How can I disable arbitrary default multitouch gestures in Unity?

Question

I'm using a custom Touchégg multitouch gesture setup in Ubuntu 11.04 with a Magic Trackpad. Since the default gestures (such as 3-finger tap and drag to move windows, 4 finger tap to reveal the dash, etc.) are apparently hardcoded in Unity, I'm unable to assign any custom Touchégg actions to them, and some default gestures (that I don't intend to use much, if at all) occasionally mix up with my similar custom-assigned ones and get triggered by accident.

Is there a practical way (short of tweaking the uTouch source) to disable some of the default gestures? If not, pointers to parts of the code (perhaps in grail?) where the default gestures are defined, and help with tweaking would also be appreciated.

Answer 1

An update to domster answer for Ubuntu 12.10.

Unity source code has obviously changed, so here is how to achieve the same in Unity 6.8.0. The steps to download Unity source code are the same as before (I will copy & paste domster's snippet):

sudo apt-get build-dep unity
cd /tmp  #It can be done somewhere else, feel free to change the base location.
mkdir unity
cd unity
apt-get source unity

At this point, the file to be edited is only /tmp/unity/unity-6.8.0/plugins/unityshell/src/unityshell.cpp.

Find the method UnityScreen::InitGesturesSupport() (line 3368 for Unity 6.8.0).

Then, comment all the lines starting with gesture_sub_launcher to make it look like:

void UnityScreen::InitGesturesSupport()
{
  std::unique_ptr<nux::GestureBroker> gesture_broker(new UnityGestureBroker);
  wt->GetWindowCompositor().SetGestureBroker(std::move(gesture_broker));
  /*
  gestures_sub_launcher_.reset(new nux::GesturesSubscription);
  gestures_sub_launcher_->SetGestureClasses(nux::DRAG_GESTURE);
  gestures_sub_launcher_->SetNumTouches(4);
  gestures_sub_launcher_->SetWindowId(GDK_ROOT_WINDOW());
  gestures_sub_launcher_->Activate();

  gestures_sub_dash_.reset(new nux::GesturesSubscription);
  gestures_sub_dash_->SetGestureClasses(nux::TAP_GESTURE);
  gestures_sub_dash_->SetNumTouches(4);
  gestures_sub_dash_->SetWindowId(GDK_ROOT_WINDOW());
  gestures_sub_dash_->Activate();

  gestures_sub_windows_.reset(new nux::GesturesSubscription);
  gestures_sub_windows_->SetGestureClasses(nux::TOUCH_GESTURE
                                         | nux::DRAG_GESTURE
                                         | nux::PINCH_GESTURE);
  gestures_sub_windows_->SetNumTouches(3);
  gestures_sub_windows_->SetWindowId(GDK_ROOT_WINDOW());
  gestures_sub_windows_->Activate();
  */
}

Re-build Unity following domster's instructions again:

cd /tmp/unity/unity-6.8.0
dpkg-buildpackage -us -uc -nc
cd ..
sudo dpkg -i *deb

Et voila again! Logout and log back in.

Answer 2

It turns out that it is not that hard to patch the unity package for totally disabling its handling of multi-touches and gestures. Here are step by step instructions for patching unity-4.24.0.

In a command line, enter:

sudo apt-get build-dep unity
cd /tmp  #It can be done somewhere else, feel free to change the base location.
mkdir unity
cd unity
apt-get source unity

At this point, comment out the following 2 lines in the file /tmp/unity/unity-4.24.0/plugins/unityshell/src/unityshell.cpp:

GeisAdapter::Default()->Run();
gestureEngine = new GestureEngine(screen);

and the following 4 lines in the file /tmp/unity/unity-4.24.0/plugins/unityshell/src/Launcher.cpp:

GeisAdapter& adapter = *(GeisAdapter::Default());
adapter.drag_start.connect(sigc::mem_fun(this, &Launcher::OnDragStart));
adapter.drag_update.connect(sigc::mem_fun(this, &Launcher::OnDragUpdate));
adapter.drag_finish.connect(sigc::mem_fun(this, &Launcher::OnDragFinish));

The source code is in C++, so commenting a line is done by adding // at the beginning of the line. For instance, the line

GeisAdapter::Default()->Run();

becomes

//GeisAdapter::Default()->Run(); .

Back to the command line, enter:

cd unity-4.24.0
dpkg-buildpackage -us -uc -nc
cd ..
sudo dpkg -i *deb

Et voila!

Now if you logout and log back in, gestures should function normally. Triple tap works on my system as a middle click by default, without a need for touchegg. But both touchegg and ginn now work well to define custom gestures for your applications.

Answer 3

To do this on latest unity (5.18.0) in 12.04 you have to comment-out slightly different code lines.

In plugins/unityshell/src/Launcher.cpp:

// GeisAdapter& adapter = GeisAdapter::Instance();
// adapter.drag_start.connect(sigc::mem_fun(this, &Launcher::OnDragStart));
// adapter.drag_update.connect(sigc::mem_fun(this, &Launcher::OnDragUpdate));
// adapter.drag_finish.connect(sigc::mem_fun(this, &Launcher::OnDragFinish));

In plugins/unityshell/src/unityshell.cpp:

// geis_adapter_.Run();
// gesture_engine_.reset(new GestureEngine(screen));

Answer 4

Second try

dinegri suggest that ' [t]o disable three gestures, it [is] necessary [to] have installed ccsm, [and then] disable "Unit MT Grab Handles" also know as "Loves Handles" ' here.

But it leaves us with the four finger gestures yet.

First try

The configuration file for utouch is /etc/ginn/wishes.xml. So you can edit this file and remove (or comment) the actions you don't want. Then Touchégg would do its job without conflicts.

Reference

PS: I couldn't reproduce your problem here to test the solution. I'm sorry for that.

Answer 5

Disable standard touch gestures as follows:

sudo apt install dconf-editor
dconf-editor

In the left-hand menus click to

com > canonical > unity > gestures

and disable the 3 basic gestures shown there. This works on 16.04.3.

Answer 6

We've built a Ubuntu based kiosk terminal, but the multitouch gestures revealed the OS, so we had to get rid of that somehow.

It was a Samsung touchscreen device, xinput identified the touch module as AFO TCM10J 40V.

To disable multitouch gestures on Ubuntu 14.04 the method is basically the same as domster described above, except you have to find an comment the following row in /tmp/unity/unity-4.24.0/plugins/unityshell/src/Launcher.cpp

// InitGestureEngine();

Answer 7

Note that dpkg-buildpackage can be given number of jobs as argument, which allows you to use all your CPU cores like this:

dpkg-buildpackage -us -uc -nc -j$(($(nproc)))

(This should have been a comment to dgraziotin's answer, but I can't post comments.)