The events are routed through a new slave device with type GDK_SOURCE_TOUCHSCREEN, minimal tracking of touches is done to keep the state for each of those.
https://bugzilla.gnome.org/show_bug.cgi?id=728426
1a2a5a4 wayland: handle the wl_touch interface
gdk/wayland/gdkdevice-wayland.c | 232 ++++++++++++++++++++++++++++++++++++++-
1 file changed, 231 insertions(+), 1 deletion(-)
Upstream: git.gnome.org