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_MAXP_TABLE_HH
28 #define HB_OT_MAXP_TABLE_HH
29
30 #include "hb-open-type-private.hh"
31 #include "hb-subset-plan.hh"
32
33 namespace OT {
34
35
36 /*
37 * maxp -- Maximum Profile
38 * https://docs.microsoft.com/en-us/typography/opentype/spec/maxp
39 */
40
41 #define HB_OT_TAG_maxp HB_TAG('m','a','x','p')
42
43 struct maxpV1Tail
44 {
45 inline bool sanitize (hb_sanitize_context_t *c) const
46 {
47 TRACE_SANITIZE (this);
48 return_trace (c->check_struct (this));
49 }
50
51 HBUINT16 maxPoints; /* Maximum points in a non-composite glyph. */
52 HBUINT16 maxContours; /* Maximum contours in a non-composite glyph. */
53 HBUINT16 maxCompositePoints; /* Maximum points in a composite glyph. */
54 HBUINT16 maxCompositeContours; /* Maximum contours in a composite glyph. */
55 HBUINT16 maxZones; /* 1 if instructions do not use the twilight zone (Z0),
56 * or 2 if instructions do use Z0; should be set to 2 in
57 * most cases. */
58 HBUINT16 maxTwilightPoints; /* Maximum points used in Z0. */
59 HBUINT16 maxStorage; /* Number of Storage Area locations. */
60 HBUINT16 maxFunctionDefs; /* Number of FDEFs, equal to the highest function number + 1. */
61 HBUINT16 maxInstructionDefs; /* Number of IDEFs. */
62 HBUINT16 maxStackElements; /* Maximum stack depth. (This includes Font and CVT
63 * Programs, as well as the instructions for each glyph.) */
64 HBUINT16 maxSizeOfInstructions; /* Maximum byte count for glyph instructions. */
65 HBUINT16 maxComponentElements; /* Maximum number of components referenced at
66 * "top level" for any composite glyph. */
67 HBUINT16 maxComponentDepth; /* Maximum levels of recursion; 1 for simple components. */
68 public:
69 DEFINE_SIZE_STATIC (26);
70 };
71
72
73 struct maxp
74 {
75 static const hb_tag_t tableTag = HB_OT_TAG_maxp;
76
77 inline unsigned int get_num_glyphs (void) const
78 {
79 return numGlyphs;
80 }
81
82 inline void set_num_glyphs (unsigned int count)
83 {
84 numGlyphs.set (count);
85 }
86
87 inline bool sanitize (hb_sanitize_context_t *c) const
88 {
89 TRACE_SANITIZE (this);
90 if (unlikely (!c->check_struct (this)))
91 return_trace (false);
92
93 if (version.major == 1)
94 {
95 const maxpV1Tail &v1 = StructAfter<maxpV1Tail> (*this);
96 return v1.sanitize (c);
97 }
98 return_trace (likely (version.major == 0 && version.minor == 0x5000u));
99 }
100
101 inline bool subset (hb_subset_plan_t *plan) const
102 {
103 hb_blob_t *maxp_blob = OT::Sanitizer<OT::maxp>().sanitize (hb_face_reference_table (plan->source, HB_OT_TAG_maxp));
104 hb_blob_t *maxp_prime_blob = hb_blob_copy_writable_or_fail (maxp_blob);
105 hb_blob_destroy (maxp_blob);
106
107 if (unlikely (!maxp_prime_blob)) {
108 return false;
109 }
110 OT::maxp *maxp_prime = (OT::maxp *) hb_blob_get_data (maxp_prime_blob, nullptr);
111
112 maxp_prime->set_num_glyphs (plan->glyphs.len);
113 if (plan->drop_hints)
114 drop_hint_fields (plan, maxp_prime);
115
116 bool result = plan->add_table (HB_OT_TAG_maxp, maxp_prime_blob);
117 hb_blob_destroy (maxp_prime_blob);
118 return result;
119 }
120
121 static inline void drop_hint_fields (hb_subset_plan_t *plan, OT::maxp *maxp_prime)
122 {
123 if (maxp_prime->version.major == 1)
124 {
125 maxpV1Tail &v1 = StructAfter<maxpV1Tail> (*maxp_prime);
126 v1.maxZones.set (1);
127 v1.maxTwilightPoints.set (0);
128 v1.maxStorage.set (0);
129 v1.maxFunctionDefs.set (0);
130 v1.maxInstructionDefs.set (0);
131 v1.maxStackElements.set (0);
132 v1.maxSizeOfInstructions.set (0);
133 }
134 }
135
136 protected:
137 FixedVersion<>version; /* Version of the maxp table (0.5 or 1.0),
138 * 0x00005000u or 0x00010000u. */
139 HBUINT16 numGlyphs; /* The number of glyphs in the font. */
140 /*maxpV1Tail v1Tail[VAR]; */
141 public:
142 DEFINE_SIZE_STATIC (6);
143 };
144
145
146 } /* namespace OT */
147
148
149 #endif /* HB_OT_MAXP_TABLE_HH */