2 * Copyright © 2018 Google, Inc.
4 * This is part of HarfBuzz, a text shaping library.
6 * Permission is hereby granted, without written agreement and without
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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.
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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
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24 * Google Author(s): Garret Rieger
27 #ifndef HB_OT_HDMX_TABLE_HH
28 #define HB_OT_HDMX_TABLE_HH
30 #include "hb-open-type.hh"
33 * hdmx -- Horizontal Device Metrics
34 * https://docs.microsoft.com/en-us/typography/opentype/spec/hdmx
36 #define HB_OT_TAG_hdmx HB_TAG('h','d','m','x')
44 static unsigned int get_size (unsigned count)
45 { return hb_ceil_to_4 (min_size + count * HBUINT8::static_size); }
47 template<typename Iterator,
48 hb_requires (hb_is_iterator (Iterator))>
49 bool serialize (hb_serialize_context_t *c, unsigned pixelSize, Iterator it)
51 TRACE_SERIALIZE (this);
53 unsigned length = it.len ();
55 if (unlikely (!c->extend (*this, length))) return_trace (false);
57 this->pixelSize = pixelSize;
60 | hb_reduce (hb_max, 0u);
63 | hb_sink (widthsZ.as_array (length));
68 bool sanitize (hb_sanitize_context_t *c, unsigned sizeDeviceRecord) const
70 TRACE_SANITIZE (this);
71 return_trace (likely (c->check_struct (this) &&
72 c->check_range (this, sizeDeviceRecord)));
75 HBUINT8 pixelSize; /* Pixel size for following widths (as ppem). */
76 HBUINT8 maxWidth; /* Maximum width. */
77 UnsizedArrayOf<HBUINT8> widthsZ; /* Array of widths (numGlyphs is from the 'maxp' table). */
79 DEFINE_SIZE_ARRAY (2, widthsZ);
85 static constexpr hb_tag_t tableTag = HB_OT_TAG_hdmx;
87 unsigned int get_size () const
88 { return min_size + numRecords * sizeDeviceRecord; }
90 const DeviceRecord& operator [] (unsigned int i) const
92 /* XXX Null(DeviceRecord) is NOT safe as it's num-glyphs lengthed.
93 * https://github.com/harfbuzz/harfbuzz/issues/1300 */
94 if (unlikely (i >= numRecords)) return Null (DeviceRecord);
95 return StructAtOffset<DeviceRecord> (&this->firstDeviceRecord, i * sizeDeviceRecord);
98 template<typename Iterator,
99 hb_requires (hb_is_iterator (Iterator))>
100 bool serialize (hb_serialize_context_t *c, unsigned version, Iterator it)
102 TRACE_SERIALIZE (this);
104 if (unlikely (!c->extend_min ((*this)))) return_trace (false);
106 this->version = version;
107 this->numRecords = it.len ();
108 this->sizeDeviceRecord = DeviceRecord::get_size (it ? (*it).second.len () : 0);
111 | hb_apply ([c] (const hb_item_type<Iterator>& _) {
112 c->start_embed<DeviceRecord> ()->serialize (c, _.first, _.second);
116 return_trace (c->successful);
120 bool subset (hb_subset_context_t *c) const
124 hdmx *hdmx_prime = c->serializer->start_embed <hdmx> ();
125 if (unlikely (!hdmx_prime)) return_trace (false);
128 + hb_range ((unsigned) numRecords)
129 | hb_map ([c, this] (unsigned _)
131 const DeviceRecord *device_record =
132 &StructAtOffset<DeviceRecord> (&firstDeviceRecord,
133 _ * sizeDeviceRecord);
135 + hb_range (c->plan->num_output_glyphs ())
136 | hb_map (c->plan->reverse_glyph_map)
137 | hb_map ([=] (hb_codepoint_t _)
139 if (c->plan->is_empty_glyph (_))
140 return Null(HBUINT8);
141 return device_record->widthsZ.as_array (get_num_glyphs ()) [_];
144 return hb_pair ((unsigned) device_record->pixelSize, +row);
148 hdmx_prime->serialize (c->serializer, version, it);
152 unsigned get_num_glyphs () const
154 return sizeDeviceRecord - DeviceRecord::min_size;
157 bool sanitize (hb_sanitize_context_t *c) const
159 TRACE_SANITIZE (this);
160 return_trace (c->check_struct (this) &&
161 !hb_unsigned_mul_overflows (numRecords, sizeDeviceRecord) &&
162 sizeDeviceRecord >= DeviceRecord::min_size &&
163 c->check_range (this, get_size ()));
167 HBUINT16 version; /* Table version number (0) */
168 HBUINT16 numRecords; /* Number of device records. */
169 HBUINT32 sizeDeviceRecord; /* Size of a device record, 32-bit aligned. */
170 DeviceRecord firstDeviceRecord; /* Array of device records. */
178 #endif /* HB_OT_HDMX_TABLE_HH */