Tag: zest

Multitouch gesture support for Zest graphs

When I read Jan Köhnlein’s post about multitouch gestures support in their graph viewer, I was thinking, these gestures would be a nice addition to the Zest visualization library. In addition to that, it could be my first new feature as a Zest committer, so I opened bug 371152.

So I looked into the multitouch API in SWT (btw. it is really to use, check snippet 353). Luckily, only a gesture listener had to be added, that is already supported by the Zest graph widget.

I thought about what gestures could be universally supported in the Zest graph, and found that scrolling is already supported, magnification is easy to implement, and for rotation I found a possible use.

Today, I finished the implementation, and created a short video presentation that shows the features in action. See the Youtube video: http://youtu.be/cVVxOIwHN7s

Additionally, it is possible to replace the built-in gestures by creating the graph with a specific style bit, and adding other gesture listeners manually as below:

//Disabling default gestures
Graph graph = new Graph(parent, ZestStyles.GESTURES_DISABLED);
//Adding own gesture listener
graph.addGestureListener(new GestureListener() {

  public void gesture(GestureEvent e) {
    switch (e.detail) {
      // Do nothing
    }
  }
});

I believe the base implementation of the gesture support is useful, but I am open to change it if someone has a better idea.

Source code visualisation for my projects

Today I read the announcement of SourceCloud, a new Zest/Cloudio-based visualization for source code. As I like cool visualizations, I tried it out on the open projects I am participating in.At first I created the cloud for the source code of the Debug Visualisation project. Globally it consists of about half Eclipse debugger/UI and Java keywords – as this is quite a small project (about 4 kLOC), this is somewhat expected with 200 words.

SourceCloud of the Debug Visualisation Project

However, it is interesting, that the strings ‘end_of_line‘ and ‘sp_cleanup‘ found their way in. Luckily, only a few one-character names and numbers are present, meaning, we managed to created longer variable names…

The cloud of the VIATRA2 model transformation framework is more interesting: it is a much larger codebase, developed for several year by around a dozen people. Because of the size I generated the cloud using 300 words, but almost no Java keywords found their way into the graph.

SourceCloud of the VIATRA2 framework

However, the mandatory comment parts did, e.g. nbsp or the names of some creators. A lot of EMF-specific keywords are also present. They are present because we have quite a large EMF metamodel that provides several hundred generated Java files.

At last, but not least I also checked the cloud of the EMF-IncQuery project. This is smaller, then the VIATRA2 project, but larger then the Debug Visualisation. Additionally, it has a shorter history, but with several key committers.

SourceCloud of the EMF-IncQuery project

My personal favorite is this diagram, as it shows a lot of nice things: e.g. four digit numbers in large quantities (magic numbers FTW) or the absolute champion string: ‘HUKfyM7ahfg‘. All of them are present in the Ecore Diagram of the defined metamodel (the meaningless string 152 times as a postfix of an identifier 🙂 ). At least, I learned something about the internal model representation of GMF.

And how do your projects look like?