First draft of highlevel driver. It currently only handles a paragraph as

Wed Mar  8 13:34:57 2000  Owen Taylor  <otaylor@redhat.com>

	* libpango/pango-layout.[ch]: First draft of highlevel
	driver. It currently only handles a paragraph as a list
	of lines, but it is probably necessary to make it handle
	2D layout for a paragraph as well

	* examples/viewer.c: Move over to new layout driver
	(much of the code moved into pango-layout.c)

	* libpango/glyphs.c libpango/pango-glyphs.h: Fixes to get_extents(),
	add pango_glyph_string_get_logical_widths.

	* libpango/pango-itemize.c: Handle 0-length text properly.

	* libpango/pangox.c: When loading particular sized fonts,
	use the original XLFD, since XFree86 doesn't handle wildcards
	in aliases properly.

	* libpango/pangox.[ch] (pango_x_render_layout_line): Add function
	to render an entire PangoLayoutLine.

	* libpango/reorder-items.c: Add a note to the effect
	that pango_reorder_items() is basically replaced by a
	similar function in PangoLayout.

Wed Mar  8 10:58:56 2000  Owen Taylor  <otaylor@redhat.com>

	* modules/arabic/arconv.c (shapecount): Fix from Karl
	Koehler to joining behavior.

	* modules/Makefile.am modules/arabic/*: Added arabic
	shaper from Karl Koehler <koehler@or.uni-bonn.de>

	* modules/basic/tables-{small,big}.i: Remove arabic
	from the ranges that the basic shaper marks as "exact".

	* examples/HELLO.utf8: Partially alphabetize, add arabic.

1 files changed, 69 insertions, 4 deletions

diff --git a/pango/glyphstring.c b/pango/glyphstring.c
index b29efe09..d3030e39 100644
--- a/pango/glyphstring.c
+++ b/pango/glyphstring.c
@@ -22,6 +22,7 @@
 #include <glib.h>
 #include <pango-glyph.h>
 #include <pango-font.h>
+#include <unicode.h>
 
 /**
  * pango_glyph_string_new:
@@ -151,12 +152,12 @@ pango_glyph_string_extents (PangoGlyphString *glyphs,
 	    {
 	      new_pos = MIN (ink_rect->x, x_pos + glyph_ink.x + geometry->x_offset);
 	      ink_rect->width = MAX (ink_rect->x + ink_rect->width,
-				     x_pos + glyph_ink.x + glyph_ink.width + geometry->x_offset) - ink_rect->x;
+				     x_pos + glyph_ink.x + glyph_ink.width + geometry->x_offset) - new_pos;
 	      ink_rect->x = new_pos;
 
 	      new_pos = MIN (ink_rect->y, glyph_ink.y + geometry->y_offset);
 	      ink_rect->height = MAX (ink_rect->y + ink_rect->height,
-				      glyph_ink.y + glyph_ink.height + geometry->y_offset) - ink_rect->y;
+				      glyph_ink.y + glyph_ink.height + geometry->y_offset) - new_pos;
 	      ink_rect->y = new_pos;
 	    }
 
@@ -164,12 +165,12 @@ pango_glyph_string_extents (PangoGlyphString *glyphs,
 	    {
 	      new_pos = MIN (logical_rect->x, x_pos + glyph_logical.x + geometry->x_offset);
 	      logical_rect->width = MAX (logical_rect->x + logical_rect->width,
-				     x_pos + glyph_logical.x + glyph_logical.width + geometry->x_offset) - logical_rect->x;
+				     x_pos + glyph_logical.x + glyph_logical.width + geometry->x_offset) - new_pos;
 	      logical_rect->x = new_pos;
 
 	      new_pos = MIN (logical_rect->y, glyph_logical.y + geometry->y_offset);
 	      logical_rect->height = MAX (logical_rect->y + logical_rect->height,
-				      glyph_logical.y + glyph_logical.height + geometry->y_offset) - logical_rect->y;
+				      glyph_logical.y + glyph_logical.height + geometry->y_offset) - new_pos;
 	      logical_rect->y = new_pos;
 	    }
 	}
@@ -178,3 +179,67 @@ pango_glyph_string_extents (PangoGlyphString *glyphs,
     }
 }
 
+/**
+ * pango_glyph_string_get_logical_widths:
+ * @glyphs: a #PangoGlyphString
+ * @text: the text corresponding to the glyphs
+ * @length: the length of @text, in bytes
+ * @embedding_level: the embedding level of the string
+ * @logical_widths: an array whose length is unicode_strlen (text, length)
+ *                  to be filled in with the resulting character widths.
+ *
+ * Given a #PangoGlyphString resulting from pango_shape() and the corresponding
+ * text, determine the screen width corresponding to each character. When
+ * multiple characters compose a single cluster, the width of the entire
+ * cluster is divided equally among the characters.
+ **/
+void
+pango_glyph_string_get_logical_widths (PangoGlyphString *glyphs,
+				       char             *text,
+				       int               length,
+				       int               embedding_level,
+				       int              *logical_widths)
+{
+  int i, j;
+  int last_cluster = 0;
+  int width = 0;
+  int last_cluster_width = 0;
+  char *p = text;
+  
+  for (i=0; i<=glyphs->num_glyphs; i++)
+    {
+      int glyph_index = (embedding_level % 2 == 0) ? i : glyphs->num_glyphs - i - 1;
+      
+      if (i == glyphs->num_glyphs || p != text + glyphs->log_clusters[glyph_index])
+	{
+	  int next_cluster = last_cluster;
+	  
+	  if (glyph_index < glyphs->num_glyphs)
+	    {
+	      while (p < text + glyphs->log_clusters[glyph_index])
+		{
+		  next_cluster++;
+		  p = unicode_next_utf8 (p);
+		}
+	    }
+	  else
+	    {
+	      while (p < text + length)
+		{
+		  next_cluster++;
+		  p = unicode_next_utf8 (p);
+		}
+	    }
+	  
+	  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;
+	}
+      
+      if (i < glyphs->num_glyphs)
+	width += glyphs->glyphs[i].geometry.width;
+    }
+}
+