mkwebfont_hb-subset 0.5.0

A wrapper for HarfBuzz font subsetting API
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132

/*
 * Copyright © 2022 Behdad Esfahbod
 *
 *  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.
 */

#ifndef HB_PAINT_EXTENTS_HH
#define HB_PAINT_EXTENTS_HH

#include "hb.hh"
#include "hb-paint.h"

#include "hb-geometry.hh"


typedef struct  hb_paint_extents_context_t hb_paint_extents_context_t;

struct hb_paint_extents_context_t
{
  hb_paint_extents_context_t ()
  {
    transforms.push (hb_transform_t{});
    clips.push (hb_bounds_t{hb_bounds_t::UNBOUNDED});
    groups.push (hb_bounds_t{hb_bounds_t::EMPTY});
  }

  hb_extents_t get_extents ()
  {
    return groups.tail().extents;
  }

  bool is_bounded ()
  {
    return groups.tail().status != hb_bounds_t::UNBOUNDED;
  }

  void push_transform (const hb_transform_t &trans)
  {
    hb_transform_t t = transforms.tail ();
    t.multiply (trans);
    transforms.push (t);
  }

  void pop_transform ()
  {
    transforms.pop ();
  }

  void push_clip (hb_extents_t extents)
  {
    /* Transform extents and push a new clip. */
    const hb_transform_t &t = transforms.tail ();
    t.transform_extents (extents);

    clips.push (hb_bounds_t {extents});
  }

  void pop_clip ()
  {
    clips.pop ();
  }

  void push_group ()
  {
    groups.push (hb_bounds_t {hb_bounds_t::EMPTY});
  }

  void pop_group (hb_paint_composite_mode_t mode)
  {
    const hb_bounds_t src_bounds = groups.pop ();
    hb_bounds_t &backdrop_bounds = groups.tail ();

    // https://learn.microsoft.com/en-us/typography/opentype/spec/colr#format-32-paintcomposite
    switch ((int) mode)
    {
      case HB_PAINT_COMPOSITE_MODE_CLEAR:
	backdrop_bounds.status = hb_bounds_t::EMPTY;
	break;
      case HB_PAINT_COMPOSITE_MODE_SRC:
      case HB_PAINT_COMPOSITE_MODE_SRC_OUT:
	backdrop_bounds = src_bounds;
	break;
      case HB_PAINT_COMPOSITE_MODE_DEST:
      case HB_PAINT_COMPOSITE_MODE_DEST_OUT:
	break;
      case HB_PAINT_COMPOSITE_MODE_SRC_IN:
      case HB_PAINT_COMPOSITE_MODE_DEST_IN:
	backdrop_bounds.intersect (src_bounds);
	break;
      default:
	backdrop_bounds.union_ (src_bounds);
	break;
     }
  }

  void paint ()
  {
    const hb_bounds_t &clip = clips.tail ();
    hb_bounds_t &group = groups.tail ();

    group.union_ (clip);
  }

  protected:
  hb_vector_t<hb_transform_t> transforms;
  hb_vector_t<hb_bounds_t> clips;
  hb_vector_t<hb_bounds_t> groups;
};

HB_INTERNAL hb_paint_funcs_t *
hb_paint_extents_get_funcs ();


#endif /* HB_PAINT_EXTENTS_HH */