godot-pd

GDExtension that allows you to interact with and run Pure Data patches in Godot.

Currently uses Pd vanilla version 0.56-1.

Latest tested Godot version: 4.5 stable.

Installation

Download the latest release from the release page, then copy the addons/ folder to your Godot project's root folder.

You can also build from source.

Overview

To begin using the extension, assign an AudioStreamPD resource to an AudioStreamPlayer's stream property in the inspector. For more details, please see the in-editor documentation for both AudioStreamPlaybackPD and AudioStreamPD.

Here's some sample code:

@onready var player: AudioStreamPlayer = $AudioStreamPlayer

var pd: AudioStreamPlaybackPD

func _ready():
    # setup
    player.play()
    pd = player.get_stream_playback()
    
    # playing patches
    pd.open_patch("example.pd")

    # sending messages
    pd.send_bang("start-loop")
    pd.send_float("set-pitch", 440)

    # receiving messages
    pd.subscribe("my-tag")

    pd.receive_bang.connect(_on_receive_bang)
    pd.receive_float.connect(_on_receive_float)

func _on_receive_bang(dest: String):
    # do something...

func _on_receive_float(dest: String, num: float):
    # do something with num...

Issues and Limitations

• Sometimes, trying to open an invalid or missing patch file with AudioStreamPlaybackPD.open_patch() will cause a crash. This is probably related to libpd issue #372, although I have not been able to reproduce this consistently.
• It's not possible to access patch files directly from res:// with this extension. You will need to access them using regular file system paths. As a result, when exporting you will need to manually move patch files into your export folder as it will not be possible to access them from the exported PCK.

Building from source

# on macOS
./dev.macos.sh