src/hb-ot-metrics.h

   1 /*
   2  * Copyright © 2018  Ebrahim Byagowi
   3  *
   4  *  This is part of HarfBuzz, a text shaping library.
   5  *
   6  * Permission is hereby granted, without written agreement and without
   7  * license or royalty fees, to use, copy, modify, and distribute this
   8  * software and its documentation for any purpose, provided that the
   9  * above copyright notice and the following two paragraphs appear in
  10  * all copies of this software.
  11  *
  12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  16  * DAMAGE.
  17  *
  18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  23  */
  24
  25 #ifndef HB_OT_H_IN
  26 #error "Include <hb-ot.h> instead."
  27 #endif
  28
  29 #ifndef HB_OT_METRICS_H
  30 #define HB_OT_METRICS_H
  31
  32 #include "hb.h"
  33 #include "hb-ot-name.h"
  34
  35 HB_BEGIN_DECLS
  36
  37
  38 /**
  39  * hb_ot_metrics_tag_t:
  40  * @HB_OT_METRICS_TAG_HORIZONTAL_ASCENDER: horizontal ascender.
  41  * @HB_OT_METRICS_TAG_HORIZONTAL_DESCENDER: horizontal descender.
  42  * @HB_OT_METRICS_TAG_HORIZONTAL_LINE_GAP: horizontal line gap.
  43  * @HB_OT_METRICS_TAG_HORIZONTAL_CLIPPING_ASCENT: horizontal clipping ascent.
  44  * @HB_OT_METRICS_TAG_HORIZONTAL_CLIPPING_DESCENT: horizontal clipping descent.
  45  * @HB_OT_METRICS_TAG_VERTICAL_ASCENDER: vertical ascender.
  46  * @HB_OT_METRICS_TAG_VERTICAL_DESCENDER: vertical descender.
  47  * @HB_OT_METRICS_TAG_VERTICAL_LINE_GAP: vertical line gap.
  48  * @HB_OT_METRICS_TAG_HORIZONTAL_CARET_RISE: horizontal caret rise.
  49  * @HB_OT_METRICS_TAG_HORIZONTAL_CARET_RUN: horizontal caret run.
  50  * @HB_OT_METRICS_TAG_HORIZONTAL_CARET_OFFSET: horizontal caret offset.
  51  * @HB_OT_METRICS_TAG_VERTICAL_CARET_RISE: vertical caret rise.
  52  * @HB_OT_METRICS_TAG_VERTICAL_CARET_RUN: vertical caret run.
  53  * @HB_OT_METRICS_TAG_VERTICAL_CARET_OFFSET: vertical caret offset.
  54  * @HB_OT_METRICS_TAG_X_HEIGHT: x height.
  55  * @HB_OT_METRICS_TAG_CAP_HEIGHT: cap height.
  56  * @HB_OT_METRICS_TAG_SUBSCRIPT_EM_X_SIZE: subscript em x size.
  57  * @HB_OT_METRICS_TAG_SUBSCRIPT_EM_Y_SIZE: subscript em y size.
  58  * @HB_OT_METRICS_TAG_SUBSCRIPT_EM_X_OFFSET: subscript em x offset.
  59  * @HB_OT_METRICS_TAG_SUBSCRIPT_EM_Y_OFFSET: subscript em y offset.
  60  * @HB_OT_METRICS_TAG_SUPERSCRIPT_EM_X_SIZE: superscript em x size.
  61  * @HB_OT_METRICS_TAG_SUPERSCRIPT_EM_Y_SIZE: superscript em y size.
  62  * @HB_OT_METRICS_TAG_SUPERSCRIPT_EM_X_OFFSET: superscript em x offset.
  63  * @HB_OT_METRICS_TAG_SUPERSCRIPT_EM_Y_OFFSET: superscript em y offset.
  64  * @HB_OT_METRICS_TAG_STRIKEOUT_SIZE: strikeout size.
  65  * @HB_OT_METRICS_TAG_STRIKEOUT_OFFSET: strikeout offset.
  66  * @HB_OT_METRICS_TAG_UNDERLINE_SIZE: underline size.
  67  * @HB_OT_METRICS_TAG_UNDERLINE_OFFSET: underline offset.
  68  *
  69  * From https://docs.microsoft.com/en-us/typography/opentype/spec/mvar#value-tags
  70  *
  71  * Since: 2.6.0
  72  **/
  73 typedef enum {
  74   HB_OT_METRICS_TAG_HORIZONTAL_ASCENDER         = HB_TAG ('h','a','s','c'),
  75   HB_OT_METRICS_TAG_HORIZONTAL_DESCENDER        = HB_TAG ('h','d','s','c'),
  76   HB_OT_METRICS_TAG_HORIZONTAL_LINE_GAP         = HB_TAG ('h','l','g','p'),
  77   HB_OT_METRICS_TAG_HORIZONTAL_CLIPPING_ASCENT  = HB_TAG ('h','c','l','a'),
  78   HB_OT_METRICS_TAG_HORIZONTAL_CLIPPING_DESCENT = HB_TAG ('h','c','l','d'),
  79   HB_OT_METRICS_TAG_VERTICAL_ASCENDER           = HB_TAG ('v','a','s','c'),
  80   HB_OT_METRICS_TAG_VERTICAL_DESCENDER          = HB_TAG ('v','d','s','c'),
  81   HB_OT_METRICS_TAG_VERTICAL_LINE_GAP           = HB_TAG ('v','l','g','p'),
  82   HB_OT_METRICS_TAG_HORIZONTAL_CARET_RISE       = HB_TAG ('h','c','r','s'),
  83   HB_OT_METRICS_TAG_HORIZONTAL_CARET_RUN        = HB_TAG ('h','c','r','n'),
  84   HB_OT_METRICS_TAG_HORIZONTAL_CARET_OFFSET     = HB_TAG ('h','c','o','f'),
  85   HB_OT_METRICS_TAG_VERTICAL_CARET_RISE         = HB_TAG ('v','c','r','s'),
  86   HB_OT_METRICS_TAG_VERTICAL_CARET_RUN          = HB_TAG ('v','c','r','n'),
  87   HB_OT_METRICS_TAG_VERTICAL_CARET_OFFSET       = HB_TAG ('v','c','o','f'),
  88   HB_OT_METRICS_TAG_X_HEIGHT                    = HB_TAG ('x','h','g','t'),
  89   HB_OT_METRICS_TAG_CAP_HEIGHT                  = HB_TAG ('c','p','h','t'),
  90   HB_OT_METRICS_TAG_SUBSCRIPT_EM_X_SIZE         = HB_TAG ('s','b','x','s'),
  91   HB_OT_METRICS_TAG_SUBSCRIPT_EM_Y_SIZE         = HB_TAG ('s','b','y','s'),
  92   HB_OT_METRICS_TAG_SUBSCRIPT_EM_X_OFFSET       = HB_TAG ('s','b','x','o'),
  93   HB_OT_METRICS_TAG_SUBSCRIPT_EM_Y_OFFSET       = HB_TAG ('s','b','y','o'),
  94   HB_OT_METRICS_TAG_SUPERSCRIPT_EM_X_SIZE       = HB_TAG ('s','p','x','s'),
  95   HB_OT_METRICS_TAG_SUPERSCRIPT_EM_Y_SIZE       = HB_TAG ('s','p','y','s'),
  96   HB_OT_METRICS_TAG_SUPERSCRIPT_EM_X_OFFSET     = HB_TAG ('s','p','x','o'),
  97   HB_OT_METRICS_TAG_SUPERSCRIPT_EM_Y_OFFSET     = HB_TAG ('s','p','y','o'),
  98   HB_OT_METRICS_TAG_STRIKEOUT_SIZE              = HB_TAG ('s','t','r','s'),
  99   HB_OT_METRICS_TAG_STRIKEOUT_OFFSET            = HB_TAG ('s','t','r','o'),
 100   HB_OT_METRICS_TAG_UNDERLINE_SIZE              = HB_TAG ('u','n','d','s'),
 101   HB_OT_METRICS_TAG_UNDERLINE_OFFSET            = HB_TAG ('u','n','d','o'),
 102
 103   _HB_OT_METRICS_TAG_MAX_VALUE = HB_TAG_MAX_SIGNED /*< skip >*/
 104 } hb_ot_metrics_tag_t;
 105
 106 HB_EXTERN hb_bool_t
 107 hb_ot_metrics_get_position (hb_font_t           *font,
 108                             hb_ot_metrics_tag_t  metrics_tag,
 109                             hb_position_t       *position     /* OUT.  May be NULL. */);
 110
 111 HB_EXTERN float
 112 hb_ot_metrics_get_variation (hb_font_t *font, hb_ot_metrics_tag_t metrics_tag);
 113
 114 HB_EXTERN hb_position_t
 115 hb_ot_metrics_get_x_variation (hb_font_t *font, hb_ot_metrics_tag_t metrics_tag);
 116
 117 HB_EXTERN hb_position_t
 118 hb_ot_metrics_get_y_variation (hb_font_t *font, hb_ot_metrics_tag_t metrics_tag);
 119
 120 HB_END_DECLS
 121
 122 #endif /* HB_OT_METRICS_H */