diff --git a/docs/labwc-config.5.scd b/docs/labwc-config.5.scd
index db01c469..81c2784f 100644
--- a/docs/labwc-config.5.scd
+++ b/docs/labwc-config.5.scd
@@ -109,6 +109,7 @@ this is for compatibility with Openbox.
server
0
no
+ no
no
```
@@ -128,6 +129,17 @@ this is for compatibility with Openbox.
*fullscreen* enables adaptive sync whenever a window is in fullscreen
mode.
+** [yes|no|fullscreen|always]
+ Allow tearing to reduce input lag. Default is no.
+ This open requires setting the environment variable WLR_DRM_NO_ATOMIC=1.
+
+ *yes* allow tearing if an open window requests it.
+
+ *fullscreen* allow tearing if an open window requests it, or if any
+ window is in fullscreen mode.
+
+ *always* allow tearing regardless of window status.
+
** [yes|no]
Try to re-use the existing output mode (resolution / refresh rate).
This may prevent unnecessary screenblank delays when starting labwc
diff --git a/include/config/rcxml.h b/include/config/rcxml.h
index 9396ebae..bb82609e 100644
--- a/include/config/rcxml.h
+++ b/include/config/rcxml.h
@@ -38,6 +38,7 @@ enum tearing_mode {
LAB_TEARING_DISABLED,
LAB_TEARING_ENABLED,
LAB_TEARING_FULLSCREEN,
+ LAB_TEARING_ALWAYS,
};
struct usable_area_override {
diff --git a/include/labwc.h b/include/labwc.h
index 74bd3fe9..1e387905 100644
--- a/include/labwc.h
+++ b/include/labwc.h
@@ -39,6 +39,7 @@
#include
#include
#include
+#include
#include
#include "config/keybind.h"
#include "config/rcxml.h"
@@ -318,6 +319,9 @@ struct server {
struct wlr_pointer_constraints_v1 *constraints;
struct wl_listener new_constraint;
+ struct wlr_tearing_control_manager_v1 *tearing_control;
+ struct wl_listener tearing_new_object;
+
/* Set when in cycle (alt-tab) mode */
struct osd_state {
struct view *cycle_view;
@@ -479,6 +483,8 @@ void handle_output_power_manager_set_mode(struct wl_listener *listener,
void output_add_virtual(struct server *server, const char *output_name);
void output_remove_virtual(struct server *server, const char *output_name);
void output_enable_adaptive_sync(struct wlr_output *output, bool enabled);
+void new_tearing_hint(struct wl_listener *listener, void *data);
+void set_tearing(struct output *output);
void server_init(struct server *server);
void server_start(struct server *server);
diff --git a/include/view.h b/include/view.h
index bef7afea..6d1c12dd 100644
--- a/include/view.h
+++ b/include/view.h
@@ -151,6 +151,7 @@ struct view {
bool minimized;
enum view_axis maximized;
bool fullscreen;
+ bool tearing_hint;
bool visible_on_all_workspaces;
enum view_edge tiled;
bool inhibits_keybinds;
diff --git a/protocols/meson.build b/protocols/meson.build
index 527f9d4c..741da7bc 100644
--- a/protocols/meson.build
+++ b/protocols/meson.build
@@ -18,6 +18,7 @@ server_protocols = [
wl_protocol_dir / 'unstable/pointer-constraints/pointer-constraints-unstable-v1.xml',
wl_protocol_dir / 'staging/cursor-shape/cursor-shape-v1.xml',
wl_protocol_dir / 'staging/drm-lease/drm-lease-v1.xml',
+ wl_protocol_dir / 'staging/tearing-control/tearing-control-v1.xml',
'wlr-layer-shell-unstable-v1.xml',
'wlr-input-inhibitor-unstable-v1.xml',
'wlr-output-power-management-unstable-v1.xml',
diff --git a/src/config/rcxml.c b/src/config/rcxml.c
index 5aa2b693..11bd7f77 100644
--- a/src/config/rcxml.c
+++ b/src/config/rcxml.c
@@ -630,6 +630,8 @@ set_tearing_mode(const char *str, enum tearing_mode *variable)
{
if (!strcasecmp(str, "fullscreen")) {
*variable = LAB_TEARING_FULLSCREEN;
+ } else if (!strcasecmp(str, "always")) {
+ *variable = LAB_TEARING_ALWAYS;
} else {
int ret = parse_bool(str, -1);
if (ret == 1) {
diff --git a/src/meson.build b/src/meson.build
index a14dc83e..baf46cb8 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -19,6 +19,7 @@ labwc_sources = files(
'server.c',
'session-lock.c',
'snap.c',
+ 'tearing.c',
'theme.c',
'view.c',
'view-impl-common.c',
diff --git a/src/output.c b/src/output.c
index 8103eea6..4319c847 100644
--- a/src/output.c
+++ b/src/output.c
@@ -68,9 +68,7 @@ output_frame_notify(struct wl_listener *listener, void *data)
return;
}
- if (output->tearing) {
- output->wlr_output->pending.tearing_page_flip = true;
- }
+ output->wlr_output->pending.tearing_page_flip = output->tearing;
lab_wlr_scene_output_commit(output->scene_output);
@@ -277,7 +275,7 @@ new_output_notify(struct wl_listener *listener, void *data)
wl_list_init(&output->regions);
- if (rc.allow_tearing == LAB_TEARING_ENABLED) {
+ if (rc.allow_tearing == LAB_TEARING_ALWAYS) {
output->tearing = true;
} else {
output->tearing = false;
diff --git a/src/server.c b/src/server.c
index e7a58be9..df4aface 100644
--- a/src/server.c
+++ b/src/server.c
@@ -449,6 +449,10 @@ server_init(struct server *server)
wl_signal_add(&server->output_power_manager_v1->events.set_mode,
&server->output_power_manager_set_mode);
+ server->tearing_control = wlr_tearing_control_manager_v1_create(server->wl_display, 1);
+ server->tearing_new_object.notify = new_tearing_hint;
+ wl_signal_add(&server->tearing_control->events.new_object, &server->tearing_new_object);
+
layers_init(server);
#if HAVE_XWAYLAND
diff --git a/src/tearing.c b/src/tearing.c
new file mode 100644
index 00000000..351994d6
--- /dev/null
+++ b/src/tearing.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "labwc.h"
+#include "view.h"
+
+struct tearing_controller {
+ struct wlr_tearing_control_v1 *tearing_control;
+ struct wl_listener set_hint;
+ struct wl_listener destroy;
+};
+
+static void
+set_tearing_hint(struct wl_listener *listener, void *data)
+{
+ struct tearing_controller *controller = wl_container_of(listener, controller, set_hint);
+ struct view *view = view_from_wlr_surface(controller->tearing_control->surface);
+ if (view) {
+ view->tearing_hint = controller->tearing_control->hint;
+ }
+}
+
+static void
+tearing_controller_destroy(struct wl_listener *listener, void *data)
+{
+ struct tearing_controller *controller = wl_container_of(listener, controller, destroy);
+ free(controller);
+}
+
+void
+new_tearing_hint(struct wl_listener *listener, void *data)
+{
+ struct server *server = wl_container_of(listener, server, tearing_new_object);
+ struct wlr_tearing_control_v1 *tearing_control = data;
+
+ enum wp_tearing_control_v1_presentation_hint hint =
+ wlr_tearing_control_manager_v1_surface_hint_from_surface
+ (server->tearing_control, tearing_control->surface);
+ wlr_log(WLR_DEBUG, "New presentation hint %d received for surface %p",
+ hint, tearing_control->surface);
+
+ struct tearing_controller *controller = calloc(1, sizeof(struct tearing_controller));
+ if (!controller) {
+ return;
+ }
+ controller->tearing_control = tearing_control;
+ controller->set_hint.notify = set_tearing_hint;
+ wl_signal_add(&tearing_control->events.set_hint, &controller->set_hint);
+ controller->destroy.notify = tearing_controller_destroy;
+ wl_signal_add(&tearing_control->events.destroy, &controller->destroy);
+}
+
+void
+set_tearing(struct output *output)
+{
+ if (rc.allow_tearing == LAB_TEARING_DISABLED) {
+ output->tearing = false;
+ return;
+ }
+
+ if (rc.allow_tearing == LAB_TEARING_ALWAYS) {
+ output->tearing = true;
+ return;
+ }
+
+ struct server *server = output->server;
+ struct view *view;
+ bool on_fullscreen = rc.allow_tearing == LAB_TEARING_FULLSCREEN;
+
+ wl_list_for_each(view, &server->views, link) {
+ if (view->output != output) {
+ continue;
+ }
+
+ if (view->tearing_hint || (on_fullscreen && view->fullscreen)) {
+ output->tearing = true;
+ return;
+ }
+ }
+ output->tearing = false;
+}
diff --git a/src/view.c b/src/view.c
index 15c6256e..09499faa 100644
--- a/src/view.c
+++ b/src/view.c
@@ -273,16 +273,6 @@ set_adaptive_sync_fullscreen(struct view *view)
wlr_output_commit(view->output->wlr_output);
}
-static void
-set_tearing_fullscreen(struct view *view)
-{
- if (rc.allow_tearing != LAB_TEARING_FULLSCREEN) {
- return;
- }
- /* Enable tearing if view is fullscreen */
- view->output->tearing = view->fullscreen;
-}
-
void
view_set_activated(struct view *view, bool activated)
{
@@ -307,7 +297,7 @@ view_set_activated(struct view *view, bool activated)
}
}
set_adaptive_sync_fullscreen(view);
- set_tearing_fullscreen(view);
+ set_tearing(view->output);
}
void
@@ -1210,7 +1200,7 @@ view_set_fullscreen(struct view *view, bool fullscreen)
view_apply_special_geometry(view);
}
set_adaptive_sync_fullscreen(view);
- set_tearing_fullscreen(view);
+ set_tearing(view->output);
}
void
@@ -1881,9 +1871,6 @@ view_destroy(struct view *view)
if (rc.adaptive_sync == LAB_ADAPTIVE_SYNC_FULLSCREEN) {
wlr_output_enable_adaptive_sync(view->output->wlr_output, false);
}
- if (rc.allow_tearing == LAB_TEARING_FULLSCREEN) {
- view->output->tearing = false;
- }
}
/* If we spawned a window menu, close it */