Update harfbuzz-ng to 1a5a91dc0d8bf4b72a2f22dc6300b06ad7000b79.

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

 /*
- * Copyright (C) 2009,2010  Red Hat, Inc.
- * Copyright (C) 2010  Google, Inc.
+ * Copyright © 2009,2010  Red Hat, Inc.
+ * Copyright © 2010,2011  Google, Inc.
  *
  *  This is part of HarfBuzz, a text shaping library.
  *
  * Permission is hereby granted, without written agreement and without
  * license or royalty fees, to use, copy, modify, and distribute this
  * software and its documentation for any purpose, provided that the
  * above copyright notice and the following two paragraphs appear in
  * all copies of this software.
  *
  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  * DAMAGE.
  *
  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  *
  * Red Hat Author(s): Behdad Esfahbod
  * Google Author(s): Behdad Esfahbod
  */
 
 #include "hb-ot-shape-private.hh"
 #include "hb-ot-shape-complex-private.hh"
 
-HB_BEGIN_DECLS
+#include "hb-font-private.hh"
 
 
-/* XXX vertical */
-hb_tag_t default_features[] = {
+
+hb_tag_t common_features[] = {
+  HB_TAG('c','c','m','p'),
+  HB_TAG('l','o','c','l'),
+  HB_TAG('m','a','r','k'),
+  HB_TAG('m','k','m','k'),
+  HB_TAG('r','l','i','g'),
+};
+
+hb_tag_t horizontal_features[] = {
   HB_TAG('c','a','l','t'),
-  HB_TAG('c','c','m','p'),
   HB_TAG('c','l','i','g'),
-  HB_TAG('c','s','w','h'),
   HB_TAG('c','u','r','s'),
   HB_TAG('k','e','r','n'),
   HB_TAG('l','i','g','a'),
-  HB_TAG('l','o','c','l'),
-  HB_TAG('m','a','r','k'),
-  HB_TAG('m','k','m','k'),
-  HB_TAG('r','l','i','g')
+};
+
+/* Note:
+ * Technically speaking, vrt2 and vert are mutually exclusive.
+ * According to the spec, valt and vpal are also mutually exclusive.
+ * But we apply them all for now.
+ */
+hb_tag_t vertical_features[] = {
+  HB_TAG('v','a','l','t'),
+  HB_TAG('v','e','r','t'),
+  HB_TAG('v','k','r','n'),
+  HB_TAG('v','p','a','l'),
+  HB_TAG('v','r','t','2'),
 };
 
 static void
-hb_ot_shape_collect_features (hb_ot_shape_plan_t       *plan,
+hb_ot_shape_collect_features (hb_ot_shape_planner_t          *planner,
                               const hb_segment_properties_t  *props,
-                              const hb_feature_t       *user_features,
-                              unsigned int              num_user_features)
+                              const hb_feature_t             *user_features,
+                              unsigned int                    num_user_features)
 {
   switch (props->direction) {
     case HB_DIRECTION_LTR:
-      plan->map.add_bool_feature (HB_TAG ('l','t','r','a'));
-      plan->map.add_bool_feature (HB_TAG ('l','t','r','m'));
+      planner->map.add_bool_feature (HB_TAG ('l','t','r','a'));
+      planner->map.add_bool_feature (HB_TAG ('l','t','r','m'));
       break;
     case HB_DIRECTION_RTL:
-      plan->map.add_bool_feature (HB_TAG ('r','t','l','a'));
-      plan->map.add_bool_feature (HB_TAG ('r','t','l','m'), false);
+      planner->map.add_bool_feature (HB_TAG ('r','t','l','a'));
+      planner->map.add_bool_feature (HB_TAG ('r','t','l','m'), false);
       break;
     case HB_DIRECTION_TTB:
     case HB_DIRECTION_BTT:
+    case HB_DIRECTION_INVALID:
     default:
       break;
   }
 
-  for (unsigned int i = 0; i < ARRAY_LENGTH (default_features); i++)
-    plan->map.add_bool_feature (default_features[i]);
+#define ADD_FEATURES(array) \
+  HB_STMT_START { \
+    for (unsigned int i = 0; i < ARRAY_LENGTH (array); i++) \
+      planner->map.add_bool_feature (array[i]); \
+  } HB_STMT_END
 
-  hb_ot_shape_complex_collect_features (plan, props);
+  hb_ot_shape_complex_collect_features (planner->shaper, &planner->map, props);
+
+  ADD_FEATURES (common_features);
+
+  if (HB_DIRECTION_IS_HORIZONTAL (props->direction))
+    ADD_FEATURES (horizontal_features);
+  else
+    ADD_FEATURES (vertical_features);
+
+#undef ADD_FEATURES
 
   for (unsigned int i = 0; i < num_user_features; i++) {
     const hb_feature_t *feature = &user_features[i];
-    plan->map.add_feature (feature->tag, feature->value, (feature->start == 0 && feature->end == (unsigned int) -1));
+    planner->map.add_feature (feature->tag, feature->value, (feature->start == 0 && feature->end == (unsigned int) -1));
   }
 }
 
 
 static void
 hb_ot_shape_setup_masks (hb_ot_shape_context_t *c)
 {
   hb_mask_t global_mask = c->plan->map.get_global_mask ();
   c->buffer->reset_masks (global_mask);
 
-  hb_ot_shape_complex_setup_masks (c); /* BUFFER: Clobbers var2 */
+  hb_ot_shape_complex_setup_masks (c->plan->shaper, &c->plan->map, c->buffer);
 
   for (unsigned int i = 0; i < c->num_user_features; i++)
   {
     const hb_feature_t *feature = &c->user_features[i];
     if (!(feature->start == 0 && feature->end == (unsigned int)-1)) {
       unsigned int shift;
       hb_mask_t mask = c->plan->map.get_mask (feature->tag, &shift);
       c->buffer->set_masks (feature->value << shift, mask, feature->start, feature->end);
     }
   }
 }
 
 
-static void
-hb_ot_substitute_complex (hb_ot_shape_context_t *c)
-{
-  if (!hb_ot_layout_has_substitution (c->face))
-    return;
-
-  c->plan->map.substitute (c->face, c->buffer);
-
-  c->applied_substitute_complex = TRUE;
-  return;
-}
-
-static void
-hb_ot_position_complex (hb_ot_shape_context_t *c)
-{
-
-  if (!hb_ot_layout_has_positioning (c->face))
-    return;
-
-  c->plan->map.position (c->font, c->face, c->buffer);
-
-  hb_ot_layout_position_finish (c->buffer);
-
-  c->applied_position_complex = TRUE;
-  return;
-}
-
-
 /* Main shaper */
 
 /* Prepare */
 
-static inline hb_bool_t
-is_variation_selector (hb_codepoint_t unicode)
+void
+_hb_set_unicode_props (hb_buffer_t *buffer)
 {
-  return unlikely ((unicode >=  0x180B && unicode <=  0x180D) || /* MONGOLIAN FREE VARIATION SELECTOR ONE..THREE */
-                   (unicode >=  0xFE00 && unicode <=  0xFE0F) || /* VARIATION SELECTOR-1..16 */
-                   (unicode >= 0xE0100 && unicode <= 0xE01EF));  /* VARIATION SELECTOR-17..256 */
+  unsigned int count = buffer->len;
+  for (unsigned int i = 1; i < count; i++)
+    hb_glyph_info_set_unicode_props (&buffer->info[i], buffer->unicode);
 }
 
 static void
-hb_set_unicode_props (hb_ot_shape_context_t *c)
+hb_form_clusters (hb_buffer_t *buffer)
 {
-  hb_unicode_get_general_category_func_t get_general_category = c->buffer->unicode->v.get_general_category;
-  hb_unicode_get_combining_class_func_t get_combining_class = c->buffer->unicode->v.get_combining_class;
-  hb_glyph_info_t *info = c->buffer->info;
-
-  unsigned int count = c->buffer->len;
-  for (unsigned int i = 1; i < count; i++) {
-    info[i].general_category() = get_general_category (info[i].codepoint);
-    info[i].combining_class() = get_combining_class (info[i].codepoint);
-  }
+  unsigned int count = buffer->len;
+  for (unsigned int i = 1; i < count; i++)
+    if (FLAG (buffer->info[i].general_category()) &
+        (FLAG (HB_UNICODE_GENERAL_CATEGORY_SPACING_MARK) |
+         FLAG (HB_UNICODE_GENERAL_CATEGORY_ENCLOSING_MARK) |
+         FLAG (HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK)))
+      buffer->info[i].cluster = buffer->info[i - 1].cluster;
 }
 
 static void
-hb_form_clusters (hb_ot_shape_context_t *c)
+hb_ensure_native_direction (hb_buffer_t *buffer)
 {
-  unsigned int count = c->buffer->len;
-  for (unsigned int i = 1; i < count; i++)
-    if (c->buffer->info[i].general_category() == HB_CATEGORY_NON_SPACING_MARK)
-      c->buffer->info[i].cluster = c->buffer->info[i - 1].cluster;
-}
+  hb_direction_t direction = buffer->props.direction;
 
-static void
-hb_ensure_native_direction (hb_ot_shape_context_t *c)
-{
-  hb_direction_t direction = c->buffer->props.direction;
-
-  /* TODO vertical */
-  if (HB_DIRECTION_IS_HORIZONTAL (direction) &&
-      direction != _hb_script_get_horizontal_direction (c->buffer->props.script))
+  /* TODO vertical:
+   * The only BTT vertical script is Ogham, but it's not clear to me whether OpenType
+   * Ogham fonts are supposed to be implemented BTT or not.  Need to research that
+   * first. */
+  if ((HB_DIRECTION_IS_HORIZONTAL (direction) && direction != hb_script_get_horizontal_direction (buffer->props.script)) ||
+      (HB_DIRECTION_IS_VERTICAL   (direction) && direction != HB_DIRECTION_TTB))
   {
-    hb_buffer_reverse_clusters (c->buffer);
-    c->buffer->props.direction = HB_DIRECTION_REVERSE (c->buffer->props.direction);
+    hb_buffer_reverse_clusters (buffer);
+    buffer->props.direction = HB_DIRECTION_REVERSE (buffer->props.direction);
   }
 }
 
-static void
-hb_reset_glyph_infos (hb_ot_shape_context_t *c)
-{
-  unsigned int count = c->buffer->len;
-  for (unsigned int i = 0; i < count; i++)
-    c->buffer->info[i].var1.u32 = c->buffer->info[i].var2.u32 = 0;
-}
-
 
 /* Substitute */
 
 static void
 hb_mirror_chars (hb_ot_shape_context_t *c)
 {
-  hb_unicode_get_mirroring_func_t get_mirroring = c->buffer->unicode->v.get_mirroring;
+  hb_unicode_funcs_t *unicode = c->buffer->unicode;
 
   if (HB_DIRECTION_IS_FORWARD (c->target_direction))
     return;
 
   hb_mask_t rtlm_mask = c->plan->map.get_1_mask (HB_TAG ('r','t','l','m'));
 
   unsigned int count = c->buffer->len;
   for (unsigned int i = 0; i < count; i++) {
-    hb_codepoint_t codepoint = get_mirroring (c->buffer->info[i].codepoint);
+    hb_codepoint_t codepoint = hb_unicode_mirroring (unicode, c->buffer->info[i].codepoint);
     if (likely (codepoint == c->buffer->info[i].codepoint))
       c->buffer->info[i].mask |= rtlm_mask; /* XXX this should be moved to before setting user-feature masks */
     else
       c->buffer->info[i].codepoint = codepoint;
   }
 }
 
 static void
 hb_map_glyphs (hb_font_t    *font,
-               hb_face_t    *face,
                hb_buffer_t  *buffer)
 {
+  hb_codepoint_t glyph;
+
   if (unlikely (!buffer->len))
     return;
 
   buffer->clear_output ();
+
   unsigned int count = buffer->len - 1;
-  for (buffer->i = 0; buffer->i < count;) {
-    if (unlikely (is_variation_selector (buffer->info[buffer->i + 1].codepoint))) {
-      buffer->replace_glyph (hb_font_get_glyph (font, face, buffer->info[buffer->i].codepoint, buffer->info[buffer->i + 1].codepoint));
-      buffer->i++;
+  for (buffer->idx = 0; buffer->idx < count;) {
+    if (unlikely (is_variation_selector (buffer->info[buffer->idx + 1].codepoint))) {
+      hb_font_get_glyph (font, buffer->info[buffer->idx].codepoint, buffer->info[buffer->idx + 1].codepoint, &glyph);
+      buffer->replace_glyph (glyph);
+      buffer->skip_glyph ();
     } else {
-      buffer->replace_glyph (hb_font_get_glyph (font, face, buffer->info[buffer->i].codepoint, 0));
+      hb_font_get_glyph (font, buffer->info[buffer->idx].codepoint, 0, &glyph);
+      buffer->replace_glyph (glyph);
     }
   }
-  if (likely (buffer->i < buffer->len))
-    buffer->replace_glyph (hb_font_get_glyph (font, face, buffer->info[buffer->i].codepoint, 0));
-  buffer->swap ();
+  if (likely (buffer->idx < buffer->len)) {
+    hb_font_get_glyph (font, buffer->info[buffer->idx].codepoint, 0, &glyph);
+    buffer->replace_glyph (glyph);
+  }
+  buffer->swap_buffers ();
 }
 
 static void
 hb_substitute_default (hb_ot_shape_context_t *c)
 {
-  hb_map_glyphs (c->font, c->face, c->buffer);
+  hb_ot_layout_substitute_start (c->buffer);
+
+  hb_mirror_chars (c);
+
+  hb_map_glyphs (c->font, c->buffer);
 }
 
 static void
+hb_ot_substitute_complex (hb_ot_shape_context_t *c)
+{
+  if (hb_ot_layout_has_substitution (c->face)) {
+    c->plan->map.substitute (c->face, c->buffer);
+    c->applied_substitute_complex = TRUE;
+  }
+
+  hb_ot_layout_substitute_finish (c->buffer);
+
+  return;
+}
+
+static void
 hb_substitute_complex_fallback (hb_ot_shape_context_t *c HB_UNUSED)
 {
   /* TODO Arabic */
 }
 
 
 /* Position */
 
 static void
 hb_position_default (hb_ot_shape_context_t *c)
 {
-  hb_buffer_clear_positions (c->buffer);
+  hb_ot_layout_position_start (c->buffer);
 
   unsigned int count = c->buffer->len;
   for (unsigned int i = 0; i < count; i++) {
-    hb_font_get_glyph_advance (c->font, c->face, c->buffer->info[i].codepoint,
-                               &c->buffer->pos[i].x_advance,
-                               &c->buffer->pos[i].y_advance);
+    hb_font_get_glyph_advance_for_direction (c->font, c->buffer->info[i].codepoint,
+                                             c->buffer->props.direction,
+                                             &c->buffer->pos[i].x_advance,
+                                             &c->buffer->pos[i].y_advance);
+    hb_font_subtract_glyph_origin_for_direction (c->font, c->buffer->info[i].codepoint,
+                                                 c->buffer->props.direction,
+                                                 &c->buffer->pos[i].x_offset,
+                                                 &c->buffer->pos[i].y_offset);
   }
 }
 
 static void
+hb_ot_position_complex (hb_ot_shape_context_t *c)
+{
+
+  if (hb_ot_layout_has_positioning (c->face))
+  {
+    /* Change glyph origin to what GPOS expects, apply GPOS, change it back. */
+
+    unsigned int count = c->buffer->len;
+    for (unsigned int i = 0; i < count; i++) {
+      hb_font_add_glyph_origin_for_direction (c->font, c->buffer->info[i].codepoint,
+                                              HB_DIRECTION_LTR,
+                                              &c->buffer->pos[i].x_offset,
+                                              &c->buffer->pos[i].y_offset);
+    }
+
+    c->plan->map.position (c->font, c->buffer);
+
+    for (unsigned int i = 0; i < count; i++) {
+      hb_font_subtract_glyph_origin_for_direction (c->font, c->buffer->info[i].codepoint,
+                                                   HB_DIRECTION_LTR,
+                                                   &c->buffer->pos[i].x_offset,
+                                                   &c->buffer->pos[i].y_offset);
+    }
+
+    c->applied_position_complex = TRUE;
+  }
+
+  hb_ot_layout_position_finish (c->buffer);
+
+  return;
+}
+
+static void
 hb_position_complex_fallback (hb_ot_shape_context_t *c HB_UNUSED)
 {
   /* TODO Mark pos */
 }
 
 static void
 hb_truetype_kern (hb_ot_shape_context_t *c)
 {
   /* TODO Check for kern=0 */
   unsigned int count = c->buffer->len;
   for (unsigned int i = 1; i < count; i++) {
-    hb_position_t kern, kern1, kern2;
-    kern = hb_font_get_kerning (c->font, c->face, c->buffer->info[i - 1].codepoint, c->buffer->info[i].codepoint);
-    kern1 = kern >> 1;
-    kern2 = kern - kern1;
+    hb_position_t x_kern, y_kern, kern1, kern2;
+    hb_font_get_glyph_kerning_for_direction (c->font,
+                                             c->buffer->info[i - 1].codepoint, c->buffer->info[i].codepoint,
+                                             c->buffer->props.direction,
+                                             &x_kern, &y_kern);
+
+    kern1 = x_kern >> 1;
+    kern2 = x_kern - kern1;
     c->buffer->pos[i - 1].x_advance += kern1;
     c->buffer->pos[i].x_advance += kern2;
     c->buffer->pos[i].x_offset += kern2;
+
+    kern1 = y_kern >> 1;
+    kern2 = y_kern - kern1;
+    c->buffer->pos[i - 1].y_advance += kern1;
+    c->buffer->pos[i].y_advance += kern2;
+    c->buffer->pos[i].y_offset += kern2;
   }
 }
 
 static void
 hb_position_complex_fallback_visual (hb_ot_shape_context_t *c)
 {
   hb_truetype_kern (c);
 }
 
 
 /* Do it! */
 
 static void
 hb_ot_shape_execute_internal (hb_ot_shape_context_t *c)
 {
+  c->buffer->deallocate_var_all ();
+
   /* Save the original direction, we use it later. */
   c->target_direction = c->buffer->props.direction;
 
-  hb_reset_glyph_infos (c); /* BUFFER: Clear buffer var1 and var2 */
+  HB_BUFFER_ALLOCATE_VAR (c->buffer, general_category);
+  HB_BUFFER_ALLOCATE_VAR (c->buffer, combining_class);
 
-  hb_set_unicode_props (c); /* BUFFER: Set general_category and combining_class in var1 */
+  _hb_set_unicode_props (c->buffer); /* BUFFER: Set general_category and combining_class */
 
-  hb_ensure_native_direction (c);
+  hb_form_clusters (c->buffer);
 
-  hb_form_clusters (c);
+  hb_ensure_native_direction (c->buffer);
 
-  hb_ot_shape_setup_masks (c); /* BUFFER: Clobbers var2 */
+  _hb_ot_shape_normalize (c);
+
+  hb_ot_shape_setup_masks (c);
 
   /* SUBSTITUTE */
   {
-    /* Mirroring needs to see the original direction */
-    hb_mirror_chars (c);
-
     hb_substitute_default (c);
 
     hb_ot_substitute_complex (c);
 
     if (!c->applied_substitute_complex)
       hb_substitute_complex_fallback (c);
   }
 
   /* POSITION */
   {
     hb_position_default (c);
 
     hb_ot_position_complex (c);
 
     hb_bool_t position_fallback = !c->applied_position_complex;
     if (position_fallback)
       hb_position_complex_fallback (c);
 
     if (HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction))
       hb_buffer_reverse (c->buffer);
 
     if (position_fallback)
       hb_position_complex_fallback_visual (c);
   }
 
+  HB_BUFFER_DEALLOCATE_VAR (c->buffer, combining_class);
+  HB_BUFFER_DEALLOCATE_VAR (c->buffer, general_category);
+
   c->buffer->props.direction = c->target_direction;
+
+  c->buffer->deallocate_var_all ();
 }
 
-void
+static void
 hb_ot_shape_plan_internal (hb_ot_shape_plan_t       *plan,
                            hb_face_t                *face,
                            const hb_segment_properties_t  *props,
                            const hb_feature_t       *user_features,
                            unsigned int              num_user_features)
 {
-  plan->shaper = hb_ot_shape_complex_categorize (props);
+  hb_ot_shape_planner_t planner;
 
-  hb_ot_shape_collect_features (plan, props, user_features, num_user_features);
+  planner.shaper = hb_ot_shape_complex_categorize (props);
 
-  plan->map.compile (face, props);
+  hb_ot_shape_collect_features (&planner, props, user_features, num_user_features);
+
+  planner.compile (face, props, *plan);
 }
 
-void
+static void
 hb_ot_shape_execute (hb_ot_shape_plan_t *plan,
                      hb_font_t          *font,
-                     hb_face_t          *face,
                      hb_buffer_t        *buffer,
                      const hb_feature_t *user_features,
                      unsigned int        num_user_features)
 {
-  hb_ot_shape_context_t c = {plan, font, face, buffer, user_features, num_user_features};
+  hb_ot_shape_context_t c = {plan, font, font->face, buffer, user_features, num_user_features};
   hb_ot_shape_execute_internal (&c);
 }
 
-void
-hb_ot_shape (hb_font_t    *font,
-             hb_face_t    *face,
-             hb_buffer_t  *buffer,
-             const hb_feature_t *user_features,
-             unsigned int        num_user_features)
+hb_bool_t
+hb_ot_shape (hb_font_t          *font,
+             hb_buffer_t        *buffer,
+             const hb_feature_t *features,
+             unsigned int        num_features,
+             const char * const *shaper_options)
 {
   hb_ot_shape_plan_t plan;
 
-  hb_ot_shape_plan_internal (&plan, face, &buffer->props, user_features, num_user_features);
-  hb_ot_shape_execute (&plan, font, face, buffer, user_features, num_user_features);
+  buffer->guess_properties ();
+
+  hb_ot_shape_plan_internal (&plan, font->face, &buffer->props, features, num_features);
+  hb_ot_shape_execute (&plan, font, buffer, features, num_features);
+
+  return TRUE;
 }
 
 
-HB_END_DECLS