input/tablet: add seatop_down entry for tablet input

Currently, when tablet input exits a window during an implicit grab, it
passes focus to another window.

For instance, this is problematic when trying to drag a scrollbar, and
exiting the window — the scrollbar motion stops. Additionally,
without `focus_follows_mouse no`, the tablet passes focus to whatever
surface it goes over regardless of if there is an active implicit.

If the tablet is over a surface that does not bind tablet handlers, sway
will fall back to pointer emulation, and all of this works fine. It
probably should have consistent behavior between emulated and
not-emulated input, though.

This commit adds a condition for entering seatop_down when a tablet's
tool tip goes down, and exiting when it goes up. Since events won't be
routed through seatop_default, this prevents windows losing focus during
implicit grabs.

Closes #5302.

1 files changed, 6 insertions, 0 deletions

diff --git a/include/sway/input/seat.h b/include/sway/input/seat.h
index 66f8f7e4..e313a206 100644
--- a/include/sway/input/seat.h
+++ b/include/sway/input/seat.h
@@ -23,6 +23,8 @@ struct sway_seatop_impl {
         void (*rebase)(struct sway_seat *seat, uint32_t time_msec);
         void (*tablet_tool_motion)(struct sway_seat *seat,
                         struct sway_tablet_tool *tool, uint32_t time_msec, double dx, double dy);
+        void (*tablet_tool_tip)(struct sway_seat *seat, struct sway_tablet_tool *tool,
+                        uint32_t time_msec, enum wlr_tablet_tool_tip_state state);
         void (*end)(struct sway_seat *seat);
         void (*unref)(struct sway_seat *seat, struct sway_container *con);
         void (*render)(struct sway_seat *seat, struct sway_output *output,
@@ -269,6 +271,10 @@ void seatop_pointer_motion(struct sway_seat *seat, uint32_t time_msec,
 void seatop_pointer_axis(struct sway_seat *seat,
                 struct wlr_event_pointer_axis *event);
 
+void seatop_tablet_tool_tip(struct sway_seat *seat,
+                struct sway_tablet_tool *tool, uint32_t time_msec,
+                enum wlr_tablet_tool_tip_state state);
+
 void seatop_tablet_tool_motion(struct sway_seat *seat,
                 struct sway_tablet_tool *tool, uint32_t time_msec, double dx, double dy);