========== Appendix ========== API and Implementation Notes ============================ External Interface ------------------ Most users of the module will use one of the following two functions. They provide a high level interface. They are also directly accessible as ``aafigure.process`` respectively ``aafigure.render``. .. module:: aafigure.aafigure .. autofunction:: aafigure.aafigure.process .. autofunction:: aafigure.aafigure.render The command line functionality is implemented in the ``main`` function. .. autofunction:: aafigure.aafigure.main Internal Interface ------------------ The core functionality is implemented in the following class. .. autoclass:: aafigure.aafigure.AsciiArtImage :members: __init__, recognize Images are built using the following shapes. Visitor classes must be able to process these types. .. automodule:: aafigure.shapes :members: Options ------- The ``options`` dictionary is used in a number of places. Valid keys (and their defaults) are: Defining the output: ``file_like`` : use the given file like object to write the output. The object needs to support a ``.write(data)`` method. ``format`` : choose backend/output format: 'svg', 'pdf', 'png' and all bitmap formats that PIL supports can be used but only few make sense. Line drawings have a good compression and better quality when saved as PNG rather than a JPEG. The best quality will be achieved with SVG, tough not all browsers support this vector image format at this time (default: ``'svg'``). Options influencing how an image is parsed: ``textual`` : disables horizontal fill detection. Fills are only detected when they are vertically at least 2 characters high (default: ``False``). ``proportional`` : use a proportional font. Proportional fonts are general better looking than monospace fonts but they can mess the figure if you need them to look as similar as possible to the ASCII art (default: ``False``). Visual properties: ``background`` : background color in the form ``#rgb`` or ``#rrggbb``, *not* for SVG output (default: ``#000000``). ``foreground`` : foreground color in the form ``#rgb`` or ``#rrggbb`` (default: ``#ffffff``). ``fill`` : fill color in the form ``#rgb`` or ``#rrggbb`` (default: same as ``foreground`` color). ``line_width`` : change line with, SVG only currently (default: ``2.0``). ``scale`` : enlarge or shrink image (default: ``1.0``). ``aspect`` : change aspect ratio. Effectively it is the width of the image that is multiplied by this factor. The default setting ``1`` is useful when shapes must have the same look when drawn horizontally or vertically. However, 0.5 looks more like the original ASCII and even smaller factors may be useful for timing diagrams and such. But there is a risk that text is cropped or is drawn over an object besides it. The stretching is done before drawing arrows or circles, so that they are still good looking (default: ``1.0``). Miscellaneous options: ``debug`` : for now, it only prints the original ASCII art figure text (default: ``False``). Visitors -------- A visitor that can be used to render the image must provide the following function (it is called by :func:`process`) .. currentmodule:: your .. class:: Visitor .. method:: visit_image(aa_image) An :class:`AsciiArtImage` instance is passed as parameter. The visiting function needs to implement a loop processing the ``shapes`` attribute. This function must take care of actually outputting the resulting image or it must provide the data in a form useful for the caller (:func:`process` returns the visitor so that the result can be read for example). Example stub class: .. code-block:: python class Visitor: def visit_image(self, aa_image): self.visit_shapes(aa_image.shapes) def visit_shapes(self, shapes): for shape in shapes: shape_name = shape.__class__.__name__.lower() visitor_name = 'visit_%s' % shape_name if hasattr(self, visitor_name): getattr(self, visitor_name)(shape) else: sys.stderr.write("WARNING: don't know how to handle shape %r\n" % shape) def visit_group(self, group): self.visit_shapes(group.shapes) # for actual output implement visitors for all the classes in # aafigure.shapes: def visit_line(self, lineobj): ... def visit_circle(self, circleobj): ... etc... Source tree ----------- The sources can be checked out using bazaar_:: bzr lp:aafigure .. _bazaar: http://bazaar-vcs.org Files in the ``aafigure`` package: ``aafigure.py`` ASCII art parser. This is the main module. ``shapes.py`` Defines a class hierachy for geometric shapes such as lines, circles etc. ``error.py`` Define common exception classes. ``aa.py`` ASCII art output backend. Intended for tests, not really useful for the end user. ``pdf.py`` PDF output backend. Depends on reportlab. ``pil.py`` Bitmap output backend. Using PIL, it can write PNG, JPEG and more formats. ``svg.py`` SVG output backend. Files in the ``docutils`` directory: ``aafigure_directive.py`` Implements the ``aafigure`` Docutils directive that takes these ASCII art figures and generates a drawing. The ``aafigure`` module contains code to parse ASCII art figures and create a list of of shapes. The different output modules can walk through a list of shapes and write image files. TODO ---- - Symbol detection: scan for predefined shapes in the ASCII image and output them as symbol from a library - Symbol libraries for UML, flowchart, electronic schematics, ... - The way the image is embedded is a hack (inserting a tag trough a raw node...) - Search for ways to bring in color. Ideas: - have an :option: to set color tags. Shapes that touch such a tag inherit it's color. The tag would be visible in the ASCII source tough:: .. aafig:: :colortag: 1:red, 2:blue 1---> --->2 - ``:color: x,y,color`` but counting coordinates is no so fun drawback: both are complex to implement, searching for shapes that belong together. It's also not always wanted that e.g. when a line touches a box, both have the same color - aafigure probably needs arguments like ``font-family``, ... - Punctuation not included in strings (now a bit improved but if it has a graphical meaning , then that is chooses, even if it makes no sense), underlines in strings are tricky to detect... - Dotted lines? ``...`` e.g. for ``---...---`` insert a dashed line instead of 3 textual dots. Vertical dashed lines should also work with ``:``. - Group shapes that belong to an object, so that it's easier to import and change the graphics in a vector drawing program. [partly done] - Path optimizer, it happens that many small lines are output where a long line could be used. 3rd party integration of aafigure ================================= There are also other projects that integrate aafigure. The following items are maintained by other developers. MediaWiki Plug-in ----------------- MediaWiki_ is a popular implementation of a WikiWikiWeb_ which is also used for WikiPedia_. A plug-in can be found here: http://www.mediawiki.org/wiki/Extension:Aafigure .. _MediaWiki: http://www.mediawiki.org .. _WikiWikiWeb: http://c2.com/cgi/wiki?WikiWikiWeb .. _WikiPedia: http://www.wikipedia.org/ AsciiDoc Plug-in ---------------- AsciiDoc_ is a plain text documentation format that can be converted into several formats such as HTML or PDF. A plug-in to use aafigure drawings in such documents can be found here: http://code.google.com/p/asciidoc-aafigure-filter/ .. _AsciiDoc: http://www.methods.co.nz/asciidoc/ Authors and Contact =================== - Chris Liechti: original author - Leandro Lucarella: provided many patches The project page is at https://launchpad.net/aafigure It should be used to report bugs and feature requests. License ======= Copyright (c) 2006-2011 aafigure-team All rights reserved. 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