Introduction
============

Use the ttktheme this time use themes that have the png images. 

.. _comboarrow:

.. figure:: ../figures/08comboarrow_large.png
   :width: 160px
   :height: 240px
   :align: center

Enlarge an image such as comboarrow-n.png from the Ubuntu theme and see 
that the outer border is one pixel wide. There are highlights and shadows also 
one pixel wide. The corners are a simple angle construction. The most tricky 
part is probably the arrow, which has a dark grey outer part and a light grey 
inner part. Several lighter pixels used for antialiasing surround the arrow 
and the diagonal lines, exactly how these were produced will become clearer 
a little later.

Comparing this widget to others it becomes clear that many of the ttktheme 
widgets are made in a similar manner. They are all of a similar size there 
are no arcs, all lines are one pixel wide and diagonals are used  with 
antialiasing to give the impression of rounded corners.