From 8162d6659af506ac4d65e090667c30c0617ca17e Mon Sep 17 00:00:00 2001
From: Frank Praznik <[EMAIL REDACTED]>
Date: Fri, 7 Apr 2023 17:27:50 -0400
Subject: [PATCH] wayland: Use the integer buffer scale event when applicable
wl_compositor v6 introduces the preferred buffer scale event, which serves a similar function to the fractional scale protocol, but deals in integer scale factors. Listen to this event when the wl_compositor version is >= 6 and the fractional scale protocol is not present to set the scale factor for surfaces.
---
src/video/wayland/SDL_waylandvideo.c | 8 +-
src/video/wayland/SDL_waylandwindow.c | 101 +++++++++++++++-----------
2 files changed, 66 insertions(+), 43 deletions(-)
diff --git a/src/video/wayland/SDL_waylandvideo.c b/src/video/wayland/SDL_waylandvideo.c
index c919e8314ed2..de63c6bcb8ba 100644
--- a/src/video/wayland/SDL_waylandvideo.c
+++ b/src/video/wayland/SDL_waylandvideo.c
@@ -62,6 +62,12 @@
#define WAYLANDVID_DRIVER_NAME "wayland"
+#if SDL_WAYLAND_CHECK_VERSION(1, 22, 0)
+#define SDL_WL_COMPOSITOR_VERSION 6
+#else
+#define SDL_WL_COMPOSITOR_VERSION 4
+#endif
+
#if SDL_WAYLAND_CHECK_VERSION(1, 20, 0)
#define SDL_WL_OUTPUT_VERSION 4
#else
@@ -792,7 +798,7 @@ static void display_handle_global(void *data, struct wl_registry *registry, uint
/*printf("WAYLAND INTERFACE: %s\n", interface);*/
if (SDL_strcmp(interface, "wl_compositor") == 0) {
- d->compositor = wl_registry_bind(d->registry, id, &wl_compositor_interface, SDL_min(4, version));
+ d->compositor = wl_registry_bind(d->registry, id, &wl_compositor_interface, SDL_min(SDL_WL_COMPOSITOR_VERSION, version));
} else if (SDL_strcmp(interface, "wl_output") == 0) {
Wayland_add_display(d, id, SDL_min(version, SDL_WL_OUTPUT_VERSION));
} else if (SDL_strcmp(interface, "wl_seat") == 0) {
diff --git a/src/video/wayland/SDL_waylandwindow.c b/src/video/wayland/SDL_waylandwindow.c
index 0e7da693a6bc..aadbf1760e9f 100644
--- a/src/video/wayland/SDL_waylandwindow.c
+++ b/src/video/wayland/SDL_waylandwindow.c
@@ -968,33 +968,48 @@ static const struct qt_extended_surface_listener extended_surface_listener = {
};
#endif /* SDL_VIDEO_DRIVER_WAYLAND_QT_TOUCH */
-static void update_scale_factor(SDL_WindowData *window)
+static void Wayland_HandlePreferredScaleChanged(SDL_WindowData *window_data, float factor)
{
- float old_factor = window->windowed_scale_factor;
- float new_factor;
- int i;
+ const float old_factor = window_data->windowed_scale_factor;
- if (!(window->sdlwindow->flags & SDL_WINDOW_ALLOW_HIGHDPI)) {
+ if (!(window_data->sdlwindow->flags & SDL_WINDOW_ALLOW_HIGHDPI)) {
/* Scale will always be 1, just ignore this */
return;
}
+ if (!FloatEqual(factor, old_factor)) {
+ window_data->windowed_scale_factor = factor;
+ ConfigureWindowGeometry(window_data->sdlwindow);
+ }
+}
+
+static void Wayland_MaybeUpdateScaleFactor(SDL_WindowData *window)
+{
+ float factor;
+ int i;
+
+ /* If the fractional scale protocol is present or the core protocol supports the
+ * preferred buffer scale event, the compositor will tell explicitly the application
+ * what scale it wants via these events, so don't try to determine the scale factor
+ * from which displays the surface has entered.
+ */
+ if (window->fractional_scale || wl_surface_get_version(window->surface) >= WL_SURFACE_PREFERRED_BUFFER_SCALE_SINCE_VERSION) {
+ return;
+ }
+
if (window->num_outputs != 0) {
/* Check every display's factor, use the highest */
- new_factor = 0.0f;
+ factor = 0.0f;
for (i = 0; i < window->num_outputs; i++) {
SDL_DisplayData *driverdata = window->outputs[i];
- new_factor = SDL_max(new_factor, driverdata->scale_factor);
+ factor = SDL_max(factor, driverdata->scale_factor);
}
} else {
/* No monitor (somehow)? Just fall back. */
- new_factor = old_factor;
+ factor = window->windowed_scale_factor;
}
- if (!FloatEqual(new_factor, old_factor)) {
- window->windowed_scale_factor = new_factor;
- ConfigureWindowGeometry(window->sdlwindow);
- }
+ Wayland_HandlePreferredScaleChanged(window, factor);
}
/* While we can't get window position from the compositor, we do at least know
@@ -1060,10 +1075,7 @@ static void handle_surface_enter(void *data, struct wl_surface *surface,
/* Update the scale factor after the move so that fullscreen outputs are updated. */
Wayland_move_window(window->sdlwindow, driverdata);
-
- if (!window->fractional_scale) {
- update_scale_factor(window);
- }
+ Wayland_MaybeUpdateScaleFactor(window);
}
static void handle_surface_leave(void *data, struct wl_surface *surface,
@@ -1100,14 +1112,42 @@ static void handle_surface_leave(void *data, struct wl_surface *surface,
window->outputs[window->num_outputs - 1]);
}
- if (!window->fractional_scale) {
- update_scale_factor(window);
+ Wayland_MaybeUpdateScaleFactor(window);
+}
+
+static void handle_preferred_buffer_scale(void *data, struct wl_surface *wl_surface, int32_t factor)
+{
+ SDL_WindowData *wind = data;
+
+ /* The spec is unclear on how this interacts with the fractional scaling protocol,
+ * so, for now, assume that the fractional scaling protocol takes priority and
+ * only listen to this event if the fractional scaling protocol is not present.
+ */
+ if (!wind->fractional_scale) {
+ Wayland_HandlePreferredScaleChanged(data, (float)factor);
}
}
+static void handle_preferred_buffer_transform(void *data, struct wl_surface *wl_surface, uint32_t transform)
+{
+ /* Nothing to do here. */
+}
+
static const struct wl_surface_listener surface_listener = {
handle_surface_enter,
- handle_surface_leave
+ handle_surface_leave,
+ handle_preferred_buffer_scale,
+ handle_preferred_buffer_transform
+};
+
+static void handle_preferred_fractional_scale(void *data, struct wp_fractional_scale_v1 *wp_fractional_scale_v1, uint32_t scale)
+{
+ const float factor = scale / 120.; /* 120 is a magic number defined in the spec as a common denominator */
+ Wayland_HandlePreferredScaleChanged(data, factor);
+}
+
+static const struct wp_fractional_scale_v1_listener fractional_scale_listener = {
+ handle_preferred_fractional_scale
};
static void SetKeyboardFocus(SDL_Window *window)
@@ -1605,29 +1645,6 @@ int Wayland_FlashWindow(_THIS, SDL_Window *window, SDL_FlashOperation operation)
return 0;
}
-static void handle_preferred_scale_changed(void *data,
- struct wp_fractional_scale_v1 *wp_fractional_scale_v1,
- uint preferred_scale)
-{
- SDL_WindowData *window = data;
- float old_factor = window->windowed_scale_factor;
- float new_factor = preferred_scale / 120.; /* 120 is a magic number defined in the spec as a common denominator*/
-
- if (!(window->sdlwindow->flags & SDL_WINDOW_ALLOW_HIGHDPI)) {
- /* Scale will always be 1, just ignore this */
- return;
- }
-
- if (!FloatEqual(new_factor, old_factor)) {
- window->windowed_scale_factor = new_factor;
- ConfigureWindowGeometry(window->sdlwindow);
- }
-}
-
-static const struct wp_fractional_scale_v1_listener fractional_scale_listener = {
- handle_preferred_scale_changed
-};
-
#ifdef SDL_VIDEO_DRIVER_WAYLAND_QT_TOUCH
static void SDLCALL QtExtendedSurface_OnHintChanged(void *userdata, const char *name,
const char *oldValue, const char *newValue)