michael@0: /*
michael@0:  * Copyright © 2007,2008,2009,2010  Red Hat, Inc.
michael@0:  * Copyright © 2010,2012,2013  Google, Inc.
michael@0:  *
michael@0:  *  This is part of HarfBuzz, a text shaping library.
michael@0:  *
michael@0:  * Permission is hereby granted, without written agreement and without
michael@0:  * license or royalty fees, to use, copy, modify, and distribute this
michael@0:  * software and its documentation for any purpose, provided that the
michael@0:  * above copyright notice and the following two paragraphs appear in
michael@0:  * all copies of this software.
michael@0:  *
michael@0:  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
michael@0:  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
michael@0:  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
michael@0:  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
michael@0:  * DAMAGE.
michael@0:  *
michael@0:  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
michael@0:  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
michael@0:  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
michael@0:  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
michael@0:  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
michael@0:  *
michael@0:  * Red Hat Author(s): Behdad Esfahbod
michael@0:  * Google Author(s): Behdad Esfahbod
michael@0:  */
michael@0: 
michael@0: #ifndef HB_OT_LAYOUT_GPOS_TABLE_HH
michael@0: #define HB_OT_LAYOUT_GPOS_TABLE_HH
michael@0: 
michael@0: #include "hb-ot-layout-gsubgpos-private.hh"
michael@0: 
michael@0: 
michael@0: namespace OT {
michael@0: 
michael@0: 
michael@0: /* buffer **position** var allocations */
michael@0: #define attach_lookback() var.u16[0] /* number of glyphs to go back to attach this glyph to its base */
michael@0: #define cursive_chain() var.i16[1] /* character to which this connects, may be positive or negative */
michael@0: 
michael@0: 
michael@0: /* Shared Tables: ValueRecord, Anchor Table, and MarkArray */
michael@0: 
michael@0: typedef USHORT Value;
michael@0: 
michael@0: typedef Value ValueRecord[VAR];
michael@0: 
michael@0: struct ValueFormat : USHORT
michael@0: {
michael@0:   enum Flags {
michael@0:     xPlacement	= 0x0001,	/* Includes horizontal adjustment for placement */
michael@0:     yPlacement	= 0x0002,	/* Includes vertical adjustment for placement */
michael@0:     xAdvance	= 0x0004,	/* Includes horizontal adjustment for advance */
michael@0:     yAdvance	= 0x0008,	/* Includes vertical adjustment for advance */
michael@0:     xPlaDevice	= 0x0010,	/* Includes horizontal Device table for placement */
michael@0:     yPlaDevice	= 0x0020,	/* Includes vertical Device table for placement */
michael@0:     xAdvDevice	= 0x0040,	/* Includes horizontal Device table for advance */
michael@0:     yAdvDevice	= 0x0080,	/* Includes vertical Device table for advance */
michael@0:     ignored	= 0x0F00,	/* Was used in TrueType Open for MM fonts */
michael@0:     reserved	= 0xF000,	/* For future use */
michael@0: 
michael@0:     devices	= 0x00F0	/* Mask for having any Device table */
michael@0:   };
michael@0: 
michael@0: /* All fields are options.  Only those available advance the value pointer. */
michael@0: #if 0
michael@0:   SHORT		xPlacement;		/* Horizontal adjustment for
michael@0: 					 * placement--in design units */
michael@0:   SHORT		yPlacement;		/* Vertical adjustment for
michael@0: 					 * placement--in design units */
michael@0:   SHORT		xAdvance;		/* Horizontal adjustment for
michael@0: 					 * advance--in design units (only used
michael@0: 					 * for horizontal writing) */
michael@0:   SHORT		yAdvance;		/* Vertical adjustment for advance--in
michael@0: 					 * design units (only used for vertical
michael@0: 					 * writing) */
michael@0:   Offset	xPlaDevice;		/* Offset to Device table for
michael@0: 					 * horizontal placement--measured from
michael@0: 					 * beginning of PosTable (may be NULL) */
michael@0:   Offset	yPlaDevice;		/* Offset to Device table for vertical
michael@0: 					 * placement--measured from beginning
michael@0: 					 * of PosTable (may be NULL) */
michael@0:   Offset	xAdvDevice;		/* Offset to Device table for
michael@0: 					 * horizontal advance--measured from
michael@0: 					 * beginning of PosTable (may be NULL) */
michael@0:   Offset	yAdvDevice;		/* Offset to Device table for vertical
michael@0: 					 * advance--measured from beginning of
michael@0: 					 * PosTable (may be NULL) */
michael@0: #endif
michael@0: 
michael@0:   inline unsigned int get_len (void) const
michael@0:   { return _hb_popcount32 ((unsigned int) *this); }
michael@0:   inline unsigned int get_size (void) const
michael@0:   { return get_len () * Value::static_size; }
michael@0: 
michael@0:   void apply_value (hb_font_t            *font,
michael@0: 		    hb_direction_t        direction,
michael@0: 		    const void           *base,
michael@0: 		    const Value          *values,
michael@0: 		    hb_glyph_position_t  &glyph_pos) const
michael@0:   {
michael@0:     unsigned int x_ppem, y_ppem;
michael@0:     unsigned int format = *this;
michael@0:     hb_bool_t horizontal = HB_DIRECTION_IS_HORIZONTAL (direction);
michael@0: 
michael@0:     if (!format) return;
michael@0: 
michael@0:     if (format & xPlacement) glyph_pos.x_offset  += font->em_scale_x (get_short (values++));
michael@0:     if (format & yPlacement) glyph_pos.y_offset  += font->em_scale_y (get_short (values++));
michael@0:     if (format & xAdvance) {
michael@0:       if (likely (horizontal)) glyph_pos.x_advance += font->em_scale_x (get_short (values));
michael@0:       values++;
michael@0:     }
michael@0:     /* y_advance values grow downward but font-space grows upward, hence negation */
michael@0:     if (format & yAdvance) {
michael@0:       if (unlikely (!horizontal)) glyph_pos.y_advance -= font->em_scale_y (get_short (values));
michael@0:       values++;
michael@0:     }
michael@0: 
michael@0:     if (!has_device ()) return;
michael@0: 
michael@0:     x_ppem = font->x_ppem;
michael@0:     y_ppem = font->y_ppem;
michael@0: 
michael@0:     if (!x_ppem && !y_ppem) return;
michael@0: 
michael@0:     /* pixel -> fractional pixel */
michael@0:     if (format & xPlaDevice) {
michael@0:       if (x_ppem) glyph_pos.x_offset  += (base + get_device (values)).get_x_delta (font);
michael@0:       values++;
michael@0:     }
michael@0:     if (format & yPlaDevice) {
michael@0:       if (y_ppem) glyph_pos.y_offset  += (base + get_device (values)).get_y_delta (font);
michael@0:       values++;
michael@0:     }
michael@0:     if (format & xAdvDevice) {
michael@0:       if (horizontal && x_ppem) glyph_pos.x_advance += (base + get_device (values)).get_x_delta (font);
michael@0:       values++;
michael@0:     }
michael@0:     if (format & yAdvDevice) {
michael@0:       /* y_advance values grow downward but font-space grows upward, hence negation */
michael@0:       if (!horizontal && y_ppem) glyph_pos.y_advance -= (base + get_device (values)).get_y_delta (font);
michael@0:       values++;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   private:
michael@0:   inline bool sanitize_value_devices (hb_sanitize_context_t *c, void *base, Value *values) {
michael@0:     unsigned int format = *this;
michael@0: 
michael@0:     if (format & xPlacement) values++;
michael@0:     if (format & yPlacement) values++;
michael@0:     if (format & xAdvance)   values++;
michael@0:     if (format & yAdvance)   values++;
michael@0: 
michael@0:     if ((format & xPlaDevice) && !get_device (values++).sanitize (c, base)) return false;
michael@0:     if ((format & yPlaDevice) && !get_device (values++).sanitize (c, base)) return false;
michael@0:     if ((format & xAdvDevice) && !get_device (values++).sanitize (c, base)) return false;
michael@0:     if ((format & yAdvDevice) && !get_device (values++).sanitize (c, base)) return false;
michael@0: 
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   static inline OffsetTo<Device>& get_device (Value* value)
michael@0:   { return *CastP<OffsetTo<Device> > (value); }
michael@0:   static inline const OffsetTo<Device>& get_device (const Value* value)
michael@0:   { return *CastP<OffsetTo<Device> > (value); }
michael@0: 
michael@0:   static inline const SHORT& get_short (const Value* value)
michael@0:   { return *CastP<SHORT> (value); }
michael@0: 
michael@0:   public:
michael@0: 
michael@0:   inline bool has_device (void) const {
michael@0:     unsigned int format = *this;
michael@0:     return (format & devices) != 0;
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize_value (hb_sanitize_context_t *c, void *base, Value *values) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_range (values, get_size ()) && (!has_device () || sanitize_value_devices (c, base, values)));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize_values (hb_sanitize_context_t *c, void *base, Value *values, unsigned int count) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     unsigned int len = get_len ();
michael@0: 
michael@0:     if (!c->check_array (values, get_size (), count)) return TRACE_RETURN (false);
michael@0: 
michael@0:     if (!has_device ()) return TRACE_RETURN (true);
michael@0: 
michael@0:     for (unsigned int i = 0; i < count; i++) {
michael@0:       if (!sanitize_value_devices (c, base, values))
michael@0:         return TRACE_RETURN (false);
michael@0:       values += len;
michael@0:     }
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   /* Just sanitize referenced Device tables.  Doesn't check the values themselves. */
michael@0:   inline bool sanitize_values_stride_unsafe (hb_sanitize_context_t *c, void *base, Value *values, unsigned int count, unsigned int stride) {
michael@0:     TRACE_SANITIZE (this);
michael@0: 
michael@0:     if (!has_device ()) return TRACE_RETURN (true);
michael@0: 
michael@0:     for (unsigned int i = 0; i < count; i++) {
michael@0:       if (!sanitize_value_devices (c, base, values))
michael@0:         return TRACE_RETURN (false);
michael@0:       values += stride;
michael@0:     }
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: };
michael@0: 
michael@0: 
michael@0: struct AnchorFormat1
michael@0: {
michael@0:   inline void get_anchor (hb_font_t *font, hb_codepoint_t glyph_id HB_UNUSED,
michael@0: 			  hb_position_t *x, hb_position_t *y) const
michael@0:   {
michael@0:       *x = font->em_scale_x (xCoordinate);
michael@0:       *y = font->em_scale_y (yCoordinate);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   SHORT		xCoordinate;		/* Horizontal value--in design units */
michael@0:   SHORT		yCoordinate;		/* Vertical value--in design units */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (6);
michael@0: };
michael@0: 
michael@0: struct AnchorFormat2
michael@0: {
michael@0:   inline void get_anchor (hb_font_t *font, hb_codepoint_t glyph_id,
michael@0: 			  hb_position_t *x, hb_position_t *y) const
michael@0:   {
michael@0:       unsigned int x_ppem = font->x_ppem;
michael@0:       unsigned int y_ppem = font->y_ppem;
michael@0:       hb_position_t cx, cy;
michael@0:       hb_bool_t ret;
michael@0: 
michael@0:       ret = (x_ppem || y_ppem) &&
michael@0:              font->get_glyph_contour_point_for_origin (glyph_id, anchorPoint, HB_DIRECTION_LTR, &cx, &cy);
michael@0:       *x = ret && x_ppem ? cx : font->em_scale_x (xCoordinate);
michael@0:       *y = ret && y_ppem ? cy : font->em_scale_y (yCoordinate);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 2 */
michael@0:   SHORT		xCoordinate;		/* Horizontal value--in design units */
michael@0:   SHORT		yCoordinate;		/* Vertical value--in design units */
michael@0:   USHORT	anchorPoint;		/* Index to glyph contour point */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (8);
michael@0: };
michael@0: 
michael@0: struct AnchorFormat3
michael@0: {
michael@0:   inline void get_anchor (hb_font_t *font, hb_codepoint_t glyph_id HB_UNUSED,
michael@0: 			  hb_position_t *x, hb_position_t *y) const
michael@0:   {
michael@0:       *x = font->em_scale_x (xCoordinate);
michael@0:       *y = font->em_scale_y (yCoordinate);
michael@0: 
michael@0:       if (font->x_ppem)
michael@0: 	*x += (this+xDeviceTable).get_x_delta (font);
michael@0:       if (font->y_ppem)
michael@0: 	*y += (this+yDeviceTable).get_x_delta (font);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this) && xDeviceTable.sanitize (c, this) && yDeviceTable.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 3 */
michael@0:   SHORT		xCoordinate;		/* Horizontal value--in design units */
michael@0:   SHORT		yCoordinate;		/* Vertical value--in design units */
michael@0:   OffsetTo<Device>
michael@0: 		xDeviceTable;		/* Offset to Device table for X
michael@0: 					 * coordinate-- from beginning of
michael@0: 					 * Anchor table (may be NULL) */
michael@0:   OffsetTo<Device>
michael@0: 		yDeviceTable;		/* Offset to Device table for Y
michael@0: 					 * coordinate-- from beginning of
michael@0: 					 * Anchor table (may be NULL) */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (10);
michael@0: };
michael@0: 
michael@0: struct Anchor
michael@0: {
michael@0:   inline void get_anchor (hb_font_t *font, hb_codepoint_t glyph_id,
michael@0: 			  hb_position_t *x, hb_position_t *y) const
michael@0:   {
michael@0:     *x = *y = 0;
michael@0:     switch (u.format) {
michael@0:     case 1: u.format1.get_anchor (font, glyph_id, x, y); return;
michael@0:     case 2: u.format2.get_anchor (font, glyph_id, x, y); return;
michael@0:     case 3: u.format3.get_anchor (font, glyph_id, x, y); return;
michael@0:     default:						 return;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     case 2: return TRACE_RETURN (u.format2.sanitize (c));
michael@0:     case 3: return TRACE_RETURN (u.format3.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   AnchorFormat1		format1;
michael@0:   AnchorFormat2		format2;
michael@0:   AnchorFormat3		format3;
michael@0:   } u;
michael@0:   public:
michael@0:   DEFINE_SIZE_UNION (2, format);
michael@0: };
michael@0: 
michael@0: 
michael@0: struct AnchorMatrix
michael@0: {
michael@0:   inline const Anchor& get_anchor (unsigned int row, unsigned int col, unsigned int cols, bool *found) const {
michael@0:     *found = false;
michael@0:     if (unlikely (row >= rows || col >= cols)) return Null(Anchor);
michael@0:     *found = !matrix[row * cols + col].is_null ();
michael@0:     return this+matrix[row * cols + col];
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, unsigned int cols) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!c->check_struct (this)) return TRACE_RETURN (false);
michael@0:     if (unlikely (rows > 0 && cols >= ((unsigned int) -1) / rows)) return TRACE_RETURN (false);
michael@0:     unsigned int count = rows * cols;
michael@0:     if (!c->check_array (matrix, matrix[0].static_size, count)) return TRACE_RETURN (false);
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (!matrix[i].sanitize (c, this)) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   USHORT	rows;			/* Number of rows */
michael@0:   protected:
michael@0:   OffsetTo<Anchor>
michael@0: 		matrix[VAR];		/* Matrix of offsets to Anchor tables--
michael@0: 					 * from beginning of AnchorMatrix table */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (2, matrix);
michael@0: };
michael@0: 
michael@0: 
michael@0: struct MarkRecord
michael@0: {
michael@0:   friend struct MarkArray;
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, void *base) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this) && markAnchor.sanitize (c, base));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	klass;			/* Class defined for this mark */
michael@0:   OffsetTo<Anchor>
michael@0: 		markAnchor;		/* Offset to Anchor table--from
michael@0: 					 * beginning of MarkArray table */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (4);
michael@0: };
michael@0: 
michael@0: struct MarkArray : ArrayOf<MarkRecord>	/* Array of MarkRecords--in Coverage order */
michael@0: {
michael@0:   inline bool apply (hb_apply_context_t *c,
michael@0: 		     unsigned int mark_index, unsigned int glyph_index,
michael@0: 		     const AnchorMatrix &anchors, unsigned int class_count,
michael@0: 		     unsigned int glyph_pos) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     const MarkRecord &record = ArrayOf<MarkRecord>::operator[](mark_index);
michael@0:     unsigned int mark_class = record.klass;
michael@0: 
michael@0:     const Anchor& mark_anchor = this + record.markAnchor;
michael@0:     bool found;
michael@0:     const Anchor& glyph_anchor = anchors.get_anchor (glyph_index, mark_class, class_count, &found);
michael@0:     /* If this subtable doesn't have an anchor for this base and this class,
michael@0:      * return false such that the subsequent subtables have a chance at it. */
michael@0:     if (unlikely (!found)) return TRACE_RETURN (false);
michael@0: 
michael@0:     hb_position_t mark_x, mark_y, base_x, base_y;
michael@0: 
michael@0:     mark_anchor.get_anchor (c->font, buffer->cur().codepoint, &mark_x, &mark_y);
michael@0:     glyph_anchor.get_anchor (c->font, buffer->info[glyph_pos].codepoint, &base_x, &base_y);
michael@0: 
michael@0:     hb_glyph_position_t &o = buffer->cur_pos();
michael@0:     o.x_offset = base_x - mark_x;
michael@0:     o.y_offset = base_y - mark_y;
michael@0:     o.attach_lookback() = buffer->idx - glyph_pos;
michael@0: 
michael@0:     buffer->idx++;
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (ArrayOf<MarkRecord>::sanitize (c, this));
michael@0:   }
michael@0: };
michael@0: 
michael@0: 
michael@0: /* Lookups */
michael@0: 
michael@0: struct SinglePosFormat1
michael@0: {
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage).add_coverage (c->input);
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     unsigned int index = (this+coverage).get_coverage  (buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     valueFormat.apply_value (c->font, c->direction, this,
michael@0: 			     values, buffer->cur_pos());
michael@0: 
michael@0:     buffer->idx++;
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this) && coverage.sanitize (c, this) && valueFormat.sanitize_value (c, this, values));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of subtable */
michael@0:   ValueFormat	valueFormat;		/* Defines the types of data in the
michael@0: 					 * ValueRecord */
michael@0:   ValueRecord	values;			/* Defines positioning
michael@0: 					 * value(s)--applied to all glyphs in
michael@0: 					 * the Coverage table */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (6, values);
michael@0: };
michael@0: 
michael@0: struct SinglePosFormat2
michael@0: {
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage).add_coverage (c->input);
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     unsigned int index = (this+coverage).get_coverage  (buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     if (likely (index >= valueCount)) return TRACE_RETURN (false);
michael@0: 
michael@0:     valueFormat.apply_value (c->font, c->direction, this,
michael@0: 			     &values[index * valueFormat.get_len ()],
michael@0: 			     buffer->cur_pos());
michael@0: 
michael@0:     buffer->idx++;
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this) && coverage.sanitize (c, this) && valueFormat.sanitize_values (c, this, values, valueCount));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 2 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of subtable */
michael@0:   ValueFormat	valueFormat;		/* Defines the types of data in the
michael@0: 					 * ValueRecord */
michael@0:   USHORT	valueCount;		/* Number of ValueRecords */
michael@0:   ValueRecord	values;			/* Array of ValueRecords--positioning
michael@0: 					 * values applied to glyphs */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (8, values);
michael@0: };
michael@0: 
michael@0: struct SinglePos
michael@0: {
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
michael@0:     case 2: return TRACE_RETURN (c->dispatch (u.format2));
michael@0:     default:return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     case 2: return TRACE_RETURN (u.format2.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   SinglePosFormat1	format1;
michael@0:   SinglePosFormat2	format2;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: struct PairValueRecord
michael@0: {
michael@0:   friend struct PairSet;
michael@0: 
michael@0:   protected:
michael@0:   GlyphID	secondGlyph;		/* GlyphID of second glyph in the
michael@0: 					 * pair--first glyph is listed in the
michael@0: 					 * Coverage table */
michael@0:   ValueRecord	values;			/* Positioning data for the first glyph
michael@0: 					 * followed by for second glyph */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (2, values);
michael@0: };
michael@0: 
michael@0: struct PairSet
michael@0: {
michael@0:   friend struct PairPosFormat1;
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c,
michael@0: 			      const ValueFormat *valueFormats) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     unsigned int len1 = valueFormats[0].get_len ();
michael@0:     unsigned int len2 = valueFormats[1].get_len ();
michael@0:     unsigned int record_size = USHORT::static_size * (1 + len1 + len2);
michael@0: 
michael@0:     const PairValueRecord *record = CastP<PairValueRecord> (array);
michael@0:     unsigned int count = len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:     {
michael@0:       c->input->add (record->secondGlyph);
michael@0:       record = &StructAtOffset<PairValueRecord> (record, record_size);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c,
michael@0: 		     const ValueFormat *valueFormats,
michael@0: 		     unsigned int pos) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     unsigned int len1 = valueFormats[0].get_len ();
michael@0:     unsigned int len2 = valueFormats[1].get_len ();
michael@0:     unsigned int record_size = USHORT::static_size * (1 + len1 + len2);
michael@0: 
michael@0:     const PairValueRecord *record = CastP<PairValueRecord> (array);
michael@0:     unsigned int count = len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:     {
michael@0:       /* TODO bsearch */
michael@0:       if (buffer->info[pos].codepoint == record->secondGlyph)
michael@0:       {
michael@0: 	valueFormats[0].apply_value (c->font, c->direction, this,
michael@0: 				     &record->values[0], buffer->cur_pos());
michael@0: 	valueFormats[1].apply_value (c->font, c->direction, this,
michael@0: 				     &record->values[len1], buffer->pos[pos]);
michael@0: 	if (len2)
michael@0: 	  pos++;
michael@0: 	buffer->idx = pos;
michael@0: 	return TRACE_RETURN (true);
michael@0:       }
michael@0:       record = &StructAtOffset<PairValueRecord> (record, record_size);
michael@0:     }
michael@0: 
michael@0:     return TRACE_RETURN (false);
michael@0:   }
michael@0: 
michael@0:   struct sanitize_closure_t {
michael@0:     void *base;
michael@0:     ValueFormat *valueFormats;
michael@0:     unsigned int len1; /* valueFormats[0].get_len() */
michael@0:     unsigned int stride; /* 1 + len1 + len2 */
michael@0:   };
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, const sanitize_closure_t *closure) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!(c->check_struct (this)
michael@0:        && c->check_array (array, USHORT::static_size * closure->stride, len))) return TRACE_RETURN (false);
michael@0: 
michael@0:     unsigned int count = len;
michael@0:     PairValueRecord *record = CastP<PairValueRecord> (array);
michael@0:     return TRACE_RETURN (closure->valueFormats[0].sanitize_values_stride_unsafe (c, closure->base, &record->values[0], count, closure->stride)
michael@0: 		      && closure->valueFormats[1].sanitize_values_stride_unsafe (c, closure->base, &record->values[closure->len1], count, closure->stride));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	len;			/* Number of PairValueRecords */
michael@0:   USHORT	array[VAR];		/* Array of PairValueRecords--ordered
michael@0: 					 * by GlyphID of the second glyph */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (2, array);
michael@0: };
michael@0: 
michael@0: struct PairPosFormat1
michael@0: {
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage).add_coverage (c->input);
michael@0:     unsigned int count = pairSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       (this+pairSet[i]).collect_glyphs (c, &valueFormat1);
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     hb_apply_context_t::skipping_forward_iterator_t skippy_iter (c, buffer->idx, 1);
michael@0:     if (skippy_iter.has_no_chance ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     unsigned int index = (this+coverage).get_coverage  (buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     if (!skippy_iter.next ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     return TRACE_RETURN ((this+pairSet[index]).apply (c, &valueFormat1, skippy_iter.idx));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0: 
michael@0:     unsigned int len1 = valueFormat1.get_len ();
michael@0:     unsigned int len2 = valueFormat2.get_len ();
michael@0:     PairSet::sanitize_closure_t closure = {
michael@0:       this,
michael@0:       &valueFormat1,
michael@0:       len1,
michael@0:       1 + len1 + len2
michael@0:     };
michael@0: 
michael@0:     return TRACE_RETURN (c->check_struct (this) && coverage.sanitize (c, this) && pairSet.sanitize (c, this, &closure));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of subtable */
michael@0:   ValueFormat	valueFormat1;		/* Defines the types of data in
michael@0: 					 * ValueRecord1--for the first glyph
michael@0: 					 * in the pair--may be zero (0) */
michael@0:   ValueFormat	valueFormat2;		/* Defines the types of data in
michael@0: 					 * ValueRecord2--for the second glyph
michael@0: 					 * in the pair--may be zero (0) */
michael@0:   OffsetArrayOf<PairSet>
michael@0: 		pairSet;		/* Array of PairSet tables
michael@0: 					 * ordered by Coverage Index */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (10, pairSet);
michael@0: };
michael@0: 
michael@0: struct PairPosFormat2
michael@0: {
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     /* (this+coverage).add_coverage (c->input); // Don't need this. */
michael@0: 
michael@0:     unsigned int count1 = class1Count;
michael@0:     const ClassDef &klass1 = this+classDef1;
michael@0:     for (unsigned int i = 0; i < count1; i++)
michael@0:       klass1.add_class (c->input, i);
michael@0: 
michael@0:     unsigned int count2 = class2Count;
michael@0:     const ClassDef &klass2 = this+classDef2;
michael@0:     for (unsigned int i = 0; i < count2; i++)
michael@0:       klass2.add_class (c->input, i);
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     hb_apply_context_t::skipping_forward_iterator_t skippy_iter (c, buffer->idx, 1);
michael@0:     if (skippy_iter.has_no_chance ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     unsigned int index = (this+coverage).get_coverage  (buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     if (!skippy_iter.next ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     unsigned int len1 = valueFormat1.get_len ();
michael@0:     unsigned int len2 = valueFormat2.get_len ();
michael@0:     unsigned int record_len = len1 + len2;
michael@0: 
michael@0:     unsigned int klass1 = (this+classDef1).get_class (buffer->cur().codepoint);
michael@0:     unsigned int klass2 = (this+classDef2).get_class (buffer->info[skippy_iter.idx].codepoint);
michael@0:     if (unlikely (klass1 >= class1Count || klass2 >= class2Count)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const Value *v = &values[record_len * (klass1 * class2Count + klass2)];
michael@0:     valueFormat1.apply_value (c->font, c->direction, this,
michael@0: 			      v, buffer->cur_pos());
michael@0:     valueFormat2.apply_value (c->font, c->direction, this,
michael@0: 			      v + len1, buffer->pos[skippy_iter.idx]);
michael@0: 
michael@0:     buffer->idx = skippy_iter.idx;
michael@0:     if (len2)
michael@0:       buffer->idx++;
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!(c->check_struct (this)
michael@0:        && coverage.sanitize (c, this)
michael@0:        && classDef1.sanitize (c, this)
michael@0:        && classDef2.sanitize (c, this))) return TRACE_RETURN (false);
michael@0: 
michael@0:     unsigned int len1 = valueFormat1.get_len ();
michael@0:     unsigned int len2 = valueFormat2.get_len ();
michael@0:     unsigned int stride = len1 + len2;
michael@0:     unsigned int record_size = valueFormat1.get_size () + valueFormat2.get_size ();
michael@0:     unsigned int count = (unsigned int) class1Count * (unsigned int) class2Count;
michael@0:     return TRACE_RETURN (c->check_array (values, record_size, count) &&
michael@0: 			 valueFormat1.sanitize_values_stride_unsafe (c, this, &values[0], count, stride) &&
michael@0: 			 valueFormat2.sanitize_values_stride_unsafe (c, this, &values[len1], count, stride));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 2 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of subtable */
michael@0:   ValueFormat	valueFormat1;		/* ValueRecord definition--for the
michael@0: 					 * first glyph of the pair--may be zero
michael@0: 					 * (0) */
michael@0:   ValueFormat	valueFormat2;		/* ValueRecord definition--for the
michael@0: 					 * second glyph of the pair--may be
michael@0: 					 * zero (0) */
michael@0:   OffsetTo<ClassDef>
michael@0: 		classDef1;		/* Offset to ClassDef table--from
michael@0: 					 * beginning of PairPos subtable--for
michael@0: 					 * the first glyph of the pair */
michael@0:   OffsetTo<ClassDef>
michael@0: 		classDef2;		/* Offset to ClassDef table--from
michael@0: 					 * beginning of PairPos subtable--for
michael@0: 					 * the second glyph of the pair */
michael@0:   USHORT	class1Count;		/* Number of classes in ClassDef1
michael@0: 					 * table--includes Class0 */
michael@0:   USHORT	class2Count;		/* Number of classes in ClassDef2
michael@0: 					 * table--includes Class0 */
michael@0:   ValueRecord	values;			/* Matrix of value pairs:
michael@0: 					 * class1-major, class2-minor,
michael@0: 					 * Each entry has value1 and value2 */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (16, values);
michael@0: };
michael@0: 
michael@0: struct PairPos
michael@0: {
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
michael@0:     case 2: return TRACE_RETURN (c->dispatch (u.format2));
michael@0:     default:return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     case 2: return TRACE_RETURN (u.format2.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   PairPosFormat1	format1;
michael@0:   PairPosFormat2	format2;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: struct EntryExitRecord
michael@0: {
michael@0:   friend struct CursivePosFormat1;
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, void *base) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (entryAnchor.sanitize (c, base) && exitAnchor.sanitize (c, base));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   OffsetTo<Anchor>
michael@0: 		entryAnchor;		/* Offset to EntryAnchor table--from
michael@0: 					 * beginning of CursivePos
michael@0: 					 * subtable--may be NULL */
michael@0:   OffsetTo<Anchor>
michael@0: 		exitAnchor;		/* Offset to ExitAnchor table--from
michael@0: 					 * beginning of CursivePos
michael@0: 					 * subtable--may be NULL */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (4);
michael@0: };
michael@0: 
michael@0: struct CursivePosFormat1
michael@0: {
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage).add_coverage (c->input);
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0: 
michael@0:     /* We don't handle mark glyphs here. */
michael@0:     if (unlikely (_hb_glyph_info_is_mark (&buffer->cur()))) return TRACE_RETURN (false);
michael@0: 
michael@0:     hb_apply_context_t::skipping_forward_iterator_t skippy_iter (c, buffer->idx, 1);
michael@0:     if (skippy_iter.has_no_chance ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     const EntryExitRecord &this_record = entryExitRecord[(this+coverage).get_coverage  (buffer->cur().codepoint)];
michael@0:     if (!this_record.exitAnchor) return TRACE_RETURN (false);
michael@0: 
michael@0:     if (!skippy_iter.next ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     const EntryExitRecord &next_record = entryExitRecord[(this+coverage).get_coverage  (buffer->info[skippy_iter.idx].codepoint)];
michael@0:     if (!next_record.entryAnchor) return TRACE_RETURN (false);
michael@0: 
michael@0:     unsigned int i = buffer->idx;
michael@0:     unsigned int j = skippy_iter.idx;
michael@0: 
michael@0:     hb_position_t entry_x, entry_y, exit_x, exit_y;
michael@0:     (this+this_record.exitAnchor).get_anchor (c->font, buffer->info[i].codepoint, &exit_x, &exit_y);
michael@0:     (this+next_record.entryAnchor).get_anchor (c->font, buffer->info[j].codepoint, &entry_x, &entry_y);
michael@0: 
michael@0:     hb_glyph_position_t *pos = buffer->pos;
michael@0: 
michael@0:     hb_position_t d;
michael@0:     /* Main-direction adjustment */
michael@0:     switch (c->direction) {
michael@0:       case HB_DIRECTION_LTR:
michael@0: 	pos[i].x_advance  =  exit_x + pos[i].x_offset;
michael@0: 
michael@0: 	d = entry_x + pos[j].x_offset;
michael@0: 	pos[j].x_advance -= d;
michael@0: 	pos[j].x_offset  -= d;
michael@0: 	break;
michael@0:       case HB_DIRECTION_RTL:
michael@0: 	d = exit_x + pos[i].x_offset;
michael@0: 	pos[i].x_advance -= d;
michael@0: 	pos[i].x_offset  -= d;
michael@0: 
michael@0: 	pos[j].x_advance  =  entry_x + pos[j].x_offset;
michael@0: 	break;
michael@0:       case HB_DIRECTION_TTB:
michael@0: 	pos[i].y_advance  =  exit_y + pos[i].y_offset;
michael@0: 
michael@0: 	d = entry_y + pos[j].y_offset;
michael@0: 	pos[j].y_advance -= d;
michael@0: 	pos[j].y_offset  -= d;
michael@0: 	break;
michael@0:       case HB_DIRECTION_BTT:
michael@0: 	d = exit_y + pos[i].y_offset;
michael@0: 	pos[i].y_advance -= d;
michael@0: 	pos[i].y_offset  -= d;
michael@0: 
michael@0: 	pos[j].y_advance  =  entry_y;
michael@0: 	break;
michael@0:       case HB_DIRECTION_INVALID:
michael@0:       default:
michael@0: 	break;
michael@0:     }
michael@0: 
michael@0:     /* Cross-direction adjustment */
michael@0:     if  (c->lookup_props & LookupFlag::RightToLeft) {
michael@0:       pos[i].cursive_chain() = j - i;
michael@0:       if (likely (HB_DIRECTION_IS_HORIZONTAL (c->direction)))
michael@0: 	pos[i].y_offset = entry_y - exit_y;
michael@0:       else
michael@0: 	pos[i].x_offset = entry_x - exit_x;
michael@0:     } else {
michael@0:       pos[j].cursive_chain() = i - j;
michael@0:       if (likely (HB_DIRECTION_IS_HORIZONTAL (c->direction)))
michael@0: 	pos[j].y_offset = exit_y - entry_y;
michael@0:       else
michael@0: 	pos[j].x_offset = exit_x - entry_x;
michael@0:     }
michael@0: 
michael@0:     buffer->idx = j;
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (coverage.sanitize (c, this) && entryExitRecord.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of subtable */
michael@0:   ArrayOf<EntryExitRecord>
michael@0: 		entryExitRecord;	/* Array of EntryExit records--in
michael@0: 					 * Coverage Index order */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (6, entryExitRecord);
michael@0: };
michael@0: 
michael@0: struct CursivePos
michael@0: {
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
michael@0:     default:return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   CursivePosFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: typedef AnchorMatrix BaseArray;		/* base-major--
michael@0: 					 * in order of BaseCoverage Index--,
michael@0: 					 * mark-minor--
michael@0: 					 * ordered by class--zero-based. */
michael@0: 
michael@0: struct MarkBasePosFormat1
michael@0: {
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+markCoverage).add_coverage (c->input);
michael@0:     (this+baseCoverage).add_coverage (c->input);
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+markCoverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     unsigned int mark_index = (this+markCoverage).get_coverage  (buffer->cur().codepoint);
michael@0:     if (likely (mark_index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     /* now we search backwards for a non-mark glyph */
michael@0:     hb_apply_context_t::skipping_backward_iterator_t skippy_iter (c, buffer->idx, 1);
michael@0:     skippy_iter.set_lookup_props (LookupFlag::IgnoreMarks);
michael@0:     do {
michael@0:       if (!skippy_iter.prev ()) return TRACE_RETURN (false);
michael@0:       /* We only want to attach to the first of a MultipleSubst sequence.  Reject others. */
michael@0:       if (0 == _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx])) break;
michael@0:       skippy_iter.reject ();
michael@0:     } while (1);
michael@0: 
michael@0:     /* Checking that matched glyph is actually a base glyph by GDEF is too strong; disabled */
michael@0:     if (!_hb_glyph_info_is_base_glyph (&buffer->info[skippy_iter.idx])) { /*return TRACE_RETURN (false);*/ }
michael@0: 
michael@0:     unsigned int base_index = (this+baseCoverage).get_coverage  (buffer->info[skippy_iter.idx].codepoint);
michael@0:     if (base_index == NOT_COVERED) return TRACE_RETURN (false);
michael@0: 
michael@0:     return TRACE_RETURN ((this+markArray).apply (c, mark_index, base_index, this+baseArray, classCount, skippy_iter.idx));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this) && markCoverage.sanitize (c, this) && baseCoverage.sanitize (c, this) &&
michael@0: 			 markArray.sanitize (c, this) && baseArray.sanitize (c, this, (unsigned int) classCount));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   OffsetTo<Coverage>
michael@0: 		markCoverage;		/* Offset to MarkCoverage table--from
michael@0: 					 * beginning of MarkBasePos subtable */
michael@0:   OffsetTo<Coverage>
michael@0: 		baseCoverage;		/* Offset to BaseCoverage table--from
michael@0: 					 * beginning of MarkBasePos subtable */
michael@0:   USHORT	classCount;		/* Number of classes defined for marks */
michael@0:   OffsetTo<MarkArray>
michael@0: 		markArray;		/* Offset to MarkArray table--from
michael@0: 					 * beginning of MarkBasePos subtable */
michael@0:   OffsetTo<BaseArray>
michael@0: 		baseArray;		/* Offset to BaseArray table--from
michael@0: 					 * beginning of MarkBasePos subtable */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (12);
michael@0: };
michael@0: 
michael@0: struct MarkBasePos
michael@0: {
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
michael@0:     default:return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   MarkBasePosFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: typedef AnchorMatrix LigatureAttach;	/* component-major--
michael@0: 					 * in order of writing direction--,
michael@0: 					 * mark-minor--
michael@0: 					 * ordered by class--zero-based. */
michael@0: 
michael@0: typedef OffsetListOf<LigatureAttach> LigatureArray;
michael@0: 					/* Array of LigatureAttach
michael@0: 					 * tables ordered by
michael@0: 					 * LigatureCoverage Index */
michael@0: 
michael@0: struct MarkLigPosFormat1
michael@0: {
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+markCoverage).add_coverage (c->input);
michael@0:     (this+ligatureCoverage).add_coverage (c->input);
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+markCoverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     unsigned int mark_index = (this+markCoverage).get_coverage  (buffer->cur().codepoint);
michael@0:     if (likely (mark_index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     /* now we search backwards for a non-mark glyph */
michael@0:     hb_apply_context_t::skipping_backward_iterator_t skippy_iter (c, buffer->idx, 1);
michael@0:     skippy_iter.set_lookup_props (LookupFlag::IgnoreMarks);
michael@0:     if (!skippy_iter.prev ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     /* Checking that matched glyph is actually a ligature by GDEF is too strong; disabled */
michael@0:     if (!_hb_glyph_info_is_ligature (&buffer->info[skippy_iter.idx])) { /*return TRACE_RETURN (false);*/ }
michael@0: 
michael@0:     unsigned int j = skippy_iter.idx;
michael@0:     unsigned int lig_index = (this+ligatureCoverage).get_coverage  (buffer->info[j].codepoint);
michael@0:     if (lig_index == NOT_COVERED) return TRACE_RETURN (false);
michael@0: 
michael@0:     const LigatureArray& lig_array = this+ligatureArray;
michael@0:     const LigatureAttach& lig_attach = lig_array[lig_index];
michael@0: 
michael@0:     /* Find component to attach to */
michael@0:     unsigned int comp_count = lig_attach.rows;
michael@0:     if (unlikely (!comp_count)) return TRACE_RETURN (false);
michael@0: 
michael@0:     /* We must now check whether the ligature ID of the current mark glyph
michael@0:      * is identical to the ligature ID of the found ligature.  If yes, we
michael@0:      * can directly use the component index.  If not, we attach the mark
michael@0:      * glyph to the last component of the ligature. */
michael@0:     unsigned int comp_index;
michael@0:     unsigned int lig_id = _hb_glyph_info_get_lig_id (&buffer->info[j]);
michael@0:     unsigned int mark_id = _hb_glyph_info_get_lig_id (&buffer->cur());
michael@0:     unsigned int mark_comp = _hb_glyph_info_get_lig_comp (&buffer->cur());
michael@0:     if (lig_id && lig_id == mark_id && mark_comp > 0)
michael@0:       comp_index = MIN (comp_count, _hb_glyph_info_get_lig_comp (&buffer->cur())) - 1;
michael@0:     else
michael@0:       comp_index = comp_count - 1;
michael@0: 
michael@0:     return TRACE_RETURN ((this+markArray).apply (c, mark_index, comp_index, lig_attach, classCount, j));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this) && markCoverage.sanitize (c, this) && ligatureCoverage.sanitize (c, this) &&
michael@0: 			 markArray.sanitize (c, this) && ligatureArray.sanitize (c, this, (unsigned int) classCount));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   OffsetTo<Coverage>
michael@0: 		markCoverage;		/* Offset to Mark Coverage table--from
michael@0: 					 * beginning of MarkLigPos subtable */
michael@0:   OffsetTo<Coverage>
michael@0: 		ligatureCoverage;	/* Offset to Ligature Coverage
michael@0: 					 * table--from beginning of MarkLigPos
michael@0: 					 * subtable */
michael@0:   USHORT	classCount;		/* Number of defined mark classes */
michael@0:   OffsetTo<MarkArray>
michael@0: 		markArray;		/* Offset to MarkArray table--from
michael@0: 					 * beginning of MarkLigPos subtable */
michael@0:   OffsetTo<LigatureArray>
michael@0: 		ligatureArray;		/* Offset to LigatureArray table--from
michael@0: 					 * beginning of MarkLigPos subtable */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (12);
michael@0: };
michael@0: 
michael@0: struct MarkLigPos
michael@0: {
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
michael@0:     default:return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   MarkLigPosFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: typedef AnchorMatrix Mark2Array;	/* mark2-major--
michael@0: 					 * in order of Mark2Coverage Index--,
michael@0: 					 * mark1-minor--
michael@0: 					 * ordered by class--zero-based. */
michael@0: 
michael@0: struct MarkMarkPosFormat1
michael@0: {
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+mark1Coverage).add_coverage (c->input);
michael@0:     (this+mark2Coverage).add_coverage (c->input);
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+mark1Coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_buffer_t *buffer = c->buffer;
michael@0:     unsigned int mark1_index = (this+mark1Coverage).get_coverage  (buffer->cur().codepoint);
michael@0:     if (likely (mark1_index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     /* now we search backwards for a suitable mark glyph until a non-mark glyph */
michael@0:     hb_apply_context_t::skipping_backward_iterator_t skippy_iter (c, buffer->idx, 1);
michael@0:     skippy_iter.set_lookup_props (c->lookup_props & ~LookupFlag::IgnoreFlags);
michael@0:     if (!skippy_iter.prev ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     if (!_hb_glyph_info_is_mark (&buffer->info[skippy_iter.idx])) { return TRACE_RETURN (false); }
michael@0: 
michael@0:     unsigned int j = skippy_iter.idx;
michael@0: 
michael@0:     unsigned int id1 = _hb_glyph_info_get_lig_id (&buffer->cur());
michael@0:     unsigned int id2 = _hb_glyph_info_get_lig_id (&buffer->info[j]);
michael@0:     unsigned int comp1 = _hb_glyph_info_get_lig_comp (&buffer->cur());
michael@0:     unsigned int comp2 = _hb_glyph_info_get_lig_comp (&buffer->info[j]);
michael@0: 
michael@0:     if (likely (id1 == id2)) {
michael@0:       if (id1 == 0) /* Marks belonging to the same base. */
michael@0: 	goto good;
michael@0:       else if (comp1 == comp2) /* Marks belonging to the same ligature component. */
michael@0:         goto good;
michael@0:     } else {
michael@0:       /* If ligature ids don't match, it may be the case that one of the marks
michael@0:        * itself is a ligature.  In which case match. */
michael@0:       if ((id1 > 0 && !comp1) || (id2 > 0 && !comp2))
michael@0: 	goto good;
michael@0:     }
michael@0: 
michael@0:     /* Didn't match. */
michael@0:     return TRACE_RETURN (false);
michael@0: 
michael@0:     good:
michael@0:     unsigned int mark2_index = (this+mark2Coverage).get_coverage  (buffer->info[j].codepoint);
michael@0:     if (mark2_index == NOT_COVERED) return TRACE_RETURN (false);
michael@0: 
michael@0:     return TRACE_RETURN ((this+mark1Array).apply (c, mark1_index, mark2_index, this+mark2Array, classCount, j));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this) && mark1Coverage.sanitize (c, this) &&
michael@0: 			 mark2Coverage.sanitize (c, this) && mark1Array.sanitize (c, this)
michael@0: 			 && mark2Array.sanitize (c, this, (unsigned int) classCount));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   OffsetTo<Coverage>
michael@0: 		mark1Coverage;		/* Offset to Combining Mark1 Coverage
michael@0: 					 * table--from beginning of MarkMarkPos
michael@0: 					 * subtable */
michael@0:   OffsetTo<Coverage>
michael@0: 		mark2Coverage;		/* Offset to Combining Mark2 Coverage
michael@0: 					 * table--from beginning of MarkMarkPos
michael@0: 					 * subtable */
michael@0:   USHORT	classCount;		/* Number of defined mark classes */
michael@0:   OffsetTo<MarkArray>
michael@0: 		mark1Array;		/* Offset to Mark1Array table--from
michael@0: 					 * beginning of MarkMarkPos subtable */
michael@0:   OffsetTo<Mark2Array>
michael@0: 		mark2Array;		/* Offset to Mark2Array table--from
michael@0: 					 * beginning of MarkMarkPos subtable */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (12);
michael@0: };
michael@0: 
michael@0: struct MarkMarkPos
michael@0: {
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
michael@0:     default:return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   MarkMarkPosFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: struct ContextPos : Context {};
michael@0: 
michael@0: struct ChainContextPos : ChainContext {};
michael@0: 
michael@0: struct ExtensionPos : Extension<ExtensionPos>
michael@0: {
michael@0:   typedef struct PosLookupSubTable LookupSubTable;
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * PosLookup
michael@0:  */
michael@0: 
michael@0: 
michael@0: struct PosLookupSubTable
michael@0: {
michael@0:   friend struct PosLookup;
michael@0: 
michael@0:   enum Type {
michael@0:     Single		= 1,
michael@0:     Pair		= 2,
michael@0:     Cursive		= 3,
michael@0:     MarkBase		= 4,
michael@0:     MarkLig		= 5,
michael@0:     MarkMark		= 6,
michael@0:     Context		= 7,
michael@0:     ChainContext	= 8,
michael@0:     Extension		= 9
michael@0:   };
michael@0: 
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c, unsigned int lookup_type) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (lookup_type) {
michael@0:     case Single:		return TRACE_RETURN (u.single.dispatch (c));
michael@0:     case Pair:			return TRACE_RETURN (u.pair.dispatch (c));
michael@0:     case Cursive:		return TRACE_RETURN (u.cursive.dispatch (c));
michael@0:     case MarkBase:		return TRACE_RETURN (u.markBase.dispatch (c));
michael@0:     case MarkLig:		return TRACE_RETURN (u.markLig.dispatch (c));
michael@0:     case MarkMark:		return TRACE_RETURN (u.markMark.dispatch (c));
michael@0:     case Context:		return TRACE_RETURN (u.context.dispatch (c));
michael@0:     case ChainContext:		return TRACE_RETURN (u.chainContext.dispatch (c));
michael@0:     case Extension:		return TRACE_RETURN (u.extension.dispatch (c));
michael@0:     default:			return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, unsigned int lookup_type) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.header.sub_format.sanitize (c))
michael@0:       return TRACE_RETURN (false);
michael@0:     switch (lookup_type) {
michael@0:     case Single:		return TRACE_RETURN (u.single.sanitize (c));
michael@0:     case Pair:			return TRACE_RETURN (u.pair.sanitize (c));
michael@0:     case Cursive:		return TRACE_RETURN (u.cursive.sanitize (c));
michael@0:     case MarkBase:		return TRACE_RETURN (u.markBase.sanitize (c));
michael@0:     case MarkLig:		return TRACE_RETURN (u.markLig.sanitize (c));
michael@0:     case MarkMark:		return TRACE_RETURN (u.markMark.sanitize (c));
michael@0:     case Context:		return TRACE_RETURN (u.context.sanitize (c));
michael@0:     case ChainContext:		return TRACE_RETURN (u.chainContext.sanitize (c));
michael@0:     case Extension:		return TRACE_RETURN (u.extension.sanitize (c));
michael@0:     default:			return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   struct {
michael@0:     USHORT		sub_format;
michael@0:   } header;
michael@0:   SinglePos		single;
michael@0:   PairPos		pair;
michael@0:   CursivePos		cursive;
michael@0:   MarkBasePos		markBase;
michael@0:   MarkLigPos		markLig;
michael@0:   MarkMarkPos		markMark;
michael@0:   ContextPos		context;
michael@0:   ChainContextPos	chainContext;
michael@0:   ExtensionPos		extension;
michael@0:   } u;
michael@0:   public:
michael@0:   DEFINE_SIZE_UNION (2, header.sub_format);
michael@0: };
michael@0: 
michael@0: 
michael@0: struct PosLookup : Lookup
michael@0: {
michael@0:   inline const PosLookupSubTable& get_subtable (unsigned int i) const
michael@0:   { return this+CastR<OffsetArrayOf<PosLookupSubTable> > (subTable)[i]; }
michael@0: 
michael@0:   inline bool is_reverse (void) const
michael@0:   {
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   inline hb_collect_glyphs_context_t::return_t collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     c->set_recurse_func (NULL);
michael@0:     return TRACE_RETURN (dispatch (c));
michael@0:   }
michael@0: 
michael@0:   template <typename set_t>
michael@0:   inline void add_coverage (set_t *glyphs) const
michael@0:   {
michael@0:     hb_get_coverage_context_t c;
michael@0:     const Coverage *last = NULL;
michael@0:     unsigned int count = get_subtable_count ();
michael@0:     for (unsigned int i = 0; i < count; i++) {
michael@0:       const Coverage *coverage = &get_subtable (i).dispatch (&c, get_type ());
michael@0:       if (coverage != last) {
michael@0:         coverage->add_coverage (glyphs);
michael@0:         last = coverage;
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool apply_once (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     if (!c->check_glyph_property (&c->buffer->cur(), c->lookup_props))
michael@0:       return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (dispatch (c));
michael@0:   }
michael@0: 
michael@0:   static bool apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index);
michael@0: 
michael@0:   template <typename context_t>
michael@0:   static inline typename context_t::return_t dispatch_recurse_func (context_t *c, unsigned int lookup_index);
michael@0: 
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     unsigned int lookup_type = get_type ();
michael@0:     unsigned int count = get_subtable_count ();
michael@0:     for (unsigned int i = 0; i < count; i++) {
michael@0:       typename context_t::return_t r = get_subtable (i).dispatch (c, lookup_type);
michael@0:       if (c->stop_sublookup_iteration (r))
michael@0:         return TRACE_RETURN (r);
michael@0:     }
michael@0:     return TRACE_RETURN (c->default_return_value ());
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!Lookup::sanitize (c))) return TRACE_RETURN (false);
michael@0:     OffsetArrayOf<PosLookupSubTable> &list = CastR<OffsetArrayOf<PosLookupSubTable> > (subTable);
michael@0:     return TRACE_RETURN (list.sanitize (c, this, get_type ()));
michael@0:   }
michael@0: };
michael@0: 
michael@0: typedef OffsetListOf<PosLookup> PosLookupList;
michael@0: 
michael@0: /*
michael@0:  * GPOS -- The Glyph Positioning Table
michael@0:  */
michael@0: 
michael@0: struct GPOS : GSUBGPOS
michael@0: {
michael@0:   static const hb_tag_t tableTag	= HB_OT_TAG_GPOS;
michael@0: 
michael@0:   inline const PosLookup& get_lookup (unsigned int i) const
michael@0:   { return CastR<PosLookup> (GSUBGPOS::get_lookup (i)); }
michael@0: 
michael@0:   static inline void position_start (hb_font_t *font, hb_buffer_t *buffer);
michael@0:   static inline void position_finish (hb_font_t *font, hb_buffer_t *buffer);
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!GSUBGPOS::sanitize (c))) return TRACE_RETURN (false);
michael@0:     OffsetTo<PosLookupList> &list = CastR<OffsetTo<PosLookupList> > (lookupList);
michael@0:     return TRACE_RETURN (list.sanitize (c, this));
michael@0:   }
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (10);
michael@0: };
michael@0: 
michael@0: 
michael@0: static void
michael@0: fix_cursive_minor_offset (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction)
michael@0: {
michael@0:   unsigned int j = pos[i].cursive_chain();
michael@0:   if (likely (!j))
michael@0:     return;
michael@0: 
michael@0:   j += i;
michael@0: 
michael@0:   pos[i].cursive_chain() = 0;
michael@0: 
michael@0:   fix_cursive_minor_offset (pos, j, direction);
michael@0: 
michael@0:   if (HB_DIRECTION_IS_HORIZONTAL (direction))
michael@0:     pos[i].y_offset += pos[j].y_offset;
michael@0:   else
michael@0:     pos[i].x_offset += pos[j].x_offset;
michael@0: }
michael@0: 
michael@0: static void
michael@0: fix_mark_attachment (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction)
michael@0: {
michael@0:   if (likely (!(pos[i].attach_lookback())))
michael@0:     return;
michael@0: 
michael@0:   unsigned int j = i - pos[i].attach_lookback();
michael@0: 
michael@0:   pos[i].x_offset += pos[j].x_offset;
michael@0:   pos[i].y_offset += pos[j].y_offset;
michael@0: 
michael@0:   if (HB_DIRECTION_IS_FORWARD (direction))
michael@0:     for (unsigned int k = j; k < i; k++) {
michael@0:       pos[i].x_offset -= pos[k].x_advance;
michael@0:       pos[i].y_offset -= pos[k].y_advance;
michael@0:     }
michael@0:   else
michael@0:     for (unsigned int k = j + 1; k < i + 1; k++) {
michael@0:       pos[i].x_offset += pos[k].x_advance;
michael@0:       pos[i].y_offset += pos[k].y_advance;
michael@0:     }
michael@0: }
michael@0: 
michael@0: void
michael@0: GPOS::position_start (hb_font_t *font HB_UNUSED, hb_buffer_t *buffer)
michael@0: {
michael@0:   buffer->clear_positions ();
michael@0: 
michael@0:   unsigned int count = buffer->len;
michael@0:   for (unsigned int i = 0; i < count; i++)
michael@0:     buffer->pos[i].attach_lookback() = buffer->pos[i].cursive_chain() = 0;
michael@0: }
michael@0: 
michael@0: void
michael@0: GPOS::position_finish (hb_font_t *font HB_UNUSED, hb_buffer_t *buffer)
michael@0: {
michael@0:   unsigned int len;
michael@0:   hb_glyph_position_t *pos = hb_buffer_get_glyph_positions (buffer, &len);
michael@0:   hb_direction_t direction = buffer->props.direction;
michael@0: 
michael@0:   /* Handle cursive connections */
michael@0:   for (unsigned int i = 0; i < len; i++)
michael@0:     fix_cursive_minor_offset (pos, i, direction);
michael@0: 
michael@0:   /* Handle attachments */
michael@0:   for (unsigned int i = 0; i < len; i++)
michael@0:     fix_mark_attachment (pos, i, direction);
michael@0: 
michael@0:   _hb_buffer_deallocate_gsubgpos_vars (buffer);
michael@0: }
michael@0: 
michael@0: 
michael@0: /* Out-of-class implementation for methods recursing */
michael@0: 
michael@0: template <typename context_t>
michael@0: inline typename context_t::return_t PosLookup::dispatch_recurse_func (context_t *c, unsigned int lookup_index)
michael@0: {
michael@0:   const GPOS &gpos = *(hb_ot_layout_from_face (c->face)->gpos);
michael@0:   const PosLookup &l = gpos.get_lookup (lookup_index);
michael@0:   return l.dispatch (c);
michael@0: }
michael@0: 
michael@0: inline bool PosLookup::apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index)
michael@0: {
michael@0:   const GPOS &gpos = *(hb_ot_layout_from_face (c->face)->gpos);
michael@0:   const PosLookup &l = gpos.get_lookup (lookup_index);
michael@0:   unsigned int saved_lookup_props = c->lookup_props;
michael@0:   c->set_lookup (l);
michael@0:   bool ret = l.apply_once (c);
michael@0:   c->lookup_props = saved_lookup_props;
michael@0:   return ret;
michael@0: }
michael@0: 
michael@0: 
michael@0: #undef attach_lookback
michael@0: #undef cursive_chain
michael@0: 
michael@0: 
michael@0: } /* namespace OT */
michael@0: 
michael@0: 
michael@0: #endif /* HB_OT_LAYOUT_GPOS_TABLE_HH */