Re: [matplotlib-devel] How to decouple non-GUI stuff from the GUI?

[John H. <jd...@gm...>]

On Fri, Nov 19, 2010 at 9:10 AM, Kynn Jones <ky...@gm...> wrote:
>
>
> When I read your message about implementing the non-GUI mode, it turns this simple picture completely on its head, which tells me that matplotlib's architecture is, at this point, beyond my comprehension.  One of the reasons for looking forward to your implementation of the non-GUI mode for the MacOSX backend is that, by studying a diff between this enhanced version and the previous version I may be able to finally understand matplotlib's basic architecture.
>

>From the introduction: http://matplotlib.sourceforge.net/users/intro.html::

  The matplotlib code is conceptually divided into three parts: the
  pylab interface is the set of functions provided by matplotlib.pylab
  which allow the user to create plots with code quite similar to
  MATLAB figure generating code (Pyplot tutorial). The matplotlib
  frontend or matplotlib API is the set of classes that do the heavy
  lifting, creating and managing figures, text, lines, plots and so on
  (Artist tutorial). This is an abstract interface that knows nothing
  about output. The backends are device dependent drawing devices, aka
  renderers, that transform the frontend representation to hardcopy or
  a display device (What is a backend?). Example backends: PS creates
  PostScript? hardcopy, SVG creates Scalable Vector Graphics hardcopy,
  Agg creates PNG output using the high quality Anti-Grain Geometry
  library that ships with matplotlib, GTK embeds matplotlib in a Gtk+
  application, GTKAgg uses the Anti-Grain renderer to create a figure
  and embed it a Gtk+ application, and so on for PDF, WxWidgets,
  Tkinter etc.

  matplotlib is used by many people in many different contexts. Some
  people want to automatically generate PostScript files to send to a
  printer or publishers. Others deploy matplotlib on a web application
  server to generate PNG output for inclusion in dynamically-generated
  web pages. Some use matplotlib interactively from the Python shell
  in Tkinter on Windows?. My primary use is to embed matplotlib in a
  Gtk+ EEG application that runs on Windows, Linux and Macintosh OS X.



Elaborating a little bit: the middle part of matplotlib, the artist
hierarchy, is what I think you are looking for.  That is where
abstractions like Line2D, Circle and Text live.  There is no concept
of a GUI or a render at that abstraction.

http://matplotlib.sourceforge.net/users/artists.html#artist-tutorial