harfbuzz-ng roll

third_party/harfbuzz-ng/src/hb-font.cc

 /*
  * Copyright © 2009  Red Hat, Inc.
+ * Copyright © 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
  * 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-private.hh"
 
 #include "hb-ot-layout-private.hh"
 
 #include "hb-font-private.hh"
 #include "hb-blob.h"
 #include "hb-open-file-private.hh"
 #include "hb-ot-head-table.hh"
@@ skipping 10 matching lines @@
 
 static hb_bool_t
 hb_font_get_glyph_nil (hb_font_t *font,
                        void *font_data HB_UNUSED,
                        hb_codepoint_t unicode,
                        hb_codepoint_t variation_selector,
                        hb_codepoint_t *glyph,
                        void *user_data HB_UNUSED)
 {
   if (font->parent)
-    return hb_font_get_glyph (font->parent, unicode, variation_selector, glyph);
+    return font->parent->get_glyph (unicode, variation_selector, glyph);
 
   *glyph = 0;
   return false;
 }
 
 static hb_position_t
 hb_font_get_glyph_h_advance_nil (hb_font_t *font,
                                  void *font_data HB_UNUSED,
                                  hb_codepoint_t glyph,
                                  void *user_data HB_UNUSED)
 {
   if (font->parent)
-    return font->parent_scale_x_distance (hb_font_get_glyph_h_advance (font->parent, glyph));
+    return font->parent_scale_x_distance (font->parent->get_glyph_h_advance (glyph));
 
   return font->x_scale;
 }
 
 static hb_position_t
 hb_font_get_glyph_v_advance_nil (hb_font_t *font,
                                  void *font_data HB_UNUSED,
                                  hb_codepoint_t glyph,
                                  void *user_data HB_UNUSED)
 {
   if (font->parent)
-    return font->parent_scale_y_distance (hb_font_get_glyph_v_advance (font->parent, glyph));
+    return font->parent_scale_y_distance (font->parent->get_glyph_v_advance (glyph));
 
   return font->y_scale;
 }
 
 static hb_bool_t
 hb_font_get_glyph_h_origin_nil (hb_font_t *font,
                                 void *font_data HB_UNUSED,
                                 hb_codepoint_t glyph,
                                 hb_position_t *x,
                                 hb_position_t *y,
                                 void *user_data HB_UNUSED)
 {
   if (font->parent) {
-    hb_bool_t ret = hb_font_get_glyph_h_origin (font->parent, glyph, x, y);
+    hb_bool_t ret = font->parent->get_glyph_h_origin (glyph, x, y);
     if (ret)
       font->parent_scale_position (x, y);
     return ret;
   }
 
   *x = *y = 0;
   return false;
 }
 
 static hb_bool_t
 hb_font_get_glyph_v_origin_nil (hb_font_t *font,
                                 void *font_data HB_UNUSED,
                                 hb_codepoint_t glyph,
                                 hb_position_t *x,
                                 hb_position_t *y,
                                 void *user_data HB_UNUSED)
 {
   if (font->parent) {
-    hb_bool_t ret = hb_font_get_glyph_v_origin (font->parent, glyph, x, y);
+    hb_bool_t ret = font->parent->get_glyph_v_origin (glyph, x, y);
     if (ret)
       font->parent_scale_position (x, y);
     return ret;
   }
 
   *x = *y = 0;
   return false;
 }
 
 static hb_position_t
 hb_font_get_glyph_h_kerning_nil (hb_font_t *font,
                                  void *font_data HB_UNUSED,
                                  hb_codepoint_t left_glyph,
                                  hb_codepoint_t right_glyph,
                                  void *user_data HB_UNUSED)
 {
   if (font->parent)
-    return font->parent_scale_x_distance (hb_font_get_glyph_h_kerning (font->parent, left_glyph, right_glyph));
+    return font->parent_scale_x_distance (font->parent->get_glyph_h_kerning (left_glyph, right_glyph));
 
   return 0;
 }
 
 static hb_position_t
 hb_font_get_glyph_v_kerning_nil (hb_font_t *font,
                                  void *font_data HB_UNUSED,
                                  hb_codepoint_t top_glyph,
                                  hb_codepoint_t bottom_glyph,
                                  void *user_data HB_UNUSED)
 {
   if (font->parent)
-    return font->parent_scale_y_distance (hb_font_get_glyph_v_kerning (font->parent, top_glyph, bottom_glyph));
+    return font->parent_scale_y_distance (font->parent->get_glyph_v_kerning (top_glyph, bottom_glyph));
 
   return 0;
 }
 
 static hb_bool_t
 hb_font_get_glyph_extents_nil (hb_font_t *font,
                                void *font_data HB_UNUSED,
                                hb_codepoint_t glyph,
                                hb_glyph_extents_t *extents,
                                void *user_data HB_UNUSED)
 {
   if (font->parent) {
-    hb_bool_t ret = hb_font_get_glyph_extents (font->parent,
-                                               glyph,
-                                               extents);
+    hb_bool_t ret = font->parent->get_glyph_extents (glyph, extents);
     if (ret) {
       font->parent_scale_position (&extents->x_bearing, &extents->y_bearing);
       font->parent_scale_distance (&extents->width, &extents->height);
     }
     return ret;
   }
 
   memset (extents, 0, sizeof (*extents));
   return false;
 }
 
 static hb_bool_t
 hb_font_get_glyph_contour_point_nil (hb_font_t *font,
                                      void *font_data HB_UNUSED,
                                      hb_codepoint_t glyph,
                                      unsigned int point_index,
                                      hb_position_t *x,
                                      hb_position_t *y,
                                      void *user_data HB_UNUSED)
 {
   if (font->parent) {
-    hb_bool_t ret = hb_font_get_glyph_contour_point (font->parent, glyph, point_index, x, y);
+    hb_bool_t ret = font->parent->get_glyph_contour_point (glyph, point_index, x, y);
     if (ret)
       font->parent_scale_position (x, y);
     return ret;
   }
 
   *x = *y = 0;
   return false;
 }
 
 static hb_bool_t
 hb_font_get_glyph_name_nil (hb_font_t *font,
                             void *font_data HB_UNUSED,
                             hb_codepoint_t glyph,
                             char *name, unsigned int size,
                             void *user_data HB_UNUSED)
 {
   if (font->parent)
-    return hb_font_get_glyph_name (font->parent, glyph, name, size);
+    return font->parent->get_glyph_name (glyph, name, size);
 
-  snprintf (name, size, "gid%u", glyph);
+  if (size) *name = '\0';
   return false;
 }
 
 static hb_bool_t
 hb_font_get_glyph_from_name_nil (hb_font_t *font,
                                  void *font_data HB_UNUSED,
                                  const char *name, int len, /* -1 means nul-terminated */
                                  hb_codepoint_t *glyph,
                                  void *user_data HB_UNUSED)
 {
   if (font->parent)
-    return hb_font_get_glyph_from_name (font->parent, name, len, glyph);
+    return font->parent->get_glyph_from_name (name, len, glyph);
 
   *glyph = 0;
   return false;
 }
 
 
 static const hb_font_funcs_t _hb_font_funcs_nil = {
   HB_OBJECT_HEADER_STATIC,
 
   true, /* immutable */
@@ skipping 103 matching lines @@
     ffuncs->get.name = hb_font_get_##name##_nil;                         \
     ffuncs->user_data.name = NULL;                                       \
     ffuncs->destroy.name = NULL;                                         \
   }                                                                      \
 }
 
 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
 #undef HB_FONT_FUNC_IMPLEMENT
 
 
+/* Public getters */
+
 hb_bool_t
 hb_font_get_glyph (hb_font_t *font,
                    hb_codepoint_t unicode, hb_codepoint_t variation_selector,
                    hb_codepoint_t *glyph)
 {
-  *glyph = 0;
-  return font->klass->get.glyph (font, font->user_data,
-                                 unicode, variation_selector, glyph,
-                                 font->klass->user_data.glyph);
+  return font->get_glyph (unicode, variation_selector, glyph);
 }
 
 hb_position_t
 hb_font_get_glyph_h_advance (hb_font_t *font,
                              hb_codepoint_t glyph)
 {
-  return font->klass->get.glyph_h_advance (font, font->user_data,
-                                           glyph,
-                                           font->klass->user_data.glyph_h_advance);
+  return font->get_glyph_h_advance (glyph);
 }
 
 hb_position_t
 hb_font_get_glyph_v_advance (hb_font_t *font,
                              hb_codepoint_t glyph)
 {
-  return font->klass->get.glyph_v_advance (font, font->user_data,
-                                           glyph,
-                                           font->klass->user_data.glyph_v_advance);
+  return font->get_glyph_v_advance (glyph);
 }
 
 hb_bool_t
 hb_font_get_glyph_h_origin (hb_font_t *font,
                             hb_codepoint_t glyph,
                             hb_position_t *x, hb_position_t *y)
 {
-  *x = *y = 0;
-  return font->klass->get.glyph_h_origin (font, font->user_data,
-                                           glyph, x, y,
-                                           font->klass->user_data.glyph_h_origin);
+  return font->get_glyph_h_origin (glyph, x, y);
 }
 
 hb_bool_t
 hb_font_get_glyph_v_origin (hb_font_t *font,
                             hb_codepoint_t glyph,
                             hb_position_t *x, hb_position_t *y)
 {
-  *x = *y = 0;
-  return font->klass->get.glyph_v_origin (font, font->user_data,
-                                           glyph, x, y,
-                                           font->klass->user_data.glyph_v_origin);
+  return font->get_glyph_v_origin (glyph, x, y);
 }
 
 hb_position_t
 hb_font_get_glyph_h_kerning (hb_font_t *font,
                              hb_codepoint_t left_glyph, hb_codepoint_t right_glyph)
 {
-  return font->klass->get.glyph_h_kerning (font, font->user_data,
-                                           left_glyph, right_glyph,
-                                           font->klass->user_data.glyph_h_kerning);
+  return font->get_glyph_h_kerning (left_glyph, right_glyph);
 }
 
 hb_position_t
 hb_font_get_glyph_v_kerning (hb_font_t *font,
                              hb_codepoint_t left_glyph, hb_codepoint_t right_glyph)
 {
-  return font->klass->get.glyph_v_kerning (font, font->user_data,
-                                     left_glyph, right_glyph,
-                                     font->klass->user_data.glyph_v_kerning);
+  return font->get_glyph_v_kerning (left_glyph, right_glyph);
 }
 
 hb_bool_t
 hb_font_get_glyph_extents (hb_font_t *font,
                            hb_codepoint_t glyph,
                            hb_glyph_extents_t *extents)
 {
-  memset (extents, 0, sizeof (*extents));
-  return font->klass->get.glyph_extents (font, font->user_data,
-                                         glyph,
-                                         extents,
-                                         font->klass->user_data.glyph_extents);
+  return font->get_glyph_extents (glyph, extents);
 }
 
 hb_bool_t
 hb_font_get_glyph_contour_point (hb_font_t *font,
                                  hb_codepoint_t glyph, unsigned int point_index,
                                  hb_position_t *x, hb_position_t *y)
 {
-  *x = *y = 0;
-  return font->klass->get.glyph_contour_point (font, font->user_data,
-                                               glyph, point_index,
-                                               x, y,
-                                               font->klass->user_data.glyph_contour_point);
+  return font->get_glyph_contour_point (glyph, point_index, x, y);
 }
 
 hb_bool_t
 hb_font_get_glyph_name (hb_font_t *font,
                         hb_codepoint_t glyph,
                         char *name, unsigned int size)
 {
-  return font->klass->get.glyph_name (font, font->user_data,
-                                      glyph,
-                                      name, size,
-                                      font->klass->user_data.glyph_name);
+  return font->get_glyph_name (glyph, name, size);
 }
 
 hb_bool_t
 hb_font_get_glyph_from_name (hb_font_t *font,
                              const char *name, int len, /* -1 means nul-terminated */
                              hb_codepoint_t *glyph)
 {
-  return font->klass->get.glyph_from_name (font, font->user_data,
-                                           name, len,
-                                           glyph,
-                                           font->klass->user_data.glyph_from_name);
+  return font->get_glyph_from_name (name, len, glyph);
 }
 
 
 /* A bit higher-level, and with fallback */
 
 void
 hb_font_get_glyph_advance_for_direction (hb_font_t *font,
                                          hb_codepoint_t glyph,
                                          hb_direction_t direction,
                                          hb_position_t *x, hb_position_t *y)
 {
-  if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
-    *x = hb_font_get_glyph_h_advance (font, glyph);
-    *y = 0;
-  } else {
-    *x = 0;
-    *y = hb_font_get_glyph_v_advance (font, glyph);
-  }
+  return font->get_glyph_advance_for_direction (glyph, direction, x, y);
 }
 
-static void
-guess_v_origin_minus_h_origin (hb_font_t *font,
-                               hb_codepoint_t glyph,
-                               hb_position_t *x, hb_position_t *y)
-{
-  *x = hb_font_get_glyph_h_advance (font, glyph) / 2;
-
-  /* TODO use font_metics.ascent */
-  *y = font->y_scale;
-}
-
-
 void
 hb_font_get_glyph_origin_for_direction (hb_font_t *font,
                                         hb_codepoint_t glyph,
                                         hb_direction_t direction,
                                         hb_position_t *x, hb_position_t *y)
 {
-  if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
-    hb_bool_t ret = hb_font_get_glyph_h_origin (font, glyph, x, y);
-    if (!ret && (ret = hb_font_get_glyph_v_origin (font, glyph, x, y))) {
-      hb_position_t dx, dy;
-      guess_v_origin_minus_h_origin (font, glyph, &dx, &dy);
-      *x -= dx; *y -= dy;
-    }
-  } else {
-    hb_bool_t ret = hb_font_get_glyph_v_origin (font, glyph, x, y);
-    if (!ret && (ret = hb_font_get_glyph_h_origin (font, glyph, x, y))) {
-      hb_position_t dx, dy;
-      guess_v_origin_minus_h_origin (font, glyph, &dx, &dy);
-      *x += dx; *y += dy;
-    }
-  }
+  return font->get_glyph_origin_for_direction (glyph, direction, x, y);
 }
 
 void
 hb_font_add_glyph_origin_for_direction (hb_font_t *font,
                                         hb_codepoint_t glyph,
                                         hb_direction_t direction,
                                         hb_position_t *x, hb_position_t *y)
 {
-  hb_position_t origin_x, origin_y;
-
-  hb_font_get_glyph_origin_for_direction (font, glyph, direction, &origin_x, &origin_y);
-
-  *x += origin_x;
-  *y += origin_y;
+  return font->add_glyph_origin_for_direction (glyph, direction, x, y);
 }
 
 void
 hb_font_subtract_glyph_origin_for_direction (hb_font_t *font,
                                              hb_codepoint_t glyph,
                                              hb_direction_t direction,
                                              hb_position_t *x, hb_position_t *y)
 {
-  hb_position_t origin_x, origin_y;
-
-  hb_font_get_glyph_origin_for_direction (font, glyph, direction, &origin_x, &origin_y);
-
-  *x -= origin_x;
-  *y -= origin_y;
+  return font->subtract_glyph_origin_for_direction (glyph, direction, x, y);
 }
 
 void
 hb_font_get_glyph_kerning_for_direction (hb_font_t *font,
                                          hb_codepoint_t first_glyph, hb_codepoint_t second_glyph,
                                          hb_direction_t direction,
                                          hb_position_t *x, hb_position_t *y)
 {
-  if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
-    *x = hb_font_get_glyph_h_kerning (font, first_glyph, second_glyph);
-    *y = 0;
-  } else {
-    *x = 0;
-    *y = hb_font_get_glyph_v_kerning (font, first_glyph, second_glyph);
-  }
+  return font->get_glyph_kerning_for_direction (first_glyph, second_glyph, direction, x, y);
 }
 
 hb_bool_t
 hb_font_get_glyph_extents_for_origin (hb_font_t *font,
                                       hb_codepoint_t glyph,
                                       hb_direction_t direction,
                                       hb_glyph_extents_t *extents)
 {
-  hb_bool_t ret = hb_font_get_glyph_extents (font, glyph, extents);
-
-  if (ret)
-    hb_font_subtract_glyph_origin_for_direction (font, glyph, direction, &extents->x_bearing, &extents->y_bearing);
-
-  return ret;
+  return font->get_glyph_extents_for_origin (glyph, direction, extents);
 }
 
 hb_bool_t
 hb_font_get_glyph_contour_point_for_origin (hb_font_t *font,
                                             hb_codepoint_t glyph, unsigned int point_index,
                                             hb_direction_t direction,
                                             hb_position_t *x, hb_position_t *y)
 {
-  hb_bool_t ret = hb_font_get_glyph_contour_point (font, glyph, point_index, x, y);
+  return font->get_glyph_contour_point_for_origin (glyph, point_index, direction, x, y);
+}
 
-  if (ret)
-    hb_font_subtract_glyph_origin_for_direction (font, glyph, direction, x, y);
+/* Generates gidDDD if glyph has no name. */
+void
+hb_font_glyph_to_string (hb_font_t *font,
+                         hb_codepoint_t glyph,
+                         char *s, unsigned int size)
+{
+  font->glyph_to_string (glyph, s, size);
+}
 
-  return ret;
+/* Parses gidDDD and uniUUUU strings automatically. */
+hb_bool_t
+hb_font_glyph_from_string (hb_font_t *font,
+                           const char *s, int len, /* -1 means nul-terminated */
+                           hb_codepoint_t *glyph)
+{
+  return font->glyph_from_string (s, len, glyph);
 }
 
 
 /*
  * hb_face_t
  */
 
 static const hb_face_t _hb_face_nil = {
   HB_OBJECT_HEADER_STATIC,
 
   true, /* immutable */
 
-  NULL, /* reference_table */
+  NULL, /* reference_table_func */
   NULL, /* user_data */
   NULL, /* destroy */
 
-  NULL, /* ot_layout */
+  0,    /* index */
+  1000, /* upem */
 
-  0,    /* index */
-  1000  /* upem */
+  {
+#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_INVALID,
+#include "hb-shaper-list.hh"
+#undef HB_SHAPER_IMPLEMENT
+  },
+
+  NULL, /* shape_plans */
 };
 
 
 hb_face_t *
-hb_face_create_for_tables (hb_reference_table_func_t  reference_table,
+hb_face_create_for_tables (hb_reference_table_func_t  reference_table_func,
                            void                      *user_data,
                            hb_destroy_func_t          destroy)
 {
   hb_face_t *face;
 
-  if (!reference_table || !(face = hb_object_create<hb_face_t> ())) {
+  if (!reference_table_func || !(face = hb_object_create<hb_face_t> ())) {
     if (destroy)
       destroy (user_data);
     return hb_face_get_empty ();
   }
 
-  face->reference_table = reference_table;
+  face->reference_table_func = reference_table_func;
   face->user_data = user_data;
   face->destroy = destroy;
 
-  face->ot_layout = _hb_ot_layout_create (face);
-
   face->upem = 0;
 
   return face;
 }
 
 
-typedef struct _hb_face_for_data_closure_t {
+typedef struct hb_face_for_data_closure_t {
   hb_blob_t *blob;
   unsigned int  index;
 } hb_face_for_data_closure_t;
 
 static hb_face_for_data_closure_t *
 _hb_face_for_data_closure_create (hb_blob_t *blob, unsigned int index)
 {
   hb_face_for_data_closure_t *closure;
 
   closure = (hb_face_for_data_closure_t *) malloc (sizeof (hb_face_for_data_closure_t));
@@ skipping 14 matching lines @@
 }
 
 static hb_blob_t *
 _hb_face_for_data_reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
 {
   hb_face_for_data_closure_t *data = (hb_face_for_data_closure_t *) user_data;
 
   if (tag == HB_TAG_NONE)
     return hb_blob_reference (data->blob);
 
-  const OpenTypeFontFile &ot_file = *Sanitizer<OpenTypeFontFile>::lock_instance (data->blob);
-  const OpenTypeFontFace &ot_face = ot_file.get_face (data->index);
+  const OT::OpenTypeFontFile &ot_file = *OT::Sanitizer<OT::OpenTypeFontFile>::lock_instance (data->blob);
+  const OT::OpenTypeFontFace &ot_face = ot_file.get_face (data->index);
 
-  const OpenTypeTable &table = ot_face.get_table_by_tag (tag);
+  const OT::OpenTypeTable &table = ot_face.get_table_by_tag (tag);
 
   hb_blob_t *blob = hb_blob_create_sub_blob (data->blob, table.offset, table.length);
 
   return blob;
 }
 
 hb_face_t *
 hb_face_create (hb_blob_t    *blob,
                 unsigned int  index)
 {
   hb_face_t *face;
 
   if (unlikely (!blob || !hb_blob_get_length (blob)))
     return hb_face_get_empty ();
 
-  hb_face_for_data_closure_t *closure = _hb_face_for_data_closure_create (Sanitizer<OpenTypeFontFile>::sanitize (hb_blob_reference (blob)), index);
+  hb_face_for_data_closure_t *closure = _hb_face_for_data_closure_create (OT::Sanitizer<OT::OpenTypeFontFile>::sanitize (hb_blob_reference (blob)), index);
 
   if (unlikely (!closure))
     return hb_face_get_empty ();
 
   face = hb_face_create_for_tables (_hb_face_for_data_reference_table,
                                     closure,
                                     (hb_destroy_func_t) _hb_face_for_data_closure_destroy);
 
   hb_face_set_index (face, index);
 
@@ skipping 11 matching lines @@
 hb_face_reference (hb_face_t *face)
 {
   return hb_object_reference (face);
 }
 
 void
 hb_face_destroy (hb_face_t *face)
 {
   if (!hb_object_destroy (face)) return;
 
-  _hb_ot_layout_destroy (face->ot_layout);
+  for (hb_face_t::plan_node_t *node = face->shape_plans; node; )
+  {
+    hb_face_t::plan_node_t *next = node->next;
+    hb_shape_plan_destroy (node->shape_plan);
+    free (node);
+    node = next;
+  }
+
+#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_DESTROY(shaper, face);
+#include "hb-shaper-list.hh"
+#undef HB_SHAPER_IMPLEMENT
 
   if (face->destroy)
     face->destroy (face->user_data);
 
   free (face);
 }
 
 hb_bool_t
 hb_face_set_user_data (hb_face_t          *face,
                        hb_user_data_key_t *key,
@@ skipping 24 matching lines @@
 hb_face_is_immutable (hb_face_t *face)
 {
   return face->immutable;
 }
 
 
 hb_blob_t *
 hb_face_reference_table (hb_face_t *face,
                          hb_tag_t   tag)
 {
-  hb_blob_t *blob;
-
-  if (unlikely (!face || !face->reference_table))
-    return hb_blob_get_empty ();
-
-  blob = face->reference_table (face, tag, face->user_data);
-  if (unlikely (!blob))
-    return hb_blob_get_empty ();
-
-  return blob;
+  return face->reference_table (tag);
 }
 
 hb_blob_t *
 hb_face_reference_blob (hb_face_t *face)
 {
-  return hb_face_reference_table (face, HB_TAG_NONE);
+  return face->reference_table (HB_TAG_NONE);
 }
 
 void
 hb_face_set_index (hb_face_t    *face,
                    unsigned int  index)
 {
   if (hb_object_is_inert (face))
     return;
 
   face->index = index;
@@ skipping 11 matching lines @@
 {
   if (hb_object_is_inert (face))
     return;
 
   face->upem = upem;
 }
 
 unsigned int
 hb_face_get_upem (hb_face_t *face)
 {
-  if (unlikely (!face->upem)) {
-    hb_blob_t *head_blob = Sanitizer<head>::sanitize (hb_face_reference_table (face, HB_OT_TAG_head));
-    const head *head_table = Sanitizer<head>::lock_instance (head_blob);
-    face->upem = head_table->get_upem ();
-    hb_blob_destroy (head_blob);
-  }
-  return face->upem;
+  return face->get_upem ();
 }
 
 
+void
+hb_face_t::load_upem (void) const
+{
+  hb_blob_t *head_blob = OT::Sanitizer<OT::head>::sanitize (reference_table (HB_OT_TAG_head));
+  const OT::head *head_table = OT::Sanitizer<OT::head>::lock_instance (head_blob);
+  upem = head_table->get_upem ();
+  hb_blob_destroy (head_blob);
+}
+
+
 /*
  * hb_font_t
  */
 
 hb_font_t *
 hb_font_create (hb_face_t *face)
 {
   hb_font_t *font;
 
   if (unlikely (!face))
@@ skipping 44 matching lines @@
     const_cast<hb_face_t *> (&_hb_face_nil),
 
     0, /* x_scale */
     0, /* y_scale */
 
     0, /* x_ppem */
     0, /* y_ppem */
 
     const_cast<hb_font_funcs_t *> (&_hb_font_funcs_nil), /* klass */
     NULL, /* user_data */
-    NULL  /* destroy */
+    NULL, /* destroy */
+
+    {
+#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_INVALID,
+#include "hb-shaper-list.hh"
+#undef HB_SHAPER_IMPLEMENT
+    }
   };
 
   return const_cast<hb_font_t *> (&_hb_font_nil);
 }
 
 hb_font_t *
 hb_font_reference (hb_font_t *font)
 {
   return hb_object_reference (font);
 }
 
 void
 hb_font_destroy (hb_font_t *font)
 {
   if (!hb_object_destroy (font)) return;
 
+#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_DESTROY(shaper, font);
+#include "hb-shaper-list.hh"
+#undef HB_SHAPER_IMPLEMENT
+
+  if (font->destroy)
+    font->destroy (font->user_data);
+
   hb_font_destroy (font->parent);
   hb_face_destroy (font->face);
   hb_font_funcs_destroy (font->klass);
-  if (font->destroy)
-    font->destroy (font->user_data);
 
   free (font);
 }
 
 hb_bool_t
 hb_font_set_user_data (hb_font_t          *font,
                        hb_user_data_key_t *key,
                        void *              data,
                        hb_destroy_func_t   destroy,
                        hb_bool_t           replace)
@@ skipping 115 matching lines @@
 }
 
 void
 hb_font_get_ppem (hb_font_t *font,
                   unsigned int *x_ppem,
                   unsigned int *y_ppem)
 {
   if (x_ppem) *x_ppem = font->x_ppem;
   if (y_ppem) *y_ppem = font->y_ppem;
 }
-
-