new file mode 100644

@@ -0,0 +1,6 @@

+digraph G {

+    Foo[label=<<B>Hello</B><SUP>world</SUP>>]

+    Bar[label=<<U><I><S>Hel</S>lo</I></U><SUB><B>world</B></SUB>>]

+

+    Foo->Bar

+}

@@ -56,6 +56,14 @@ class Pen:

         self.linewidth = 1.0

         self.fontsize = 14.0

         self.fontname = "Times-Roman"

+        self.bold = False

+        self.italic = False

+        self.underline = False

+        self.superscript = False

+        self.subscript = False

+        self.strikethrough = False

+        self.overline = False

+

         self.dash = ()

     def copy(self):

@@ -102,9 +110,9 @@ class TextShape(Shape):

         self.pen = pen.copy()

         self.x = x

         self.y = y

-        self.j = j

-        self.w = w

-        self.t = t

+        self.j = j  # Centering

+        self.w = w  # width

+        self.t = t  # text

     def draw(self, cr, highlight=False):

@@ -129,8 +137,28 @@ class TextShape(Shape):

             # set font

             font = pango.FontDescription()

+            attrs = pango.AttrList()

+

+            # set font attributes

+            if self.pen.bold:

+                font.set_weight(pango.WEIGHT_BOLD)

+            if self.pen.italic:

+                font.set_style(pango.STYLE_ITALIC)

+            if self.pen.underline:

+                underline = pango.AttrUnderline(pango.UNDERLINE_SINGLE, 0, len(self.t))

+                attrs.insert(underline)

+            if self.pen.strikethrough:

+                st =  pango.AttrStrikethrough(True, 0, len(self.t))

+                attrs.insert(st)

+

+            layout.set_attributes(attrs)

+

+            fontsize = self.pen.fontsize

+            if self.pen.superscript or self.pen.subscript:

+                fontsize /= 1.5

+

             font.set_family(self.pen.fontname)

-            font.set_absolute_size(self.pen.fontsize*pango.SCALE)

+            font.set_absolute_size(fontsize*pango.SCALE)

             layout.set_font_description(font)

             # set text

@@ -146,6 +174,7 @@ class TextShape(Shape):

         width, height = layout.get_size()

         width = float(width)/pango.SCALE

         height = float(height)/pango.SCALE

+

         # we know the width that dot thinks this text should have

         # we do not necessarily have a font with the same metrics

         # scale it so that the text fits inside its box

@@ -166,7 +195,10 @@ class TextShape(Shape):

         else:

             assert 0

-        y = self.y - height + descent

+        if self.pen.superscript:

+            y = self.y - 1.5*height

+        else:

+            y = self.y - height + descent

         cr.move_to(x, y)

@@ -718,9 +750,15 @@ class XDotAttrParser:

         self.pen.fontname = name

     def handle_font_characteristics(self, flags):

-        # TODO

-        if flags != 0:

-            sys.stderr.write("warning: font characteristics not supported yet\n")

+        self.pen.bold = bool(flags & BOLD)

+        self.pen.italic = bool(flags & ITALIC)

+        self.pen.underline = bool(flags & UNDERLINE)

+        self.pen.superscript = bool(flags & SUPERSCRIPT)

+        self.pen.subscript = bool(flags & SUBSCRIPT)

+        self.pen.strikethrough = bool(flags & STRIKE_THROUGH)

+        self.pen.overline = bool(flags & OVERLINE)

+        if self.pen.overline:

+            sys.stderr.write('warning: overlined text not supported yet\n')

     def handle_text(self, x, y, j, w, t):

         self.shapes.append(TextShape(self.pen, x, y, j, w, t))