Zonai master (#1)

* simplify tearing implementation

---------

Co-authored-by: Andrew J. Hesford <ajh@sideband.org>

docs/labwc-config.5.scd

@@ -133,10 +133,10 @@ this is for compatibility with Openbox.
 	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.
+	*yes* allow tearing if the active window requests it.
 
-	*fullscreen* allow tearing if an open window requests it, or if any
-	window is in fullscreen mode.
+	*fullscreen* allow tearing if the active window requests it or is in
+	fullscreen mode.
 
 	*always* allow tearing regardless of window status.
 

include/config/rcxml.h

@@ -35,7 +35,7 @@ enum adaptive_sync_mode {
 };
 
 enum tearing_mode {
-	LAB_TEARING_DISABLED,
+	LAB_TEARING_DISABLED = 0,
 	LAB_TEARING_ENABLED,
 	LAB_TEARING_FULLSCREEN,
 	LAB_TEARING_ALWAYS,

include/labwc.h

@@ -361,7 +361,6 @@ struct output {
 
 	bool leased;
 	bool gamma_lut_changed;
-	bool tearing;
 };
 
 #undef LAB_NR_LAYERS
@@ -484,7 +483,6 @@ 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);

src/output.c

@@ -27,6 +27,40 @@
 #include "view.h"
 #include "xwayland.h"
 
+static bool
+get_tearing_preference(struct output *output)
+{
+	struct server *server = output->server;
+
+	/* Never allow tearing when disabled */
+	if (rc.allow_tearing == LAB_TEARING_DISABLED) {
+		return false;
+	}
+
+	/* Allows allow tearing when forced */
+	if (rc.allow_tearing == LAB_TEARING_ALWAYS) {
+		return true;
+	}
+
+	/* Tearing is only allowed for the output with the active view */
+	if (!server->active_view || server->active_view->output != output) {
+		return false;
+	}
+
+	/* If the active view requests tearing, allow it */
+	if (server->active_view->tearing_hint) {
+		return true;
+	}
+
+	/* If the active view is fullscreen, allow tearing if configured */
+	if (rc.allow_tearing == LAB_TEARING_FULLSCREEN &&
+			server->active_view->fullscreen) {
+		return true;
+	}
+
+	return false;
+}
+
 static void
 output_frame_notify(struct wl_listener *listener, void *data)
 {
@@ -68,8 +102,8 @@ output_frame_notify(struct wl_listener *listener, void *data)
 		return;
 	}
 
-	output->wlr_output->pending.tearing_page_flip = output->tearing;
-
+	output->wlr_output->pending.tearing_page_flip =
+		get_tearing_preference(output);
 	lab_wlr_scene_output_commit(output->scene_output);
 
 	struct timespec now = { 0 };
@@ -275,12 +309,6 @@ new_output_notify(struct wl_listener *listener, void *data)
 
 	wl_list_init(&output->regions);
 
-	if (rc.allow_tearing == LAB_TEARING_ALWAYS) {
-		output->tearing = true;
-	} else {
-		output->tearing = false;
-	}
-
 	/*
 	 * Create layer-trees (background, bottom, top and overlay) and
 	 * a layer-popup-tree.

src/tearing.c

@@ -48,33 +48,3 @@ new_tearing_hint(struct wl_listener *listener, void *data)
 	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;
-}

src/view.c

@@ -297,7 +297,6 @@ view_set_activated(struct view *view, bool activated)
 		}
 	}
 	set_adaptive_sync_fullscreen(view);
-	set_tearing(view->output);
 }
 
 void
@@ -1200,7 +1199,6 @@ view_set_fullscreen(struct view *view, bool fullscreen)
 		view_apply_special_geometry(view);
 	}
 	set_adaptive_sync_fullscreen(view);
-	set_tearing(view->output);
 }
 
 void