README.md

Pd-L2Ork

maintainer: Ivica Ico Bukvic ico@vt.edu

maintainer: Albert Graef aggraef@gmail.com

maintainer: Jonathan Wilkes jancsika@yahoo.com

• One Paragraph Overview
• Flavors of Pure Data
• Three Paragraph Overview
• Goals
• Installation Guide
• Code of Conduct
• Contributor Guide
• Human Interface Guidelines
• Core Pd Notes
• GUI Message Spec

One Paragraph Overview

Pure Data (aka Pd) is a visual programming language. That means you can use it to create software graphically by drawing diagrams instead of writing lines of code. These diagrams show how data flows through the software, displaying on the screen what text-based languages require you to piece together in your mind.

Flavors of Pure Data

There are currently three main distributions of Pure Data:

1. Pd-L2Ork. Version used by Ivica Bukvic for his laptop orchestra. This guide is for Pd-L2Ork.
2. Pure Data "Vanilla". Miller Puckette's personal version which he hosts on his website and maintains. It doesn't include external libraries like objects for doing graphics, video, etc.
3. Pure Data Extended. A monolithic distribution which ships with lots of external libraries. As of August 2015 it hasn't been updated since January 2014.

Three Paragraph Overview

Pd has been designed with an emphasis on generating sound, video, 2D/3D graphics, and connecting through sensors, input devices, and MIDI as well as OSC devices.

Pd has a special emphasis on generating audio and/or video in real time, with low latency. Much of its design focuses on receiving, manipulating, and delivering high-quality audio signals. Specifically, the software addresses the problem of how to do this efficiently and reliably on general purpose operating systems like OSX, Windows, Debian, etc.-- i.e., systems designed mainly for multi-tasking.

Pd can easily work over local and remote networks. It can be used to integrate wearable technology, motor systems, lighting rigs, and other equipment. Pd is also suitable for learning basic multimedia processing and visual programming methods, as well as for realizing complex systems for large-scale projects.

Goals

Pd-L2ork has the following goals:

1. Documentation. We like documentation. It's like code, except friendly.
2. Be reliable. Binary releases must be usable for performances and installations. The git repo must always be in a workable state that can be compiled. Regressions must be fixed quickly.
3. Be discoverable. Undocumented features are buggy. Missing help files are bugs. Patches for new functionality that lack documentation are spam.
4. Be consistent. Consistent interfaces are themselves a kind of documentation. We like documentation, so it follows that we like consistent interfaces

Installation Guide

Linux

Time to build: 40 minutes to 1.5 hours To install using a pre-compiled binary, follow these instructions: http://l2ork.music.vt.edu/main/?page_id=56

To set up a development environment, first make sure you have the following package dependencies listed here: http://l2ork.music.vt.edu/main/?page_id=56

Then follow the steps outlined here: http://l2ork.music.vt.edu/main/?page_id=56#install-dev

OSX

Homebrew build (supported) 40 minutes to 1.5 hours

1. Install Homebrew (15 minutes) (asks for password twice-- once for command line tools, once for homebrew)
2. Install the dependencies 10 minutes: brew install wget brew install autoconf brew install automake brew install libtool brew install fftw brew install python brew install fluidsynth brew install lame brew install libvorbis brew install speex brew install gsl brew install libquicktime brew install pkg-config

3. git clone https://git.purrdata.net/jwilkes/purr-data.git 4. Change to the directory cd purr-data/l2ork_addons 5. Run the installer ./tar_em_up.sh -X *15 minutes* 6. When the installer finishes, there should be a dmg file in purr-data/packages/darwin_app

Macports build (unsupported, unfinished) Time to build: 1 day

1. Install Xcode from the Mac App Store. 1.5 hours
2. Install Xcode command line tools in a terminal window 4 minutes: xcode-select --install
3. Agree to the Xcode license in a terminal window:sudo xcodebuild -license
4. Install MacPorts 12 minutes
5. Check for updates:sudo port selfupdate
6. Install the dependencies 6 minutes: sudo port install wget sudo port install autoconf sudo port install automake sudo port install libtool sudo port install fftw-3 sudo port install fftw-3-single sudo port install python27 sudo port install fluidsynth sudo port install lame sudo port install speex sudo port install gsl sudo port install libquicktime-devel

6. Download the source code *(3-6 minutes)* Issue the following command to create a new directory "purr-data" and clone the repository to it: git clone https://git.purrdata.net/jwilkes/purr-data.git 7. ... 8. Set the environment variables on the command line: export CPATH=/opt/local/include export LIBRARY_PATH=/opt/local/lib 9. In externals/Makefile, remove the following libraries from from LIB_TARGETS: * plugin * hid * pdp * gem2pdp 10. In packages/darwin_app/Makefile, remove rez_install from build instructions 11. In packages/darwin_app/Makefile, comment out installation of libquicktime 12. Run `make install` 13. In the app in the "build" directory, find the en.lproj/InfoPlist.strings and change the CFBundleDisplayName and CFBundleName to "purr-data" 14. Note: the script `embed-MacOSX-dependencies.sh` doesn't work with macports paths.

Windows 32-bit Using msys2

Time to build: roughly 1.5 hours-- 30 minutes of this is for Gem alone

Important note: check the name of your Windows user account. If it has a space in it-- like "My Home Computer" or "2nd Laptop", then stop. You may not use this guide. (Actually you can probably just install everything in ~/.. in that case, but I haven't tested doing it like that. Sorry. Get a better OS...)

1. Download and install msys2 (5 minutes)
   There are two installers-- one for 32-bit Windows systems (i386) and one for 64-bit Windows (x_64). Be sure you know which version of Windows you are running and download the appropriate installer.
   Note: don't run it after it installs. You'll open it manually in the next step.
2. Download and install inno setup (5 minutes)
3. Run MinGW-w64 Win32 Shell (less than a minute)
   msys2 adds three Start Menu items for different "flavors" of shell:
   • MinGW-w64 Win32 Shell <- click this one!
   • MinGW-w64 Win64 Shell
   • MSYS Shell
4. Install the dependencies (5-10 minutes)
   Once the shell opens, we need to install the dependencies for building Purr Data. Issue the following command: pacman -S autoconf automake git libtool
make mingw-w64-i686-dlfcn mingw-w64-i686-fftw
mingw-w64-i686-fluidsynth
mingw-w64-i686-ftgl mingw-w64-i686-fribidi
mingw-w64-i686-ladspa-sdk mingw-w64-i686-lame
mingw-w64-i686-libsndfile mingw-w64-i686-libvorbis
mingw-w64-i686-lua mingw-w64-i686-toolchain
rsync unzip wget
5. Download the source code (3-6 minutes) Issue the following command to create a new directory "purr-data" and clone the repository to it: git clone https://git.purrdata.net/jwilkes/purr-data.git
6. Enter the purr-data/l2ork_addons directory (less than a minute) cd purr-data/l2ork_addons
7. Finally, build Purr-Data (45-80 minutes) ./tar_em_up.sh -Z
8. Look in purr-data/packages/win32_inno/Output and click the setup file to start installing Purr Data to your machine.

Code of Conduct

1. No sarcasm, please
2. Don't appear to lack empathy
3. You can't live here. If you're spending hours a day writing Purr Data code or-- worse-- spending hours a day writing emails about code that has yet to be written, you're doing it wrong
4. If working on something for the first time, ask to be mentored
5. If no one asked you to mentor them, don't teach
6. It is better to let small things go then to risk taking time away from solving bigger problems

It is a bad idea to break this Code of Conduct even if no one complains about your behavior.

Contributor Guide

Contributing is easy:

1. Join the development list: http://disis.music.vt.edu/cgi-bin/mailman/listinfo/l2ork-dev
2. Tell us what you'd like to work on. Unfortunately there are lots of externals and even core features that are poorly documented. We can help make sure you aren't duplicating functionality (or that you at least know what's already been implemented).
3. Send us your patch and we'll try it out. If it's well-documented and there aren't any bugs we'll add it to the software.
4. If you want to do regular development and have commit access, just request it, then follow the Pd-L2Ork goals above.

Here are some of the current tasks:

• writing small audio/visual Pd games or demos to include in the next release
  • skills needed: ability to write Pd programs
  • status: I wrote a little sprite-based game that will ship with the next version of Pd-L2Ork. In it, the character walks around in an actual Pd diagram shoots at the objects to progress, and to make realtime changes to the music. What I'd like is to include a new, smallish game with each release that has a link in the Pd console. It can be a little demo or game, just something fun that shows off what can be done using Pure Data.
• designing/implementing regression test template
  • skills needed: knowledge about... regression tests. :) But also some expertise in using Pd so that the tests themselves can be written in Pure Data. At the same time, they should be able to be run as part of the automated packaging process (i.e., in -nogui mode).
  • status: some externals have their own testing environments, but they are limited as they require manual intervention to run and read the results inside a graphical window. Here's an email thread with Katja Vetter's design, which looks to be automatable: http://markmail.org/message/t7yitfc55anus76i#query:+page:1+mid:chb56ve7kea2qumn+state:results And Mathieu Bouchard's "pure unity" (not sure if this is the most recent link...): http://sourceforge.net/p/pure-data/svn/HEAD/tree/tags/externals/pureunity/pureunity-0.0/

Human Interface Guidelines

General Look and Feel

Pd is a multi-window application that consists of three parts:

1. A main window, called the "Pd Window" or "Console Window". This window displays informational and error messages for Pd programs.
2. One or more "canvas" windows-- aka "patch" windows, used to display the diagrams that make up a Pd program.
3. One or more dialog windows used to configure the various parts of Pd.

All should look simple and uncluttered. Although "canvas" windows cannot (yet) be traversed and edited using only the keyboard, all three parts of Pd should be designed so that they can be manipulated using only the keyboard.

Hooks for new users

It should also be possible to produce sound and interact when a new user runs program for the very first time. In every release, there should be a link at the bottom of the Console Window to a short game written in Pd that demonstrates one or more of the capabilities of the Pd environment. The game should be designed to be fun outside of its efficacy as a demonstration of Pd.

Fonts

Pd ships with "DejaVu Sans Mono", which is used for the text in canvas windows. Fonts are sized to fit the hard-coded constraints in Pd Vanilla. This way box sizes will match as closely as possible across distributions and OSes.

These hard-coded sizes are maximum character widths and heights. No font fits these maximums exactly, so it's currently impossible to tell when looking at a Pd canvas whether the objects will collide on a system using a different font (or even a different font-rendering engine).

Dialogs and console button labels may use variable-width fonts. There is not yet a suggested default to use for these.

The console printout area currently uses "DejaVu Sans Mono". Errors are printed as a link so that the user can click them to highlight the corresponded canvas or object that triggered the error.

Colors

Nothing set in stone yet.

Core Pd Notes

The following is adapted from Pd Vanilla's original source notes. (Found in pd/src/CHANGELOG.txt for some reason...)

Sections 2-3 below are quite old. Someone needs to check whether they even hold true for Pd Vanilla any more.

Structure definition roadmap.

First, the containment tree of things that can be sent messages ("pure data"). (note that t_object and t_text, and t_graph and t_canvas, should be unified...)

BEFORE 0.35:

m_pd.h	    t_pd    	    	    anything with a class
                t_gobj	    	    "graphic object"
                    t_text  	    text object
g_canvas.h  
                    t_glist 	    list of graphic objects
g_canvas.c  	    	t_canvas    Pd "document"

AFTER 0.35:

m_pd.h	    t_pd    	    	    anything with a class
                t_gobj	    	    "graphic object"
                    t_text  	    patchable object, AKA t_object
g_canvas.h     	    	t_glist     list of graphic objects, AKA t_canvas

Other structures:

g_canvas.h  t_selection -- linked list of gobjs
            t_editor -- editor state, allocated for visible glists
m_imp.h     t_methodentry -- method handler
            t_widgetbehavior -- class-dependent editing behavior for gobjs
            t_parentwidgetbehavior -- objects' behavior on parent window
            t_class -- method definitions, instance size, flags, etc.

1. Coding Style