Edit
kc3-lang/harfbuzz/src/hb-ot-layout-base-table.hh
Ebrahim Byagowi
- src/hb-ot-layout-base-table.hh
-
/* * Copyright © 2016 Elie Roux <elie.roux@telecom-bretagne.eu> * Copyright © 2018 Google, Inc. * Copyright © 2018-2019 Ebrahim Byagowi * * This is part of HarfBuzz, a text shaping library. * * Permission is hereby granted, without written agreement and without * license or royalty fees, to use, copy, modify, and distribute this * software and its documentation for any purpose, provided that the * above copyright notice and the following two paragraphs appear in * all copies of this software. * * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH * DAMAGE. * * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. * * Google Author(s): Behdad Esfahbod */ #ifndef HB_OT_LAYOUT_BASE_TABLE_HH #define HB_OT_LAYOUT_BASE_TABLE_HH #include "hb-open-type.hh" #include "hb-ot-layout-common.hh" namespace OT { /* * BASE -- Baseline * https://docs.microsoft.com/en-us/typography/opentype/spec/base */ struct BaseCoordFormat1 { hb_position_t get_coord () const { return coordinate; } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this))); } protected: HBUINT16 format; /* Format identifier--format = 1 */ FWORD coordinate; /* X or Y value, in design units */ public: DEFINE_SIZE_STATIC (4); }; struct BaseCoordFormat2 { hb_position_t get_coord () const { /* TODO */ return coordinate; } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (c->check_struct (this)); } protected: HBUINT16 format; /* Format identifier--format = 2 */ FWORD coordinate; /* X or Y value, in design units */ HBGlyphID referenceGlyph; /* Glyph ID of control glyph */ HBUINT16 coordPoint; /* Index of contour point on the * reference glyph */ public: DEFINE_SIZE_STATIC (8); }; struct BaseCoordFormat3 { hb_position_t get_coord (hb_font_t *font, const VariationStore &var_store, hb_direction_t direction) const { const Device &device = this+deviceTable; return coordinate + (HB_DIRECTION_IS_VERTICAL (direction) ? device.get_y_delta (font, var_store) : device.get_x_delta (font, var_store)); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && deviceTable.sanitize (c, this))); } protected: HBUINT16 format; /* Format identifier--format = 3 */ FWORD coordinate; /* X or Y value, in design units */ OffsetTo<Device> deviceTable; /* Offset to Device table for X or * Y value, from beginning of * BaseCoord table (may be NULL). */ public: DEFINE_SIZE_STATIC (6); }; struct BaseCoord { bool has_data () const { return u.format; } hb_position_t get_coord (hb_font_t *font, const VariationStore &var_store, hb_direction_t direction) const { switch (u.format) { case 1: return u.format1.get_coord (); case 2: return u.format2.get_coord (); case 3: return u.format3.get_coord (font, var_store, direction); default:return 0; } } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); if (unlikely (!u.format.sanitize (c))) return_trace (false); switch (u.format) { case 1: return_trace (u.format1.sanitize (c)); case 2: return_trace (u.format2.sanitize (c)); case 3: return_trace (u.format3.sanitize (c)); default:return_trace (false); } } protected: union { HBUINT16 format; BaseCoordFormat1 format1; BaseCoordFormat2 format2; BaseCoordFormat3 format3; } u; public: DEFINE_SIZE_UNION (2, format); }; struct FeatMinMaxRecord { int cmp (hb_tag_t key) const { return tag.cmp (key); } bool has_data () const { return tag; } void get_min_max (const BaseCoord **min, const BaseCoord **max) const { if (likely (min)) *min = &(this+minCoord); if (likely (max)) *max = &(this+maxCoord); } bool sanitize (hb_sanitize_context_t *c, const void *base) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && minCoord.sanitize (c, this) && maxCoord.sanitize (c, this))); } protected: Tag tag; /* 4-byte feature identification tag--must * match feature tag in FeatureList */ OffsetTo<BaseCoord> minCoord; /* Offset to BaseCoord table that defines * the minimum extent value, from beginning * of MinMax table (may be NULL) */ OffsetTo<BaseCoord> maxCoord; /* Offset to BaseCoord table that defines * the maximum extent value, from beginning * of MinMax table (may be NULL) */ public: DEFINE_SIZE_STATIC (8); }; struct MinMax { void get_min_max (hb_tag_t feature_tag, const BaseCoord **min, const BaseCoord **max) const { const FeatMinMaxRecord &minMaxCoord = featMinMaxRecords.bsearch (feature_tag); if (minMaxCoord.has_data ()) minMaxCoord.get_min_max (min, max); else { if (likely (min)) *min = &(this+minCoord); if (likely (max)) *max = &(this+maxCoord); } } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && minCoord.sanitize (c, this) && maxCoord.sanitize (c, this) && featMinMaxRecords.sanitize (c, this))); } protected: OffsetTo<BaseCoord> minCoord; /* Offset to BaseCoord table that defines * minimum extent value, from the beginning * of MinMax table (may be NULL) */ OffsetTo<BaseCoord> maxCoord; /* Offset to BaseCoord table that defines * maximum extent value, from the beginning * of MinMax table (may be NULL) */ SortedArrayOf<FeatMinMaxRecord> featMinMaxRecords; /* Array of FeatMinMaxRecords, in alphabetical * order by featureTableTag */ public: DEFINE_SIZE_ARRAY (6, featMinMaxRecords); }; struct BaseValues { const BaseCoord &get_base_coord (int baseline_tag_index) const { if (baseline_tag_index == -1) baseline_tag_index = defaultIndex; return this+baseCoords[baseline_tag_index]; } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && baseCoords.sanitize (c, this))); } protected: Index defaultIndex; /* Index number of default baseline for this * script — equals index position of baseline tag * in baselineTags array of the BaseTagList */ OffsetArrayOf<BaseCoord> baseCoords; /* Number of BaseCoord tables defined — should equal * baseTagCount in the BaseTagList * * Array of offsets to BaseCoord tables, from beginning of * BaseValues table — order matches baselineTags array in * the BaseTagList */ public: DEFINE_SIZE_ARRAY (4, baseCoords); }; struct BaseLangSysRecord { int cmp (hb_tag_t key) const { return baseLangSysTag.cmp (key); } bool has_data () const { return baseLangSysTag; } const MinMax &get_min_max () const { return this+minMax; } bool sanitize (hb_sanitize_context_t *c, const void *base) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && minMax.sanitize (c, this))); } protected: Tag baseLangSysTag; /* 4-byte language system identification tag */ OffsetTo<MinMax> minMax; /* Offset to MinMax table, from beginning * of BaseScript table */ public: DEFINE_SIZE_STATIC (6); }; struct BaseScript { const MinMax &get_min_max (hb_tag_t language_tag) const { const BaseLangSysRecord& record = baseLangSysRecords.bsearch (language_tag); return record.has_data () ? record.get_min_max () : this+defaultMinMax; } const BaseCoord &get_base_coord (int baseline_tag_index) const { return (this+baseValues).get_base_coord (baseline_tag_index); } bool has_data () const { return baseValues; } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && baseValues.sanitize (c, this) && defaultMinMax.sanitize (c, this) && baseLangSysRecords.sanitize (c, this))); } protected: OffsetTo<BaseValues> baseValues; /* Offset to BaseValues table, from beginning * of BaseScript table (may be NULL) */ OffsetTo<MinMax> defaultMinMax; /* Offset to MinMax table, from beginning of * BaseScript table (may be NULL) */ SortedArrayOf<BaseLangSysRecord> baseLangSysRecords; /* Number of BaseLangSysRecords * defined — may be zero (0) */ public: DEFINE_SIZE_ARRAY (6, baseLangSysRecords); }; struct BaseScriptList; struct BaseScriptRecord { int cmp (hb_tag_t key) const { return baseScriptTag.cmp (key); } bool has_data () const { return baseScriptTag; } const BaseScript &get_base_script (const BaseScriptList *list) const { return list+baseScript; } bool sanitize (hb_sanitize_context_t *c, const void *base) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && baseScript.sanitize (c, base))); } protected: Tag baseScriptTag; /* 4-byte script identification tag */ OffsetTo<BaseScript> baseScript; /* Offset to BaseScript table, from beginning * of BaseScriptList */ public: DEFINE_SIZE_STATIC (6); }; struct BaseScriptList { const BaseScript &get_base_script (hb_tag_t script) const { const BaseScriptRecord *record = &baseScriptRecords.bsearch (script); if (!record->has_data ()) record = &baseScriptRecords.bsearch (HB_TAG ('D','F','L','T')); return record->has_data () ? record->get_base_script (this) : Null (BaseScript); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (c->check_struct (this) && baseScriptRecords.sanitize (c, this)); } protected: SortedArrayOf<BaseScriptRecord> baseScriptRecords; public: DEFINE_SIZE_ARRAY (2, baseScriptRecords); }; struct Axis { bool get_baseline (hb_tag_t baseline_tag, hb_tag_t script_tag, hb_tag_t language_tag, const BaseCoord **coord) const { const BaseScript &base_script = (this+baseScriptList).get_base_script (script_tag); if (!base_script.has_data ()) return false; if (likely (coord)) { unsigned int tag_index = 0; (this+baseTagList).bfind (baseline_tag, &tag_index); *coord = &base_script.get_base_coord (tag_index); } return true; } bool get_min_max (hb_tag_t script_tag, hb_tag_t language_tag, hb_tag_t feature_tag, const BaseCoord **min_coord, const BaseCoord **max_coord) const { const BaseScript &base_script = (this+baseScriptList).get_base_script (script_tag); if (!base_script.has_data ()) return false; base_script.get_min_max (language_tag).get_min_max (feature_tag, min_coord, max_coord); return true; } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && (this+baseTagList).sanitize (c) && (this+baseScriptList).sanitize (c))); } protected: OffsetTo<SortedArrayOf<Tag>> baseTagList; /* Offset to BaseTagList table, from beginning * of Axis table (may be NULL) * Array of 4-byte baseline identification tags — must * be in alphabetical order */ OffsetTo<BaseScriptList> baseScriptList; /* Offset to BaseScriptList table, from beginning * of Axis table * Array of BaseScriptRecords, in alphabetical order * by baseScriptTag */ public: DEFINE_SIZE_STATIC (4); }; struct BASE { static constexpr hb_tag_t tableTag = HB_OT_TAG_BASE; const Axis &get_axis (hb_direction_t direction) const { return HB_DIRECTION_IS_VERTICAL (direction) ? this+vAxis : this+hAxis; } const VariationStore &get_var_store () const { return version.to_int () < 0x00010001u ? Null (VariationStore) : this+varStore; } bool get_baseline (hb_font_t *font, hb_tag_t baseline_tag, hb_direction_t direction, hb_tag_t script_tag, hb_tag_t language_tag, hb_position_t *base) const { const BaseCoord *base_coord = nullptr; if (unlikely (!get_axis (direction).get_baseline (baseline_tag, script_tag, language_tag, &base_coord) || !base_coord || !base_coord->has_data ())) return false; if (likely (base)) *base = base_coord->get_coord (font, get_var_store (), direction); return true; } /* TODO: Expose this separately sometime? */ bool get_min_max (hb_font_t *font, hb_direction_t direction, hb_tag_t script_tag, hb_tag_t language_tag, hb_tag_t feature_tag, hb_position_t *min, hb_position_t *max) { const BaseCoord *min_coord, *max_coord; if (!get_axis (direction).get_min_max (script_tag, language_tag, feature_tag, &min_coord, &max_coord)) return false; const VariationStore &var_store = get_var_store (); if (likely (min && min_coord)) *min = min_coord->get_coord (font, var_store, direction); if (likely (max && max_coord)) *max = max_coord->get_coord (font, var_store, direction); return true; } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (likely (c->check_struct (this) && likely (version.major == 1) && hAxis.sanitize (c, this) && vAxis.sanitize (c, this) && (version.to_int () < 0x00010001u || varStore.sanitize (c, this)))); } protected: FixedVersion<>version; /* Version of the BASE table */ OffsetTo<Axis>hAxis; /* Offset to horizontal Axis table, from beginning * of BASE table (may be NULL) */ OffsetTo<Axis>vAxis; /* Offset to vertical Axis table, from beginning * of BASE table (may be NULL) */ LOffsetTo<VariationStore> varStore; /* Offset to the table of Item Variation * Store--from beginning of BASE * header (may be NULL). Introduced * in version 0x00010001. */ public: DEFINE_SIZE_MIN (8); }; } /* namespace OT */ #endif /* HB_OT_LAYOUT_BASE_TABLE_HH */