Multitouch GTK3 Example - multi-touch

From what I understand, multitouch support was added to GTK+ as of version 3.4. What I'm not clear on is whether this applies just to touch screens like phones/tablets or whether it extends to Apple style touch pads (the way Ubuntu/Unity and OS X use multitouch gestures on the touchpad).
I've also had a hard time finding examples of how to implement gestures and how to track multitouch events.
Are there any good examples of how to implement multitouch with GTK (or something related like Clutter)?

I also couldn't find examples so here is my knowledge about it:
Mouse events (introduction):
When using mouse Gdk propagates events GDK_BUTTON_PRESS, GDK_BUTTON_RELEASE (and a few other). That gets translated into GtkWidget signals like button-press-event and then into higher level ones like GtkButton's clicked if applicable. Connecting a callback to the button-press-event signal allows access to GdkEventButton structure. Using clicked however frees you from keeping track whether it was a click (press & release) or only a release (during kinetic scrolling for instance).
Touch events:
Touch works a little bit different. There are 4 touch events:
GDK_TOUCH_BEGIN
A new touch event sequence has just started. This event type was added
in 3.4.
GDK_TOUCH_UPDATE
A touch event sequence has been updated. This event type was added in
3.4.
GDK_TOUCH_END
A touch event sequence has finished. This event type was added in 3.4.
GDK_TOUCH_CANCEL
A touch event sequence has been canceled. This event type was added in
3.4.
and GdkEventTouch structure uses GdkEventSequence for differentiating between fingers. It seems to me that it is simply a value (couldn't find definition in the sources) but I may be mistaken here. GtkWidget has touch-event signal similar to button-press-event etc that also gets translated into events like clicked.
Sample code (using gtkmm but core aspects are the same):
#include <gtkmm.h>
#include <iostream>
int main()
{
auto app = Gtk::Application::create();
Gtk::Window window;
window.set_default_size(1024, 768);
app->signal_startup().connect([&]
{
app->add_window(window);
});
window.show();
//code works for me without adding events mask but let's be thorough
window.add_events(Gdk::TOUCH_MASK);
window.signal_touch_event().connect([&](GdkEventTouch* event)->bool
{
std::cout<<"TOUCH EVENT: ";
switch(event->type)
{
case GDK_TOUCH_BEGIN:
std::cout<<"begin ";
break;
case GDK_TOUCH_UPDATE:
std::cout<<"update ";
break;
case GDK_TOUCH_END:
std::cout<<"end ";
break;
case GDK_TOUCH_CANCEL:
std::cout<<"cancel ";
break;
default:
std::cout<<"something else ";
}
std::cout<<event->sequence<<" "
<<gdk_event_get_event_sequence((GdkEvent*)event)<<" "
<<std::endl;
return GDK_EVENT_PROPAGATE;
});
window.signal_event().connect([&](GdkEvent* event)->bool
{
std::cout<<"EVENT: "<<event->type<<std::endl;
return GDK_EVENT_PROPAGATE;
});
app->run();
return 0;
}
Touchpad events:
There are also touchpad & pad events and structures but it seems that there is no explicit handling of these on Gtk level. It has to be done in callback for event signal with checking GdkEventType and casting it into appropriate structures.

Related

How to integrate Hand Controlle HC1 in my car simulator game

I m building a car simulator game using Unity. For the input I m using Logitheck steering wheel G29. Now I need to use Hand Controller to accelerate or break.
This is my Hand Controller
Hand Controller HC1
Link
Now I can I interpect his input ? This device is recognize by my windows 10 system, but if I try to start the game with this device I cannot accelerate or break the car.
I configured this in my InputController of Unity:
And in my IRDSPlayerControls.cs file I write these lines of code:
if (Input.anyKey)
{
foreach (KeyCode kcode in Enum.GetValues(typeof(KeyCode)))
{
Debug.Log("Joystick pressed " + kcode);
}
}
Debug.Log("Input debug acc: " + Input.GetAxis("Vertical3"));
Debug.Log("Input debug frenata: " + Input.GetAxis("Vertical4"));
In Console of Unity, I can display this:
Input debug acc: -1
Input debug frenata: -1
You can detect a specific button on a specific joystick joystick 1 button 0, joystick 1 button 1, joystick 2 button 0…
or a specific button on any joystick joystick button 0, joystick button 1, joystick button 2…
Check out Input Manager
I can explain this step by step here but it wont be as good as some tutorials online. I recommend this video as a good tutorial to do this.
UPDATE:
I think your hand controller give analog values and the acceleration/brake buttons are not actually buttons but they are analog joy sticks and have a range of values.
to check this use Input.GetJoystickNames :
using UnityEngine;
public class Example : MonoBehaviour
{
// Prints a joystick name if movement is detected.
void Update()
{
// requires you to set up axes "Joy0X" - "Joy3X" and "Joy0Y" - "Joy3Y" in the Input Manager
for (int i = 0; i < 4; i++)
{
if (Mathf.Abs(Input.GetAxis("Joy" + i + "X")) > 0.2 ||
Mathf.Abs(Input.GetAxis("Joy" + i + "Y")) > 0.2)
{
Debug.Log(Input.GetJoystickNames()[i] + " is moved");
}
}
}
}
I will suggest to first check if those inputs are being received with:
if (Input.anyKey)
{
foreach(KeyCode kcode in Enum.GetValues(typeof(KeyCode)))
{
Debug.Log(kcode);
}
}
This way you can know if the game is recognizing the keycodes of your controller, and if it does, which names are assigned to them.
Once you got this, you only need to check keycodes as an usual keyboard!
Not every joystick, steer etc. is mapping it's inputs to the same axis.
There is a unity forum about that topic (and other related problems). And I found that there are some unity plugins, that could probably solve your problem:
https://github.com/speps/XInputDotNet
https://github.com/JISyed/Unity-XboxCtrlrInput
There are some programs that you can use to list all input axis and see which one you are currently affecting. I used one of them but don't remember the name of it. It might help you to see to which axis your break and throttle are mapped to.
Some of them also allow you to remap then, if this is what you want.
The most probable cause is Unity3D does not support this device.
Unity3D uses a mix of XInput, GameInput?, and USB HID processing for its input on Windows.
It is unclear(closed source), if GameInput is used on Windows, it is required on the modern XBOX's.
I cannot provide a definitive answer, since I do not have this controller to test, and the documentation on the controller is sparse.
The best I can do is point you in the right direction.
Does the device exist in Unity3D:
See if the Input System identifies the device when plugged in while running (make sure the game window has focus):
Adapted from https://docs.unity3d.com/Packages/com.unity.inputsystem#1.4/manual/HowDoI.html
InputSystem.onDeviceChange +=
(device, change) =>
{
switch (change)
{
case InputDeviceChange.Added:
// New Device.
Debug.Log("New device added.");
break;
case InputDeviceChange.Disconnected:
// Device got unplugged.
break;
case InputDeviceChange.Connected:
// Plugged back in.
break;
case InputDeviceChange.Removed:
// Remove from Input System entirely; by default, Devices stay in the system once discovered.
break;
default:
// See InputDeviceChange reference for other event types.
break;
}
}
A lack of log output, when plugged in means the device was not identified as a potential input device. Skip to "All else Fails" below.
Identification at this level does not imply support, as it may flag all HID devices.
Look at all low level input events while pressing the buttons:(Also adapted from 4)
var trace = new InputEventTrace(); // Can also give device ID to only
// trace events for a specific device.
trace.Enable();
//…run stuff
var current = new InputEventPtr();
while (trace.GetNextEvent(ref current))
{
Debug.Log("Got some event: " + current);
}
// Trace consumes unmanaged resources. Make sure to dispose.
trace.Dispose();
The chances of getting here with responses(given the edited output) are slim, but if it happens explore the output to find hints to the device associations and fix your mappings accordingly.
All else Fails
Request device support though Unity3D.com website. Highly recommended.
You can write your own support for the device using either the USB HID, may be flagged by virus scanners, and there is limited documentation or implement a custom GameInput interface. The inclusion in Windows Game Controllers makes this the most probable solution.

Intercept X11 KeyPress event in GtkDrawingArea of GTK+3 on Linux

GTK+ version: 3.18.9
I created a drawing area (GtkWidget) with following code
content = gtk_drawing_area_new();
gtk_widget_set_can_focus(content, TRUE);
gtk_widget_add_events(content, GDK_ALL_EVENTS_MASK);
g_signal_connect(content, "draw", G_CALLBACK(&drawCallback), ctx);
gtk_widget_realize(content);
// Add a filter for interception
gdk_window_add_filter(content, gtk_widget_get_window(content),
OnXEvent, NULL);
Problem is that when I clicked the wideget, I got sequence of XEvents as follows:
LeaveNotify
FocusIn
EnterNotify
ButtonPress
FocusOut // Lost focus!
ButtonRelease
Above FocusOut indicated we lost focus right away after clicking.
It implies we can't receive any keyboard events since they are available only within focus.
Is this limitation of GTK? If not, is there any tools/methodlogy to find out which widget/widow trigger the FocusOut?
References:
gdk_window_add_filter
As of GTK+ version 3.18.9, it uses an extra X window for toplevel window and any keyboard events are captured by the window. Thus a filter need to be added as a global one, i.e.
gdk_window_add_filter(NULL, OnXEvent, NULL)
Note that the API was removed in this commit in GTK+ 4.x.

Gstreamer 1.0 Pause signal

I need to detect when the current playing audio/video is paused. I cannot find anything for 1.0. My app is a bit complex but here is condensed code
/* This function is called when the pipeline changes states. We use it to
* keep track of the current state. */
static void state_changed_cb(GstBus *bus, GstMessage *msg, CustomData *data)
{
GstState old_state, new_state, pending_state;
gst_message_parse_state_changed(msg, &old_state, &new_state, &pending_state);
if(GST_MESSAGE_SRC(msg) == GST_OBJECT(data->playbin))
{
g_print("State set to %s\n", gst_element_state_get_name(new_state));
}
}
gst_init(&wxTheApp->argc, &argv);
m_playbin = gst_element_factory_make("playbin", "playbin");
if(!m_playbin)
{
g_printerr("Not all elements could be created.\n");
exit(1);
}
CustomData* data = new CustomData(xid, m_playbin);
GstBus *bus = gst_element_get_bus(m_playbin);
gst_bus_set_sync_handler(bus, (GstBusSyncHandler) create_window, data, NULL);//here I do video overly stuffs
g_signal_connect (G_OBJECT (bus), "message::state-changed", (GCallback)state_changed_cb, &data);
What do I do wrong? I cannot find working example on connecting such events on Gstreamer 1.0 and 0.x seems a bit different than 1.0 so the vast exaples there don't help
UPDATE
I have found a way to get signals. I run wxWidgets timer with 500ms time span and each time timer fires I call
GstMessage* msg = gst_bus_pop(m_bus);
if(msg!=NULL)
{
g_print ("New Message -- %s\n", gst_message_type_get_name(msg->type));
}
Now I get a lot of 'state-change' messages. Still I want to know if that message is for Pause or Stop or Play or End of Media (I mean way to differentiate which message is this) so that I can notify the UI.
So while I get signals now, the basic problem, to get specific signals, remains unsolved.
You have to call gst_bus_add_signal_watch() (like in 0.10) to enable emission of the signals. Without that you can only use the other ways to get notified about GstMessages on that bus.
Also just to be sure, you need a running GLib main loop on the default main context for this to work. Otherwise you need to do things a bit different.
For the updated question:
Check the documentation: gst_message_parse_state_changed() can be used to parse the old, new and pending state from the message. This is also still the same as in 0.10. From the application point of view, and conceptionally nothing much has changed really between 0.10 and 1.0
Also you shouldn't do this timeout-waiting as it will block your wxwidget main loop. Easiest solution would be to use a sync bus handler (which you already have) and dispatch all messages from there to some callback on the wxwidget main loop.

QApplication::processEvents never returns

In my application I need to wait until external program (using QProcess) is finished. I want to keep the application responsible so blocking methods are unacceptable.
Also I need to disallow user input. I've tried to make QEventLoop and exec it with QEventLoop::ExcludeUserInputEvents flag, but as documentation says it only delays an event handling:
the events are not discarded; they will be delivered the next time processEvents() is called without the ExcludeUserInputEvents flag.
So I implemented simple event filter and install it on qApp (the idea is took from Qt Application: Simulating modal behaviour (enable/disable user input)). It works well, but sometimes QApplication::processEvents function never returns even if I specify the maximum timeout. Could anyone help me to understand for what reasons it periodically happens?
class UserInputEater : public QObject
{
public:
bool eventFilter(QObject *object, QEvent *event)
{
switch(event->type())
{
case QEvent::UpdateRequest:
case QEvent::UpdateLater:
case QEvent::Paint:
return QObject::eventFilter(object, event);
default:
return true;
}
}
};
-
UserInputEater eventEater;
qApp->installEventFilter(&eventEater);
QProcess prc;
prc.start("...");
while(!prc.waitForFinished(10))
{
if(qApp->hasPendingEvents())
{
// Sometimes it never returns from processEvents
qApp->processEvents(QEventLoop::AllEvents, 100);
}
}
qApp->removeEventFilter(&eventEater);
UPD: Seems like it depends of the timeout value for QProcess::waitForFinished.
I guess you are filtering some useful events (for example, QEvent::SockAct could be involved). Try to add some debug output and find out which event types you're actually filtering. Or it might be better to specify the black list of events you want to block instead of white list of events you want to allow. See this answer.
Also you shouldn't use return QObject::eventFilter(object, event);. You should use return false. All other event filters will be called automatically.
This solution however seems weird and unreasonable to me because you can just call setEnabled(false) for your top level widget to block user input, and then you can use QApplication::processEvents without any flags.

Simulate mouse on Mac

I have a virtual trackpad on my iPhone and to move my mouse I'm using :
CGDisplayMoveCursorToPoint(kCGDirectMainDisplay, CGPointMake(((float)aD.msg)+location.x, ((float)aD.msg2)+location.y));
It's working well but this not a real mouse because when I put my mouse on my hidden dock, this one doesn't display it self. I don't understand why.
More over I tried to simulate mouse click with :
case MOUSECLICK:
[self postMouseEventWithButton:0 withType:kCGEventLeftMouseDown andPoint:CGEventGetLocation(CGEventCreate(NULL))];
[self postMouseEventWithButton:0 withType:kCGEventLeftMouseUp andPoint:CGEventGetLocation(CGEventCreate(NULL))];
// *********************
-(void)postMouseEventWithButton:(CGMouseButton)b withType:(CGEventType)t andPoint:(CGPoint)p
{
CGEventRef theEvent = CGEventCreateMouseEvent(NULL, t, p, b);
CGEventSetType(theEvent, t);
CGEventPost(kCGHIDEventTap, theEvent);
CFRelease(theEvent);
}
Is it the good method? Thanks for your help !
CGDisplayMoveCursorToPoint() only moves the image of the cursor, it does not generate any events. You should create and post mouse events of type kCGEventMouseMoved to simulate moving the mouse. Your own method would do it:
[self postMouseEventWithButton:0 withType:kCGEventMouseMoved andPoint:point];
For clicks, you are already doing it the right way, I think. One thing you should also do is set the click count properly on both the mouse down and mouse up events, like so:
CGEventSetIntegerValueField(event, kCGMouseEventClickState, 1);
... because some applications need it.
(See also Simulating mouse clicks on Mac OS X does not work for some applications)
If your code doesn't work, I'm not sure why; it looks OK to me. Try posting to kCGSessionEventTap instead of kCGHIDEventTap and see if it helps. Also, you don't need the CGEventSetType() call since the type is already set in the creation call.