Bug 431394 – Use pango_glyph_item_iter in more places

2008-08-06  Behdad Esfahbod  <behdad@gnome.org>

        Bug 431394 – Use pango_glyph_item_iter in more places

        * pango/glyphstring.c (pango_glyph_string_get_logical_widths):
        Use pango_glyph_item_iter for cluster iteration.

svn path=/trunk/; revision=2680

1 files changed, 34 insertions, 36 deletions

diff --git a/pango/glyphstring.c b/pango/glyphstring.c
index 75a008c4..42601d52 100644
--- a/pango/glyphstring.c
+++ b/pango/glyphstring.c
@@ -321,49 +321,47 @@ pango_glyph_string_get_logical_widths (PangoGlyphString *glyphs,
 				       int               embedding_level,
 				       int              *logical_widths)
 {
-  int i, j;
-  int last_cluster = 0;
-  int width = 0;
-  int last_cluster_width = 0;
-  const char *p = text;		/* Points to start of current cluster */
-
-  for (i=0; i<=glyphs->num_glyphs; i++)
+  /* Build a PangoGlyphItem so we can use PangoGlyphItemIter.
+   * This API should have been made to take a PangoGlyphItem... */
+  PangoItem item = {0, length, g_utf8_strlen (text, length),
+		    {NULL, NULL, NULL,
+		     embedding_level, PANGO_GRAVITY_AUTO, 0,
+		     PANGO_SCRIPT_UNKNOWN, NULL,
+		     NULL}};
+  PangoGlyphItem glyph_item = {&item, glyphs};
+  PangoGlyphItemIter iter;
+  gboolean has_cluster;
+  int dir;
+
+  dir = embedding_level % 2 == 0 ? +1 : -1;
+  for (has_cluster = pango_glyph_item_iter_init_start (&iter, &glyph_item, text);
+       has_cluster;
+       has_cluster = pango_glyph_item_iter_next_cluster (&iter))
     {
-      int glyph_index = (embedding_level % 2 == 0) ? i : glyphs->num_glyphs - i - 1;
+      int glyph_index, char_index, num_chars, cluster_width = 0, char_width;
 
-      /* If this glyph belongs to a new cluster, or we're at the end, find
-       * the start of the next cluster, and assign the widths for this cluster.
-       */
-      if (i == glyphs->num_glyphs || p != text + glyphs->log_clusters[glyph_index])
-	{
-	  int next_cluster = last_cluster;
+      for (glyph_index  = iter.start_glyph;
+	   glyph_index != iter.end_glyph;
+	   glyph_index += dir)
+        {
+	  cluster_width += glyphs->glyphs[glyph_index].geometry.width;
+	}
 
-	  if (i < glyphs->num_glyphs)
-	    {
-	      while (p < text + glyphs->log_clusters[glyph_index])
-		{
-		  next_cluster++;
-		  p = g_utf8_next_char (p);
-		}
-	    }
-	  else
+      num_chars = iter.end_char - iter.start_char;
+      if (num_chars) /* pedantic */
+        {
+	  char_width = cluster_width / num_chars;
+
+	  for (char_index = iter.start_char;
+	       char_index < iter.end_char;
+	       char_index++)
 	    {
-	      while (p < text + length)
-		{
-		  next_cluster++;
-		  p = g_utf8_next_char (p);
-		}
+	      logical_widths[char_index] = char_width;
 	    }
 
-	  for (j = last_cluster; j < next_cluster; j++)
-	    logical_widths[j] = (width - last_cluster_width) / (next_cluster - last_cluster);
-
-	  last_cluster = next_cluster;
-	  last_cluster_width = width;
+	  /* add any residues to the first char */
+	  logical_widths[iter.start_char] += cluster_width - (char_width * num_chars);
 	}
-
-      if (i < glyphs->num_glyphs)
-	width += glyphs->glyphs[glyph_index].geometry.width;
     }
 }