panel: Stop using Shell.GenericContainer

Shell.GenericContainer exposes the size negotiation machinery
through the use of signals. Signals are not specially performant.
One of the reasons is that they acquire a global lock for signal
handlers lookup. GNOME Shell has more than 2,000 actors at any
given point in time, up to 20 levels deep in hierarchy, making
size negotiation and painting non-trivial tasks. Such a critical
section of Clutter's machinery shouldn't rely on signals
whatsoever.

Regardless of that, Shell.GenericContainer is a workaround to
a non-existing issue anymore. It shouldn't be used anyway, and
any performance improvements that removing it can potentially
yield are bonuses to it.

This commit starts this work by removing Shell.GenericContainer
usage from Panel.Panel class. The class now extends St.Widget,
and as such, it has no "this.actor" field set anymore. A couple
of places where this actor field was used are adjuste as well.

It is important to notice that we now allocate the Panel itself
inside vfunc_allocate(). This was previously done before emitting
the signal by Shell.GenericContainer.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/153

diff --git a/js/ui/overview.js b/js/ui/overview.js
index 2418f1728a3aa7558793e976f56989789ac93f1c..35f5927a0b5c3ef70750ca3d1ac6dde17f6f8033 100644 (file)
--- a/js/ui/overview.js
+++ b/js/ui/overview.js
@@ -226,7 +226,7 @@ var Overview = new Lang.Class({
 
         // Add a clone of the panel to the overview so spacing and such is
         // automatic
-        this._panelGhost = new St.Bin({ child: new Clutter.Clone({ source: Main.panel.actor }),
+        this._panelGhost = new St.Bin({ child: new Clutter.Clone({ source: Main.panel }),
                                         reactive: false,
                                         opacity: 0 });
         this._overview.add_actor(this._panelGhost);

diff --git a/js/ui/panel.js b/js/ui/panel.js
index 3726b844509b02f0f5218a3f7cce5d82456ff379..27ebec322c632069ec7762575a01de7009c9cce9 100644 (file)
--- a/js/ui/panel.js
+++ b/js/ui/panel.js
@@ -774,12 +774,16 @@ const PANEL_ITEM_IMPLEMENTATIONS = {
 
 var Panel = new Lang.Class({
     Name: 'Panel',
+    Extends: St.Widget,
 
     _init() {
-        this.actor = new Shell.GenericContainer({ name: 'panel',
-                                                  reactive: true });
-        this.actor._delegate = this;
-        this.actor.set_offscreen_redirect(Clutter.OffscreenRedirect.ALWAYS);
+        this.parent({ name: 'panel',
+                      reactive: true });
+
+        // For compatibility with extensions that still use the
+        // this.actor field
+        this.actor = this;
+        this.set_offscreen_redirect(Clutter.OffscreenRedirect.ALWAYS);
 
         this._sessionStyle = null;
 
@@ -788,36 +792,33 @@ var Panel = new Lang.Class({
         this.menuManager = new PopupMenu.PopupMenuManager(this);
 
         this._leftBox = new St.BoxLayout({ name: 'panelLeft' });
-        this.actor.add_actor(this._leftBox);
+        this.add_child(this._leftBox);
         this._centerBox = new St.BoxLayout({ name: 'panelCenter' });
-        this.actor.add_actor(this._centerBox);
+        this.add_child(this._centerBox);
         this._rightBox = new St.BoxLayout({ name: 'panelRight' });
-        this.actor.add_actor(this._rightBox);
+        this.add_child(this._rightBox);
 
         this._leftCorner = new PanelCorner(St.Side.LEFT);
-        this.actor.add_actor(this._leftCorner.actor);
+        this.add_child(this._leftCorner.actor);
 
         this._rightCorner = new PanelCorner(St.Side.RIGHT);
-        this.actor.add_actor(this._rightCorner.actor);
+        this.add_child(this._rightCorner.actor);
 
-        this.actor.connect('get-preferred-width', this._getPreferredWidth.bind(this));
-        this.actor.connect('get-preferred-height', this._getPreferredHeight.bind(this));
-        this.actor.connect('allocate', this._allocate.bind(this));
-        this.actor.connect('button-press-event', this._onButtonPress.bind(this));
-        this.actor.connect('touch-event', this._onButtonPress.bind(this));
-        this.actor.connect('key-press-event', this._onKeyPress.bind(this));
+        this.connect('button-press-event', this._onButtonPress.bind(this));
+        this.connect('touch-event', this._onButtonPress.bind(this));
+        this.connect('key-press-event', this._onKeyPress.bind(this));
 
         Main.overview.connect('showing', () => {
-            this.actor.add_style_pseudo_class('overview');
+            this.add_style_pseudo_class('overview');
             this._updateSolidStyle();
         });
         Main.overview.connect('hiding', () => {
-            this.actor.remove_style_pseudo_class('overview');
+            this.remove_style_pseudo_class('overview');
             this._updateSolidStyle();
         });
 
-        Main.layoutManager.panelBox.add(this.actor);
-        Main.ctrlAltTabManager.addGroup(this.actor, _("Top Bar"), 'focus-top-bar-symbolic',
+        Main.layoutManager.panelBox.add(this);
+        Main.ctrlAltTabManager.addGroup(this, _("Top Bar"), 'focus-top-bar-symbolic',
                                         { sortGroup: CtrlAltTab.SortGroup.TOP });
 
         Main.sessionMode.connect('updated', this._updatePanel.bind(this));
@@ -827,7 +828,7 @@ var Panel = new Lang.Class({
         global.window_group.connect('actor-removed', this._onWindowActorRemoved.bind(this));
         global.window_manager.connect('switch-workspace', this._updateSolidStyle.bind(this));
 
-        global.display.connect('workareas-changed', () => { this.actor.queue_relayout(); });
+        global.display.connect('workareas-changed', () => { this.queue_relayout(); });
         this._updatePanel();
     },
 
@@ -847,24 +848,18 @@ var Panel = new Lang.Class({
         this._updateSolidStyle();
     },
 
-    _getPreferredWidth(actor, forHeight, alloc) {
+    vfunc_get_preferred_width(actor, forHeight) {
         let primaryMonitor = Main.layoutManager.primaryMonitor;
 
-        alloc.min_size = -1;
-
         if (primaryMonitor)
-            alloc.natural_size = primaryMonitor.width;
-        else
-            alloc.natural_size = -1;
-    },
+            return [0, primaryMonitor.width];
 
-    _getPreferredHeight(actor, forWidth, alloc) {
-        // We don't need to implement this; it's forced by the CSS
-        alloc.min_size = -1;
-        alloc.natural_size = -1;
+        return [0,  0];
     },
 
-    _allocate(actor, box, flags) {
+    vfunc_allocate(box, flags) {
+        this.parent(box, flags);
+
         let allocWidth = box.x2 - box.x1;
         let allocHeight = box.y2 - box.y1;
 
@@ -876,7 +871,7 @@ var Panel = new Lang.Class({
         centerWidth = centerNaturalWidth;
 
         // get workspace area and center date entry relative to it
-        let monitor = Main.layoutManager.findMonitorForActor(actor);
+        let monitor = Main.layoutManager.findMonitorForActor(this);
         let centerOffset = 0;
         if (monitor) {
             let workArea = Main.layoutManager.getWorkAreaForMonitor(monitor.index);
@@ -889,7 +884,7 @@ var Panel = new Lang.Class({
 
         childBox.y1 = 0;
         childBox.y2 = allocHeight;
-        if (this.actor.get_text_direction() == Clutter.TextDirection.RTL) {
+        if (this.get_text_direction() == Clutter.TextDirection.RTL) {
             childBox.x1 = Math.max(allocWidth - Math.min(Math.floor(sideWidth),
                                                          leftNaturalWidth),
                                    0);
@@ -909,7 +904,7 @@ var Panel = new Lang.Class({
 
         childBox.y1 = 0;
         childBox.y2 = allocHeight;
-        if (this.actor.get_text_direction() == Clutter.TextDirection.RTL) {
+        if (this.get_text_direction() == Clutter.TextDirection.RTL) {
             childBox.x1 = 0;
             childBox.x2 = Math.min(Math.floor(sideWidth),
                                    rightNaturalWidth);
@@ -1069,7 +1064,7 @@ var Panel = new Lang.Class({
         if (this._sessionStyle)
             this._addStyleClassName(this._sessionStyle);
 
-        if (this.actor.get_text_direction() == Clutter.TextDirection.RTL) {
+        if (this.get_text_direction() == Clutter.TextDirection.RTL) {
             this._leftCorner.setStyleParent(this._rightBox);
             this._rightCorner.setStyleParent(this._leftBox);
         } else {
@@ -1079,7 +1074,7 @@ var Panel = new Lang.Class({
     },
 
     _updateSolidStyle() {
-        if (this.actor.has_style_pseudo_class('overview') || !Main.sessionMode.hasWindows) {
+        if (this.has_style_pseudo_class('overview') || !Main.sessionMode.hasWindows) {
             this._removeStyleClassName('solid');
             return;
         }
@@ -1097,8 +1092,8 @@ var Panel = new Lang.Class({
         });
 
         /* Check if at least one window is near enough to the panel */
-        let [, panelTop] = this.actor.get_transformed_position();
-        let panelBottom = panelTop + this.actor.get_height();
+        let [, panelTop] = this.get_transformed_position();
+        let panelBottom = panelTop + this.get_height();
         let scale = St.ThemeContext.get_for_stage(global.stage).scale_factor;
         let isNearEnough = windows.some(metaWindow => {
             let verticalPosition = metaWindow.get_frame_rect().y;
@@ -1190,13 +1185,13 @@ var Panel = new Lang.Class({
     },
 
     _addStyleClassName(className) {
-        this.actor.add_style_class_name(className);
+        this.add_style_class_name(className);
         this._rightCorner.actor.add_style_class_name(className);
         this._leftCorner.actor.add_style_class_name(className);
     },
 
     _removeStyleClassName(className) {
-        this.actor.remove_style_class_name(className);
+        this.remove_style_class_name(className);
         this._rightCorner.actor.remove_style_class_name(className);
         this._leftCorner.actor.remove_style_class_name(className);
     },

diff --git a/js/ui/windowManager.js b/js/ui/windowManager.js
index cfcfa3fcb257fa532287136b01843941c3327f72..09270914ee263a465985adbe606c038fe88493b8 100644 (file)
--- a/js/ui/windowManager.js
+++ b/js/ui/windowManager.js
@@ -1796,11 +1796,11 @@ var WindowManager = new Lang.Class({
         if (direction == Meta.MotionDirection.UP ||
             direction == Meta.MotionDirection.UP_LEFT ||
             direction == Meta.MotionDirection.UP_RIGHT)
-            yDest = -global.screen_height + Main.panel.actor.height;
+            yDest = -global.screen_height + Main.panel.height;
         else if (direction == Meta.MotionDirection.DOWN ||
             direction == Meta.MotionDirection.DOWN_LEFT ||
             direction == Meta.MotionDirection.DOWN_RIGHT)
-            yDest = global.screen_height - Main.panel.actor.height;
+            yDest = global.screen_height - Main.panel.height;
 
         if (direction == Meta.MotionDirection.LEFT ||
             direction == Meta.MotionDirection.UP_LEFT ||