From d102022c95ac60e13ff4f00060561bf6b74c170d Mon Sep 17 00:00:00 2001
From: Frank Praznik <[EMAIL REDACTED]>
Date: Mon, 5 Jan 2026 13:43:35 -0500
Subject: [PATCH] wayland: Handle all mouse state in a frame
The hybrid handling can still result in cases where a final event is dropped when the pointer leaves a surface. The spec says that all pointer events should be handled within a frame, so, do so.
---
src/video/wayland/SDL_waylandevents.c | 205 +++++++++++++++---------
src/video/wayland/SDL_waylandevents_c.h | 7 +-
2 files changed, 132 insertions(+), 80 deletions(-)
diff --git a/src/video/wayland/SDL_waylandevents.c b/src/video/wayland/SDL_waylandevents.c
index 3c42c02f544c8..ece3e4c18f27f 100644
--- a/src/video/wayland/SDL_waylandevents.c
+++ b/src/video/wayland/SDL_waylandevents.c
@@ -780,25 +780,35 @@ static void pointer_handle_motion(void *data, struct wl_pointer *pointer,
uint32_t time, wl_fixed_t sx, wl_fixed_t sy)
{
SDL_WaylandSeat *seat = (SDL_WaylandSeat *)data;
+ const Uint64 timestamp = Wayland_GetPointerTimestamp(seat, time);
- seat->pointer.pending_frame.have_absolute = true;
seat->pointer.pending_frame.absolute.sx = sx;
seat->pointer.pending_frame.absolute.sy = sy;
- /* The relative pointer timestamp is higher resolution than the default millisecond timestamp,
- * but lower than the highres timestamp. Use the best timer available for this frame, but still
- * process the pending millisecond timestamp to update the offset value for other events.
- */
- const Uint64 timestamp = Wayland_GetPointerTimestamp(seat, time);
- if (!seat->pointer.pending_frame.have_relative || seat->pointer.timestamps) {
- seat->pointer.pending_frame.timestamp_ns = timestamp;
- }
+ if (wl_pointer_get_version(seat->pointer.wl_pointer) >= WL_POINTER_FRAME_SINCE_VERSION) {
+ seat->pointer.pending_frame.have_absolute = true;
- if (wl_pointer_get_version(seat->pointer.wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION) {
+ /* The relative pointer timestamp is higher resolution than the default millisecond timestamp,
+ * but lower than the highres timestamp. Use the best timer available for this frame,
+ */
+ if (!seat->pointer.pending_frame.have_relative || seat->pointer.timestamps) {
+ seat->pointer.pending_frame.timestamp_ns = timestamp;
+ }
+ } else {
+ seat->pointer.pending_frame.timestamp_ns = timestamp;
pointer_dispatch_absolute_motion(seat);
}
}
+static void pointer_dispatch_enter(SDL_WaylandSeat *seat)
+{
+ SDL_WindowData *window = seat->pointer.pending_frame.enter_window;
+
+ seat->pointer.focus = window;
+ ++window->pointer_focus_count;
+ SDL_SetMouseFocus(window->sdlwindow);
+}
+
static void pointer_handle_enter(void *data, struct wl_pointer *pointer,
uint32_t serial, struct wl_surface *surface,
wl_fixed_t sx_w, wl_fixed_t sy_w)
@@ -815,30 +825,21 @@ static void pointer_handle_enter(void *data, struct wl_pointer *pointer,
}
SDL_WaylandSeat *seat = (SDL_WaylandSeat *)data;
- seat->pointer.focus = window;
+ seat->pointer.pending_frame.enter_window = window;
seat->pointer.enter_serial = serial;
- ++window->pointer_focus_count;
- SDL_SetMouseFocus(window->sdlwindow);
/* In the case of e.g. a pointer confine warp, we may receive an enter
* event with no following motion event, but with the new coordinates
* as part of the enter event.
- *
- * If another event with a real timestamp is part of this frame, use it.
- * Otherwise, set it to 0 to use the current system timer.
*/
- if (!seat->pointer.pending_frame.have_absolute &&
- !seat->pointer.pending_frame.have_relative &&
- !seat->pointer.pending_frame.have_axis) {
- seat->pointer.pending_frame.timestamp_ns = 0;
- }
seat->pointer.pending_frame.absolute.sx = sx_w;
seat->pointer.pending_frame.absolute.sy = sy_w;
- seat->pointer.pending_frame.have_absolute = true;
- seat->pointer.pending_frame.have_enter = true;
-
- if (wl_pointer_get_version(seat->pointer.wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION) {
+ if (wl_pointer_get_version(seat->pointer.wl_pointer) >= WL_POINTER_FRAME_SINCE_VERSION) {
+ seat->pointer.pending_frame.have_absolute = true;
+ } else {
+ seat->pointer.pending_frame.timestamp_ns = 0;
+ pointer_dispatch_enter(seat);
pointer_dispatch_absolute_motion(seat);
// Update the pointer grab state.
@@ -856,6 +857,33 @@ static void pointer_handle_enter(void *data, struct wl_pointer *pointer,
}
}
+static void pointer_dispatch_leave(SDL_WaylandSeat *seat)
+{
+ SDL_WindowData *window = seat->pointer.pending_frame.leave_window;
+
+ if (window) {
+ // Clear the capture flag and raise all buttons
+ window->sdlwindow->flags &= ~SDL_WINDOW_MOUSE_CAPTURE;
+
+ seat->pointer.focus = NULL;
+ for (Uint8 i = 1; seat->pointer.buttons_pressed; ++i) {
+ if (seat->pointer.buttons_pressed & SDL_BUTTON_MASK(i)) {
+ SDL_SendMouseButton(0, window->sdlwindow, seat->pointer.sdl_id, i, false);
+ seat->pointer.buttons_pressed &= ~SDL_BUTTON_MASK(i);
+ }
+ }
+
+ /* A pointer leave event may be emitted if the compositor hides the pointer in response to receiving a touch event.
+ * Don't relinquish focus if the surface has active touches, as the compositor is just transitioning from mouse to touch mode.
+ */
+ SDL_Window *mouse_focus = SDL_GetMouseFocus();
+ const bool had_focus = mouse_focus && window->sdlwindow == mouse_focus;
+ if (!--window->pointer_focus_count && had_focus && !window->active_touch_count) {
+ SDL_SetMouseFocus(NULL);
+ }
+ }
+}
+
static void pointer_handle_leave(void *data, struct wl_pointer *pointer,
uint32_t serial, struct wl_surface *surface)
{
@@ -870,29 +898,13 @@ static void pointer_handle_leave(void *data, struct wl_pointer *pointer,
return;
}
- // Clear the capture flag and raise all buttons
- window->sdlwindow->flags &= ~SDL_WINDOW_MOUSE_CAPTURE;
-
SDL_WaylandSeat *seat = (SDL_WaylandSeat *)data;
- seat->pointer.focus = NULL;
- for (int i = 1; seat->pointer.buttons_pressed; ++i) {
- if (seat->pointer.buttons_pressed & SDL_BUTTON_MASK(i)) {
- SDL_SendMouseButton(0, window->sdlwindow, seat->pointer.sdl_id, i, false);
- seat->pointer.buttons_pressed &= ~SDL_BUTTON_MASK(i);
- }
- }
-
- /* A pointer leave event may be emitted if the compositor hides the pointer in response to receiving a touch event.
- * Don't relinquish focus if the surface has active touches, as the compositor is just transitioning from mouse to touch mode.
- */
- SDL_Window *mouse_focus = SDL_GetMouseFocus();
- const bool had_focus = mouse_focus && window->sdlwindow == mouse_focus;
- if (!--window->pointer_focus_count && had_focus && !window->active_touch_count) {
- SDL_SetMouseFocus(NULL);
+ seat->pointer.pending_frame.leave_window = window;
+ if (wl_pointer_get_version(seat->pointer.wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION && window == seat->pointer.focus) {
+ pointer_dispatch_leave(seat);
+ Wayland_SeatUpdatePointerGrab(seat);
+ Wayland_SeatUpdatePointerCursor(seat);
}
-
- Wayland_SeatUpdatePointerGrab(seat);
- Wayland_SeatUpdatePointerCursor(seat);
}
static bool Wayland_ProcessHitTest(SDL_WaylandSeat *seat, Uint32 serial)
@@ -978,47 +990,26 @@ static bool Wayland_ProcessHitTest(SDL_WaylandSeat *seat, Uint32 serial)
return false;
}
-static void pointer_handle_button_common(SDL_WaylandSeat *seat, uint32_t serial,
- Uint64 nsTimestamp, uint32_t button, uint32_t state_w)
+static void pointer_dispatch_button(SDL_WaylandSeat *seat, Uint8 sdl_button, bool down)
{
SDL_WindowData *window = seat->pointer.focus;
- enum wl_pointer_button_state state = state_w;
- Uint8 sdl_button;
- const bool down = (state != 0);
-
- switch (button) {
- case BTN_LEFT:
- sdl_button = SDL_BUTTON_LEFT;
- break;
- case BTN_MIDDLE:
- sdl_button = SDL_BUTTON_MIDDLE;
- break;
- case BTN_RIGHT:
- sdl_button = SDL_BUTTON_RIGHT;
- break;
- default:
- sdl_button = SDL_BUTTON_X1 + (button - BTN_SIDE);
- break;
- }
if (window) {
bool ignore_click = false;
- if (state) {
- Wayland_UpdateImplicitGrabSerial(seat, serial);
+ if (down) {
seat->pointer.buttons_pressed |= SDL_BUTTON_MASK(sdl_button);
} else {
- seat->pointer.buttons_pressed &= ~(SDL_BUTTON_MASK(sdl_button));
+ seat->pointer.buttons_pressed &= ~SDL_BUTTON_MASK(sdl_button);
}
- if (sdl_button == SDL_BUTTON_LEFT && Wayland_ProcessHitTest(seat, serial)) {
+ if (sdl_button == SDL_BUTTON_LEFT && Wayland_ProcessHitTest(seat, seat->last_implicit_grab_serial)) {
return; // don't pass this event on to app.
}
// Possibly ignore this click if it was to gain focus.
if (window->last_focus_event_time_ns) {
- if (state == WL_POINTER_BUTTON_STATE_PRESSED &&
- (SDL_GetTicksNS() - window->last_focus_event_time_ns) < WAYLAND_FOCUS_CLICK_TIMEOUT_NS) {
+ if (down && (SDL_GetTicksNS() - window->last_focus_event_time_ns) < WAYLAND_FOCUS_CLICK_TIMEOUT_NS) {
ignore_click = !SDL_GetHintBoolean(SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, false);
}
@@ -1041,7 +1032,7 @@ static void pointer_handle_button_common(SDL_WaylandSeat *seat, uint32_t serial,
}
if (!ignore_click) {
- SDL_SendMouseButton(nsTimestamp, window->sdlwindow, seat->pointer.sdl_id, sdl_button, down);
+ SDL_SendMouseButton(seat->pointer.pending_frame.timestamp_ns, window->sdlwindow, seat->pointer.sdl_id, sdl_button, down);
}
}
}
@@ -1050,7 +1041,38 @@ static void pointer_handle_button(void *data, struct wl_pointer *pointer, uint32
uint32_t time, uint32_t button, uint32_t state_w)
{
SDL_WaylandSeat *seat = data;
- pointer_handle_button_common(seat, serial, Wayland_GetPointerTimestamp(seat, time), button, state_w);
+ Uint8 sdl_button;
+
+ switch (button) {
+ case BTN_LEFT:
+ sdl_button = SDL_BUTTON_LEFT;
+ break;
+ case BTN_MIDDLE:
+ sdl_button = SDL_BUTTON_MIDDLE;
+ break;
+ case BTN_RIGHT:
+ sdl_button = SDL_BUTTON_RIGHT;
+ break;
+ default:
+ sdl_button = SDL_BUTTON_X1 + (button - BTN_SIDE);
+ break;
+ }
+
+ if (state_w) {
+ Wayland_UpdateImplicitGrabSerial(seat, serial);
+ }
+
+ seat->pointer.pending_frame.timestamp_ns = Wayland_GetPointerTimestamp(seat, time);;
+
+ if (wl_seat_get_version(seat->wl_seat) >= WL_POINTER_FRAME_SINCE_VERSION) {
+ if (state_w) {
+ seat->pointer.pending_frame.buttons_pressed |= SDL_BUTTON_MASK(sdl_button);
+ } else {
+ seat->pointer.pending_frame.buttons_released |= SDL_BUTTON_MASK(sdl_button);
+ }
+ } else {
+ pointer_dispatch_button(seat, sdl_button, state_w != 0);
+ }
}
static void pointer_handle_axis_common_v1(SDL_WaylandSeat *seat,
@@ -1251,10 +1273,18 @@ static void pointer_handle_frame(void *data, struct wl_pointer *pointer)
{
SDL_WaylandSeat *seat = data;
+ if (seat->pointer.pending_frame.enter_window) {
+ if (seat->pointer.pending_frame.leave_window == seat->pointer.focus) {
+ // Leaving the previous surface before entering a new surface.
+ pointer_dispatch_leave(seat);
+ }
+ pointer_dispatch_enter(seat);
+ }
+
if (seat->pointer.pending_frame.have_absolute) {
pointer_dispatch_absolute_motion(seat);
- if (seat->pointer.pending_frame.have_enter) {
+ if (seat->pointer.pending_frame.enter_window) {
// Update the pointer grab state.
Wayland_SeatUpdatePointerGrab(seat);
@@ -1274,10 +1304,28 @@ static void pointer_handle_frame(void *data, struct wl_pointer *pointer)
pointer_dispatch_relative_motion(seat);
}
+ for (Uint8 i = 1; seat->pointer.pending_frame.buttons_pressed || seat->pointer.pending_frame.buttons_released; ++i) {
+ const Uint32 mask = SDL_BUTTON_MASK(i);
+ if (seat->pointer.pending_frame.buttons_pressed & mask) {
+ pointer_dispatch_button(seat, i, true);
+ seat->pointer.pending_frame.buttons_pressed &= ~mask;
+ }
+ if (seat->pointer.pending_frame.buttons_released & mask) {
+ pointer_dispatch_button(seat, i, false);
+ seat->pointer.pending_frame.buttons_released &= ~mask;
+ }
+ }
+
if (seat->pointer.pending_frame.have_axis) {
pointer_dispatch_axis(seat);
}
+ if (seat->pointer.pending_frame.leave_window == seat->pointer.focus) {
+ pointer_dispatch_leave(seat);
+ Wayland_SeatUpdatePointerGrab(seat);
+ Wayland_SeatUpdatePointerCursor(seat);
+ }
+
SDL_zero(seat->pointer.pending_frame);
}
@@ -1297,7 +1345,6 @@ static void pointer_handle_axis_discrete(void *data, struct wl_pointer *pointer,
uint32_t axis, int32_t discrete)
{
SDL_WaylandSeat *seat = data;
-
pointer_handle_axis_common(seat, SDL_WAYLAND_AXIS_EVENT_DISCRETE, axis, wl_fixed_from_int(discrete));
}
@@ -1305,7 +1352,6 @@ static void pointer_handle_axis_value120(void *data, struct wl_pointer *pointer,
uint32_t axis, int32_t value120)
{
SDL_WaylandSeat *seat = data;
-
pointer_handle_axis_common(seat, SDL_WAYLAND_AXIS_EVENT_VALUE120, axis, wl_fixed_from_int(value120));
}
@@ -1335,14 +1381,15 @@ static void relative_pointer_handle_relative_motion(void *data,
SDL_WaylandSeat *seat = data;
// Relative pointer event times are in microsecond granularity.
- seat->pointer.pending_frame.have_relative = true;
seat->pointer.pending_frame.relative.dx = dx;
seat->pointer.pending_frame.relative.dy = dy;
seat->pointer.pending_frame.relative.dx_unaccel = dx_unaccel;
seat->pointer.pending_frame.relative.dy_unaccel = dy_unaccel;
seat->pointer.pending_frame.timestamp_ns = Wayland_AdjustEventTimestampBase(SDL_US_TO_NS(((Uint64)time_hi << 32) | (Uint64)time_lo));
- if (wl_pointer_get_version(seat->pointer.wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION) {
+ if (wl_pointer_get_version(seat->pointer.wl_pointer) >= WL_POINTER_FRAME_SINCE_VERSION) {
+ seat->pointer.pending_frame.have_relative = true;
+ } else {
pointer_dispatch_relative_motion(seat);
}
}
diff --git a/src/video/wayland/SDL_waylandevents_c.h b/src/video/wayland/SDL_waylandevents_c.h
index 6b0bca47df78c..4ca60a43e961d 100644
--- a/src/video/wayland/SDL_waylandevents_c.h
+++ b/src/video/wayland/SDL_waylandevents_c.h
@@ -205,7 +205,9 @@ typedef struct SDL_WaylandSeat
bool have_absolute;
bool have_relative;
bool have_axis;
- bool have_enter;
+
+ Uint32 buttons_pressed;
+ Uint32 buttons_released;
struct
{
@@ -232,6 +234,9 @@ typedef struct SDL_WaylandSeat
SDL_MouseWheelDirection direction;
} axis;
+ SDL_WindowData *enter_window;
+ SDL_WindowData *leave_window;
+
// Event timestamp in nanoseconds
Uint64 timestamp_ns;
} pending_frame;