[matplotlib-devel] First release of an object oriented style system

[Drain, T. R (392P) <the...@jp...>]

Last year we implemented an object oriented plotting style system for our users and I was able to convince our management that we should open source it.  You can find it here:  https://github.com/nasa/mplStyle

Many (most?) of the existing MPL style systems seem to be built around RC parameters which doesn't work very well for us.  For a large system that can create plots in many different scripts/GUI's, we really can't change global settings (RC's) to affect how a plot looks as it ends up screwing up plots in other areas.  So we designed an OO based style system that allows you to create/save/load styles and apply them to individual plot elements (text, lines, axes, figures, etc).

This code was extracted from a much larger project so it wasn't really written as a standalone library or designed to follow MPL's naming and coding conventions.  i.e. don't assume the internals exhibit any great design - I was mostly concerned with getting a stand alone package that worked in the minimum amount of effort.  It does work fine, every method has documentation, and test cases are included (feel free to email me or use github if you find any problems) but my real hope is that it either serves as an inspiration for building a standard MPL OO style system (or perhaps it can be morphed into that over time).

Some of the features include:
- Object oriented style objects (no changes to global RC parameters)
- Apply styles to whole figures or to individual plot elements (artists, patches, axes, etc)
- Save and load styles into human editable files
- Apply styles by name or by style object
- Styles remember what they were applied to and can be told to re-apply after changes.  This is great way to try out style settings without having to regenerate a plot.
- Plot elements can be tagged with a name.  The tag name can later be used as a target in the style application.  This is great feature for plotting libraries as it allows a script to create plot elements with a set of names and the caller can apply various styles to the plot elements by using those names.  This separates plot creation from plot styling and makes plotting code much easier to reuse as users don't need to edit the plotting script just to change the style of a line.

Please take a look and let us know what you think.  
Ted
ps: FYI for clarity I wasn't the primary author of this code - James Evans get's that honor with various contributions from a variety of people who work on our development team.