GitHub - jdf/processing-py-site: Site for processing.py. (original) (raw)
Processing.py Documentation 
This repository contains the files and executable code used to buildpy.processing.org, the official documentation forProcessing.py.
Dependencies and installation
To build this project, you need to have the following software installed:
- Java (1.8+)
- Python (2.7+, untested with Python 3)
(Both java
and python
should be in your path.)
You'll need to install the various Python library requirements as well. These requirements are provided in this repository in the standard pip
-formattedrequirements.txt
. The easiest way to do this is to create and activate a Python virtual environment and then install the requirements with pip
like so:
pip install -r requirements.txt
(Tip: For most platforms, it's easier to install lxml
if you upgrade pip
first. With your virtual environment activated, type pip install -U pip
and then install the packages with the command above.)
Finally, you'll need the standalone Processing.py JAR file. You can build Processing.py from source to obtain this file, or download the pre-built JAR for your platform using the appropriate link below:
Unarchive the file you downloaded and copy the two files with a .jar
extension into your processing-py-site
directory.
Overview
The generator.py
script takes the various files in this repository, processes them and generates a static HTML site. (You can think of generator.py
as being a kind of bespoke static site generator, akin to, e.g.,Jekyll.) Running the following command will build the entire site:
python generator.py build --all --images
(See below for further discussion of the command line options available in generator.py
.) The best way to understand how the site is generated is to study generator.py
's source code, but here's the basic overview.
- The
Reference/api_en
directory contains a number of XML files. These files are used to generate the "Reference" section of the documentation, including the images, which are automatically generated from the<code>
blocks in the XML files. (The order of sections in the Reference index is hard-coded ingenerator.py
.) - The
Tutorials
directory has a number of subdirectories, each containing a tutorial that appears on in the "Tutorials" section. The tutorials themselves are written in plain HTML. The Tutorials index page is generated using thetutorials.xml
file to determine the order, and using thetutorial.xml
file in each subdirectory to determine metadata. - The
content
directory contains static files used in the site layout, such as stylesheets and images. The contents of this directory are simply copied verbatim to the generated site. - The
templates
directory contains a number of HTML templates, written in theJinja templating language. These are mostly used to produce the various index pages for the reference and tutorials. The XML source code for each reference item is rendered by thereference_item_template.jinja
template; there's a (fairly) straightforward correspondence between the name of the XML tag and the variable used to reference the tag in the template. - The
jython
directory contains a single script,generate_images.py
, which is used to generate images from the example code in the reference items. (This program is executed automatically by the build process; there's no reason for you to run it yourself.)
On successful completion of generator.py
, the static site ends up in thegenerated
directory.
Building the documentation
As noted above, the generator.py
script builds the site from the source files in the repository. Run python generator.py --help
for full details on its command line options. Here's an overview:
To build all content:
python generator.py build --all --images
To build the site without performing the image generation process:
python generator.py build
To build only a.xml
, b.xml
and c.xml
files from the reference (remove--images
to skip the image generation process):
python generator.py build --images --files a.xml b.xml c.xml
To test the site in a local server:
Troubleshooting
Here are a few common and/or possible scenarios you might run into...
Error: Could not find or load main class org.python.util.jython
You're missing the Jython code necessary to execute the image generation script. Ensure that you've copied (or linked) processing-py.jar
from the standalone Processing.py distribution into your processing-py-site
directory.
NullPointerException - foo is probably dynamic-mode; fix that, please.
The image generation process only creates images for "static-mode" sketches, i.e., sketches that don't have a draw()
function and therefore can't be animated or interactive. To fix this, rewrite the code example so it isn't interactive, or add <notest /><noimage />
as children of the <example>
tag in the XML to suppress image generation for that item.
Could not initialize class com.jogamp.newt.NewtFactory
I've seen this error when trying to build on Linux withoutprocessing-py-natives-linux-amd64.jar
in the processing-py-site
directory. Ensure this file (or the file appropriate for your platform) is present and try again.
I can't run the image generation process in a headless environment
If you're running on a Linux machine without a connected display (say, an EC2 box), you'll need to install xvfb
using the package manager for your operating system. Then run the build script like so:
xvfb-run python generator.py build --images
Reporting Issues
Before opening a new issue, please review existing issues.
Issues should include as many details as possible, including URLs and/or excerpts from the related material, and a description of what is missing/wrong or could be improved, and if possible how.
Contributing:
see CONTRIBUTING.md