26.5 KB
Newer Older
## Pd-L2Ork

Jonathan Wilkes's avatar
Jonathan Wilkes committed

5 6 7
* Ivica Ico Bukvic <>
* Albert Graef <>
* Jonathan Wilkes <>
Jonathan Wilkes's avatar
Jonathan Wilkes committed

[Mailing List](

* [Downloads](#downloads)
12 13 14
* [One Paragraph Overview](#one-paragraph-overview)
* [Three Paragraph Overview](#three-paragraph-overview)
* [Goals](#goals)
Jonathan Wilkes's avatar
Jonathan Wilkes committed
* [User Guide](#user-guide)
Rishabh Gupta's avatar
Rishabh Gupta committed
* [Relationship of Purr Data to Pure Data](#relationship-of-purr-data-to-pure-data)
* [Build Guide](#build-guide)
18 19 20
  * [Gnu/Linux](#linux)
  * [OSX](#osx-64-bit-using-homebrew)
  * [Windows](#windows-32-bit-using-msys2)
* [Code of Conduct](#code-of-conduct)
* [Contributor Guide](#contributor-guide)
Jonathan Wilkes's avatar
Jonathan Wilkes committed
* [Human Interface Guidelines](#human-interface-guidelines)
* [Core Pd Notes](#core-pd-notes)
* [GUI Message Spec](#gui-messaging-specification)

Jonathan Wilkes's avatar
Jonathan Wilkes committed
### One Paragraph Overview

Jonathan Wilkes's avatar
Jonathan Wilkes committed
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
Jonathan Wilkes's avatar
Jonathan Wilkes committed
code.  These diagrams show how data flows through the software, displaying on
32 33
the screen what text-based languages require you to piece together in your mind.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
### Three Paragraph Overview
35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51

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.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
### Goals

Pd-L2ork has the following goals:
Jonathan Wilkes's avatar
Jonathan Wilkes committed

Jonathan Wilkes's avatar
Jonathan Wilkes committed
56 57
1. Documentation.  We like documentation.  It's like code, except friendly.
2. Be reliable.  Binary releases must be usable for performances and
58 59
   installations.  The git repo must always be in a workable state that can be
   compiled.  Regressions must be fixed quickly.
Jonathan Wilkes's avatar
Jonathan Wilkes committed
3. Be discoverable.  Undocumented features are buggy.  Missing help files are
   bugs.  Patches for new functionality that lack documentation are spam.
Jonathan Wilkes's avatar
Jonathan Wilkes committed
4. Be consistent.  Consistent interfaces are themselves a kind of
   documentation.  We like documentation, so it follows that we like consistent

Jonathan Wilkes's avatar
Jonathan Wilkes committed
### User Guide
67 68 69 70 71

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


Jonathan Wilkes's avatar
Jonathan Wilkes committed
72 73 74 75
For more resources see:


Rishabh Gupta's avatar
Rishabh Gupta committed
76 77 78 79 80 81 82 83 84 85 86 87 88 89
### 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
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.

90 91
### Downloads

Jonathan Wilkes's avatar
Jonathan Wilkes committed
For Ubuntu PPAs and Arch AUR:

94 95

Jonathan Wilkes's avatar
Jonathan Wilkes committed
Packages for Gnu/Linux, Windows, and OSX:

98 99
### Build Guide

Akshat Maheshwari's avatar
Akshat Maheshwari committed
**NOTE:** The instructions for Windows and OSX below talk about running the `` build
103 104 105 106 107 108 109 110
script, which is still the recommended way to build Purr Data right now.
However, Purr Data also has a new (and experimental) toplevel Makefile so that
just typing `make` will build the package. You may find this easier. 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`). Please check the comments
at the beginning of the Makefile for more information.

#### Linux

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

116 117
1. Install the dependencies

        sudo apt-get install bison flex automake libasound2-dev \
119 120 121 122 123
             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 \
124 125
             dssi-dev tap-plugins invada-studio-plugins-ladspa blepvco \
             swh-plugins mcp-plugins cmt blop slv2-jack omins rev-plugins \
126 127
             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 \
Jonathan Wilkes's avatar
Jonathan Wilkes committed
             flite1-dev libgsm1-dev libgtk2.0-dev git libstk0-dev \
             libsndobj-dev libfluidsynth-dev fluid-soundfont-gm byacc

132 133
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

4. Compile the code *(5 minutes to 1.5 hours)* full 

141 142 143
   * to build only the core: `make light` *(5 minutes)*
   * to build core and all externals: `make all` *(20 minutes to 1.5 hours)*
   * to build everything *except* Gem: `make incremental` *(10 to 20 minutes)*

145 146 147 148
5. There should now be an installer file in the main directory of the repo. 
   If you're using an apt-based Linux distribution it will be an apt package.
   Otherwise, it will be a tarball which you can unzip, enter, and run
   `make install` (as well as `make uninstall` to remove it).

150 151 152 153 154 155 156 157 158 159
To install using a pre-compiled binary, follow these instructions:

To set up a development environment, first make sure you have the following
package dependencies listed here:

Then follow the steps outlined here:

#### OSX 64-bit using Homebrew
161 162

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)
167 168 169 170 171 172 173 174 175

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
177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200
        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

4. Change to the directory

        cd purr-data/l2ork_addons

5. Run the installer *(15 minutes)*

        ./ -X

6. When the installer finishes, type

        cd ..

7. There should now be a .dmg file in your current directory

#### Windows 32-bit Using msys2
204 205

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*
Jonathan Wilkes's avatar
Jonathan Wilkes committed

208 209 210 211
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)*  
214 215 216 217 218 219 220
   There are two installers-- one for 32-bit Windows systems (i386) and one for
   64-bit Windows (x_64). Be sure you know which
   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

2. Download and install [inno setup]( *(5 minutes)*

3. Run MinGW-w64 Win32 Shell *(less than a minute)*  
224 225 226 227 228
   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)*  
Jonathan Wilkes's avatar
Jonathan Wilkes committed
   Once the shell opens, we need to install the dependencies for building
nerrons's avatar
nerrons committed
   Purr Data. First we need to update all the packages:

        pacman -Syu
nerrons's avatar
nerrons committed

nerrons's avatar
nerrons committed
235 236 237 238 239 240
   After closing and reopening the shell as prompted, you may need to do it
        pacman -Syu
   Now everything should be up-to-date. Issue the following command:
nerrons's avatar
nerrons committed

        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 \
246 247
          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 \
250 251 252
          rsync unzip wget

5. Download the source code *(3-6 minutes)*  
Jonathan Wilkes's avatar
Jonathan Wilkes committed
   Issue the following command to create a new directory "purr-data" and clone
254 255 256 257 258 259 260 261 262 263 264 265
   the repository to it:

        git clone

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)*

        ./ -Z

8. Look in the top level directory of the Git repository and click the setup file to
   start installing Purr Data to your machine.

269 270
### Code of Conduct

1. No sarcasm, please
2. Don't appear to lack empathy
273 274 275 276 277 278 279 280
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

281 282
It is a bad idea to break this Code of Conduct *even if* no one complains
about your behavior.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
### Contributor Guide
Jonathan Wilkes's avatar
Jonathan Wilkes committed

Contributing is easy:
Jonathan Wilkes's avatar
Jonathan Wilkes committed

288 289
1. Join the development list:
290 291 292 293 294 295 296 297 298 299 300 301 302
2. Fork Purr Data using the gitlab UI and then try to build it from source
   for your own platform using the [Build Guide](#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
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:
303 304 305
* 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".
306 307 308 309 310 311
* _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.
312 313
* Try not to duplicate existing functionality.
  For backwards compatibility Purr Data ships many legacy
314 315 316
  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.
317 318 319 320 321
* 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
  so that the build system doesn't depend on the availability of external

Jonathan Wilkes's avatar
Jonathan Wilkes committed
323 324 325
Here are some of the current tasks:

* writing small audio/visual Pd games or demos to include in the next release
Jonathan Wilkes's avatar
Jonathan Wilkes committed
  * skills needed: ability to write Pd programs
Jonathan Wilkes's avatar
Jonathan Wilkes committed
  * 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
Jonathan Wilkes's avatar
Jonathan Wilkes committed
329 330 331 332 333
    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
Jonathan Wilkes's avatar
Jonathan Wilkes committed
  * skills needed: knowledge about... regression tests. :)  But also some
Jonathan Wilkes's avatar
Jonathan Wilkes committed
336 337 338 339 340 341 342
    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.
343 344
    We currently have a crude test system that at least ensures that each
    external library instantiates without crashing.
Jonathan Wilkes's avatar
Jonathan Wilkes committed
345 346 347 348 349 350
    Here's an email thread with Katja Vetter's design, which looks to
    be automatable:
    And Mathieu Bouchard's "pure unity" (not sure if this is the most
    recent link...):
351 352 353 354 355 356 357 358 359 360 361 362
* 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:
    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.

364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407
### 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.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
### Core Pd Notes

Jonathan Wilkes's avatar
Jonathan Wilkes committed
410 411
The following is adapted from Pd Vanilla's original source notes.  (Found
in pd/src/CHANGELOG.txt for some reason...)
412 413

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

Jonathan Wilkes's avatar
Jonathan Wilkes committed
416 417 418
#### Structure definition roadmap.

First, the containment tree of things
419 420 421 422
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:
Jonathan Wilkes's avatar
Jonathan Wilkes committed

424 425 426 427 428 429
    m_pd.h      t_pd                        anything with a class
                    t_gobj                  "graphic object"
                        t_text              text object
                        t_glist             list of graphic objects
    g_canvas.c              t_canvas        Pd "document"
430 431

AFTER 0.35:
Jonathan Wilkes's avatar
Jonathan Wilkes committed

433 434 435 436
    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
437 438

Other structures:
Jonathan Wilkes's avatar
Jonathan Wilkes committed
439 440 441 442 443 444 445

    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.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
#### 1. Coding Style

Jonathan Wilkes's avatar
Jonathan Wilkes committed
1.0  C coding style.  The source should pass most "warnings" of C compilers
(-Wall on Linux, for instance-- see the makefile.)  Some informalities
451 452 453 454 455
are intentional, for instance the loose use of function prototypes (see
below) and uncast conversions from longer to shorter numerical formats.
The code doesn't respect "const" yet.

1.1.  Prefixes in structure elements.  The names of structure elements always
have a K&R-style prefix, as in `((t_atom)x)->a_type`, where the `a_` prefix
indicates "atom."  This is intended to enhance readability (although the
458 459 460 461 462 463 464 465 466 467 468 469
convention arose from a limitation of early C compilers.)  Common prefixes are:
  * `w_` (word)
  * `a_` (atom)
  * `s_` (symbol)
  * `ob_` (object)
  * `te_` (text object)
  * `g_` (graphical object)
  * `gl_` (glist, a list of graphical objects).

Also, global symbols sometimes get prefixes, as in `s_float` (the symbol whose
string is "float").  Typedefs are prefixed by `t_`.  Most _private_ structures,
i.e., structures whose definitions appear in a ".c" file, are prefixed by `x_`.
470 471

1.2.   Function arguments.  Many functions take as their first
472 473 474
argument a pointer named `x`, which is a pointer to a structure suggested
by the function prefix; e.g., `canvas_dirty(x, n)` where `x` points to a canvas
`(t_canvas *x)`.
475 476 477 478 479 480 481 482 483 484 485 486 487

1.3.  Function Prototypes.  Functions which are used in at least two different
files (besides where they originate) are prototyped in the appropriate include
file. Functions which are provided in one file and used in one other are
prototyped right where they are used.  This is just to keep the size of the
".h" files down for readability's sake.

1.4.  Whacko private terminology.  Some terms are lifted from other historically
relevant programs, notably "ugen" (which is just a tilde object; see d_ugen.c.)

1.5.  Spacing.  Tabs are 8 spaces; indentation is 4 spaces.  Indenting
curly brackets are by themselves on their own lines, as in:

Jonathan Wilkes's avatar
Jonathan Wilkes committed
488 489 490 491 492 493
if (x)
    x = 0;
494 495 496

Lines should fit within 80 spaces.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
497 498 499
#### 2. Compatibility with Max

2.0.  Max patch-level compatibility.  "Import" and "Export" functions are
500 501 502 503 504 505 506
provided which aspire to strict compatibility with 0.26 patches (ISPW version),
but which don't get anywhere close to that yet.  Where possible, features
appearing on the Mac will someday also be provided; for instance, the connect
message on the Mac offers segmented patch cords; these will devolve into
straight lines in Pd.  Many, many UI objects in Opcode Max will not appear in
Pd, at least at first.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
507 508 509
#### 3. Source-level Compatibility with Max

3.0.  Compatibility with Max 0.26 "externs"-- source-level compatibility. Pd
510 511 512 513 514 515 516 517 518
objects follow the style of 0.26 objects as closely as possible, making
exceptions in cases where the 0.26 model is clearly deficient.  These are:

3.1.  Anything involving the MacIntosh "Handle" data type is changed to use
char * or void * instead.

3.2.  Pd passes true single-precision floating-point arguments to methods;
Max uses double.
Typedefs are provided:

520 521 522 523 524 525 526 527 528 529
    t_floatarg, t_intarg for arguments passed by the message system
    t_float, t_int for the "word" union (in atoms, for example.)

3.3.  Badly-named entities got name changes:

    w_long --> w_int (in the "union word" structure)

3.4.  Many library functions are renamed and have different arguments;
I hope to provide an include file to alias them when compiling Max externs.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
530 531 532
#### 4. Function name prefixes

4.0.  Function name prefixes.
533 534
Many function names have prefixes which indicate what "package" they belong
to.  The exceptions are:
Jonathan Wilkes's avatar
Jonathan Wilkes committed

536 537 538 539 540
    typedmess, vmess, getfn, gensym (m_class.c)
    getbytes, freebytes, resizebytes (m_memory.c)
    post, error, bug (s_print.c)
which are all frequently called and which don't fit into simple categories.
Important packages are:

Jonathan Wilkes's avatar
Jonathan Wilkes committed
    (pd-gui:)   pdgui -- everything
    (pd:)       pd -- functions common to all "pd" objects
Jonathan Wilkes's avatar
Jonathan Wilkes committed
544 545 546 547 548
                obj -- fuctions common to all "patchable" objects ala Max
                sys -- "system" level functions
                binbuf -- functions manipulating binbufs
                class -- functions manipulating classes
                (other) -- functions common to the named Pd class

Jonathan Wilkes's avatar
Jonathan Wilkes committed
550 551 552
#### 5. Source file prefixes

5.0. Source file prefixes. 


Jonathan Wilkes's avatar
Jonathan Wilkes committed
556 557 558 559 560 561
    s    system interface
    m    message system
    g    graphics stuff
    d    DSP objects
    x    control objects
    z    other
562 563


Jonathan Wilkes's avatar
Jonathan Wilkes committed
    gui    GUI front end
566 567 568 569 570 571

#### 6. Javascript style
1. Brackets on the same line as declaration or expression: `if (a) {`
2. Single line comments only: `//`
3. Use double-quotes for strings
4. Use underscores to separate words of function names and variables
Jonathan Wilkes's avatar
Jonathan Wilkes committed
572 573

### GUI Messaging Specification
Jonathan Wilkes's avatar
Jonathan Wilkes committed
#### Public GUI interface
Jonathan Wilkes's avatar
Jonathan Wilkes committed
575 576 577 578 579 580 581 582 583 584 585 586 587 588 589

Purpose: a set of functions to communicate with the gui without putting
language-specific strings (like tcl) into the C code.  The new interface is a
step toward separating some (but not all) of the GUI logic out from the C code.
Of course the GUI can still be designed to parse and evaluate incoming messages
as commands.  But the idiosyncracies of the GUI toolkit can be limited to
either the GUI code itself or to a small set of modular wrappers around

The public interface consists of the following:

gui_vmess(const char *msg, const char *format, ...);

where `const char *format` consists of zero or more of the following:
Jonathan Wilkes's avatar
Jonathan Wilkes committed

592 593 594
* f - floating point value (`t_float`)
* i - integer (`int`)
* s - c string (`char*	)
Jonathan Wilkes's avatar
Jonathan Wilkes committed
* x - hexadecimal integer value, with a precision of at least six digits.
      (hex value is preceded by an 'x', like `x123456`)
Jonathan Wilkes's avatar
Jonathan Wilkes committed
597 598 599 600 601

For some of Pd's internals like array visualization, the message length may
vary. For these _special_ cases, the following functions allow the developer
to iteratively build up a message to send to the GUI.

Jonathan Wilkes's avatar
Jonathan Wilkes committed
602 603
gui_start_vmess(const char *msg, const char *format, ...);
604 605 606 607 608 609
gui_start_array();      // start an array
gui_f(t_float float);   // floating point array element (t_float)
gui_i(int int);         // integer array element (int)
gui_s(const char *str); // c string array element
gui_end_array();        // end an array
gui_end_vmess();        // terminate the message
Jonathan Wilkes's avatar
Jonathan Wilkes committed
610 611 612 613 614 615 616 617 618 619 620 621

The above will send a well-formed message to the GUI, where the number of array
elements are limited by the amount of memory available to the GUI. Because of
the complexity of this approach, it may _only_ be used when it is necessary to
send a variable length message to the GUI. (Some of the current code may
violate this rule, but that can be viewed as a bug which needs to get fixed.)

The array element functions gui_f, gui_i, and gui_s may only be used inside an
array.  Arrays may be nested, but this adds complexity and should be avoided if

Jonathan Wilkes's avatar
Jonathan Wilkes committed
#### Private Wrapper for Nw.js Port
Jonathan Wilkes's avatar
Jonathan Wilkes committed
623 624 625 626 627 628 629 630 631 632 633 634 635 636

The public functions above should fit any sensible message format.
Unfortunately, Pd's message format (FUDI) is too simplistic to handle arbitrary
c-strings and arrays, so it cannot be used here. (But if it happens to improve
in the future it should be trivial to make a wrapper for the public interface

The current wrapper was made with the assumption that there is a Javascript
Engine at the other end of the message. Messages consist of a selector,
followed by whitespace, followed by a comman-delimited list of valid Javascript
primitives (numbers, strings, and arrays). For the arrays, Javascript's array
notation is used. This is a highly idiosyncratic, quick-and-dirty approach.
But the point is that the idiosyncracy exists in a single file of the source
code, and can be easily made more modular (or replaced entirely by something
else) without affecting _any_ of the rest of the C code.