Forem: Jérémie Astor

Gwion changes home! (aka growing from hacktoberfest)

Jérémie Astor — Sun, 18 Oct 2020 19:53:21 +0000

A few years ago, I started writing a programming language to help me in various musical tasks: I loved chuck so much, but I came to a point where it was not that usable in terms of performance, so I decided to make my own.

It was a great opportunity to learn about more programming and to add a few feature if missed (sometimes badly) in chuck: things like function pointers and generics, to start with.

It all finally came to the point where a team built and, Hacktoberfest helping, I had to move all that work on the organization account.

In the end, I think and hope it'll help this project grow, become more and more usable and build its community.

Don't forget is still hacktoberfest, and you can contribute this project! A summary on all issues can be found here.

If you are interrested in participating in Gwion's developement project, please comment here, we will be happy to invite you.

Hello, Gwion!

Jérémie Astor — Mon, 28 Sep 2020 16:00:53 +0000

Hello, Gwion!

I've been posting about Gwion here for a while, but never explaining quite clearly what the project could do.
I'm hoping this post while help people have an idea of that.
At the end of this tutorial, you should be able to hear sound generated by Gwion in your browser 😄

Dependencies

Please make sure all these are installed on your computer:

A C compiler. Gwion is tested with gcc and clang
make
a terminal emulator. (I use kitty)
libwebsockets
Soundpipe. The original repo has been removed, but you can still find copy on github. You can try this one

Now you're all set, let me suggest you first follow instructions in
this short post and get back reading here, it'll save you most of the burden (as in just read 😄)

Gwion

First we need to get gwion, we'll follow the basic procedure,
but we will also need some plugins, so we add plug to the submodule update command

install_gwion.sh

git clone https://github.com/fennecdjay/Gwion
cd Gwion
git submodule update --init util ast plug
make

Building the plugins

For this project we need a few plugins.

Let's build them too.

plugins.sh

cd Gwion/plug/Soundpipe
make
cd ../Modules
make
cd ../WebSocket
make

The browser part

Now, since the goal is to hear Gwion's audio output from the browser,
we'll need some javascript and html

gwion_ws_test.js

const URL = "ws://localhost:1111"
const BUFLEN = 512;
const NCHAN = 2;
var ws;
var scriptNode;
var audioCtx;
var outsamples = new Float32Array(BUFLEN);
var volume = 0.5;

function gwionWsSetVolume(value) {
  volume = value;
}

function gwionWsFillBuffer(audioProcessingEvent) {
  ws.send("next");
  var outputBuffer = audioProcessingEvent.outputBuffer;
  for (var channel = 0; channel < NCHAN; channel++) {
    var outputData = outputBuffer.getChannelData(channel);
    for (var sample = 0; sample < BUFLEN; sample++)
      outputData[sample] = outsamples[sample + channel*BUFLEN] * volume;
  }
}

function gwionWsOnOpen()  {
  audioCtx = new (window.AudioContext || window.webkitAudioContext)();
  console.log(audioCtx.sampleRate);
  scriptNode = audioCtx.createScriptProcessor(BUFLEN, NCHAN, NCHAN);
  scriptNode.onaudioprocess = gwionWsFillBuffer;
  scriptNode.connect(audioCtx.destination);
}

function gwionWsOnMessage(e)  {
//  if(e.data instanceof ArrayBuffer)
  outsamples = new Float32Array(e.data);
}

function gwionWsOnClose()  {
  if(audioCtx) {
    scriptNode.disconnect();
    audioCtx.close();
    alert("Connection closed");
  }
}

function gwionWsInit() {
  ws = new WebSocket(URL);
  if(!ws)
    alert("Web socket server not found at url: " + URL);
  ws.onopen = gwionWsOnOpen;
  ws.onmessage = gwionWsOnMessage;
  ws.onclose = gwionWsOnClose;
  ws.binaryType = "arraybuffer";
}

function gwionWsOnLoad() {
  if ("WebSocket" in window)
    gwionWsInit();
  else
    alert("WebSocket NOT supported by your Browser!");
}

gwion_ws_test.html

<!DOCTYPE HTML>
<html>
  <script src="gwion_ws_test.js"></script>
  <body>
  <p><button onclick="gwionWsOnLoad();">Connect</button><p>
  <p><input id="volumeSlider" type="range" min="0" max="1" value="0.5" step="0.01" oninput>
  </body>
</html>

Contributing

You quite probably have a better knowledge of javascript than me.
Feel free to share your improvements and submit a PR.
Using Web assembly and switching from ScriptProcessor to AudioWorklet
would be great additions!

Some life-easing script

Now we got all the pieces.

We just need to assemble all this.

ease.sh

# create a 'libs' directory to store our plugins
mkdir libs
# copy all the plugins we built into 'libs'
cp Gwion/plug/*/*.so libs
# '-s 44100' as most browsers will output sound at that samplerate
# '-p libs' tell gwion where to look for plugins
# '-d ws' use 'ws' (aka WebSocket) driver
# '$@' pass all arguments to gwion
echo './Gwion/gwion -s 44100 -p libs -d ws $@' > run.sh

A sound synthesis Hello World

The sound synthesis equivalent of hello world seems to be 5 seconds of a sine generator, at 440 hertz.

Let's just do that.

hello_sine.gw

#! Create a Sine generator and connect it to audio output
var SinOsc s => dac;
#! let five seconds pass
5::second => now;

test.sh

# do nothing without a BROWSER variable
if [ -z "$BROWSER" ]
then
  echo "please set BROWSER environment variable"
  exit 1
done
$BROWSER gwion_ws_test.html &!
bash run.sh hello_sine.gw

You might now see the test page in your browser.
Click the Connect button and you might here something! 🍾

More to come

Hopefully this post will get some support, and it'll motivate me to continue.
I think the second episode will demonstrate a simple but interesting psycho-acoustic experience,
and the third should show how to build a simple melody.
Since Gwion can obviously do so much more, there might be a ton of follow-up articles 😄

Building a project from markdown

Jérémie Astor — Sun, 27 Sep 2020 18:08:04 +0000

Building a project from markdown

This post is intented as an helper for my next one 😄

It aims to briefly demonstrate how one can use mdr
to build a project from a mdr file, which happens to be a markdown file
with few annotations.

Since I not yet comfortable with technical nor post writing,
I'm leaving a (hopefully commented) script do the explanation.
Please read before running 😄

# create a new directory and cd into it
mkdir GwionTest
cd GwionTest

# clone, build and install mdr
git clone https://github.com/fennecdjay/mdr
cd mdr
make
sudo make install

# get back to GwionTest directory
cd ..

# get the mdr file
curl https://raw.githubusercontent.com/fennecdjay/devto.sh/master/mdr/HelloGwion.mdr -o HelloGwion.mdr

# run mdr on the file, thus building the project
# set the BROWSER variable to the executable of the browser you use
# e.g: BROWSER=dissenter-browser mdr HelloGwion.mdr
BROWSER=<your browser here> mdr HelloGwion.mdr

I you see any issues with the wording or anything in this post or the mdr file,
please let me know.

How do you make banners for your posts?

Jérémie Astor — Sun, 27 Sep 2020 17:52:12 +0000

For this one and my next post I'm using this, thanks to a fellow DEV member, but last time I tried to do one myself, I got bad reviews (which were all pretty sensible).

I'd like to be able to have Gwion's logo and add text to it programmatically. Any idea how do that?

More important, what do you use?

EDIT: Changed the (missing) banner for one I made using canva.com, according to the suggestions.
The site is very usable, but doesn't seem to have an API, so I might change at one point.

How can I make my posts more discoverable?

Jérémie Astor — Wed, 16 Sep 2020 16:37:56 +0000

I'm asking this because my last post reached almost nobody. While most of the stuff I've been writing here is obviously low quality, I feel this particular post deserves some interest, and to be honest, I'm eager to get some feedback on this work.

Photo by Isaac Davis on Unsplash

A new syntax for Gwion!

Jérémie Astor — Wed, 16 Sep 2020 11:22:39 +0000

Syntax changes for Gwion

Check it here

I tried to address the syntax problems in Gwion.
Here's what I changed:

Declaration

Declarations needs a prefix

var
ref
nonnull
const
nonnull ref
const ref
const nonnull
const nonnull ref

This fixes the ambiguity of placement between const, nonnull and ref and makes it easy both for the reader and the parser to know when a variable is declared.

Also, there is no longer a need to use -> when declaring member types.

old syntax

class C {
  class D {}
}

C->D d;

new syntax

class C {
  class D {}
}

#! with the new 'var' modifier
var C.D d;

Acces Specifier

Attained consistency in placement.
Now it is always:
static or global or nothing
followed by
private or protect or nothing

Templates

improve template placement consistency: now always on the right.
change <~xxx~> to :[xxx]. shorter and can be packed Ptr:[:[int]Ptr] (before: <~<~int~>Ptr ~>Ptr with he space mandatory)

So now all template can be written xxx:[y,z]

new keyword: funcdef

to disambiguate with typedef used for type aliases.

Ability to fix functions

Inspired by a similar feature in haskell, you can now write

#! Automatic conversion to pointer for the first argument
#! default of value 1 for the second argument
fun int add(Ptr:[int] i, int j : 1) {
  return j +=> *i;
}

#! declare a variable
var int i;

#! traditionnal
<<< add(i,1)     >>>;

#! chuck style
<<< (i,1) => add >>>;

#! infix
<<< i @add 1     >>>;

#! prefix
<<< ($add) i     >>>;

#! postfix
<<< i $add       >>>;

Conclusion

I think that's all (well that and the usual bug fix here and there).

In my opinion, this is a huge improvement, but it's now up to you to tell me if there is something wrong, if you like it, whatever...

If nobody sees a problem with it, I'll merge next week.

Searching collaborators for a programming language

Jérémie Astor — Tue, 25 Aug 2020 18:31:48 +0000

I created a github organization to discuss development of Gwion, please contact me (and provide your github nick) if you're interrested.

What would be the simplest way to output sound to browser from a C program?

Jérémie Astor — Tue, 11 Aug 2020 11:07:49 +0000

Getting gwion to the browser

Some context

I made this progamming language to help in some of my musical projects. A few days ago I made a Repl. I think I have a way to provide drivers and libraries to it (leveraging github releases).

The problem

As of now, I have no driver that could send the sound to the browser. I guess I could easily hack something around libsndfile to provide say, a .wav, but it would really be better if I could have some realtime output to web-browser.

Do you have an idea?

So I'm asking here, as many DEV users have a good knowledge of web techniques and on my side I know, well, music and C.

Is replit tag broken?

Jérémie Astor — Sat, 08 Aug 2020 14:29:07 +0000

I just added Gwion to replit. Well, I had already done so, but now I leverage github releases, so it loads way faster.
I wanted to shared it on dev, as I have some remaining question, but it looks that the liquid tag for embedding replit is broken: on my machine, I can't see what I type ...
Is it just me or did I uncover some issue?

For sure one can check it here.

There's the mandatory hello world, that you can run

./gwion hello_world.gw

Maybe it is only broken in the preview, in which case I'll delete this post.

What is needed for easy onboarding?

Jérémie Astor — Sun, 26 Jul 2020 19:44:35 +0000

Pretty much everything in the title...

I need teammates for Gwion.

Currently there is also most no user doc, let alone the dev one. I just started adding doxygen comments to the util directory (not pushed yet), hoping it helps.

But maybe there is something I can do before that would be more useful.
What would you do?

Want to help development of a programming language?

Jérémie Astor — Thu, 23 Jul 2020 16:10:22 +0000

It's been a few years since I started developing my own programming language, because I loved chuck, but I felt it lacked at least generics and function pointers and performance was quite poor . As of today, Gwion is doing well in terms of features (even more than what I intented to have at first) and performance.

This niche project, IMHO, deserves some attention, and probably a community.

To prevent bus factor, I'm now searching people who would like to contribute. There is much left to do in the documentation area, but I'd also greatly appreciate discussion on its evolution.

Furthermore, there is this event coming, which I'd really like to be a part of, but I need teammates.

Thank you for reading this far (I know my english can be confusing at times).

What do you think? Would you join?

Correct order of programming concepts for a tutorial series

Jérémie Astor — Sat, 11 Jan 2020 15:22:06 +0000

I want to start a tutorial series for Gwion, accessible to beginners.

For those who don't know Gwion, it is an interpreted programming language, strongly typed, running on a stack VM and with a very strong relation to time, as its main use is sound/music generation.

Right now, I think it should start like:

Set things up: installing the language and libraries needed
Sequential programming: Just set up a sequence of instruction
Use functions: Put instructions in a function and use it instead. Leverage this post to demonstrate function overloading
Use your Own classes: Use a class instead of a function and demonstrate inheritance.

Later on will come templating for functions and classes, lambdas, functions pointers...

Does it seem correct for you?

If not, how would you order things?

Any advice will be greatly appreciated.