xref: /aosp_15_r20/external/harfbuzz_ng/src/hb-ot-hhea-table.hh (revision 2d1272b857b1f7575e6e246373e1cb218663db8a)
1 /*
2  * Copyright © 2011,2012  Google, Inc.
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  * Google Author(s): Behdad Esfahbod
25  */
26 
27 #ifndef HB_OT_HHEA_TABLE_HH
28 #define HB_OT_HHEA_TABLE_HH
29 
30 #include "hb-open-type.hh"
31 
32 /*
33  * hhea -- Horizontal Header
34  * https://docs.microsoft.com/en-us/typography/opentype/spec/hhea
35  * vhea -- Vertical Header
36  * https://docs.microsoft.com/en-us/typography/opentype/spec/vhea
37  */
38 #define HB_OT_TAG_hhea HB_TAG('h','h','e','a')
39 #define HB_OT_TAG_vhea HB_TAG('v','h','e','a')
40 
41 
42 namespace OT {
43 
44 
45 template <typename T>
46 struct _hea
47 {
has_dataOT::_hea48   bool has_data () const { return version.major; }
49 
sanitizeOT::_hea50   bool sanitize (hb_sanitize_context_t *c) const
51   {
52     TRACE_SANITIZE (this);
53     return_trace (c->check_struct (this) &&
54 		  hb_barrier () &&
55 		  likely (version.major == 1));
56   }
57 
58   public:
59   FixedVersion<>version;	/* 0x00010000u for version 1.0. */
60   FWORD		ascender;	/* Typographic ascent. */
61   FWORD		descender;	/* Typographic descent. */
62   FWORD		lineGap;	/* Typographic line gap. */
63   UFWORD	advanceMax;	/* Maximum advance width/height value in
64 				 * metrics table. */
65   FWORD		minLeadingBearing;
66 				/* Minimum left/top sidebearing value in
67 				 * metrics table. */
68   FWORD		minTrailingBearing;
69 				/* Minimum right/bottom sidebearing value;
70 				 * calculated as Min(aw - lsb -
71 				 * (xMax - xMin)) for horizontal. */
72   FWORD		maxExtent;	/* horizontal: Max(lsb + (xMax - xMin)),
73 				 * vertical: minLeadingBearing+(yMax-yMin). */
74   HBINT16	caretSlopeRise;	/* Used to calculate the slope of the
75 				 * cursor (rise/run); 1 for vertical caret,
76 				 * 0 for horizontal.*/
77   HBINT16	caretSlopeRun;	/* 0 for vertical caret, 1 for horizontal. */
78   HBINT16	caretOffset;	/* The amount by which a slanted
79 				 * highlight on a glyph needs
80 				 * to be shifted to produce the
81 				 * best appearance. Set to 0 for
82 				 * non-slanted fonts. */
83   HBINT16	reserved1;	/* Set to 0. */
84   HBINT16	reserved2;	/* Set to 0. */
85   HBINT16	reserved3;	/* Set to 0. */
86   HBINT16	reserved4;	/* Set to 0. */
87   HBINT16	metricDataFormat;/* 0 for current format. */
88   HBUINT16	numberOfLongMetrics;
89 				/* Number of LongMetric entries in metric
90 				 * table. */
91   public:
92   DEFINE_SIZE_STATIC (36);
93 };
94 
95 struct hhea : _hea<hhea> {
96   static constexpr hb_tag_t tableTag = HB_OT_TAG_hhea;
97 };
98 struct vhea : _hea<vhea> {
99   static constexpr hb_tag_t tableTag = HB_OT_TAG_vhea;
100 };
101 
102 
103 } /* namespace OT */
104 
105 
106 #endif /* HB_OT_HHEA_TABLE_HH */
107