2 * Copyright © 2010 Red Hat, Inc.
4 * This is part of HarfBuzz, a text shaping library.
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.
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
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.
24 * Red Hat Author(s): Behdad Esfahbod
27 #ifndef HB_OT_HEAD_PRIVATE_HH
28 #define HB_OT_HEAD_PRIVATE_HH
30 #include "hb-open-type-private.hh"
39 #define HB_OT_TAG_head HB_TAG('h','e','a','d')
43 static const hb_tag_t Tag = HB_OT_TAG_head;
45 inline unsigned int get_upem (void) const {
46 unsigned int upem = unitsPerEm;
47 /* If no valid head table found, assume 1000, which matches typicaly Type1 usage. */
48 return 16 <= upem && upem <= 16384 ? upem : 1000;
51 inline bool sanitize (hb_sanitize_context_t *c) {
53 return c->check_struct (this) && likely (version.major == 1);
57 FixedVersion version; /* Version of the head table--currently
58 * 0x00010000 for version 1.0. */
59 FixedVersion fontRevision; /* Set by font manufacturer. */
60 ULONG checkSumAdjustment; /* To compute: set it to 0, sum the
61 * entire font as ULONG, then store
62 * 0xB1B0AFBA - sum. */
63 ULONG magicNumber; /* Set to 0x5F0F3CF5. */
64 USHORT flags; /* Bit 0: Baseline for font at y=0;
65 * Bit 1: Left sidebearing point at x=0;
66 * Bit 2: Instructions may depend on point size;
67 * Bit 3: Force ppem to integer values for all
68 * internal scaler math; may use fractional
69 * ppem sizes if this bit is clear;
70 * Bit 4: Instructions may alter advance width
71 * (the advance widths might not scale linearly);
73 * Bits 5-10: These should be set according to
74 * Apple's specification. However, they are not
75 * implemented in OpenType.
76 * Bit 5: This bit should be set in fonts that are
77 * intended to e laid out vertically, and in
78 * which the glyphs have been drawn such that an
79 * x-coordinate of 0 corresponds to the desired
81 * Bit 6: This bit must be set to zero.
82 * Bit 7: This bit should be set if the font
83 * requires layout for correct linguistic
84 * rendering (e.g. Arabic fonts).
85 * Bit 8: This bit should be set for a GX font
86 * which has one or more metamorphosis effects
87 * designated as happening by default.
88 * Bit 9: This bit should be set if the font
89 * contains any strong right-to-left glyphs.
90 * Bit 10: This bit should be set if the font
91 * contains Indic-style rearrangement effects.
93 * Bit 11: Font data is 'lossless,' as a result
94 * of having been compressed and decompressed
95 * with the Agfa MicroType Express engine.
96 * Bit 12: Font converted (produce compatible metrics)
97 * Bit 13: Font optimized for ClearType™.
98 * Note, fonts that rely on embedded bitmaps (EBDT)
99 * for rendering should not be considered optimized
100 * for ClearType, and therefore should keep this bit
102 * Bit 14: Last Resort font. If set, indicates that
103 * the glyphs encoded in the cmap subtables are simply
104 * generic symbolic representations of code point
105 * ranges and don’t truly represent support for those
106 * code points. If unset, indicates that the glyphs
107 * encoded in the cmap subtables represent proper
108 * support for those code points.
109 * Bit 15: Reserved, set to 0. */
110 USHORT unitsPerEm; /* Valid range is from 16 to 16384. This value
111 * should be a power of 2 for fonts that have
112 * TrueType outlines. */
113 LONGDATETIME created; /* Number of seconds since 12:00 midnight,
114 January 1, 1904. 64-bit integer */
115 LONGDATETIME modified; /* Number of seconds since 12:00 midnight,
116 January 1, 1904. 64-bit integer */
117 SHORT xMin; /* For all glyph bounding boxes. */
118 SHORT yMin; /* For all glyph bounding boxes. */
119 SHORT xMax; /* For all glyph bounding boxes. */
120 SHORT yMax; /* For all glyph bounding boxes. */
121 USHORT macStyle; /* Bit 0: Bold (if set to 1);
122 * Bit 1: Italic (if set to 1)
123 * Bit 2: Underline (if set to 1)
124 * Bit 3: Outline (if set to 1)
125 * Bit 4: Shadow (if set to 1)
126 * Bit 5: Condensed (if set to 1)
127 * Bit 6: Extended (if set to 1)
128 * Bits 7-15: Reserved (set to 0). */
129 USHORT lowestRecPPEM; /* Smallest readable size in pixels. */
130 SHORT fontDirectionHint; /* Deprecated (Set to 2).
131 * 0: Fully mixed directional glyphs;
132 * 1: Only strongly left to right;
133 * 2: Like 1 but also contains neutrals;
134 * -1: Only strongly right to left;
135 * -2: Like -1 but also contains neutrals. */
136 SHORT indexToLocFormat; /* 0 for short offsets, 1 for long. */
137 SHORT glyphDataFormat; /* 0 for current format. */
139 DEFINE_SIZE_STATIC (54);
145 #endif /* HB_OT_HEAD_PRIVATE_HH */