gfx/harfbuzz/src/hb-ft.h

   1 /*
   2  * Copyright © 2009  Red Hat, Inc.
   3  * Copyright © 2015  Google, Inc.
   4  *
   5  *  This is part of HarfBuzz, a text shaping library.
   6  *
   7  * Permission is hereby granted, without written agreement and without
   8  * license or royalty fees, to use, copy, modify, and distribute this
   9  * software and its documentation for any purpose, provided that the
  10  * above copyright notice and the following two paragraphs appear in
  11  * all copies of this software.
  12  *
  13  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  14  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  15  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  16  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  17  * DAMAGE.
  18  *
  19  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  20  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  21  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  22  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  23  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  24  *
  25  * Red Hat Author(s): Behdad Esfahbod
  26  * Google Author(s): Behdad Esfahbod
  27  */
  28
  29 #ifndef HB_FT_H
  30 #define HB_FT_H
  31
  32 #include "hb.h"
  33
  34 #include <ft2build.h>
  35 #include FT_FREETYPE_H
  36
  37 HB_BEGIN_DECLS
  38
  39 /*
  40  * Note: FreeType is not thread-safe.
  41  * Hence, these functions are not either.
  42  */
  43
  44 /*
  45  * hb-face from ft-face.
  46  */
  47
  48 /* This one creates a new hb-face for given ft-face.
  49  * When the returned hb-face is destroyed, the destroy
  50  * callback is called (if not NULL), with the ft-face passed
  51  * to it.
  52  *
  53  * The client is responsible to make sure that ft-face is
  54  * destroyed after hb-face is destroyed.
  55  *
  56  * Most often you don't want this function.  You should use either
  57  * hb_ft_face_create_cached(), or hb_ft_face_create_referenced().
  58  * In particular, if you are going to pass NULL as destroy, you
  59  * probably should use (the more recent) hb_ft_face_create_referenced()
  60  * instead.
  61  */
  62 HB_EXTERN hb_face_t *
  63 hb_ft_face_create (FT_Face           ft_face,
  64                    hb_destroy_func_t destroy);
  65
  66 /* This version is like hb_ft_face_create(), except that it caches
  67  * the hb-face using the generic pointer of the ft-face.  This means
  68  * that subsequent calls to this function with the same ft-face will
  69  * return the same hb-face (correctly referenced).
  70  *
  71  * Client is still responsible for making sure that ft-face is destroyed
  72  * after hb-face is.
  73  */
  74 HB_EXTERN hb_face_t *
  75 hb_ft_face_create_cached (FT_Face ft_face);
  76
  77 /* This version is like hb_ft_face_create(), except that it calls
  78  * FT_Reference_Face() on ft-face, as such keeping ft-face alive
  79  * as long as the hb-face is.
  80  *
  81  * This is the most convenient version to use.  Use it unless you have
  82  * very good reasons not to.
  83  */
  84 HB_EXTERN hb_face_t *
  85 hb_ft_face_create_referenced (FT_Face ft_face);
  86
  87
  88 /*
  89  * hb-font from ft-face.
  90  */
  91
  92 /*
  93  * Note:
  94  *
  95  * Set face size on ft-face before creating hb-font from it.
  96  * Otherwise hb-ft would NOT pick up the font size correctly.
  97  */
  98
  99 /* See notes on hb_ft_face_create().  Same issues re lifecycle-management
 100  * apply here.  Use hb_ft_font_create_referenced() if you can. */
 101 HB_EXTERN hb_font_t *
 102 hb_ft_font_create (FT_Face           ft_face,
 103                    hb_destroy_func_t destroy);
 104
 105 /* See notes on hb_ft_face_create_referenced() re lifecycle-management
 106  * issues. */
 107 HB_EXTERN hb_font_t *
 108 hb_ft_font_create_referenced (FT_Face ft_face);
 109
 110 HB_EXTERN FT_Face
 111 hb_ft_font_get_face (hb_font_t *font);
 112
 113 HB_EXTERN FT_Face
 114 hb_ft_font_lock_face (hb_font_t *font);
 115
 116 HB_EXTERN void
 117 hb_ft_font_unlock_face (hb_font_t *font);
 118
 119 HB_EXTERN void
 120 hb_ft_font_set_load_flags (hb_font_t *font, int load_flags);
 121
 122 HB_EXTERN int
 123 hb_ft_font_get_load_flags (hb_font_t *font);
 124
 125 /* Call when size or variations settings on underlying FT_Face changed,
 126  * and you want to update the hb_font_t from it. */
 127 HB_EXTERN void
 128 hb_ft_font_changed (hb_font_t *font);
 129
 130 /* Call when size or variations settings on underlying hb_font_t may have
 131  * changed, and you want to update the FT_Face from it.  This call is fast
 132  * if nothing changed on hb_font_t. Returns true if changed. */
 133 HB_EXTERN hb_bool_t
 134 hb_ft_hb_font_changed (hb_font_t *font);
 135
 136 /* Makes an hb_font_t use FreeType internally to implement font functions.
 137  * Note: this internally creates an FT_Face.  Use it when you create your
 138  * hb_face_t using hb_face_create(). */
 139 HB_EXTERN void
 140 hb_ft_font_set_funcs (hb_font_t *font);
 141
 142
 143 HB_END_DECLS
 144
 145 #endif /* HB_FT_H */