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Diffstat (limited to 'gfx/harfbuzz/src/hb-ot-layout-gpos-table.hh')
| -rw-r--r-- | gfx/harfbuzz/src/hb-ot-layout-gpos-table.hh | 1654 |
1 files changed, 1654 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/hb-ot-layout-gpos-table.hh b/gfx/harfbuzz/src/hb-ot-layout-gpos-table.hh new file mode 100644 index 000000000..952fd60fe --- /dev/null +++ b/gfx/harfbuzz/src/hb-ot-layout-gpos-table.hh @@ -0,0 +1,1654 @@ +/* + * Copyright © 2007,2008,2009,2010 Red Hat, Inc. + * Copyright © 2010,2012,2013 Google, Inc. + * + * 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. + * + * Red Hat Author(s): Behdad Esfahbod + * Google Author(s): Behdad Esfahbod + */ + +#ifndef HB_OT_LAYOUT_GPOS_TABLE_HH +#define HB_OT_LAYOUT_GPOS_TABLE_HH + +#include "hb-ot-layout-gsubgpos-private.hh" + + +namespace OT { + + +/* buffer **position** var allocations */ +#define attach_chain() var.i16[0] /* glyph to which this attaches to, relative to current glyphs; negative for going back, positive for forward. */ +#define attach_type() var.u8[2] /* attachment type */ +/* Note! if attach_chain() is zero, the value of attach_type() is irrelevant. */ + +enum attach_type_t { + ATTACH_TYPE_NONE = 0X00, + + /* Each attachment should be either a mark or a cursive; can't be both. */ + ATTACH_TYPE_MARK = 0X01, + ATTACH_TYPE_CURSIVE = 0X02, +}; + + +/* Shared Tables: ValueRecord, Anchor Table, and MarkArray */ + +typedef USHORT Value; + +typedef Value ValueRecord[VAR]; + +struct ValueFormat : USHORT +{ + enum Flags { + xPlacement = 0x0001u, /* Includes horizontal adjustment for placement */ + yPlacement = 0x0002u, /* Includes vertical adjustment for placement */ + xAdvance = 0x0004u, /* Includes horizontal adjustment for advance */ + yAdvance = 0x0008u, /* Includes vertical adjustment for advance */ + xPlaDevice = 0x0010u, /* Includes horizontal Device table for placement */ + yPlaDevice = 0x0020u, /* Includes vertical Device table for placement */ + xAdvDevice = 0x0040u, /* Includes horizontal Device table for advance */ + yAdvDevice = 0x0080u, /* Includes vertical Device table for advance */ + ignored = 0x0F00u, /* Was used in TrueType Open for MM fonts */ + reserved = 0xF000u, /* For future use */ + + devices = 0x00F0u /* Mask for having any Device table */ + }; + +/* All fields are options. Only those available advance the value pointer. */ +#if 0 + SHORT xPlacement; /* Horizontal adjustment for + * placement--in design units */ + SHORT yPlacement; /* Vertical adjustment for + * placement--in design units */ + SHORT xAdvance; /* Horizontal adjustment for + * advance--in design units (only used + * for horizontal writing) */ + SHORT yAdvance; /* Vertical adjustment for advance--in + * design units (only used for vertical + * writing) */ + Offset xPlaDevice; /* Offset to Device table for + * horizontal placement--measured from + * beginning of PosTable (may be NULL) */ + Offset yPlaDevice; /* Offset to Device table for vertical + * placement--measured from beginning + * of PosTable (may be NULL) */ + Offset xAdvDevice; /* Offset to Device table for + * horizontal advance--measured from + * beginning of PosTable (may be NULL) */ + Offset yAdvDevice; /* Offset to Device table for vertical + * advance--measured from beginning of + * PosTable (may be NULL) */ +#endif + + inline unsigned int get_len (void) const + { return _hb_popcount32 ((unsigned int) *this); } + inline unsigned int get_size (void) const + { return get_len () * Value::static_size; } + + void apply_value (hb_apply_context_t *c, + const void *base, + const Value *values, + hb_glyph_position_t &glyph_pos) const + { + unsigned int format = *this; + if (!format) return; + + hb_font_t *font = c->font; + hb_bool_t horizontal = HB_DIRECTION_IS_HORIZONTAL (c->direction); + + if (format & xPlacement) glyph_pos.x_offset += font->em_scale_x (get_short (values++)); + if (format & yPlacement) glyph_pos.y_offset += font->em_scale_y (get_short (values++)); + if (format & xAdvance) { + if (likely (horizontal)) glyph_pos.x_advance += font->em_scale_x (get_short (values)); + values++; + } + /* y_advance values grow downward but font-space grows upward, hence negation */ + if (format & yAdvance) { + if (unlikely (!horizontal)) glyph_pos.y_advance -= font->em_scale_y (get_short (values)); + values++; + } + + if (!has_device ()) return; + + bool use_x_device = font->x_ppem || font->num_coords; + bool use_y_device = font->y_ppem || font->num_coords; + + if (!use_x_device && !use_y_device) return; + + const VariationStore &store = c->var_store; + + /* pixel -> fractional pixel */ + if (format & xPlaDevice) { + if (use_x_device) glyph_pos.x_offset += (base + get_device (values)).get_x_delta (font, store); + values++; + } + if (format & yPlaDevice) { + if (use_y_device) glyph_pos.y_offset += (base + get_device (values)).get_y_delta (font, store); + values++; + } + if (format & xAdvDevice) { + if (horizontal && use_x_device) glyph_pos.x_advance += (base + get_device (values)).get_x_delta (font, store); + values++; + } + if (format & yAdvDevice) { + /* y_advance values grow downward but font-space grows upward, hence negation */ + if (!horizontal && use_y_device) glyph_pos.y_advance -= (base + get_device (values)).get_y_delta (font, store); + values++; + } + } + + private: + inline bool sanitize_value_devices (hb_sanitize_context_t *c, const void *base, const Value *values) const + { + unsigned int format = *this; + + if (format & xPlacement) values++; + if (format & yPlacement) values++; + if (format & xAdvance) values++; + if (format & yAdvance) values++; + + if ((format & xPlaDevice) && !get_device (values++).sanitize (c, base)) return false; + if ((format & yPlaDevice) && !get_device (values++).sanitize (c, base)) return false; + if ((format & xAdvDevice) && !get_device (values++).sanitize (c, base)) return false; + if ((format & yAdvDevice) && !get_device (values++).sanitize (c, base)) return false; + + return true; + } + + static inline OffsetTo<Device>& get_device (Value* value) + { return *CastP<OffsetTo<Device> > (value); } + static inline const OffsetTo<Device>& get_device (const Value* value) + { return *CastP<OffsetTo<Device> > (value); } + + static inline const SHORT& get_short (const Value* value) + { return *CastP<SHORT> (value); } + + public: + + inline bool has_device (void) const { + unsigned int format = *this; + return (format & devices) != 0; + } + + inline bool sanitize_value (hb_sanitize_context_t *c, const void *base, const Value *values) const + { + TRACE_SANITIZE (this); + return_trace (c->check_range (values, get_size ()) && (!has_device () || sanitize_value_devices (c, base, values))); + } + + inline bool sanitize_values (hb_sanitize_context_t *c, const void *base, const Value *values, unsigned int count) const + { + TRACE_SANITIZE (this); + unsigned int len = get_len (); + + if (!c->check_array (values, get_size (), count)) return_trace (false); + + if (!has_device ()) return_trace (true); + + for (unsigned int i = 0; i < count; i++) { + if (!sanitize_value_devices (c, base, values)) + return_trace (false); + values += len; + } + + return_trace (true); + } + + /* Just sanitize referenced Device tables. Doesn't check the values themselves. */ + inline bool sanitize_values_stride_unsafe (hb_sanitize_context_t *c, const void *base, const Value *values, unsigned int count, unsigned int stride) const + { + TRACE_SANITIZE (this); + + if (!has_device ()) return_trace (true); + + for (unsigned int i = 0; i < count; i++) { + if (!sanitize_value_devices (c, base, values)) + return_trace (false); + values += stride; + } + + return_trace (true); + } +}; + + +struct AnchorFormat1 +{ + inline void get_anchor (hb_apply_context_t *c, hb_codepoint_t glyph_id HB_UNUSED, + hb_position_t *x, hb_position_t *y) const + { + hb_font_t *font = c->font; + *x = font->em_scale_x (xCoordinate); + *y = font->em_scale_y (yCoordinate); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + SHORT xCoordinate; /* Horizontal value--in design units */ + SHORT yCoordinate; /* Vertical value--in design units */ + public: + DEFINE_SIZE_STATIC (6); +}; + +struct AnchorFormat2 +{ + inline void get_anchor (hb_apply_context_t *c, hb_codepoint_t glyph_id, + hb_position_t *x, hb_position_t *y) const + { + hb_font_t *font = c->font; + unsigned int x_ppem = font->x_ppem; + unsigned int y_ppem = font->y_ppem; + hb_position_t cx, cy; + hb_bool_t ret; + + ret = (x_ppem || y_ppem) && + font->get_glyph_contour_point_for_origin (glyph_id, anchorPoint, HB_DIRECTION_LTR, &cx, &cy); + *x = ret && x_ppem ? cx : font->em_scale_x (xCoordinate); + *y = ret && y_ppem ? cy : font->em_scale_y (yCoordinate); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this)); + } + + protected: + USHORT format; /* Format identifier--format = 2 */ + SHORT xCoordinate; /* Horizontal value--in design units */ + SHORT yCoordinate; /* Vertical value--in design units */ + USHORT anchorPoint; /* Index to glyph contour point */ + public: + DEFINE_SIZE_STATIC (8); +}; + +struct AnchorFormat3 +{ + inline void get_anchor (hb_apply_context_t *c, hb_codepoint_t glyph_id HB_UNUSED, + hb_position_t *x, hb_position_t *y) const + { + hb_font_t *font = c->font; + *x = font->em_scale_x (xCoordinate); + *y = font->em_scale_y (yCoordinate); + + if (font->x_ppem || font->num_coords) + *x += (this+xDeviceTable).get_x_delta (font, c->var_store); + if (font->y_ppem || font->num_coords) + *y += (this+yDeviceTable).get_y_delta (font, c->var_store); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this) && xDeviceTable.sanitize (c, this) && yDeviceTable.sanitize (c, this)); + } + + protected: + USHORT format; /* Format identifier--format = 3 */ + SHORT xCoordinate; /* Horizontal value--in design units */ + SHORT yCoordinate; /* Vertical value--in design units */ + OffsetTo<Device> + xDeviceTable; /* Offset to Device table for X + * coordinate-- from beginning of + * Anchor table (may be NULL) */ + OffsetTo<Device> + yDeviceTable; /* Offset to Device table for Y + * coordinate-- from beginning of + * Anchor table (may be NULL) */ + public: + DEFINE_SIZE_STATIC (10); +}; + +struct Anchor +{ + inline void get_anchor (hb_apply_context_t *c, hb_codepoint_t glyph_id, + hb_position_t *x, hb_position_t *y) const + { + *x = *y = 0; + switch (u.format) { + case 1: u.format1.get_anchor (c, glyph_id, x, y); return; + case 2: u.format2.get_anchor (c, glyph_id, x, y); return; + case 3: u.format3.get_anchor (c, glyph_id, x, y); return; + default: return; + } + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + if (!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 (true); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + AnchorFormat1 format1; + AnchorFormat2 format2; + AnchorFormat3 format3; + } u; + public: + DEFINE_SIZE_UNION (2, format); +}; + + +struct AnchorMatrix +{ + inline const Anchor& get_anchor (unsigned int row, unsigned int col, unsigned int cols, bool *found) const { + *found = false; + if (unlikely (row >= rows || col >= cols)) return Null(Anchor); + *found = !matrixZ[row * cols + col].is_null (); + return this+matrixZ[row * cols + col]; + } + + inline bool sanitize (hb_sanitize_context_t *c, unsigned int cols) const + { + TRACE_SANITIZE (this); + if (!c->check_struct (this)) return_trace (false); + if (unlikely (_hb_unsigned_int_mul_overflows (rows, cols))) return_trace (false); + unsigned int count = rows * cols; + if (!c->check_array (matrixZ, matrixZ[0].static_size, count)) return_trace (false); + for (unsigned int i = 0; i < count; i++) + if (!matrixZ[i].sanitize (c, this)) return_trace (false); + return_trace (true); + } + + USHORT rows; /* Number of rows */ + protected: + OffsetTo<Anchor> + matrixZ[VAR]; /* Matrix of offsets to Anchor tables-- + * from beginning of AnchorMatrix table */ + public: + DEFINE_SIZE_ARRAY (2, matrixZ); +}; + + +struct MarkRecord +{ + friend struct MarkArray; + + inline bool sanitize (hb_sanitize_context_t *c, const void *base) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this) && markAnchor.sanitize (c, base)); + } + + protected: + USHORT klass; /* Class defined for this mark */ + OffsetTo<Anchor> + markAnchor; /* Offset to Anchor table--from + * beginning of MarkArray table */ + public: + DEFINE_SIZE_STATIC (4); +}; + +struct MarkArray : ArrayOf<MarkRecord> /* Array of MarkRecords--in Coverage order */ +{ + inline bool apply (hb_apply_context_t *c, + unsigned int mark_index, unsigned int glyph_index, + const AnchorMatrix &anchors, unsigned int class_count, + unsigned int glyph_pos) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + const MarkRecord &record = ArrayOf<MarkRecord>::operator[](mark_index); + unsigned int mark_class = record.klass; + + const Anchor& mark_anchor = this + record.markAnchor; + bool found; + const Anchor& glyph_anchor = anchors.get_anchor (glyph_index, mark_class, class_count, &found); + /* If this subtable doesn't have an anchor for this base and this class, + * return false such that the subsequent subtables have a chance at it. */ + if (unlikely (!found)) return_trace (false); + + hb_position_t mark_x, mark_y, base_x, base_y; + + mark_anchor.get_anchor (c, buffer->cur().codepoint, &mark_x, &mark_y); + glyph_anchor.get_anchor (c, buffer->info[glyph_pos].codepoint, &base_x, &base_y); + + hb_glyph_position_t &o = buffer->cur_pos(); + o.x_offset = base_x - mark_x; + o.y_offset = base_y - mark_y; + o.attach_type() = ATTACH_TYPE_MARK; + o.attach_chain() = (int) glyph_pos - (int) buffer->idx; + buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT; + + buffer->idx++; + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (ArrayOf<MarkRecord>::sanitize (c, this)); + } +}; + + +/* Lookups */ + +struct SinglePosFormat1 +{ + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+coverage).add_coverage (c->input); + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + unsigned int index = (this+coverage).get_coverage (buffer->cur().codepoint); + if (likely (index == NOT_COVERED)) return_trace (false); + + valueFormat.apply_value (c, this, values, buffer->cur_pos()); + + buffer->idx++; + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this) && + coverage.sanitize (c, this) && + valueFormat.sanitize_value (c, this, values)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of subtable */ + ValueFormat valueFormat; /* Defines the types of data in the + * ValueRecord */ + ValueRecord values; /* Defines positioning + * value(s)--applied to all glyphs in + * the Coverage table */ + public: + DEFINE_SIZE_ARRAY (6, values); +}; + +struct SinglePosFormat2 +{ + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+coverage).add_coverage (c->input); + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + unsigned int index = (this+coverage).get_coverage (buffer->cur().codepoint); + if (likely (index == NOT_COVERED)) return_trace (false); + + if (likely (index >= valueCount)) return_trace (false); + + valueFormat.apply_value (c, this, + &values[index * valueFormat.get_len ()], + buffer->cur_pos()); + + buffer->idx++; + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this) && + coverage.sanitize (c, this) && + valueFormat.sanitize_values (c, this, values, valueCount)); + } + + protected: + USHORT format; /* Format identifier--format = 2 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of subtable */ + ValueFormat valueFormat; /* Defines the types of data in the + * ValueRecord */ + USHORT valueCount; /* Number of ValueRecords */ + ValueRecord values; /* Array of ValueRecords--positioning + * values applied to glyphs */ + public: + DEFINE_SIZE_ARRAY (8, values); +}; + +struct SinglePos +{ + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + case 2: return_trace (c->dispatch (u.format2)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + SinglePosFormat1 format1; + SinglePosFormat2 format2; + } u; +}; + + +struct PairValueRecord +{ + friend struct PairSet; + + protected: + GlyphID secondGlyph; /* GlyphID of second glyph in the + * pair--first glyph is listed in the + * Coverage table */ + ValueRecord values; /* Positioning data for the first glyph + * followed by for second glyph */ + public: + DEFINE_SIZE_ARRAY (2, values); +}; + +struct PairSet +{ + friend struct PairPosFormat1; + + inline void collect_glyphs (hb_collect_glyphs_context_t *c, + const ValueFormat *valueFormats) const + { + TRACE_COLLECT_GLYPHS (this); + unsigned int len1 = valueFormats[0].get_len (); + unsigned int len2 = valueFormats[1].get_len (); + unsigned int record_size = USHORT::static_size * (1 + len1 + len2); + + const PairValueRecord *record = CastP<PairValueRecord> (arrayZ); + unsigned int count = len; + for (unsigned int i = 0; i < count; i++) + { + c->input->add (record->secondGlyph); + record = &StructAtOffset<PairValueRecord> (record, record_size); + } + } + + inline bool apply (hb_apply_context_t *c, + const ValueFormat *valueFormats, + unsigned int pos) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + unsigned int len1 = valueFormats[0].get_len (); + unsigned int len2 = valueFormats[1].get_len (); + unsigned int record_size = USHORT::static_size * (1 + len1 + len2); + + const PairValueRecord *record_array = CastP<PairValueRecord> (arrayZ); + unsigned int count = len; + + /* Hand-coded bsearch. */ + if (unlikely (!count)) + return_trace (false); + hb_codepoint_t x = buffer->info[pos].codepoint; + int min = 0, max = (int) count - 1; + while (min <= max) + { + int mid = (min + max) / 2; + const PairValueRecord *record = &StructAtOffset<PairValueRecord> (record_array, record_size * mid); + hb_codepoint_t mid_x = record->secondGlyph; + if (x < mid_x) + max = mid - 1; + else if (x > mid_x) + min = mid + 1; + else + { + valueFormats[0].apply_value (c, this, &record->values[0], buffer->cur_pos()); + valueFormats[1].apply_value (c, this, &record->values[len1], buffer->pos[pos]); + if (len2) + pos++; + buffer->idx = pos; + return_trace (true); + } + } + + return_trace (false); + } + + struct sanitize_closure_t { + const void *base; + const ValueFormat *valueFormats; + unsigned int len1; /* valueFormats[0].get_len() */ + unsigned int stride; /* 1 + len1 + len2 */ + }; + + inline bool sanitize (hb_sanitize_context_t *c, const sanitize_closure_t *closure) const + { + TRACE_SANITIZE (this); + if (!(c->check_struct (this) + && c->check_array (arrayZ, USHORT::static_size * closure->stride, len))) return_trace (false); + + unsigned int count = len; + const PairValueRecord *record = CastP<PairValueRecord> (arrayZ); + return_trace (closure->valueFormats[0].sanitize_values_stride_unsafe (c, closure->base, &record->values[0], count, closure->stride) && + closure->valueFormats[1].sanitize_values_stride_unsafe (c, closure->base, &record->values[closure->len1], count, closure->stride)); + } + + protected: + USHORT len; /* Number of PairValueRecords */ + USHORT arrayZ[VAR]; /* Array of PairValueRecords--ordered + * by GlyphID of the second glyph */ + public: + DEFINE_SIZE_ARRAY (2, arrayZ); +}; + +struct PairPosFormat1 +{ + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+coverage).add_coverage (c->input); + unsigned int count = pairSet.len; + for (unsigned int i = 0; i < count; i++) + (this+pairSet[i]).collect_glyphs (c, valueFormat); + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + unsigned int index = (this+coverage).get_coverage (buffer->cur().codepoint); + if (likely (index == NOT_COVERED)) return_trace (false); + + hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; + skippy_iter.reset (buffer->idx, 1); + if (!skippy_iter.next ()) return_trace (false); + + return_trace ((this+pairSet[index]).apply (c, valueFormat, skippy_iter.idx)); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + + if (!c->check_struct (this)) return_trace (false); + + unsigned int len1 = valueFormat[0].get_len (); + unsigned int len2 = valueFormat[1].get_len (); + PairSet::sanitize_closure_t closure = { + this, + valueFormat, + len1, + 1 + len1 + len2 + }; + + return_trace (coverage.sanitize (c, this) && pairSet.sanitize (c, this, &closure)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of subtable */ + ValueFormat valueFormat[2]; /* [0] Defines the types of data in + * ValueRecord1--for the first glyph + * in the pair--may be zero (0) */ + /* [1] Defines the types of data in + * ValueRecord2--for the second glyph + * in the pair--may be zero (0) */ + OffsetArrayOf<PairSet> + pairSet; /* Array of PairSet tables + * ordered by Coverage Index */ + public: + DEFINE_SIZE_ARRAY (10, pairSet); +}; + +struct PairPosFormat2 +{ + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+coverage).add_coverage (c->input); + + unsigned int count1 = class1Count; + const ClassDef &klass1 = this+classDef1; + for (unsigned int i = 0; i < count1; i++) + klass1.add_class (c->input, i); + + unsigned int count2 = class2Count; + const ClassDef &klass2 = this+classDef2; + for (unsigned int i = 0; i < count2; i++) + klass2.add_class (c->input, i); + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + unsigned int index = (this+coverage).get_coverage (buffer->cur().codepoint); + if (likely (index == NOT_COVERED)) return_trace (false); + + hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; + skippy_iter.reset (buffer->idx, 1); + if (!skippy_iter.next ()) return_trace (false); + + unsigned int len1 = valueFormat1.get_len (); + unsigned int len2 = valueFormat2.get_len (); + unsigned int record_len = len1 + len2; + + unsigned int klass1 = (this+classDef1).get_class (buffer->cur().codepoint); + unsigned int klass2 = (this+classDef2).get_class (buffer->info[skippy_iter.idx].codepoint); + if (unlikely (klass1 >= class1Count || klass2 >= class2Count)) return_trace (false); + + const Value *v = &values[record_len * (klass1 * class2Count + klass2)]; + valueFormat1.apply_value (c, this, v, buffer->cur_pos()); + valueFormat2.apply_value (c, this, v + len1, buffer->pos[skippy_iter.idx]); + + buffer->idx = skippy_iter.idx; + if (len2) + buffer->idx++; + + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + if (!(c->check_struct (this) + && coverage.sanitize (c, this) + && classDef1.sanitize (c, this) + && classDef2.sanitize (c, this))) return_trace (false); + + unsigned int len1 = valueFormat1.get_len (); + unsigned int len2 = valueFormat2.get_len (); + unsigned int stride = len1 + len2; + unsigned int record_size = valueFormat1.get_size () + valueFormat2.get_size (); + unsigned int count = (unsigned int) class1Count * (unsigned int) class2Count; + return_trace (c->check_array (values, record_size, count) && + valueFormat1.sanitize_values_stride_unsafe (c, this, &values[0], count, stride) && + valueFormat2.sanitize_values_stride_unsafe (c, this, &values[len1], count, stride)); + } + + protected: + USHORT format; /* Format identifier--format = 2 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of subtable */ + ValueFormat valueFormat1; /* ValueRecord definition--for the + * first glyph of the pair--may be zero + * (0) */ + ValueFormat valueFormat2; /* ValueRecord definition--for the + * second glyph of the pair--may be + * zero (0) */ + OffsetTo<ClassDef> + classDef1; /* Offset to ClassDef table--from + * beginning of PairPos subtable--for + * the first glyph of the pair */ + OffsetTo<ClassDef> + classDef2; /* Offset to ClassDef table--from + * beginning of PairPos subtable--for + * the second glyph of the pair */ + USHORT class1Count; /* Number of classes in ClassDef1 + * table--includes Class0 */ + USHORT class2Count; /* Number of classes in ClassDef2 + * table--includes Class0 */ + ValueRecord values; /* Matrix of value pairs: + * class1-major, class2-minor, + * Each entry has value1 and value2 */ + public: + DEFINE_SIZE_ARRAY (16, values); +}; + +struct PairPos +{ + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + case 2: return_trace (c->dispatch (u.format2)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + PairPosFormat1 format1; + PairPosFormat2 format2; + } u; +}; + + +struct EntryExitRecord +{ + friend struct CursivePosFormat1; + + inline bool sanitize (hb_sanitize_context_t *c, const void *base) const + { + TRACE_SANITIZE (this); + return_trace (entryAnchor.sanitize (c, base) && exitAnchor.sanitize (c, base)); + } + + protected: + OffsetTo<Anchor> + entryAnchor; /* Offset to EntryAnchor table--from + * beginning of CursivePos + * subtable--may be NULL */ + OffsetTo<Anchor> + exitAnchor; /* Offset to ExitAnchor table--from + * beginning of CursivePos + * subtable--may be NULL */ + public: + DEFINE_SIZE_STATIC (4); +}; + +static void +reverse_cursive_minor_offset (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction, unsigned int new_parent); + +struct CursivePosFormat1 +{ + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+coverage).add_coverage (c->input); + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + + const EntryExitRecord &this_record = entryExitRecord[(this+coverage).get_coverage (buffer->cur().codepoint)]; + if (!this_record.exitAnchor) return_trace (false); + + hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; + skippy_iter.reset (buffer->idx, 1); + if (!skippy_iter.next ()) return_trace (false); + + const EntryExitRecord &next_record = entryExitRecord[(this+coverage).get_coverage (buffer->info[skippy_iter.idx].codepoint)]; + if (!next_record.entryAnchor) return_trace (false); + + unsigned int i = buffer->idx; + unsigned int j = skippy_iter.idx; + + hb_position_t entry_x, entry_y, exit_x, exit_y; + (this+this_record.exitAnchor).get_anchor (c, buffer->info[i].codepoint, &exit_x, &exit_y); + (this+next_record.entryAnchor).get_anchor (c, buffer->info[j].codepoint, &entry_x, &entry_y); + + hb_glyph_position_t *pos = buffer->pos; + + hb_position_t d; + /* Main-direction adjustment */ + switch (c->direction) { + case HB_DIRECTION_LTR: + pos[i].x_advance = exit_x + pos[i].x_offset; + + d = entry_x + pos[j].x_offset; + pos[j].x_advance -= d; + pos[j].x_offset -= d; + break; + case HB_DIRECTION_RTL: + d = exit_x + pos[i].x_offset; + pos[i].x_advance -= d; + pos[i].x_offset -= d; + + pos[j].x_advance = entry_x + pos[j].x_offset; + break; + case HB_DIRECTION_TTB: + pos[i].y_advance = exit_y + pos[i].y_offset; + + d = entry_y + pos[j].y_offset; + pos[j].y_advance -= d; + pos[j].y_offset -= d; + break; + case HB_DIRECTION_BTT: + d = exit_y + pos[i].y_offset; + pos[i].y_advance -= d; + pos[i].y_offset -= d; + + pos[j].y_advance = entry_y; + break; + case HB_DIRECTION_INVALID: + default: + break; + } + + /* Cross-direction adjustment */ + + /* We attach child to parent (think graph theory and rooted trees whereas + * the root stays on baseline and each node aligns itself against its + * parent. + * + * Optimize things for the case of RightToLeft, as that's most common in + * Arabinc. */ + unsigned int child = i; + unsigned int parent = j; + hb_position_t x_offset = entry_x - exit_x; + hb_position_t y_offset = entry_y - exit_y; + if (!(c->lookup_props & LookupFlag::RightToLeft)) + { + unsigned int k = child; + child = parent; + parent = k; + x_offset = -x_offset; + y_offset = -y_offset; + } + + /* If child was already connected to someone else, walk through its old + * chain and reverse the link direction, such that the whole tree of its + * previous connection now attaches to new parent. Watch out for case + * where new parent is on the path from old chain... + */ + reverse_cursive_minor_offset (pos, child, c->direction, parent); + + pos[child].attach_type() = ATTACH_TYPE_CURSIVE; + pos[child].attach_chain() = (int) parent - (int) child; + buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT; + if (likely (HB_DIRECTION_IS_HORIZONTAL (c->direction))) + pos[child].y_offset = y_offset; + else + pos[child].x_offset = x_offset; + + buffer->idx = j; + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (coverage.sanitize (c, this) && entryExitRecord.sanitize (c, this)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of subtable */ + ArrayOf<EntryExitRecord> + entryExitRecord; /* Array of EntryExit records--in + * Coverage Index order */ + public: + DEFINE_SIZE_ARRAY (6, entryExitRecord); +}; + +struct CursivePos +{ + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + CursivePosFormat1 format1; + } u; +}; + + +typedef AnchorMatrix BaseArray; /* base-major-- + * in order of BaseCoverage Index--, + * mark-minor-- + * ordered by class--zero-based. */ + +struct MarkBasePosFormat1 +{ + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+markCoverage).add_coverage (c->input); + (this+baseCoverage).add_coverage (c->input); + } + + inline const Coverage &get_coverage (void) const + { + return this+markCoverage; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + unsigned int mark_index = (this+markCoverage).get_coverage (buffer->cur().codepoint); + if (likely (mark_index == NOT_COVERED)) return_trace (false); + + /* Now we search backwards for a non-mark glyph */ + hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; + skippy_iter.reset (buffer->idx, 1); + skippy_iter.set_lookup_props (LookupFlag::IgnoreMarks); + do { + if (!skippy_iter.prev ()) return_trace (false); + /* We only want to attach to the first of a MultipleSubst sequence. Reject others. */ + if (0 == _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx])) break; + skippy_iter.reject (); + } while (1); + + /* Checking that matched glyph is actually a base glyph by GDEF is too strong; disabled */ + //if (!_hb_glyph_info_is_base_glyph (&buffer->info[skippy_iter.idx])) { return_trace (false); } + + unsigned int base_index = (this+baseCoverage).get_coverage (buffer->info[skippy_iter.idx].codepoint); + if (base_index == NOT_COVERED) return_trace (false); + + return_trace ((this+markArray).apply (c, mark_index, base_index, this+baseArray, classCount, skippy_iter.idx)); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this) && + markCoverage.sanitize (c, this) && + baseCoverage.sanitize (c, this) && + markArray.sanitize (c, this) && + baseArray.sanitize (c, this, (unsigned int) classCount)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + markCoverage; /* Offset to MarkCoverage table--from + * beginning of MarkBasePos subtable */ + OffsetTo<Coverage> + baseCoverage; /* Offset to BaseCoverage table--from + * beginning of MarkBasePos subtable */ + USHORT classCount; /* Number of classes defined for marks */ + OffsetTo<MarkArray> + markArray; /* Offset to MarkArray table--from + * beginning of MarkBasePos subtable */ + OffsetTo<BaseArray> + baseArray; /* Offset to BaseArray table--from + * beginning of MarkBasePos subtable */ + public: + DEFINE_SIZE_STATIC (12); +}; + +struct MarkBasePos +{ + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + MarkBasePosFormat1 format1; + } u; +}; + + +typedef AnchorMatrix LigatureAttach; /* component-major-- + * in order of writing direction--, + * mark-minor-- + * ordered by class--zero-based. */ + +typedef OffsetListOf<LigatureAttach> LigatureArray; + /* Array of LigatureAttach + * tables ordered by + * LigatureCoverage Index */ + +struct MarkLigPosFormat1 +{ + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+markCoverage).add_coverage (c->input); + (this+ligatureCoverage).add_coverage (c->input); + } + + inline const Coverage &get_coverage (void) const + { + return this+markCoverage; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + unsigned int mark_index = (this+markCoverage).get_coverage (buffer->cur().codepoint); + if (likely (mark_index == NOT_COVERED)) return_trace (false); + + /* Now we search backwards for a non-mark glyph */ + hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; + skippy_iter.reset (buffer->idx, 1); + skippy_iter.set_lookup_props (LookupFlag::IgnoreMarks); + if (!skippy_iter.prev ()) return_trace (false); + + /* Checking that matched glyph is actually a ligature by GDEF is too strong; disabled */ + //if (!_hb_glyph_info_is_ligature (&buffer->info[skippy_iter.idx])) { return_trace (false); } + + unsigned int j = skippy_iter.idx; + unsigned int lig_index = (this+ligatureCoverage).get_coverage (buffer->info[j].codepoint); + if (lig_index == NOT_COVERED) return_trace (false); + + const LigatureArray& lig_array = this+ligatureArray; + const LigatureAttach& lig_attach = lig_array[lig_index]; + + /* Find component to attach to */ + unsigned int comp_count = lig_attach.rows; + if (unlikely (!comp_count)) return_trace (false); + + /* We must now check whether the ligature ID of the current mark glyph + * is identical to the ligature ID of the found ligature. If yes, we + * can directly use the component index. If not, we attach the mark + * glyph to the last component of the ligature. */ + unsigned int comp_index; + unsigned int lig_id = _hb_glyph_info_get_lig_id (&buffer->info[j]); + unsigned int mark_id = _hb_glyph_info_get_lig_id (&buffer->cur()); + unsigned int mark_comp = _hb_glyph_info_get_lig_comp (&buffer->cur()); + if (lig_id && lig_id == mark_id && mark_comp > 0) + comp_index = MIN (comp_count, _hb_glyph_info_get_lig_comp (&buffer->cur())) - 1; + else + comp_index = comp_count - 1; + + return_trace ((this+markArray).apply (c, mark_index, comp_index, lig_attach, classCount, j)); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this) && + markCoverage.sanitize (c, this) && + ligatureCoverage.sanitize (c, this) && + markArray.sanitize (c, this) && + ligatureArray.sanitize (c, this, (unsigned int) classCount)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + markCoverage; /* Offset to Mark Coverage table--from + * beginning of MarkLigPos subtable */ + OffsetTo<Coverage> + ligatureCoverage; /* Offset to Ligature Coverage + * table--from beginning of MarkLigPos + * subtable */ + USHORT classCount; /* Number of defined mark classes */ + OffsetTo<MarkArray> + markArray; /* Offset to MarkArray table--from + * beginning of MarkLigPos subtable */ + OffsetTo<LigatureArray> + ligatureArray; /* Offset to LigatureArray table--from + * beginning of MarkLigPos subtable */ + public: + DEFINE_SIZE_STATIC (12); +}; + +struct MarkLigPos +{ + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + MarkLigPosFormat1 format1; + } u; +}; + + +typedef AnchorMatrix Mark2Array; /* mark2-major-- + * in order of Mark2Coverage Index--, + * mark1-minor-- + * ordered by class--zero-based. */ + +struct MarkMarkPosFormat1 +{ + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+mark1Coverage).add_coverage (c->input); + (this+mark2Coverage).add_coverage (c->input); + } + + inline const Coverage &get_coverage (void) const + { + return this+mark1Coverage; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_buffer_t *buffer = c->buffer; + unsigned int mark1_index = (this+mark1Coverage).get_coverage (buffer->cur().codepoint); + if (likely (mark1_index == NOT_COVERED)) return_trace (false); + + /* now we search backwards for a suitable mark glyph until a non-mark glyph */ + hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; + skippy_iter.reset (buffer->idx, 1); + skippy_iter.set_lookup_props (c->lookup_props & ~LookupFlag::IgnoreFlags); + if (!skippy_iter.prev ()) return_trace (false); + + if (!_hb_glyph_info_is_mark (&buffer->info[skippy_iter.idx])) { return_trace (false); } + + unsigned int j = skippy_iter.idx; + + unsigned int id1 = _hb_glyph_info_get_lig_id (&buffer->cur()); + unsigned int id2 = _hb_glyph_info_get_lig_id (&buffer->info[j]); + unsigned int comp1 = _hb_glyph_info_get_lig_comp (&buffer->cur()); + unsigned int comp2 = _hb_glyph_info_get_lig_comp (&buffer->info[j]); + + if (likely (id1 == id2)) { + if (id1 == 0) /* Marks belonging to the same base. */ + goto good; + else if (comp1 == comp2) /* Marks belonging to the same ligature component. */ + goto good; + } else { + /* If ligature ids don't match, it may be the case that one of the marks + * itself is a ligature. In which case match. */ + if ((id1 > 0 && !comp1) || (id2 > 0 && !comp2)) + goto good; + } + + /* Didn't match. */ + return_trace (false); + + good: + unsigned int mark2_index = (this+mark2Coverage).get_coverage (buffer->info[j].codepoint); + if (mark2_index == NOT_COVERED) return_trace (false); + + return_trace ((this+mark1Array).apply (c, mark1_index, mark2_index, this+mark2Array, classCount, j)); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this) && + mark1Coverage.sanitize (c, this) && + mark2Coverage.sanitize (c, this) && + mark1Array.sanitize (c, this) && + mark2Array.sanitize (c, this, (unsigned int) classCount)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + mark1Coverage; /* Offset to Combining Mark1 Coverage + * table--from beginning of MarkMarkPos + * subtable */ + OffsetTo<Coverage> + mark2Coverage; /* Offset to Combining Mark2 Coverage + * table--from beginning of MarkMarkPos + * subtable */ + USHORT classCount; /* Number of defined mark classes */ + OffsetTo<MarkArray> + mark1Array; /* Offset to Mark1Array table--from + * beginning of MarkMarkPos subtable */ + OffsetTo<Mark2Array> + mark2Array; /* Offset to Mark2Array table--from + * beginning of MarkMarkPos subtable */ + public: + DEFINE_SIZE_STATIC (12); +}; + +struct MarkMarkPos +{ + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + MarkMarkPosFormat1 format1; + } u; +}; + + +struct ContextPos : Context {}; + +struct ChainContextPos : ChainContext {}; + +struct ExtensionPos : Extension<ExtensionPos> +{ + typedef struct PosLookupSubTable LookupSubTable; +}; + + + +/* + * PosLookup + */ + + +struct PosLookupSubTable +{ + friend struct PosLookup; + + enum Type { + Single = 1, + Pair = 2, + Cursive = 3, + MarkBase = 4, + MarkLig = 5, + MarkMark = 6, + Context = 7, + ChainContext = 8, + Extension = 9 + }; + + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c, unsigned int lookup_type) const + { + TRACE_DISPATCH (this, lookup_type); + if (unlikely (!c->may_dispatch (this, &u.sub_format))) return_trace (c->no_dispatch_return_value ()); + switch (lookup_type) { + case Single: return_trace (u.single.dispatch (c)); + case Pair: return_trace (u.pair.dispatch (c)); + case Cursive: return_trace (u.cursive.dispatch (c)); + case MarkBase: return_trace (u.markBase.dispatch (c)); + case MarkLig: return_trace (u.markLig.dispatch (c)); + case MarkMark: return_trace (u.markMark.dispatch (c)); + case Context: return_trace (u.context.dispatch (c)); + case ChainContext: return_trace (u.chainContext.dispatch (c)); + case Extension: return_trace (u.extension.dispatch (c)); + default: return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT sub_format; + SinglePos single; + PairPos pair; + CursivePos cursive; + MarkBasePos markBase; + MarkLigPos markLig; + MarkMarkPos markMark; + ContextPos context; + ChainContextPos chainContext; + ExtensionPos extension; + } u; + public: + DEFINE_SIZE_UNION (2, sub_format); +}; + + +struct PosLookup : Lookup +{ + inline const PosLookupSubTable& get_subtable (unsigned int i) const + { return Lookup::get_subtable<PosLookupSubTable> (i); } + + inline bool is_reverse (void) const + { + return false; + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + return_trace (dispatch (c)); + } + + inline hb_collect_glyphs_context_t::return_t collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + return_trace (dispatch (c)); + } + + template <typename set_t> + inline void add_coverage (set_t *glyphs) const + { + hb_add_coverage_context_t<set_t> c (glyphs); + dispatch (&c); + } + + static bool apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index); + + template <typename context_t> + static inline typename context_t::return_t dispatch_recurse_func (context_t *c, unsigned int lookup_index); + + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { return Lookup::dispatch<PosLookupSubTable> (c); } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + if (unlikely (!Lookup::sanitize (c))) return_trace (false); + return_trace (dispatch (c)); + } +}; + +typedef OffsetListOf<PosLookup> PosLookupList; + +/* + * GPOS -- The Glyph Positioning Table + */ + +struct GPOS : GSUBGPOS +{ + static const hb_tag_t tableTag = HB_OT_TAG_GPOS; + + inline const PosLookup& get_lookup (unsigned int i) const + { return CastR<PosLookup> (GSUBGPOS::get_lookup (i)); } + + static inline void position_start (hb_font_t *font, hb_buffer_t *buffer); + static inline void position_finish_advances (hb_font_t *font, hb_buffer_t *buffer); + static inline void position_finish_offsets (hb_font_t *font, hb_buffer_t *buffer); + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + if (unlikely (!GSUBGPOS::sanitize (c))) return_trace (false); + const OffsetTo<PosLookupList> &list = CastR<OffsetTo<PosLookupList> > (lookupList); + return_trace (list.sanitize (c, this)); + } +}; + + +static void +reverse_cursive_minor_offset (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction, unsigned int new_parent) +{ + int chain = pos[i].attach_chain(), type = pos[i].attach_type(); + if (likely (!chain || 0 == (type & ATTACH_TYPE_CURSIVE))) + return; + + pos[i].attach_chain() = 0; + + unsigned int j = (int) i + chain; + + /* Stop if we see new parent in the chain. */ + if (j == new_parent) + return; + + reverse_cursive_minor_offset (pos, j, direction, new_parent); + + if (HB_DIRECTION_IS_HORIZONTAL (direction)) + pos[j].y_offset = -pos[i].y_offset; + else + pos[j].x_offset = -pos[i].x_offset; + + pos[j].attach_chain() = -chain; + pos[j].attach_type() = type; +} +static void +propagate_attachment_offsets (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction) +{ + /* Adjusts offsets of attached glyphs (both cursive and mark) to accumulate + * offset of glyph they are attached to. */ + int chain = pos[i].attach_chain(), type = pos[i].attach_type(); + if (likely (!chain)) + return; + + unsigned int j = (int) i + chain; + + pos[i].attach_chain() = 0; + + propagate_attachment_offsets (pos, j, direction); + + assert (!!(type & ATTACH_TYPE_MARK) ^ !!(type & ATTACH_TYPE_CURSIVE)); + + if (type & ATTACH_TYPE_CURSIVE) + { + if (HB_DIRECTION_IS_HORIZONTAL (direction)) + pos[i].y_offset += pos[j].y_offset; + else + pos[i].x_offset += pos[j].x_offset; + } + else /*if (type & ATTACH_TYPE_MARK)*/ + { + pos[i].x_offset += pos[j].x_offset; + pos[i].y_offset += pos[j].y_offset; + + assert (j < i); + if (HB_DIRECTION_IS_FORWARD (direction)) + for (unsigned int k = j; k < i; k++) { + pos[i].x_offset -= pos[k].x_advance; + pos[i].y_offset -= pos[k].y_advance; + } + else + for (unsigned int k = j + 1; k < i + 1; k++) { + pos[i].x_offset += pos[k].x_advance; + pos[i].y_offset += pos[k].y_advance; + } + } +} + +void +GPOS::position_start (hb_font_t *font HB_UNUSED, hb_buffer_t *buffer) +{ + unsigned int count = buffer->len; + for (unsigned int i = 0; i < count; i++) + buffer->pos[i].attach_chain() = buffer->pos[i].attach_type() = 0; +} + +void +GPOS::position_finish_advances (hb_font_t *font HB_UNUSED, hb_buffer_t *buffer) +{ + //_hb_buffer_assert_gsubgpos_vars (buffer); +} + +void +GPOS::position_finish_offsets (hb_font_t *font HB_UNUSED, hb_buffer_t *buffer) +{ + _hb_buffer_assert_gsubgpos_vars (buffer); + + unsigned int len; + hb_glyph_position_t *pos = hb_buffer_get_glyph_positions (buffer, &len); + hb_direction_t direction = buffer->props.direction; + + /* Handle attachments */ + if (buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT) + for (unsigned int i = 0; i < len; i++) + propagate_attachment_offsets (pos, i, direction); +} + + +/* Out-of-class implementation for methods recursing */ + +template <typename context_t> +/*static*/ inline typename context_t::return_t PosLookup::dispatch_recurse_func (context_t *c, unsigned int lookup_index) +{ + const GPOS &gpos = *(hb_ot_layout_from_face (c->face)->gpos); + const PosLookup &l = gpos.get_lookup (lookup_index); + return l.dispatch (c); +} + +/*static*/ inline bool PosLookup::apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index) +{ + const GPOS &gpos = *(hb_ot_layout_from_face (c->face)->gpos); + const PosLookup &l = gpos.get_lookup (lookup_index); + unsigned int saved_lookup_props = c->lookup_props; + unsigned int saved_lookup_index = c->lookup_index; + c->set_lookup_index (lookup_index); + c->set_lookup_props (l.get_props ()); + bool ret = l.dispatch (c); + c->set_lookup_index (saved_lookup_index); + c->set_lookup_props (saved_lookup_props); + return ret; +} + + +#undef attach_chain +#undef attach_type + + +} /* namespace OT */ + + +#endif /* HB_OT_LAYOUT_GPOS_TABLE_HH */ |