Gaphas is a diagramming widget for GTK+ written in Python. Gaphas is a MVC canvas that uses Cairo_ for rendering. One of the nicer things
of this widget is that the user (model) is not bothered with bounding box
calculations: this is all done through Cairo.

Some more features:

- Each item has it's own separate coordinate space (easy when items are
rotated).
- Items on the canvas can be connected to each other. Connections are
maintained by a linear constraint solver.
- Multiple views on one Canvas.
- What is drawn is determined by Painters. Multiple painters can be used and
painters can be stacked.
- User interaction is handled by Tools. Tools can be stacked.
- Versatile undo/redo system

GTK+ and PyGTK_ are required.

.. _Cairo: http://cairographics.org/
.. _PyGTK: http://www.pygtk.org/