README.md

Pd-L2Ork

Maintainers:

• Ivica Ico Bukvic ico@vt.edu
• Albert Graef aggraef@gmail.com
• Jonathan Wilkes jancsika@yahoo.com

Mailing List

• Downloads
• One Paragraph Overview
• Three Paragraph Overview
• Goals
• User Guide
• Relationship of Purr Data to Pure Data
• Build Guide
  • Gnu/Linux
  • OSX
  • Windows
• Code of Conduct
• Project Governance
• 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.

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.

User Guide and Weblinks

For a more in-depth look at Purr Data for new users and developers, see:

https://agraef.github.io/purr-data-intro/Purr-Data-Intro.html

For more resources see:

https://agraef.github.io/purr-data/

For Ico Bukvic's original Pd-l2ork website see:

http://l2ork.music.vt.edu/main/make-your-own-l2ork/software/

(Note that the latter link is more about "classic" Pd-L2Ork a.k.a. Pd-L2Ork 1.0, see below. But it also contains some information about Purr Data.)

Relationship of Purr Data to Pure Data

There are three maintained distributions of Pure Data:

1. Purr Data. This is the 2.0 version of Pd-l2ork. It ships with lots of external libraries and uses a modern GUI written using HTML5.
2. Pd-L2Ork 1.0, the version used by Ivica Bukvic for his laptop orchestra. Pd-l2ork 1.0 uses tcl/tk (and tkpath) for the GUI. You can find it here.
3. Pure Data "Vanilla". Miller Puckette's personal version which he hosts on his website and maintains. It doesn't come with external libraries pre-installed, but it does include an interface you can use to search and install external libraries maintained and packaged by other developers.

Downloads

Windows and OSX:

Releases are done on GitHub:

https://github.com/jonwwilkes/purr-data/releases

This is where the packages first come out as soon as Jonathan Wilkes releases them. The same packages can also be dowloaded (usually shortly after release) on Albert Gräf's mirror, which also provides a website, wiki, additional documentation, and an up-to-date mirror of the source code repository:

https://github.com/agraef/purr-data/releases

Linux:

Packages for various Linux distributions (including Arch, Debian, Ubuntu, and openSUSE) are available through the JGU package repositories maintained by Albert Gräf on the OBS (Open Build System). Detailed instructions can be found here.

You can also just go to the OBS Download, pick your Linux system, and follow the instructions.

Build Guide

Purr Data is usually built by just running make in the toplevel source directory after checking out the sources from its git repository. This works across all supported platforms (Linux, Mac and Windows at this time). The Makefile also offers the customary targets to clean (make clean, or make realclean to put the sources in pristine state again) and to roll a self-contained distribution tarball (make dist), as well as some other convenience targets (please check the comments at the beginning of the Makefile for more information).

However, to make this work, you will most likely have to install some prerequisites first: build tools such as a C/C++ compiler and the make program itself, as well as dependencies, the libraries that Purr Data needs. Detailed instructions for each of the supported platforms are given below.

Linux

Time to build: 10 minutes light install, 45 minutes to 1.5 hours full install Hard drive space required: roughly 2.5 GB

0. Remember to update your packages:

    sudo apt-get update && sudo apt-get upgrade

1. Install the dependencies (please note that the packages may be named slightly differently for different Linux distributions; the given names are for Debian/Ubuntu)

    sudo apt-get install bison flex automake libasound2-dev \
         libjack-jackd2-dev libtool libbluetooth-dev libgl1-mesa-dev \
         libglu1-mesa-dev libglew-dev libmagick++-dev libftgl-dev \
         libgmerlin-dev libgmerlin-avdec-dev libavifile-0.7-dev \
         libmpeg3-dev libquicktime-dev libv4l-dev libraw1394-dev \
         libdc1394-22-dev libfftw3-dev libvorbis-dev ladspa-sdk \
         dssi-dev tap-plugins invada-studio-plugins-ladspa blepvco \
         swh-plugins mcp-plugins cmt blop slv2-jack omins rev-plugins \
         libslv2-dev dssi-utils vco-plugins wah-plugins fil-plugins \
         mda-lv2 libmp3lame-dev libspeex-dev libgsl0-dev \
         portaudio19-dev liblua5.3-dev python-dev libsmpeg0 libjpeg62-turbo \
         flite1-dev libgsm1-dev libgtk2.0-dev git libstk0-dev \
         libfluidsynth-dev fluid-soundfont-gm byacc

2. The gui toolkit may require installing the following extra dependencies

    sudo apt-get install gconf2 libnss3

3. Clone the Purr-Data repository (2 to 10 minutes)

    git clone https://git.purrdata.net/jwilkes/purr-data.git

4. Compile the code (5 minutes [light] to 1.5 hours [full])

   • to build only the core: make light (5 minutes)
   • to build the core and all externals: make all (20 minutes to 1.5 hours)
   • to build everything except Gem: make incremental (10 to 20 minutes)

5. If you're using an apt-based Linux distribution and you have the necessary Debian packaging tools installed, there should now be an installer file in the main source directory, which can be installed as usual. Otherwise, run make install to install the software, and make uninstall to remove it again.

OSX 64-bit using Homebrew

Time to build: 50 minutes to 1.5 hours
Hard drive space required: roughly 2 GB

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 lua
    brew install fluidsynth
    brew install lame
    brew install libvorbis
    brew install speex
    brew install gsl
    brew install libquicktime
    brew install pkg-config

3. Clone the Purr-Data repository (10 minutes)

    git clone https://git.purrdata.net/jwilkes/purr-data.git

4. Change to the source directory

    cd purr-data

5. Build the OSX app and the installer disk image (.dmg file) (15 minutes)

    make

6. There should now be a .dmg file in your current directory, which lets you install the app in the usual way

Windows 32-bit Using msys2

Time to build: roughly 1.5 hours-- 30 minutes of this is for Gem alone
Hard drive space required to build: rougly 2.5 GB

Important note: We recommend doing the build under your msys2 home directory (usually /home/username in the msys2 shell). This directory should not have any spaces in it, which would otherwise cause trouble during the build. Never try using your Windows home directory for this purpose instead, since it will usually contain spaces, making the build fail.

1. Download and install msys2 (5 minutes)
   There are two installers-- one for 32-bit Windows systems (i686) and one for 64-bit Windows (x86_64). Be sure you know which version of Windows you are running and download the appropriate installer.
   Note: don't run the shell after installation finishes. You'll do that manually in step 3.

2. Download and install the inno setup Quickstart Pack which includes the Script Editor (5 minutes)

3. Run the "MSYS2 MinGW 32-bit" shell (less than a minute)
   msys2 adds three Start Menu items for different "flavors" of shell:

   • MSYS2 MinGW 32-bit <- click this one!
   • MSYS2 MinGW 64-bit
   • MSYS2 MSYS

4. Install the dependencies (5-10 minutes)
   Once the shell opens, we need to install the dependencies for building Purr Data. First we need to update all the packages:

    pacman -Syu

   After closing and reopening the shell as prompted, you may need to do it again:

    pacman -Syu

   Now everything should be up-to-date. 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-SDL2 \
      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 \
      mingw-w64-i686-libjpeg-turbo \
      mingw-w64-i686-speex \
      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 source directory (less than a minute)

    cd purr-data

7. Finally, build Purr-Data (45-80 minutes)

    make

8. Look in the top level source directory and double-click the setup file to start installing Purr Data on your system.

Windows 64-bit Using msys2

The instructions are exactly the same as for the 32 bit build (see above), but the build needs to be done using mingw64 instead of mingw32. That is:

• Install the mingw64 packages for the dependencies. See the i686 packages listed under dependencies above, and replace i686 with x86_64 in the package names when installing.

• Use the MSYS2 MinGW 64-bit shell (rather than the 32-bit shell) to do the build.

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 behaviour.

Project Governance

• The three maintainers listed at the top of this document are the ones in charge of this project.
• Unanimous decisions are preferred.
• 2 out of 3 can break a disagreement.
• There will only ever be three maintainers of this project at any given time. If you'd like to temporarily step in as one of the three, send an inquiry to the list and we can discuss it.

Contributor Guide

Contributing is easy:

1. Join the development list: http://disis.music.vt.edu/cgi-bin/mailman/listinfo/l2ork-dev
2. Fork Purr Data using the gitlab UI and then try to build it from source for your own platform using the Build Guide above. If you run into problems ask on the development list for help.
3. Once you have successfully built Purr Data, install it and make sure it runs correctly.
4. Start making changes to the code with brief, clear commit messages. If you want some practice you can try fixing one of the bugs on the issue tracker labeled "good-first-bug"
5. One you are done fixing the bug or adding your feature, make a merge request in the Gitlab UI so we can merge the fix for the next release.

A few guidelines:

• There should be a short and clear commit message for each merge request.
• Short and clear title and description are required for each merge request.
• There should be a short branch name related to the issue, like "update-readme".
• No prototypes, please. Purr Data's biggest strength is that users can turn an idea into working code very quickly. But a prototyping language that is itself a prototype isn't very useful. That means Purr Data's core code and libraries must be stable, consistent, well-documented, and easy to use.
• Develop incrementally. Small, solid improvements to the software are preferable to large, disruptive ones.
• Try not to duplicate existing functionality. For backwards compatibility Purr Data ships many legacy libraries which unfortunately duplicate the same functionality. This makes it harder to learn how to use Pd, and makes it burdensome to read patches and keep track of all the disparate implementations.
• Keep dependencies to a minimum. Cross-platform dependency handling is unfortunately still an open research problem. In the even that you need an external library dependency, please mirror it at git.purrdata.net so that the build system doesn't depend on the availability of external infrastructure.

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. We currently have a crude test system that at least ensures that each external library instantiates without crashing. 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/
• Adding support for double precision to the external libraries that ship with purr-data
  • Skills needed: Knowledge about data types in C language(specially float and double)
  • Status: The core classes of purr data and the freeverb~ external library have been changed to support both float and double but still the remaining external libraries only have support for single precision. The task ahead is to add double precision support to these external libraries. As per the current resources we have the merge requests that have been used to add double precision support to the core libraries: https://git.purrdata.net/jwilkes/purr-data/merge_requests?scope=all&utf8=%E2%9C%93&state=merged&author_username=pranay_36 And Katja Vetter's double precision patches to the pd-double project which were actually used for adding double precision support to the core libraries of purr-data. https://github.com/pd-projects/pd-double/commit/982ad1aa1a82b9bcd29c5b6a6e6b597675d5f300

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