kc3-lang/harfbuzz/src/hb-ot-layout-private.hh

• Show log

  Commit

• Hash : a3313e54
  Author :
  Date : 2012-07-25T18:37:51
  

  [GPOS] Fix MarkMarkPos applied to results of MultipleSubst
  
  This was broken as a result of 7b84c536c10ab90ed96a033d88e9ad232d46c5b8.
  As Khaled reported, MarkMark positioning was broken with glyphs
  resulting from a MultipleSubst.  Fixed.  Test with the ALLAH character
  in Amiri.
  

Download

• src/hb-ot-layout-private.hh

• /*
   * Copyright © 2007,2008,2009  Red Hat, 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
   */
  
  #ifndef HB_OT_LAYOUT_PRIVATE_HH
  #define HB_OT_LAYOUT_PRIVATE_HH
  
  #include "hb-private.hh"
  
  #include "hb-ot-layout.h"
  
  #include "hb-font-private.hh"
  #include "hb-buffer-private.hh"
  #include "hb-ot-shape-complex-private.hh"
  
  
  
  /*
   * GDEF
   */
  
  /* XXX cleanup */
  typedef enum {
    HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED	= 0x0001,
    HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH	= 0x0002,
    HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE	= 0x0004,
    HB_OT_LAYOUT_GLYPH_CLASS_MARK		= 0x0008,
    HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT	= 0x0010
  } hb_ot_layout_glyph_class_t;
  
  
  HB_INTERNAL hb_bool_t
  _hb_ot_layout_check_glyph_property (hb_face_t    *face,
  				    hb_glyph_info_t *ginfo,
  				    unsigned int  lookup_props,
  				    unsigned int *property_out);
  
  HB_INTERNAL hb_bool_t
  _hb_ot_layout_skip_mark (hb_face_t    *face,
  			 hb_glyph_info_t *ginfo,
  			 unsigned int  lookup_props,
  			 unsigned int *property_out);
  
  
  /*
   * GSUB/GPOS
   */
  
  /* lig_id / lig_comp
   *
   * When a ligature is formed:
   *
   *   - The ligature glyph and any marks in between all get a unique lig_id,
   *   - The ligature glyph will get lig_comp = 0
   *   - The marks get lig_comp > 0, reflecting which component of the ligature
   *     they were applied to.
   *   - This is used in GPOS to attach marks to the right component of a ligature
   *     in MarkLigPos.
   *
   * When a multiple-substitution is done:
   *
   *   - All resulting glyphs will have lig_id = 0,
   *   - The resulting glyphs will have lig_comp = 0, 1, 2, ... respectively.
   *   - This is used in GPOS to attack marks to the first component of a
   *     multiple substitution in MarkBasePos.
   *
   * The numbers are also used in GPOS to do mark-to-mark positioning only
   * to marks that belong to the same component of a ligature in MarkMarPos.
   */
  static inline void
  set_lig_props (hb_glyph_info_t &info, unsigned int lig_id, unsigned int lig_comp)
  {
    info.lig_props() = (lig_id << 4) | (lig_comp & 0x0F);
  }
  static inline unsigned int
  get_lig_id (const hb_glyph_info_t &info)
  {
    return info.lig_props() >> 4;
  }
  static inline unsigned int
  get_lig_comp (const hb_glyph_info_t &info)
  {
    return info.lig_props() & 0x0F;
  }
  static inline bool
  is_a_ligature (const hb_glyph_info_t &info)
  {
    return unlikely (get_lig_id (info) && ~get_lig_comp (info));
  }
  
  static inline uint8_t allocate_lig_id (hb_buffer_t *buffer) {
    uint8_t lig_id = buffer->next_serial () & 0x0F;
    if (unlikely (!lig_id))
      lig_id = allocate_lig_id (buffer); /* in case of overflow */
    return lig_id;
  }
  
  
  
  /*
   * hb_ot_layout_t
   */
  
  struct hb_ot_layout_t
  {
    hb_blob_t *gdef_blob;
    hb_blob_t *gsub_blob;
    hb_blob_t *gpos_blob;
  
    const struct GDEF *gdef;
    const struct GSUB *gsub;
    const struct GPOS *gpos;
  };
  
  
  HB_INTERNAL hb_ot_layout_t *
  _hb_ot_layout_create (hb_face_t *face);
  
  HB_INTERNAL void
  _hb_ot_layout_destroy (hb_ot_layout_t *layout);
  
  
  
  #endif /* HB_OT_LAYOUT_PRIVATE_HH */
  

Download