Toon Boom Harmony Integration

[tokejepsen]

Issue

This is about an Avalon integration for Toon Boom Harmony

This issue is to serve as a discussion for the integration.

Implementation

Harmony uses Qt Script which is a Javascript variant; https://docs.toonboom.com/help/harmony-17/scripting/script/index.html

[tokejepsen]

One of the issues with Harmony is the management of workfiles. A Harmony scene file is not a single file, but a folder of files and subfolders.

Read/writing lots of small files from the network has been reported as slow and taxing for the network.

A possible solution could be to wrap the scene folder up as a zip file. When using the workfiles app, we could manage this so in a project folder there are only zip files, but these get unpacked locally.

[tokejepsen]

Harmony has groups; https://docs.toonboom.com/help/harmony-16/essentials/layers/group-layers.html, so could possibly follow the #516 for creating instances.

[tokejepsen]

Harmony has a global scripts environment variable; https://docs.toonboom.com/help/harmony-16/essentials/scripting/store-script-custom-folder.html

[tokejepsen]

Interesting integration with Shotgun; https://github.com/diegogarciahuerta/tk-harmony

[tokejepsen]

Functions in TB_sceneOpened.js, TB_sceneOpenPreUI.js, TB_sceneCreated.js, TB_sceneAboutToClose.js are run as startup. These functions can be overridden with scripts in the environment variable: TOONBOOM_GLOBAL_SCRIPT_LOCATION.

[tokejepsen]

Got some progress on this. Have been taking the Shotgun integration apart to figure out the process;

This is the wrong way around with the server in Harmony and the client in Python, but at least the concept works.

[tokejepsen]

Menu

Since Harmony is built with Qt its surprisingly easy to add a menu.

[tokejepsen]

Think I have a two way communication planned out now:

• QTcpServer in Harmony listening to requests. A send_to_harmony method will be implemented on the Python side.
• QTcpServer in Python listening to requests. A send_to_python method will be implemented on the Harmony side.

This makes the communication standardized and you only have to understand either Qt Script (Javascript) or Python to know what is happening.

[tokejepsen]

Working Prototype

• The communication with Harmony is over a single connection; standard python server and QTcpSocket in Harmony. The port is randomized between 5000-6000 on each launch.

[tokejepsen]

Workfiles

The Workfiles app and workio code proved tricky and showed where the framework was failing. I ended up on a framework that looks similar to how pyblish-qml works:

+------------+
|            |
|   Python   |
|   Process  |
|            |
| +--------+ |
| |        | |
| |  Main  | |
| | Thread | |
| |        | |
| +----^---+ |
|     ||     |
|     ||     |
| +---v----+ |     +---------+
| |        | |     |         |
| | Server +-------> Harmony |
| | Thread <-------+ Process |
| |        | |     |         |
| +--------+ |     +---------+
+------------+

The server communicates over a single connection, same as in the previous post. The main difference from previous post, is that the server is threaded so communication with Harmony is still valid when the main thread is busy with for example showing a GUI.

Another issue was with how Harmony opens scenes. I'm still querying this with support but it seems like you can only open a new scene by launching a new process. To make this work with the Workfiles I'm killing the Toon Boom process and the server thread, then starting new ones.

[tokejepsen]

Forgot to mention that I've also "hacked" the Workfiles app so Harmony project folders are saved as zip files on the network. When loading zip workfiles, they get unpacked and opened.

[tokejepsen]

Saving

Because I'm "hacking" the Workfiles app to zip a project directory, I've also needed to have a callback when the user is saving the scene.
In Harmony there aren't any callbacks for saving a scene, but can watch the scene file for changes with QFileSystemWatcher.

function on_file_changed_callback()
{
  var self = this;

  // Attach the client to the QApplication to preserve.
  var app = QCoreApplication.instance();

  // Watch scene file for changes.
  self.on_file_changed = function(path)
  {
    var app = QCoreApplication.instance();
    MessageLog.trace(path);
    app.watcher.addPath(path);
  }

    app.watcher = new QFileSystemWatcher();
    scene_path = scene.currentProjectPath() +"/" + scene.currentVersionName() + ".xstage";
    app.watcher.addPath(scene_path);
    app.watcher.fileChanged.connect(on_file_changed);
}

The zipping and move (locally) can take as long as the saving, so in order to reduce user impact, we just thread off this so it happens in the background.

Create

Have opted for composite nodes in Harmony since you can connect any number of nodes simultaneously to composites.
For imprinting and metadata, we can create attributes on the nodes which is currently named "avalon". This holds a json serialized dictionary.

Also found out that *.xstage files are xml formatted, so you can inspect this metadata with text editor.

[tokejepsen]

Publishing

Still querying whether is a way to script the rendering of the write nodes without the dialog.