,
+			const hb_variation_t *variations,
+			unsigned int variations_length);
+
+HB_EXTERN void
+hb_font_set_var_coords_design (hb_font_t *font,
+			       const float *coords,
+			       unsigned int coords_length);
+
+HB_EXTERN const float *
+hb_font_get_var_coords_design (hb_font_t *font,
+			       unsigned int *length);
+
+HB_EXTERN void
+hb_font_set_var_coords_normalized (hb_font_t *font,
+				   const int *coords, /* 2.14 normalized */
+				   unsigned int coords_length);
+
+HB_EXTERN const int *
+hb_font_get_var_coords_normalized (hb_font_t *font,
+				   unsigned int *length);
+
+HB_EXTERN void
+hb_font_set_var_named_instance (hb_font_t *font,
+				unsigned instance_index);
+
+
+HB_END_DECLS
+
+#endif /* HB_FONT_H */