OSC module for Godot game engine
Switch branches/tags
Nothing to show
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.

README.md

gdosc

This is a Godot game engine module for receiving and sending Open Sound Control messages OSC. It uses oscpack as OSC protocol implementation so it potentially it works on all platforms that can handle oscpack. However it has been tested only on Linux (and, for the moment, I am not interested in any other platforms).

Installation

Godot engine

First, you will need the Godot engine sources. Head over to Godot compilation instructions to get Godot building on your system (make sure it can build with use_llvm=yes).

Then copy or link gdosc to godot/modules and recompile Godot with scons platform=x11

Dependencies

linux

If you wants to use clang, install it with:

sudo apt install clang

git

If you are not familiar with git, make sure it is installed:

sudo apt install git

Generate SSH key by following this tutorial and add it to your github account - HTTPS links are not working with submodules!

Once done, use these 2 commands to get the repo up & running:

git clone git@github.com:djiamnot/gdosc.git

git pull && git submodule init && git submodule update && git submodule status

It will retrieve oscpack submodule.

gdosc

Then, in your sources directory git clone --recurse-submodules https://github.com/djiamnot/gdosc and after that:

cd godot

ln -s <path/to/gdosc/ modules/

scons platform=x11 use_llvm=yes

Workflow

See gdosc-demo for an example on how to use these objects.

OSCreceiver - reception of OSC message in godot

First step is to add an OSCreceiver to your scene and configure it.

  • Port: number of the socket receiving messages;
  • Max Queue: maximum number of messages to keep in memory - can be seen as the maximum number of messages that might be received between 2 frames;
  • Autostart: set this to true to start the reception as soon as the scene starts;
  • Emit signal: set this to true to fire osc_message_received signals automatically.

If Emit signal is disabled, you have to parse received messages via a loop in * _process* (or any other method called regularly).

parsing messages at each _process

To do so, append a script to your OSCreceiver.

extends OSCreceiver

func _process(delta):
	while( has_waiting_messages() ):
		var msg = get_next_message()
		# the osc message is ready to be used at this point
		print( msg )

func _ready():
	set_process(true)
	pass

using signals

If Emit signal is enabled, at each NOTIFICATION_PROCESS, OSCreceiver will fire an osc_message_received signal. In order for OSCreceiver to receive notifications, you need to either add a _process method to the instance (even if it is empty) or call set_process(true) at an appropriate time, e.g. in the instance's _ready method.

To broadcast signals, you have to connect it to func of other objects. Let say that your scene is structured as follows:

  • root
    • OSCreceiver
    • MeshObject, with a script containing a func parse_osc(msg)
    • TextEdit, with a script containing a func dump_osc(msg)

To send messages to MeshObject and TextEdit, attach a script to OSCreceiver:

extends OSCreceiver

func _ready():
	connect( "osc_message_received", get_parent().get_node( "TextEdit"), "dump_osc" )
	connect( "osc_message_received", get_parent().get_node( "MeshObject"), "parse_osc" )
	set_process(true)
	pass

Important: Do mix retrieval methods! Why? All receveid messages are temporarily stored in a buffer. Retrieving a message from the buffer deletes it. As signals are fired after the execution of _process(), if you are mixing both retrieval methods, no message will be fired via signals. Indeed, all messages would already have been consumed by the * while* loop of the previous chapter.

OSCmessage

The object returned by get_next_message() or passed along with osc_message_received is an OSCmessage object.

Here are its gdscipt methods:

  • empty(): if true,there nothing in this message.
  • ip() : IP of the sender;
  • port() : port of the sender;
  • address() : the address of the message, looking like "/smthng/else";
  • typetag() : a list of characters specifying the type of each arguments received;
  • arg_num() : number of arguments in the received message;
  • arg(i) : returns the arguments at position i.

Example of script using a message:

func parse_osc( msg ):
	if ( msg.empty() ):
		return
	if ( !msg.ip() == "127.0.0.1" ):
		return
	if ( !msg.address() == "/pm/pos" ):
		return
	received_pos = Vector3( msg.arg(0),msg.arg(1),msg.arg(2))
	set_translation(received_pos)

OSCsender - emisson of OSC message from godot

First step is to add an OSCsender to your scene and configure it.

  • Ip: IP address of the computer to send messages to, 127.0.0.1 by default;
  • Port: number of the socket to send messages to;
  • Buffersize: maximum size of the messages sent from this object, in bytes;
  • Autostart: set this to true to start the emission as soon as the scene starts;
  • Autoclear: set this to true to cleanup the messages automatically after each call to msg_send().

If Autostart is disabled, you will have to call start() from gdscript before starting the emission.

If Autoclear is disabled, you will have call msg_clear() from gdscript. This can be usefull when the object is sending the same message continuously. In this case, configure the message once, then just call msg_send() to send it.

Checking the status of the object

You might need to test the status of the object from gdscript.

  • init(String, int): stops the emission and verify the validity of the IP address and the port (equivalent to is_ready());
  • is_ready(): returns true if the IP and the port are 'valid', meaning that the IP is not an empty string and the port is above 0, this does not test the connection;
  • is_started(): returns true the socket has been successfully binded, message emission is enabled if true.

Creating a message

Good practice involves setting the address of the message before adding values in it. But it makes no difference if you do it in reverse order.

List of methods available:

  • msg_address(String): set the address of the message, a / separated string, looking like /some/thing;
  • msg_add_int(int): append an int to the message;
  • msg_add_real(real): append an real (float or double) to the message;
  • msg_add_string(String): append a String to the message;
  • msg_add_v2(Vector2): append a Vector2 to the message, as a suite of real;
  • msg_add_v3(Vector3): append a Vector3 to the message, as a suite of real;
  • msg_add_quat(Quat): append a quaternion to the message, in W,X,Y,Z order;
  • msg_add_transform(Transform): append a complete Transform to the message, the matrix3x3 first, followed by the position;
  • msg_send(): sends the message if the object is successfullt started;
  • msg_clear(): clear the content of the previous message (done automatically after msg_send() if Autoclear is enabled).

Script sample:

extends OSCsender

var parent = null

func _process(delta):
	if (parent == null):
		return
	msg_address("/emitter/rot" )
	msg_add_quat( Quat(parent.global_transform.basis) )
	msg_send()

	msg_address("/emitter/pos" )
	msg_add_v3( parent.global_transform.origin )
	msg_send()

func _ready():
	set_process(true)
	pass

The parent of this OSCsender register itself as the parent at startup:

extends Spatial

func _process(delta):
	rotate_y( delta )
	pass

func _ready():
	set_process(true)
	get_node("OSCsender").parent = self
	pass

Contributing

Contributions are welcome. The preferred way to contribute is via pull requests. In order to do so, fork this repository, make a new branch based on the develop branch (or rebase onto develop when you are about to send a pull request) and when your fix/feature is ready, do a pull request against the develop branch. Master is reserved for stable releases.

Coding style

The c++ code in this repository uses the Google C++ Style Guide. .clang-format is included and you may find a configuration file for your editor here. It is also possible to use a git hook that will fix any style problems in your contribution automatically. In order to use the git pre-commit hook do the following (on Linux):

sudo apt-get install clang-format

#Then in .git folder:
rm -rf hooks && ln -s ../.hooks hooks