Roll HarfBuzz to 1.2.1

third_party/harfbuzz-ng/src/hb-ot-shape.cc

 /*
  * Copyright © 2009,2010  Red Hat, Inc.
  * Copyright © 2010,2011,2012  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
@@ skipping 127 matching lines @@
 }
 
 
 /*
  * shaper font data
  */
 
 struct hb_ot_shaper_font_data_t {};
 
 hb_ot_shaper_font_data_t *
-_hb_ot_shaper_font_data_create (hb_font_t *font)
+_hb_ot_shaper_font_data_create (hb_font_t *font HB_UNUSED)
 {
   return (hb_ot_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
 }
 
 void
 _hb_ot_shaper_font_data_destroy (hb_ot_shaper_font_data_t *data)
 {
 }
 
 
@@ skipping 101 matching lines @@
   buffer->swap_buffers ();
 }
 
 static void
 hb_form_clusters (hb_buffer_t *buffer)
 {
   if (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII) ||
       buffer->cluster_level != HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES)
     return;
 
-  /* Loop duplicated in hb_ensure_native_direction(). */
+  /* Loop duplicated in hb_ensure_native_direction(), and in _hb-coretext.cc */
   unsigned int base = 0;
   unsigned int count = buffer->len;
   hb_glyph_info_t *info = buffer->info;
   for (unsigned int i = 1; i < count; i++)
   {
-    if (likely (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i]))))
+    if (likely (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i])) &&
+                !_hb_glyph_info_is_joiner (&info[i])))
     {
       buffer->merge_clusters (base, i);
       base = i;
     }
   }
   buffer->merge_clusters (base, count);
 }
 
 static void
 hb_ensure_native_direction (hb_buffer_t *buffer)
@@ skipping 290 matching lines @@
 {
   hb_buffer_t *buffer = c->buffer;
 
   hb_ot_layout_substitute_start (c->font, buffer);
 
   if (!hb_ot_layout_has_glyph_classes (c->face))
     hb_synthesize_glyph_classes (c);
 
   c->plan->substitute (c->font, buffer);
 
-  hb_ot_layout_substitute_finish (c->font, buffer);
-
   return;
 }
 
 static inline void
 hb_ot_substitute (hb_ot_shape_context_t *c)
 {
   hb_ot_substitute_default (c);
 
   _hb_buffer_allocate_gsubgpos_vars (c->buffer);
 
@@ skipping 29 matching lines @@
     {
       if (adjust_offsets)
         adjust_mark_offsets (&buffer->pos[i]);
       zero_mark_width (&buffer->pos[i]);
     }
 }
 
 static inline void
 zero_mark_widths_by_gdef (hb_buffer_t *buffer, bool adjust_offsets)
 {
-  /* This one is a hack; Technically GDEF can mark ASCII glyphs as marks, but we don't listen. */
-  if (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII))
-    return;
-
   unsigned int count = buffer->len;
   hb_glyph_info_t *info = buffer->info;
   for (unsigned int i = 0; i < count; i++)
     if (_hb_glyph_info_is_mark (&info[i]))
     {
       if (adjust_offsets)
         adjust_mark_offsets (&buffer->pos[i]);
       zero_mark_width (&buffer->pos[i]);
     }
 }
@@ skipping 27 matching lines @@
                                         &pos[i].y_offset);
     }
   }
   if (c->buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_SPACE_FALLBACK)
     _hb_ot_shape_fallback_spaces (c->plan, c->font, c->buffer);
 }
 
 static inline bool
 hb_ot_position_complex (hb_ot_shape_context_t *c)
 {
+  hb_ot_layout_position_start (c->font, c->buffer);
+
   bool ret = false;
   unsigned int count = c->buffer->len;
   bool has_positioning = (bool) hb_ot_layout_has_positioning (c->face);
+
   /* If the font has no GPOS, AND, no fallback positioning will
    * happen, AND, direction is forward, then when zeroing mark
    * widths, we shift the mark with it, such that the mark
    * is positioned hanging over the previous glyph.  When
    * direction is backward we don't shift and it will end up
    * hanging over the next glyph after the final reordering.
    * If fallback positinoing happens or GPOS is present, we don't
    * care.
    */
   bool adjust_offsets_when_zeroing = !(has_positioning || c->plan->shaper->fallback_position ||
@@ skipping 54 matching lines @@
       zero_mark_widths_by_gdef (c->buffer, adjust_offsets_when_zeroing);
       break;
 
     default:
     case HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE:
     //case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_UNICODE_EARLY:
     case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY:
       break;
   }
 
+  /* Finishing off GPOS has to follow a certain order. */
+  hb_ot_layout_position_finish_advances (c->font, c->buffer);
+  hb_ot_zero_width_default_ignorables (c);
+  hb_ot_layout_position_finish_offsets (c->font, c->buffer);
+
   return ret;
 }
 
 static inline void
 hb_ot_position (hb_ot_shape_context_t *c)
 {
-  hb_ot_layout_position_start (c->font, c->buffer);
+  c->buffer->clear_positions ();
 
   hb_ot_position_default (c);
 
   hb_bool_t fallback = !hb_ot_position_complex (c);
 
-  hb_ot_zero_width_default_ignorables (c);
-
-  hb_ot_layout_position_finish (c->font, c->buffer);
-
   if (fallback && c->plan->shaper->fallback_position)
     _hb_ot_shape_fallback_position (c->plan, c->font, c->buffer);
 
   if (HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction))
     hb_buffer_reverse (c->buffer);
 
   /* Visual fallback goes here. */
 
   if (fallback)
     _hb_ot_shape_fallback_kern (c->plan, c->font, c->buffer);
@@ skipping 130 matching lines @@
   hb_set_t copy;
   copy.init ();
   do {
     copy.set (glyphs);
     for (hb_codepoint_t lookup_index = -1; hb_set_next (&lookups, &lookup_index);)
       hb_ot_layout_lookup_substitute_closure (font->face, lookup_index, glyphs);
   } while (!copy.is_equal (glyphs));
 
   hb_shape_plan_destroy (shape_plan);
 }