XI2 provides us with an increment for each scroll valuator,
and by dividing the delta by the increment, we obtain normalized
values in some abstract 'scroll unit'.
For mouse wheels, the evdev driver reports an increment of -1,
so doing this division fixes the inverted scrolling with wheels
that we've seen recently.
XInput >= 2.1 allows for implementing smooth scrolling,
reporting the different scrolling axes as valuators.
Any change in those will be reported as GdkEventScroll
events with delta_x/y information.
the older kind of scroll events is still handled, and
emulated in devices able to provide smooth scrolling,
setting _gdk_event_set_pointer_emulated() in that case.
Translate XI_TouchBegin/Update/End to GDK_TOUCH_BEGIN/UPDATE/END
events.
At the same time,
set pointer-emulated flags on button events with XIPointerEmulated
and on touch events emulating the pointer.
This function can be used to find out the XInput2 device ID
behind a GdkDevice, mostly useful when you need to interact
with say Clutter, or raw libXi calls.
_gdk_device_get_axis_use() dates back to pre-sealing, when the
xi2 work began, this remaining can be gone with a public
gdk_device_get_axis_use() function already in place.
Previously we weren't installing the device headers when compiling
without XINPUT support. But we would include them from gdkx.h, so
essentially the build was broken.
With this patch the types will exist but not do anything.
This function allocates the button mask, so free it after
use, or right before the next XIQueryPointer() call, as done
in gdk_x11_device_xi2_window_at_position().
mods_state->effective is not being set in XIQueryPointer() currently, so
use base|latched|locked instead, effective is nothing else than a shorthand
for these ORs, and these 3 values are set correctly anytime.
Moving the direct-access redefinitions of various macros
to gdkprivate-x11.h and use that header throughout in x11/.
Also remove a workaround for a long-fixed X server bug.
Use the grab and ungrab vfuncs from the frontend instead of the
_gdk_windowing wrappers, and move some things around accordingly.
Again, only the X11 backend has been updated, other backends
need to be updated to match.
