The Tor Browser: gfx/harfbuzz/src/hb-ot-shape-complex-sea.cc@925c144e1f1f (annotated)

gfx/harfbuzz/src/hb-ot-shape-complex-sea.cc@925c144e1f1f (annotated)

gfx/harfbuzz/src/hb-ot-shape-complex-sea.cc

Fri, 16 Jan 2015 18:13:44 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Fri, 16 Jan 2015 18:13:44 +0100
branch: TOR_BUG_9701
changeset 14: 925c144e1f1f
permissions: -rw-r--r--

Integrate suggestion from review to improve consistency with existing code.

 /*
  * Copyright © 2011,2012,2013  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.
  *
  * Google Author(s): Behdad Esfahbod
  */
 #include "hb-ot-shape-complex-indic-private.hh"
 /* buffer var allocations */
 #define sea_category() complex_var_u8_0() /* indic_category_t */
 #define sea_position() complex_var_u8_1() /* indic_position_t */
 /*
  * South-East Asian shaper.
  * Loosely based on the Myanmar spec / shaper.
  * There is no OpenType spec for this.
  */
 static const hb_tag_t
 basic_features[] =
 {
   /*
    * Basic features.
    * These features are applied in order, one at a time, after initial_reordering.
    */
   HB_TAG('p','r','e','f'),
   HB_TAG('a','b','v','f'),
   HB_TAG('b','l','w','f'),
   HB_TAG('p','s','t','f'),
 };
 static const hb_tag_t
 other_features[] =
 {
   /*
    * Other features.
    * These features are applied all at once, after final_reordering.
    */
   HB_TAG('p','r','e','s'),
   HB_TAG('a','b','v','s'),
   HB_TAG('b','l','w','s'),
   HB_TAG('p','s','t','s'),
   /* Positioning features, though we don't care about the types. */
   HB_TAG('d','i','s','t'),
 };
 static void
 setup_syllables (const hb_ot_shape_plan_t *plan,
 		 hb_font_t *font,
 		 hb_buffer_t *buffer);
 static void
 initial_reordering (const hb_ot_shape_plan_t *plan,
 		    hb_font_t *font,
 		    hb_buffer_t *buffer);
 static void
 final_reordering (const hb_ot_shape_plan_t *plan,
 		  hb_font_t *font,
 		  hb_buffer_t *buffer);
 static void
 collect_features_sea (hb_ot_shape_planner_t *plan)
 {
   hb_ot_map_builder_t *map = &plan->map;
   /* Do this before any lookups have been applied. */
   map->add_gsub_pause (setup_syllables);
   map->add_global_bool_feature (HB_TAG('l','o','c','l'));
   /* The Indic specs do not require ccmp, but we apply it here since if
    * there is a use of it, it's typically at the beginning. */
   map->add_global_bool_feature (HB_TAG('c','c','m','p'));
   map->add_gsub_pause (initial_reordering);
   for (unsigned int i = 0; i < ARRAY_LENGTH (basic_features); i++)
   {
     map->add_feature (basic_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ);
     map->add_gsub_pause (NULL);
   }
   map->add_gsub_pause (final_reordering);
   for (unsigned int i = 0; i < ARRAY_LENGTH (other_features); i++)
     map->add_feature (other_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ);
 }
 static void
 override_features_sea (hb_ot_shape_planner_t *plan)
 {
   plan->map.add_feature (HB_TAG('l','i','g','a'), 0, F_GLOBAL);
 }
 enum syllable_type_t {
   consonant_syllable,
   broken_cluster,
   non_sea_cluster,
 };
 #include "hb-ot-shape-complex-sea-machine.hh"
 /* Note: This enum is duplicated in the -machine.rl source file.
  * Not sure how to avoid duplication. */
 enum sea_category_t {
 //  OT_C    = 1,
   OT_GB   = 12, /* Generic Base XXX DOTTED CIRCLE only for now */
 //  OT_H    = 4,  /* Halant */
   OT_IV   = 2,  /* Independent Vowel */
   OT_MR   = 22, /* Medial Ra */
 //  OT_CM   = 17, /* Consonant Medial */
   OT_VAbv = 26,
   OT_VBlw = 27,
   OT_VPre = 28,
   OT_VPst = 29,
   OT_T    = 3,  /* Tone Marks */
 //  OT_A    = 10, /* Anusvara */
 };
 static inline void
 set_sea_properties (hb_glyph_info_t &info)
 {
   hb_codepoint_t u = info.codepoint;
   unsigned int type = hb_indic_get_categories (u);
   indic_category_t cat = (indic_category_t) (type & 0x7F);
   indic_position_t pos = (indic_position_t) (type >> 8);
   /* Medial Ra */
   if (u == 0x1A55 || u == 0xAA34)
     cat = (indic_category_t) OT_MR;
   if (cat == OT_M)
   {
     switch ((int) pos)
     {
       case POS_PRE_C:	cat = (indic_category_t) OT_VPre; break;
       case POS_ABOVE_C:	cat = (indic_category_t) OT_VAbv; break;
       case POS_BELOW_C:	cat = (indic_category_t) OT_VBlw; break;
       case POS_POST_C:	cat = (indic_category_t) OT_VPst; break;
     }
   }
   info.sea_category() = (sea_category_t) cat;
   info.sea_position() = pos;
 }
 static void
 setup_masks_sea (const hb_ot_shape_plan_t *plan HB_UNUSED,
 		 hb_buffer_t              *buffer,
 		 hb_font_t                *font HB_UNUSED)
 {
   HB_BUFFER_ALLOCATE_VAR (buffer, sea_category);
   HB_BUFFER_ALLOCATE_VAR (buffer, sea_position);
   /* We cannot setup masks here.  We save information about characters
    * and setup masks later on in a pause-callback. */
   unsigned int count = buffer->len;
   for (unsigned int i = 0; i < count; i++)
     set_sea_properties (buffer->info[i]);
 }
 static void
 setup_syllables (const hb_ot_shape_plan_t *plan HB_UNUSED,
 		 hb_font_t *font HB_UNUSED,
 		 hb_buffer_t *buffer)
 {
   find_syllables (buffer);
 }
 static int
 compare_sea_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
 {
   int a = pa->sea_position();
   int b = pb->sea_position();
   return a < b ? -1 : a == b ? 0 : +1;
 }
 static void
 initial_reordering_consonant_syllable (const hb_ot_shape_plan_t *plan,
 				       hb_face_t *face,
 				       hb_buffer_t *buffer,
 				       unsigned int start, unsigned int end)
 {
   hb_glyph_info_t *info = buffer->info;
   unsigned int base = start;
   /* Reorder! */
   unsigned int i = start;
   for (; i < base; i++)
     info[i].sea_position() = POS_PRE_C;
   if (i < end)
   {
     info[i].sea_position() = POS_BASE_C;
     i++;
   }
   for (; i < end; i++)
   {
     if (info[i].sea_category() == OT_MR) /* Pre-base reordering */
     {
       info[i].sea_position() = POS_PRE_C;
       continue;
     }
     if (info[i].sea_category() == OT_VPre) /* Left matra */
     {
       info[i].sea_position() = POS_PRE_M;
       continue;
     }
     info[i].sea_position() = POS_AFTER_MAIN;
   }
   buffer->merge_clusters (start, end);
   /* Sit tight, rock 'n roll! */
   hb_bubble_sort (info + start, end - start, compare_sea_order);
 }
 static void
 initial_reordering_broken_cluster (const hb_ot_shape_plan_t *plan,
 				   hb_face_t *face,
 				   hb_buffer_t *buffer,
 				   unsigned int start, unsigned int end)
 {
   /* We already inserted dotted-circles, so just call the consonant_syllable. */
   initial_reordering_consonant_syllable (plan, face, buffer, start, end);
 }
 static void
 initial_reordering_non_sea_cluster (const hb_ot_shape_plan_t *plan HB_UNUSED,
 				    hb_face_t *face HB_UNUSED,
 				    hb_buffer_t *buffer HB_UNUSED,
 				    unsigned int start HB_UNUSED, unsigned int end HB_UNUSED)
 {
   /* Nothing to do right now.  If we ever switch to using the output
    * buffer in the reordering process, we'd need to next_glyph() here. */
 }
 static void
 initial_reordering_syllable (const hb_ot_shape_plan_t *plan,
 			     hb_face_t *face,
 			     hb_buffer_t *buffer,
 			     unsigned int start, unsigned int end)
 {
   syllable_type_t syllable_type = (syllable_type_t) (buffer->info[start].syllable() & 0x0F);
   switch (syllable_type) {
   case consonant_syllable:	initial_reordering_consonant_syllable  (plan, face, buffer, start, end); return;
   case broken_cluster:		initial_reordering_broken_cluster      (plan, face, buffer, start, end); return;
   case non_sea_cluster:		initial_reordering_non_sea_cluster     (plan, face, buffer, start, end); return;
   }
 }
 static inline void
 insert_dotted_circles (const hb_ot_shape_plan_t *plan HB_UNUSED,
 		       hb_font_t *font,
 		       hb_buffer_t *buffer)
 {
   /* Note: This loop is extra overhead, but should not be measurable. */
   bool has_broken_syllables = false;
   unsigned int count = buffer->len;
   for (unsigned int i = 0; i < count; i++)
     if ((buffer->info[i].syllable() & 0x0F) == broken_cluster) {
       has_broken_syllables = true;
       break;
     }
   if (likely (!has_broken_syllables))
     return;
   hb_codepoint_t dottedcircle_glyph;
   if (!font->get_glyph (0x25CC, 0, &dottedcircle_glyph))
     return;
   hb_glyph_info_t dottedcircle = {0};
   dottedcircle.codepoint = 0x25CC;
   set_sea_properties (dottedcircle);
   dottedcircle.codepoint = dottedcircle_glyph;
   buffer->clear_output ();
   buffer->idx = 0;
   unsigned int last_syllable = 0;
   while (buffer->idx < buffer->len)
   {
     unsigned int syllable = buffer->cur().syllable();
     syllable_type_t syllable_type = (syllable_type_t) (syllable & 0x0F);
     if (unlikely (last_syllable != syllable && syllable_type == broken_cluster))
     {
       last_syllable = syllable;
       hb_glyph_info_t info = dottedcircle;
       info.cluster = buffer->cur().cluster;
       info.mask = buffer->cur().mask;
       info.syllable() = buffer->cur().syllable();
       buffer->output_info (info);
     }
     else
       buffer->next_glyph ();
   }
   buffer->swap_buffers ();
 }
 static void
 initial_reordering (const hb_ot_shape_plan_t *plan,
 		    hb_font_t *font,
 		    hb_buffer_t *buffer)
 {
   insert_dotted_circles (plan, font, buffer);
   hb_glyph_info_t *info = buffer->info;
   unsigned int count = buffer->len;
   if (unlikely (!count)) return;
   unsigned int last = 0;
   unsigned int last_syllable = info[0].syllable();
   for (unsigned int i = 1; i < count; i++)
     if (last_syllable != info[i].syllable()) {
       initial_reordering_syllable (plan, font->face, buffer, last, i);
       last = i;
       last_syllable = info[last].syllable();
     }
   initial_reordering_syllable (plan, font->face, buffer, last, count);
 }
 static void
 final_reordering (const hb_ot_shape_plan_t *plan,
 		  hb_font_t *font HB_UNUSED,
 		  hb_buffer_t *buffer)
 {
   hb_glyph_info_t *info = buffer->info;
   unsigned int count = buffer->len;
   /* Zero syllables now... */
   for (unsigned int i = 0; i < count; i++)
     info[i].syllable() = 0;
   HB_BUFFER_DEALLOCATE_VAR (buffer, sea_category);
   HB_BUFFER_DEALLOCATE_VAR (buffer, sea_position);
 }
 const hb_ot_complex_shaper_t _hb_ot_complex_shaper_sea =
 {
   "sea",
   collect_features_sea,
   override_features_sea,
   NULL, /* data_create */
   NULL, /* data_destroy */
   NULL, /* preprocess_text */
   HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT,
   NULL, /* decompose */
   NULL, /* compose */
   setup_masks_sea,
   HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE,
   false, /* fallback_position */
 };

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gfx/harfbuzz/src/hb-ot-shape-complex-sea.cc@925c144e1f1f (annotated)

gfx/harfbuzz/src/hb-ot-shape-complex-sea.cc