Fri Jul 25 23:07:06 2003  Owen Taylor  <otaylor@redhat.com>
 
        Update of GPOS and GSUB support to OpenType 1.3
        (From FreeType, Werner Lemberg, 2001-08-08)
 
        * pango/opentype/ftxopen.h: Add RIGHT_TO_LEFT LookupFlag
 
        * pango/opentype/ftxgpos.c (GPOS_Instance): Add 'first'
        member to mark the beginning of a chain of cursive connections.
         
        * pango/opentype/ftxgpos.c (Do_String_Lookup): If the
        RIGHT_TO_FLAG flag is set, shift cursive chain up so
        last glyph is on the baseline.

Index: pango/opentype/ftxgpos.c
===================================================================
RCS file: /cvs/gnome/pango/pango/opentype/ftxgpos.c,v
retrieving revision 1.10
diff -u -p -r1.10 ftxgpos.c
--- pango/opentype/ftxgpos.c	16 Apr 2003 03:58:17 -0000	1.10
+++ pango/opentype/ftxgpos.c	26 Jul 2003 03:13:18 -0000
@@ -43,6 +43,8 @@
     FT_UShort        load_flags;  /* how the glyph should be loaded */
     FT_Bool          r2l;
 
+    FT_UShort        first;       /* the first glyph in a chain of
+                                     cursive connections           */
     FT_UShort        last;        /* the last valid glyph -- used
                                      with cursive positioning     */
     FT_Pos           anchor_x;    /* the coordinates of the anchor point */
@@ -2089,6 +2091,8 @@
       gpi->last = 0xFFFF;
     else
     {
+      if ( gpi->first == 0xFFFF )
+        gpi->first  = in->pos;
       gpi->last     = in->pos;
       gpi->anchor_x = exit_x;
       gpi->anchor_y = exit_y;
@@ -6119,10 +6133,13 @@
     FT_UShort*  properties = gpos->LookupList.Properties;
     FT_UShort*  p_in       = in->properties;
 
-    int      nesting_level = 0;
+    int       nesting_level = 0;
+    FT_UShort i;
+    FT_Pos    offset;
 
 
-    gpi->last = 0xFFFF;      /* no last valid glyph for cursive pos. */
+    gpi->first = 0xFFFF;
+    gpi->last  = 0xFFFF;     /* no last valid glyph for cursive pos. */
 
     in->pos = 0;
 
@@ -6151,6 +6158,22 @@
         gpi->last = 0xFFFF;
 
         error = TTO_Err_Not_Covered;
+      }
+
+      /* test whether we have to adjust the offsets for cursive connections */
+
+      if ( gpi->first != 0xFFFF && gpi->last == 0xFFFF &&
+           gpos->LookupList.Lookup[lookup_index].LookupFlag & RIGHT_TO_LEFT )
+      {
+        offset = out[in->pos].y_pos;
+
+        /* no horizontal offsets (for vertical writing direction)
+           supported yet                                          */
+
+        for ( i = gpi->first; i <= in->pos; i++ )
+          out[i].y_pos -= offset;
+
+        gpi->first = 0xFFFF;
       }
 
       if ( error == TTO_Err_Not_Covered )
Index: pango/opentype/ftxopen.h
===================================================================
RCS file: /cvs/gnome/pango/pango/opentype/ftxopen.h,v
retrieving revision 1.2
diff -u -p -r1.2 ftxopen.h
--- pango/opentype/ftxopen.h	6 Sep 2002 22:45:12 -0000	1.2
+++ pango/opentype/ftxopen.h	26 Jul 2003 03:13:18 -0000
@@ -155,9 +155,13 @@ extern "C" {
   typedef struct TTO_LookupList_  TTO_LookupList;
 
 
-/* Possible LookupFlag bit masks.  `IGNORE_SPECIAL_MARKS' comes from the
-   OpenType 1.2 specification.                                           */
+  /* Possible LookupFlag bit masks.  `IGNORE_SPECIAL_MARKS' comes from the
+     OpenType 1.2 specification; RIGHT_TO_LEFT has been (re)introduced in
+     OpenType 1.3 -- if set, the last glyph in a cursive attachment
+     sequence has to be positioned on the baseline -- regardless of the
+     writing direction.                                                    */
 
+#define RIGHT_TO_LEFT         0x0001
 #define IGNORE_BASE_GLYPHS    0x0002
 #define IGNORE_LIGATURES      0x0004
 #define IGNORE_MARKS          0x0008