@@ -887,7 +887,7 @@ class DotWidget(gtk.DrawingArea):

     def set_dotcode(self, dotcode, filename='<stdin>'):

         p = subprocess.Popen(

-            ['dot', '-Txdot'],

+            [options.filter, '-Txdot'],

             stdin=subprocess.PIPE,

             stdout=subprocess.PIPE,

             shell=False,

@@ -1232,10 +1232,16 @@ class DotWindow(gtk.Window):

 def main():

     import optparse

+    global options

     parser = optparse.OptionParser(

-        usage="\n\t%prog [file]",

-        version="%%prog %s" % __version__)

+        usage='\n\t%prog [file]',

+        version='%%prog %s' % __version__)

+    parser.add_option(

+        '-f', '--filter',

+        type='choice', choices=('dot', 'neato', 'twopi', 'circo', 'fdp'),

+        dest='filter', default='dot',

+        help='graphviz filter: dot, neato, twopi, circo, or fdp [default: %default]')

     (options, args) = parser.parse_args(sys.argv[1:])

     if len(args) > 1: