File tearing.patch of Package SDL3
diff --git a/include/SDL3/SDL_hints.h b/include/SDL3/SDL_hints.h
index 7961157cc..e94513fec 100644
--- a/include/SDL3/SDL_hints.h
+++ b/include/SDL3/SDL_hints.h
@@ -3574,6 +3574,25 @@ extern "C" {
*/
#define SDL_HINT_VIDEO_WAYLAND_ALLOW_LIBDECOR "SDL_VIDEO_WAYLAND_ALLOW_LIBDECOR"
+/**
+ * A variable controlling whether tearing is allowed for low-latency on Wayland.
+ *
+ * Wayland compositors may disregard this variable in some conditions, or may not
+ * support tearing entirely.
+ * Read their documentation about tearing to properly use this variable.
+ *
+ * The variable can be set to the following values:
+ *
+ * - "0": Tearing is disabled initially, but may get enabled on some conditions,
+ * like user preferences. (default)
+ * - "1": Tearing is allowed, if available.
+ *
+ * This hint should be set before creating a window.
+ *
+ * \since This hint is available since SDL 3.0.0.
+ */
+#define SDL_HINT_VIDEO_WAYLAND_ALLOW_TEARING "SDL_VIDEO_WAYLAND_ALLOW_TEARING"
+
/**
* A variable controlling whether video mode emulation is enabled under
* Wayland.
diff --git a/src/video/wayland/SDL_waylandvideo.c b/src/video/wayland/SDL_waylandvideo.c
index a1b527664..254c8a05e 100644
--- a/src/video/wayland/SDL_waylandvideo.c
+++ b/src/video/wayland/SDL_waylandvideo.c
@@ -56,6 +56,7 @@
#include "primary-selection-unstable-v1-client-protocol.h"
#include "relative-pointer-unstable-v1-client-protocol.h"
#include "tablet-v2-client-protocol.h"
+#include "tearing-control-v1-client-protocol.h"
#include "text-input-unstable-v3-client-protocol.h"
#include "viewporter-client-protocol.h"
#include "xdg-activation-v1-client-protocol.h"
@@ -1299,6 +1300,8 @@ static void display_handle_global(void *data, struct wl_registry *registry, uint
} else if (SDL_strcmp(interface, "wp_cursor_shape_manager_v1") == 0) {
d->cursor_shape_manager = wl_registry_bind(d->registry, id, &wp_cursor_shape_manager_v1_interface, 1);
Wayland_DisplayInitCursorShapeManager(d);
+ } else if (SDL_strcmp(interface, "wp_tearing_control_manager_v1") == 0) {
+ d->wp_tearing_control_manager_v1 = wl_registry_bind(d->registry, id, &wp_tearing_control_manager_v1_interface, 1);
} else if (SDL_strcmp(interface, "zxdg_exporter_v2") == 0) {
d->zxdg_exporter_v2 = wl_registry_bind(d->registry, id, &zxdg_exporter_v2_interface, 1);
} else if (SDL_strcmp(interface, "xdg_wm_dialog_v1") == 0) {
@@ -1628,6 +1631,11 @@ static void Wayland_VideoCleanup(SDL_VideoDevice *_this)
data->wp_pointer_warp_v1 = NULL;
}
+ if (data->wp_tearing_control_manager_v1) {
+ wp_tearing_control_manager_v1_destroy(data->wp_tearing_control_manager_v1);
+ data->wp_tearing_control_manager_v1 = NULL;
+ }
+
if (data->compositor) {
wl_compositor_destroy(data->compositor);
data->compositor = NULL;
diff --git a/src/video/wayland/SDL_waylandvideo.h b/src/video/wayland/SDL_waylandvideo.h
index e96473113..b83dd6eaa 100644
--- a/src/video/wayland/SDL_waylandvideo.h
+++ b/src/video/wayland/SDL_waylandvideo.h
@@ -66,6 +66,7 @@ struct SDL_VideoData
struct zwp_relative_pointer_manager_v1 *relative_pointer_manager;
struct zwp_pointer_constraints_v1 *pointer_constraints;
struct wp_pointer_warp_v1 *wp_pointer_warp_v1;
+ struct wp_tearing_control_manager_v1 *wp_tearing_control_manager_v1;
struct wp_cursor_shape_manager_v1 *cursor_shape_manager;
struct wl_data_device_manager *data_device_manager;
struct zwp_primary_selection_device_manager_v1 *primary_selection_device_manager;
diff --git a/src/video/wayland/SDL_waylandwindow.c b/src/video/wayland/SDL_waylandwindow.c
index eafe9f8b8..f4af0ad93 100644
--- a/src/video/wayland/SDL_waylandwindow.c
+++ b/src/video/wayland/SDL_waylandwindow.c
@@ -35,6 +35,7 @@
#include "../../SDL_hints_c.h"
#include "SDL_waylandcolor.h"
+#include "tearing-control-v1-client-protocol.h"
#include "alpha-modifier-v1-client-protocol.h"
#include "xdg-shell-client-protocol.h"
#include "xdg-decoration-unstable-v1-client-protocol.h"
@@ -2650,6 +2651,11 @@ bool Wayland_CreateWindow(SDL_VideoDevice *_this, SDL_Window *window, SDL_Proper
}
}
+ if (SDL_GetHintBoolean(SDL_HINT_VIDEO_WAYLAND_ALLOW_TEARING, false) && c->wp_tearing_control_manager_v1) {
+ data->wp_tearing_control_v1 = wp_tearing_control_manager_v1_get_tearing_control(c->wp_tearing_control_manager_v1, data->surface);
+ wp_tearing_control_v1_set_presentation_hint(data->wp_tearing_control_v1, WP_TEARING_CONTROL_V1_PRESENTATION_HINT_ASYNC);
+ }
+
// Must be called before EGL configuration to set the drawable backbuffer size.
ConfigureWindowGeometry(window);
@@ -3137,6 +3143,10 @@ void Wayland_DestroyWindow(SDL_VideoDevice *_this, SDL_Window *window)
wp_color_management_surface_feedback_v1_destroy(wind->wp_color_management_surface_feedback);
}
+ if (wind->wp_tearing_control_v1) {
+ wp_tearing_control_v1_destroy(wind->wp_tearing_control_v1);
+ }
+
SDL_free(wind->outputs);
SDL_free(wind->app_id);
diff --git a/src/video/wayland/SDL_waylandwindow.h b/src/video/wayland/SDL_waylandwindow.h
index 7099462ab..917688688 100644
--- a/src/video/wayland/SDL_waylandwindow.h
+++ b/src/video/wayland/SDL_waylandwindow.h
@@ -107,6 +107,7 @@ struct SDL_WindowData
#ifdef SDL_VIDEO_OPENGL_EGL
EGLSurface egl_surface;
#endif
+ struct wp_tearing_control_v1 *wp_tearing_control_v1;
struct zxdg_toplevel_decoration_v1 *server_decoration;
struct zwp_idle_inhibitor_v1 *idle_inhibitor;
struct xdg_activation_token_v1 *activation_token;
diff --git a/wayland-protocols/tearing-control-v1.xml b/wayland-protocols/tearing-control-v1.xml
new file mode 100644
index 000000000..9c44fbfca
--- /dev/null
+++ b/wayland-protocols/tearing-control-v1.xml
@@ -0,0 +1,123 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="tearing_control_v1">
+ <copyright>
+ Copyright © 2021 Xaver Hugl
+
+ Permission is hereby granted, free of charge, to any person obtaining a
+ copy of this software and associated documentation files (the "Software"),
+ to deal in the Software without restriction, including without limitation
+ the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ and/or sell copies of the Software, and to permit persons to whom the
+ Software is furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice (including the next
+ paragraph) shall be included in all copies or substantial portions of the
+ Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ DEALINGS IN THE SOFTWARE.
+ </copyright>
+
+ <interface name="wp_tearing_control_manager_v1" version="1">
+ <description summary="protocol for tearing control">
+ For some use cases like games or drawing tablets it can make sense to
+ reduce latency by accepting tearing with the use of asynchronous page
+ flips. This global is a factory interface, allowing clients to inform
+ which type of presentation the content of their surfaces is suitable for.
+
+ Graphics APIs like EGL or Vulkan, that manage the buffer queue and commits
+ of a wl_surface themselves, are likely to be using this extension
+ internally. If a client is using such an API for a wl_surface, it should
+ not directly use this extension on that surface, to avoid raising a
+ tearing_control_exists protocol error.
+
+ Warning! The protocol described in this file is currently in the testing
+ phase. Backward compatible changes may be added together with the
+ corresponding interface version bump. Backward incompatible changes can
+ only be done by creating a new major version of the extension.
+ </description>
+
+ <request name="destroy" type="destructor">
+ <description summary="destroy tearing control factory object">
+ Destroy this tearing control factory object. Other objects, including
+ wp_tearing_control_v1 objects created by this factory, are not affected
+ by this request.
+ </description>
+ </request>
+
+ <enum name="error">
+ <entry name="tearing_control_exists" value="0"
+ summary="the surface already has a tearing object associated"/>
+ </enum>
+
+ <request name="get_tearing_control">
+ <description summary="extend surface interface for tearing control">
+ Instantiate an interface extension for the given wl_surface to request
+ asynchronous page flips for presentation.
+
+ If the given wl_surface already has a wp_tearing_control_v1 object
+ associated, the tearing_control_exists protocol error is raised.
+ </description>
+ <arg name="id" type="new_id" interface="wp_tearing_control_v1"/>
+ <arg name="surface" type="object" interface="wl_surface"/>
+ </request>
+ </interface>
+
+ <interface name="wp_tearing_control_v1" version="1">
+ <description summary="per-surface tearing control interface">
+ An additional interface to a wl_surface object, which allows the client
+ to hint to the compositor if the content on the surface is suitable for
+ presentation with tearing.
+ The default presentation hint is vsync. See presentation_hint for more
+ details.
+
+ If the associated wl_surface is destroyed, this object becomes inert and
+ should be destroyed.
+ </description>
+
+ <enum name="presentation_hint">
+ <description summary="presentation hint values">
+ This enum provides information for if submitted frames from the client
+ may be presented with tearing.
+ </description>
+ <entry name="vsync" value="0">
+ <description summary="tearing-free presentation">
+ The content of this surface is meant to be synchronized to the
+ vertical blanking period. This should not result in visible tearing
+ and may result in a delay before a surface commit is presented.
+ </description>
+ </entry>
+ <entry name="async" value="1">
+ <description summary="asynchronous presentation">
+ The content of this surface is meant to be presented with minimal
+ latency and tearing is acceptable.
+ </description>
+ </entry>
+ </enum>
+
+ <request name="set_presentation_hint">
+ <description summary="set presentation hint">
+ Set the presentation hint for the associated wl_surface. This state is
+ double-buffered, see wl_surface.commit.
+
+ The compositor is free to dynamically respect or ignore this hint based
+ on various conditions like hardware capabilities, surface state and
+ user preferences.
+ </description>
+ <arg name="hint" type="uint" enum="presentation_hint"/>
+ </request>
+
+ <request name="destroy" type="destructor">
+ <description summary="destroy tearing control object">
+ Destroy this surface tearing object and revert the presentation hint to
+ vsync. The change will be applied on the next wl_surface.commit.
+ </description>
+ </request>
+ </interface>
+
+</protocol>
