2 * Copyright © 2017 Google, 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 * Google Author(s): Behdad Esfahbod
27 #ifndef HB_OT_VAR_FVAR_TABLE_HH
28 #define HB_OT_VAR_FVAR_TABLE_HH
30 #include "hb-open-type-private.hh"
33 * fvar -- Font Variations
34 * https://docs.microsoft.com/en-us/typography/opentype/spec/fvar
37 #define HB_OT_TAG_fvar HB_TAG('f','v','a','r')
45 inline bool sanitize (hb_sanitize_context_t *c, unsigned int axis_count) const
47 TRACE_SANITIZE (this);
48 return_trace (c->check_struct (this) &&
49 c->check_array (coordinates, coordinates[0].static_size, axis_count));
53 NameID subfamilyNameID;/* The name ID for entries in the 'name' table
54 * that provide subfamily names for this instance. */
55 HBUINT16 reserved; /* Reserved for future use — set to 0. */
56 Fixed coordinates[VAR];/* The coordinates array for this instance. */
57 //NameID postScriptNameIDX;/*Optional. The name ID for entries in the 'name'
58 // * table that provide PostScript names for this
62 DEFINE_SIZE_ARRAY (4, coordinates);
67 inline bool sanitize (hb_sanitize_context_t *c) const
69 TRACE_SANITIZE (this);
70 return_trace (c->check_struct (this));
74 Tag axisTag; /* Tag identifying the design variation for the axis. */
75 Fixed minValue; /* The minimum coordinate value for the axis. */
76 Fixed defaultValue; /* The default coordinate value for the axis. */
77 Fixed maxValue; /* The maximum coordinate value for the axis. */
78 HBUINT16 reserved; /* Reserved for future use — set to 0. */
79 NameID axisNameID; /* The name ID for entries in the 'name' table that
80 * provide a display name for this axis. */
83 DEFINE_SIZE_STATIC (20);
88 static const hb_tag_t tableTag = HB_OT_TAG_fvar;
90 inline bool sanitize (hb_sanitize_context_t *c) const
92 TRACE_SANITIZE (this);
93 return_trace (version.sanitize (c) &&
94 likely (version.major == 1) &&
95 c->check_struct (this) &&
96 instanceSize >= axisCount * 4 + 4 &&
97 axisSize <= 1024 && /* Arbitrary, just to simplify overflow checks. */
98 instanceSize <= 1024 && /* Arbitrary, just to simplify overflow checks. */
99 c->check_range (this, things) &&
100 c->check_range (&StructAtOffset<char> (this, things),
101 axisCount * axisSize + instanceCount * instanceSize));
104 inline unsigned int get_axis_count (void) const
105 { return axisCount; }
107 inline bool get_axis (unsigned int index, hb_ot_var_axis_t *info) const
109 if (unlikely (index >= axisCount))
114 const AxisRecord &axis = get_axes ()[index];
115 info->tag = axis.axisTag;
116 info->name_id = axis.axisNameID;
117 info->default_value = axis.defaultValue / 65536.;
118 /* Ensure order, to simplify client math. */
119 info->min_value = MIN<float> (info->default_value, axis.minValue / 65536.);
120 info->max_value = MAX<float> (info->default_value, axis.maxValue / 65536.);
126 inline unsigned int get_axis_infos (unsigned int start_offset,
127 unsigned int *axes_count /* IN/OUT */,
128 hb_ot_var_axis_t *axes_array /* OUT */) const
132 unsigned int count = axisCount;
133 start_offset = MIN (start_offset, count);
135 count -= start_offset;
136 axes_array += start_offset;
138 count = MIN (count, *axes_count);
141 for (unsigned int i = 0; i < count; i++)
142 get_axis (start_offset + i, axes_array + i);
147 inline bool find_axis (hb_tag_t tag, unsigned int *index, hb_ot_var_axis_t *info) const
149 const AxisRecord *axes = get_axes ();
150 unsigned int count = get_axis_count ();
151 for (unsigned int i = 0; i < count; i++)
152 if (axes[i].axisTag == tag)
156 return get_axis (i, info);
159 *index = HB_OT_VAR_NO_AXIS_INDEX;
163 inline int normalize_axis_value (unsigned int axis_index, float v) const
165 hb_ot_var_axis_t axis;
166 if (!get_axis (axis_index, &axis))
169 v = MAX (MIN (v, axis.max_value), axis.min_value); /* Clamp. */
171 if (v == axis.default_value)
173 else if (v < axis.default_value)
174 v = (v - axis.default_value) / (axis.default_value - axis.min_value);
176 v = (v - axis.default_value) / (axis.max_value - axis.default_value);
177 return (int) (v * 16384. + (v >= 0. ? .5 : -.5));
181 inline const AxisRecord * get_axes (void) const
182 { return &StructAtOffset<AxisRecord> (this, things); }
184 inline const InstanceRecord * get_instances (void) const
185 { return &StructAtOffset<InstanceRecord> (get_axes () + axisCount, 0); }
188 FixedVersion<>version; /* Version of the fvar table
189 * initially set to 0x00010000u */
190 Offset16 things; /* Offset in bytes from the beginning of the table
191 * to the start of the AxisRecord array. */
192 HBUINT16 reserved; /* This field is permanently reserved. Set to 2. */
193 HBUINT16 axisCount; /* The number of variation axes in the font (the
194 * number of records in the axes array). */
195 HBUINT16 axisSize; /* The size in bytes of each VariationAxisRecord —
196 * set to 20 (0x0014) for this version. */
197 HBUINT16 instanceCount; /* The number of named instances defined in the font
198 * (the number of records in the instances array). */
199 HBUINT16 instanceSize; /* The size in bytes of each InstanceRecord — set
200 * to either axisCount * sizeof(Fixed) + 4, or to
201 * axisCount * sizeof(Fixed) + 6. */
204 DEFINE_SIZE_STATIC (16);
210 #endif /* HB_OT_VAR_FVAR_TABLE_HH */