Cool! I'll test it on my macbook later on. You've got your dev account now, btw, just got the mail from the sysadmins!

You mean touchpad gesture support, not touch (as in touchscreen) support, right? Or are the two mixed together on OS X?

I'll check whether it breaks current touchscreen support on Windows. I don't think Qt supports the precision touchpad on Windows but I will try it too...

Was two finger pan and zoom already working with the existing touch gesture code?

Got this while compiling on Windows, not sure if related to this patch or not...

[ 43%] Linking CXX shared library ..\..\bin\libkritaui.dll
CMakeFiles\kritaui.dir/objects.a(kis_input_manager.cpp.obj): In function `KisInputManager::profileChanged()':
F:/dev/krita/new/src/libs/ui/input/kis_input_manager.cpp:666: undefined reference to `KisInputManager::Private::addNativeGestureShortcut(KisAbstractInputAction*, int, KisShortcutConfiguration::GestureAction)'
F:/dev/krita/new/src/libs/ui/input/kis_input_manager.cpp:666:(.text+0xf28): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `KisInputManager::Private::addNativeGestureShortcut(KisAbstractInputAction*, int, KisShortcutConfiguration::GestureAction)'
collect2.exe: error: ld returned 1 exit status
mingw32-make[2]: *** [libs\ui\CMakeFiles\kritaui.dir\build.make:10112: bin/libkritaui.dll] Error 1
mingw32-make[1]: *** [CMakeFiles\Makefile2:16246: libs/ui/CMakeFiles/kritaui.dir/all] Error 2
mingw32-make: *** [Makefile:140: all] Error 2

@alvinhochun Yes, pan and zoom are implemented, but on OS X, pan actually maps to zoom as it is reported as a mouse wheel event by Qt, it's very confusing, and zoom works but not, touch wise, as reliable as the native gestures.

Yes, only touchpad, no touchscreen support, though I would hope some day this API might be used to connect to the touch features of Wacom Intuos and Cintiqs as well.

Confirmed that this patch doesn't break existing touch gestures on Windows, and that the "precision touchpad" isn't supported here.

It's funny because I started reading about gesture support in Qt two days ago and was thinking of the possibility of re-implementing the touchscreen gestures with QPinchGesture, and then you submitted this patch adding yet another way of handling gestures... except it only works on OS X...

@alvinhochun I should have mentioned that it's not really enabled for other platforms as I didn't want to break anything. You can try to commend out the two #ifdef Q_OS_OSX and see what happens; it then will override Krita's implementation. But if QT does not send any QNativeGestureEvents on specific platform, this basically breaks touch support for the platform.

In D8121#152068, @poke1024 wrote:

@alvinhochun I should have mentioned that it's not really enabled for other platforms as I didn't want to break anything. You can try to commend out the two #ifdef Q_OS_OSX and see what happens; it then will override Krita's implementation. But if QT does not send any QNativeGestureEvents on specific platform, this basically breaks touch support for the platform.

Does this mean this patch might break proper touchscreen support on OS X?

@alvinhochun I believe not. First, the code only overrides multi finger gestures, not single finger touch inputs. And this is done by processing the QNativeGestureEvent that Qt gives us. The classic Krita touch implementation of those touch events that are detectable using QNativeEventGestures under OS X is only deactivated because there would be a conflict otherwise: for pinch and rotate, Qt sends a QNativeEventGestures as well as a QTouchEvent, which means Krita would process the same gesture twice with different code paths, which is obviously not desirable. A similar thing happens with pan events (they come as QWheelEvent as well as QTouchEvent on OS X). So, the only reason some code paths are overriden is to not handle the same gesture twice. We might of course do something like: if a QNativeGestureEvent arrives, then ignore all following or near QTouchEvents; but that would assume that the QNativeGestureEvent always comes first and the QTouchEvents for the same physical finger movement comes second, and that is not documented in Qt. So it's a bit difficult how to really deal with this cross platform wise, if one does not know which events the platform will give us. On OS X it's simple. But on other systems this might have to be an option like "Enable native gesture events".

I wonder if using QNativeGestureEvent for pan, zoom and rotate makes sense for other platforms as well.

In D8121#152336, @poke1024 wrote:

But on other systems this might have to be an option like "Enable native gesture events".

Couldn't your implementation be disabled by default and be enabled the first time a QNativeGestureEvent is received?
This way it would be enabled on all systems that support these events.

I kind of think it might be better to just handle all touch gestures by Krita itself, this way we can have more fine-grained control on how touch interaction works.
(I have some ideas but I need to first write them down.)

I am compiling a version to test if QNativeGestureEvent works on Windows, but I don't think Qt supports it.

Hm, I have some trouble actually using gestures other than zoom on the touchpad of my macbook pro (2015) -- I'm not sure how to activate panning and rotating...

Tested, doesn't work on Windows.

It looks like QTouchEvent::device() returns QTouchDevice and QTouchDevice::type() can be used to differentiate touchscreen and touchpad events (though really only seem to be useful on OS X atm). Can you perhaps use it to allow touchscreen gestures on OS X?

@alvinhochun I'm not sure there are many ways to use OS X with a touch enabled screen. I have a touch enabled Wacom Cintiq but their touch drivers are unfortunately just a hack mapping to certain keyboard shortcuts and they seem completely separate from Apple native touch events you get from using a MacBook trackpad, so no QNativeGestureEvents here.

Oh no, clearly I have no idea how bad touchscreen support on OS X is. I'm just worried there will be a regression, but it sounds like there won't be any then.

I haven't seen any visible regressions on Linux

One acceptance is enough I think, formally.

pushed.
https://commits.kde.org/krita/cbb6ed2daa053715aeba943eba78bde31c0d6e39

We should document somewhere that Mac users need to delete/update their local kritadefault.profile (usually under Application Support/krita/input) in order for this to work as the new modified kritadefault.profile needs to be fetched.

Hi @poke1024, your commit is missing the new files :(

@alvinhochun @rempt pushed again, sorry for that :-(

https://commits.kde.org/krita/9e9789d4ca44960c3e13d89a411377fbe1022ce8