Merge changes from XeTeX repository

git-svn-id: svn://tug.org/texlive/trunk@26159 c570f23f-e606-0410-a88d-b1316a301751

2 files changed, 54 insertions, 22 deletions

diff --git a/Build/source/texk/web2c/xetexdir/ChangeLog b/Build/source/texk/web2c/xetexdir/ChangeLog
index d3fe3d5afab..68c577b0f5d 100644
--- a/Build/source/texk/web2c/xetexdir/ChangeLog
+++ b/Build/source/texk/web2c/xetexdir/ChangeLog
@@ -1,3 +1,7 @@
+2012-04-30  Khaled Hosny  <khaledhosny@eglug.org>
+
+	* xetex.ch: Merge changes from XeTeX repository.
+
 2012-04-24  Khaled Hosny  <khaledhosny@eglug.org>
 
 	* xetex.ch: Merge changes from XeTeX repository.
diff --git a/Build/source/texk/web2c/xetexdir/xetex.ch b/Build/source/texk/web2c/xetexdir/xetex.ch
index ddf6b5a5a6d..d90c3fd5a5b 100644
--- a/Build/source/texk/web2c/xetexdir/xetex.ch
+++ b/Build/source/texk/web2c/xetexdir/xetex.ch
@@ -4140,7 +4140,7 @@ end;
 @d accent_noad=over_noad+1 {|type| of a noad for accented subformulas}
 @d fixed_acc=1 {|subtype| for non growing math accents}
 @d bottom_acc=2 {|subtype| for bottom math accents}
-@d is_bottom_acc(#)==(subtype(#)=bottom_acc) or (subtype(#)=bottom_acc+fixed_acc)
+@d is_bottom_acc(#)==((subtype(#)=bottom_acc) or (subtype(#)=bottom_acc+fixed_acc))
 @z
 
 @x
@@ -4715,7 +4715,42 @@ if char_exists(cur_i) then
   x:=clean_box(nucleus(q),cramped_style(cur_style)); w:=width(x); h:=height(x);
   @<Switch to a larger accent if available and appropriate@>;
   if h<x_height(f) then delta:=h@+else delta:=x_height(f);
+  if (math_type(supscr(q))<>empty)or(math_type(subscr(q))<>empty) then
+    if math_type(nucleus(q))=math_char then
+      @<Swap the subscript and superscript into box |x|@>;
+  y:=char_box(f,c);
+  shift_amount(y):=s+half(w-width(y));
+  width(y):=0; p:=new_kern(-delta); link(p):=x; link(y):=p;
+  y:=vpack(y,natural); width(y):=width(x);
+  if height(y)<h then @<Make the height of box |y| equal to |h|@>;
+  info(nucleus(q)):=y;
+  math_type(nucleus(q)):=sub_box;
+  end;
+end;
 @y
+function compute_ot_math_accent_pos(@!p:pointer):scaled;
+var
+  @!q,@!r:pointer;
+  @!s,@!g:scaled;
+begin
+  if (math_type(nucleus(p))=math_char) then begin
+    fetch(nucleus(p));
+    q:=new_native_character(cur_f, qo(cur_c));
+    g:=get_native_glyph(q, 0);
+    s:=get_ot_math_accent_pos(cur_f, g);
+  end else begin
+    if (math_type(nucleus(p))=sub_mlist) then begin
+      r:=info(nucleus(p));
+      if (r<>null) and (type(r)=accent_noad) then
+        s:=compute_ot_math_accent_pos(r)
+      else
+        s:=@"7FFFFFFF;
+    end else
+      s:=@"7FFFFFFF;
+  end;
+  compute_ot_math_accent_pos:=s;
+end;
+
 procedure make_math_accent(@!q:pointer);
 label done,done1;
 var p,@!x,@!y:pointer; {temporary registers for box construction}
@@ -4723,16 +4758,16 @@ var p,@!x,@!y:pointer; {temporary registers for box construction}
 @!c,@!g:integer; {accent character}
 @!f:internal_font_number; {its font}
 @!i:four_quarters; {its |char_info|}
-@!s:scaled; {amount to skew the accent to the right}
+@!s,@!sa:scaled; {amount to skew the accent to the right}
 @!h:scaled; {height of character being accented}
 @!delta:scaled; {space to remove between accent and accentee}
-@!w,@!wa,@!w2:scaled; {width of the accentee, not including sub/superscripts}
+@!w,@!w2:scaled; {width of the accentee, not including sub/superscripts}
 @!ot_assembly_ptr:void_pointer;
 begin fetch(accent_chr(q));
 x:=null;
 if is_native_font(cur_f) then
   begin c:=cur_c; f:=cur_f;
-  s:=0; {@@<Compute the amount of skew@@>;}
+  if not is_bottom_acc(q) then s:=compute_ot_math_accent_pos(q);
   x:=clean_box(nucleus(q),cramped_style(cur_style)); w:=width(x); h:=height(x);
   end
 else if char_exists(cur_i) then
@@ -4747,15 +4782,9 @@ if x<>null then begin
     else if h<get_ot_math_constant(f, accentBaseHeight) then delta:=h@+else delta:=get_ot_math_constant(f, accentBaseHeight)
   else
     if h<x_height(f) then delta:=h@+else delta:=x_height(f);
-@z
-
-@x
-  y:=char_box(f,c);
-  shift_amount(y):=s+half(w-width(y));
-  width(y):=0; p:=new_kern(-delta); link(p):=x; link(y):=p;
-  y:=vpack(y,natural); width(y):=width(x);
-  if height(y)<h then @<Make the height of box |y| equal to |h|@>;
-@y
+  if (math_type(supscr(q))<>empty)or(math_type(subscr(q))<>empty) then
+    if math_type(nucleus(q))=math_char then
+      @<Swap the subscript and superscript into box |x|@>;
   y:=char_box(f,c);
   if is_native_font(f) then begin
     {turn the |native_word| node into a |native_glyph| one}
@@ -4769,15 +4798,10 @@ if x<>null then begin
     @<Switch to a larger native-font accent if available and appropriate@>;
 
     {determine horiz positioning}
-    wa:=get_ot_math_accent_pos(f,native_glyph(p));
-    if wa=@"7FFFFFFF then wa:=half(width(y));
-    p:=list_ptr(x);
-    if (p<>null) and is_glyph_node(p) and (math_type(nucleus(q))=math_char) then begin
-      w2:=get_ot_math_accent_pos(native_font(p), native_glyph(p));
-      if w2=@"7FFFFFFF then w:=half(w) else w:=w2;
-    end else
-      w:=half(w);
-    shift_amount(y):=s+w-wa;
+    sa:=get_ot_math_accent_pos(f,native_glyph(p));
+    if sa=@"7FFFFFFF then sa:=half(width(y));
+    if is_bottom_acc(q) or (s=@"7FFFFFFF) then s:=half(w);
+    shift_amount(y):=s-sa;
   end else
     shift_amount(y):=s+half(w-width(y));
   width(y):=0;
@@ -4788,6 +4812,10 @@ if x<>null then begin
     if height(y)<h then @<Make the height of box |y| equal to |h|@>;
   end;
   width(y):=width(x);
+  info(nucleus(q)):=y;
+  math_type(nucleus(q)):=sub_box;
+  end;
+end;
 @z
 
 @x