[ot-glyph] Redesign the API

src/hb-ot-glyph.cc

@@ -29,29 +29,134 @@
 #include "hb-ot.h"
 #include "hb-ot-glyf-table.hh"
 
-unsigned int
+struct hb_ot_glyph_path_t
-hb_ot_glyph_get_outline_path (hb_font_t                *font,
-			      hb_codepoint_t            glyph,
-			      unsigned int              start_offset,
-			      unsigned int             *points_count /* IN/OUT.  May be NULL. */,
-			      hb_ot_glyph_path_point_t *points       /* OUT.     May be NULL. */)
 {
-  unsigned int points_to_write = likely (points && points_count) ? *points_count : 0;
+  hb_object_header_t header;
-  if (likely (points_count)) *points_count = 0;
+
-  unsigned int all_points_count = 0;
+  const hb_position_t *coords;
+  unsigned int coords_count;
+
+  const uint8_t *commands;
+  unsigned int commands_count;
+
+  void *user_data;
+  hb_destroy_func_t destroy;
+};
+
+hb_ot_glyph_path_t *
+hb_ot_glyph_path_empty ()
+{
+  return const_cast<hb_ot_glyph_path_t *> (&Null (hb_ot_glyph_path_t));
+}
+
+hb_ot_glyph_path_t *
+hb_ot_glyph_create_path (hb_position_t     *coords,
+			 unsigned int       coords_count,
+			 uint8_t           *commands,
+			 unsigned int       commands_count,
+			 void              *user_data,
+			 hb_destroy_func_t  destroy)
+{
+  hb_ot_glyph_path_t *path;
+
+  if (!coords_count || !commands_count ||
+      !(path = hb_object_create<hb_ot_glyph_path_t> ()))
+  {
+    if (destroy)
+      destroy (user_data);
+    return hb_ot_glyph_path_empty ();
+  }
+
+  path->coords = coords;
+  path->coords_count =  coords_count;
+  path->commands = commands;
+  path->commands_count = commands_count;
+  path->user_data = user_data;
+  path->destroy = destroy;
+
+  return path;
+}
+
+const hb_position_t *
+hb_ot_glyph_path_get_coords (hb_ot_glyph_path_t *path, unsigned int *count)
+{
+  if (count) *count = path->coords_count;
+  return path->coords;
+}
+
+const uint8_t *
+hb_ot_glyph_path_get_commands (hb_ot_glyph_path_t *path, unsigned int *count)
+{
+  if (count) *count = path->commands_count;
+  return path->commands;
+}
+
+hb_ot_glyph_path_t *
+hb_ot_glyph_path_reference (hb_ot_glyph_path_t *path)
+{
+  return hb_object_reference (path);
+}
+
+void
+hb_ot_glyph_path_destroy (hb_ot_glyph_path_t *path)
+{
+  if (!hb_object_destroy (path)) return;
+}
+
+struct _hb_ot_glyph_path_vectors
+{
+  hb_vector_t<hb_position_t> *coords;
+  hb_vector_t<uint8_t> *commands;
+
+  bool init ()
+  {
+    coords = (hb_vector_t<hb_position_t> *) malloc (sizeof (hb_vector_t<hb_position_t>));
+    commands = (hb_vector_t<uint8_t> *) malloc (sizeof (hb_vector_t<uint8_t>));
+    if (unlikely (!coords || !commands))
+    {
+      free (coords);
+      free (commands);
+      return false;
+    }
+    coords->init ();
+    commands->init ();
+    return true;
+  }
+
+  void fini ()
+  {
+    coords->fini ();
+    commands->fini ();
+  }
+};
+
+static void
+_hb_ot_glyph_free_path_vectors (void *user_data)
+{
+  ((_hb_ot_glyph_path_vectors *) user_data)->fini ();
+  free (user_data);
+}
+
+hb_ot_glyph_path_t *
+hb_ot_glyph_create_path_from_font (hb_font_t *font, hb_codepoint_t glyph)
+{
+  _hb_ot_glyph_path_vectors *user_data = (_hb_ot_glyph_path_vectors *)
+					 malloc (sizeof (_hb_ot_glyph_path_vectors));
+  if (unlikely (!user_data->init ())) return hb_ot_glyph_path_empty ();
+
+  hb_vector_t<hb_position_t> &coords = *user_data->coords;
+  hb_vector_t<uint8_t> &commands = *user_data->commands;
   font->face->table.glyf->get_path (font, glyph,
 				    [&] (char cmd, float x, float y)
 				    {
-				      all_points_count++;
+				      if (cmd != ' ') commands.push (cmd);
-				      if (start_offset) { start_offset--; return; }
+				      if (cmd == 'Z') return;
-				      if (points_to_write)
+				      coords.push (font->em_scalef_x (x));
-				      {
+				      coords.push (font->em_scalef_y (y));
-					points[*points_count] = {cmd, font->em_scalef_x (x), font->em_scalef_y (y)};
-					*points_count += 1;
-					points_to_write--;
-				      }
 				    });
-  return all_points_count;
+
+  return hb_ot_glyph_create_path (coords.arrayZ, coords.length, commands.arrayZ, commands.length,
+				  user_data, (hb_destroy_func_t) _hb_ot_glyph_free_path_vectors);
 }
 
 #endif

src/hb-ot-glyph.h

@@ -33,19 +33,33 @@
 
 HB_BEGIN_DECLS
 
-typedef struct hb_ot_glyph_path_point_t
+typedef struct hb_ot_glyph_path_t hb_ot_glyph_path_t;
-{
-  char cmd;
-  hb_position_t x;
-  hb_position_t y;
-} hb_ot_glyph_path_point_t;
 
-HB_EXTERN unsigned int
+HB_EXTERN hb_ot_glyph_path_t *
-hb_ot_glyph_get_outline_path (hb_font_t                *font,
+hb_ot_glyph_path_empty ();
-			      hb_codepoint_t            glyph,
+
-			      unsigned int              start_offset,
+HB_EXTERN hb_ot_glyph_path_t *
-			      unsigned int             *points_count /* IN/OUT.  May be NULL. */,
+hb_ot_glyph_create_path (hb_position_t     *coords,
-			      hb_ot_glyph_path_point_t *points       /* OUT.     May be NULL. */);
+			 unsigned int       coords_count,
+			 uint8_t           *commands,
+			 unsigned int       commands_count,
+			 void              *user_data,
+			 hb_destroy_func_t  destroy);
+
+HB_EXTERN const hb_position_t *
+hb_ot_glyph_path_get_coords (hb_ot_glyph_path_t *path, unsigned int *count);
+
+HB_EXTERN const uint8_t *
+hb_ot_glyph_path_get_commands (hb_ot_glyph_path_t *path, unsigned int *count);
+
+HB_EXTERN hb_ot_glyph_path_t *
+hb_ot_glyph_path_reference (hb_ot_glyph_path_t *path);
+
+HB_EXTERN void
+hb_ot_glyph_path_destroy (hb_ot_glyph_path_t *path);
+
+HB_EXTERN hb_ot_glyph_path_t *
+hb_ot_glyph_create_path_from_font (hb_font_t *font, hb_codepoint_t glyph);
 
 HB_END_DECLS
 

src/test-ot-glyph.cc

@@ -55,26 +55,44 @@ main (int argc, char **argv)
     unsigned int glyph_count = hb_face_get_glyph_count (face);
     for (unsigned int gid = 0; gid < glyph_count; ++gid)
     {
-      hb_ot_glyph_path_point_t points[200];
+      hb_font_extents_t font_extents;
-      unsigned int points_len = 200;
+      hb_font_get_extents_for_direction (font, HB_DIRECTION_LTR, &font_extents);
-      hb_ot_glyph_get_outline_path (font, gid, 0, nullptr, nullptr); /* just to test it */
-      printf ("gid %d, points count: %d\n", gid, hb_ot_glyph_get_outline_path (font, gid, 0, &points_len, points));
       hb_glyph_extents_t extents = {0};
       hb_font_get_glyph_extents (font, gid, &extents);
       char name[100];
       sprintf (name, "%d.svg", gid);
       FILE *f = fopen (name, "wb");
-      int factor = 1;
-      if (extents.height < 0) factor = -1;
       fprintf (f, "<svg xmlns=\"http://www.w3.org/2000/svg\""
-		  " viewBox=\"0 0 %d %d\"><path d=\"", extents.width, extents.height * factor);
+		  " viewBox=\"%d %d %d %d\"><path d=\"",
-      for (unsigned i = 0; i < points_len; ++i)
+		  extents.x_bearing, 0,
+		  extents.x_bearing + extents.width, font_extents.ascender - font_extents.descender); //-extents.height);
+      hb_ot_glyph_path_t *path = hb_ot_glyph_create_path_from_font (font, gid);
+      unsigned int commands_count;
+      const uint8_t *commands = hb_ot_glyph_path_get_commands (path, &commands_count);
+      unsigned int coords_count;
+      const hb_position_t *coords = hb_ot_glyph_path_get_coords (path, &coords_count);
+      for (unsigned i = 0, j = 0; i < commands_count && j < coords_count; ++i)
       {
-	if (points[i].cmd == 'Z') fprintf (f, "Z");
+	fprintf (f, "%c", commands[i]);
-	else fprintf (f, "%c%d,%d", points[i].cmd, points[i].x, (points[i].y + extents.height) * factor);
+	if (commands[i] == 'Z') continue;
+	fprintf (f, "%d,%d", coords[j], font_extents.ascender - coords[j + 1]); //extents.y_bearing - points[i].y);
+	j += 2;
+	if (commands[i] == 'Q')
+	{
+	  fprintf (f, " %d,%d", coords[j], font_extents.ascender - coords[j + 1]); //extents.y_bearing - points[i].y);
+	  j += 2;
+	}
+	if (commands[i] == 'C')
+	{
+	  fprintf (f, " %d,%d", coords[j], font_extents.ascender - coords[j + 1]); //extents.y_bearing - points[i].y);
+	  j += 2;
+	  fprintf (f, " %d,%d", coords[j], font_extents.ascender - coords[j + 1]); //extents.y_bearing - points[i].y);
+	  j += 2;
+	}
       }
       fprintf (f, "\"/></svg>");
       fclose (f);
+      hb_ot_glyph_path_destroy (path);
     }
     hb_font_destroy (font);
     hb_face_destroy (face);