LayoutManager: implement new design for the startup animation

The design calls for two different startup animations, in the GDM
and in the normal session case.
In both cases, we implement fading from the previous situation
by acquiring the root background pixmap and turning it into a TFP
texture, which is then animated and blended by Clutter as normal.

https://bugzilla.gnome.org/show_bug.cgi?id=682429

js/ui/layout.js

@@ -1,6 +1,7 @@
 // -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
 
 const Clutter = imports.gi.Clutter;
+const ClutterX11 = imports.gi.ClutterX11;
 const GObject = imports.gi.GObject;
 const Lang = imports.lang;
 const Mainloop = imports.mainloop;
@@ -15,9 +16,9 @@ const Params = imports.misc.params;
 const Tweener = imports.ui.tweener;
 
 const HOT_CORNER_ACTIVATION_TIMEOUT = 0.5;
-const STARTUP_ANIMATION_TIME = 0.2;
+const STARTUP_ANIMATION_TIME = 1;
 const KEYBOARD_ANIMATION_TIME = 0.15;
-const PLYMOUTH_TRANSITION_TIME = 1;
+const DEFAULT_BACKGROUND_COLOR = Clutter.Color.from_pixel(0x2e3436ff);
 
 const MonitorConstraint = new Lang.Class({
     Name: 'MonitorConstraint',
@@ -111,7 +112,6 @@ const LayoutManager = new Lang.Class({
         this.primaryIndex = -1;
         this._keyboardIndex = -1;
         this._hotCorners = [];
-        this._background = null;
         this._leftPanelBarrier = 0;
         this._rightPanelBarrier = 0;
 
@@ -120,6 +120,42 @@ const LayoutManager = new Lang.Class({
 
         this._trackedActors = [];
 
+        // Normally, the stage is always covered so Clutter doesn't need to clear
+        // it; however it becomes visible during the startup animation
+        // See the comment below for a longer explanation
+        global.stage.color = DEFAULT_BACKGROUND_COLOR;
+
+        // Set up stage hierarchy to group all UI actors under one container.
+        this.uiGroup = new Shell.GenericContainer({ name: 'uiGroup' });
+        this.uiGroup.connect('allocate',
+                        function (actor, box, flags) {
+                            let children = actor.get_children();
+                            for (let i = 0; i < children.length; i++)
+                                children[i].allocate_preferred_size(flags);
+                        });
+        this.uiGroup.connect('get-preferred-width',
+                        function(actor, forHeight, alloc) {
+                            let width = global.stage.width;
+                            [alloc.min_size, alloc.natural_size] = [width, width];
+                        });
+        this.uiGroup.connect('get-preferred-height',
+                        function(actor, forWidth, alloc) {
+                            let height = global.stage.height;
+                            [alloc.min_size, alloc.natural_size] = [height, height];
+                        });
+
+        global.window_group.reparent(this.uiGroup);
+
+        // Now, you might wonder why we went through all the hoops to implement
+        // the GDM greeter inside an X11 compositor, to do this at the end...
+        // However, hiding this is necessary to avoid showing the background during
+        // the initial animation, before Gdm.LoginDialog covers everything
+        if (Main.sessionMode.isGreeter)
+            global.window_group.hide();
+
+        global.overlay_group.reparent(this.uiGroup);
+        global.stage.add_child(this.uiGroup);
+
         this.screenShieldGroup = new St.Widget({ name: 'screenShieldGroup',
                                                  visible: false,
                                                  clip_to_allocation: true,
@@ -161,7 +197,8 @@ const LayoutManager = new Lang.Class({
         Main.overview.connect('showing', Lang.bind(this, this._overviewShowing));
         Main.overview.connect('hidden', Lang.bind(this, this._overviewHidden));
         Main.sessionMode.connect('updated', Lang.bind(this, this._sessionUpdated));
-        this._startupAnimation();
+
+        this._prepareStartupAnimation();
     },
 
     _overviewShowing: function() {
@@ -254,7 +291,7 @@ const LayoutManager = new Lang.Class({
             if (!haveTopLeftCorner)
                 continue;
 
-            let corner = new HotCorner();
+            let corner = new HotCorner(this);
             this._hotCorners.push(corner);
             corner.actor.set_position(cornerX, cornerY);
             this.addChrome(corner.actor);
@@ -376,51 +413,106 @@ const LayoutManager = new Lang.Class({
         return this._keyboardIndex;
     },
 
-    _startupAnimation: function() {
-        this.panelBox.translation_y = -this.panelBox.height;
+    _acquireRootBackground: function() {
+        let rootpmap = Shell.util_get_root_background();
+        let texture = ClutterX11.TexturePixmap.new_with_pixmap(rootpmap);
+        // The texture size might not match the screen size, for example
+        // if the session has a different XRandR configuration than the greeter
+        texture.x = 0;
+        texture.y = 0;
+        texture.width = global.screen_width;
+        texture.height = global.screen_height;
+        texture.set_automatic(true);
 
-        let plymouthTransitionRunning = false;
-
-        // If we're the greeter, put up the xrootpmap actor
-        // and fade it out to have a nice transition from plymouth
-        // to the greeter. Otherwise, we'll just animate the panel,
-        // as usual.
-        if (Main.sessionMode.isGreeter) {
-            this._background = Meta.BackgroundActor.new_for_screen(global.screen);
-            if (this._background != null) {
-                Main.uiGroup.add_actor(this._background);
-                Tweener.addTween(this._background,
-                                 { opacity: 0,
-                                   time: PLYMOUTH_TRANSITION_TIME,
-                                   transition: 'linear',
-                                   onComplete: this._fadeBackgroundComplete,
-                                   onCompleteScope: this });
-                plymouthTransitionRunning = true;
-            }
-        }
-
-        if (!plymouthTransitionRunning)
-            this._fadeBackgroundComplete();
+        this._rootTexture = texture;
     },
 
-    _fadeBackgroundComplete: function() {
+    // Startup Animations
+    //
+    // We have two different animations, depending on whether we're a greeter
+    // or a normal session.
+    //
+    // In the greeter, we want to animate the panel from the top, and smoothly
+    // fade the login dialog on top of whatever plymouth left on screen, which we
+    // grab as a X11 texture_from_pixmap.
+    // Here we just have the code to animate the panel, the login dialog animation
+    // is handled by modalDialog.js
+    //
+    // In a normal session, we want to take the root background, which now holds
+    // the final frame of the GDM greeter, and slide it from the bottom, while
+    // at the same time scaling the UI contents of the new shell on top of the
+    // stage background.
+    //
+    // Usually, we don't want to paint the stage background color because the
+    // MetaBackgroundActor inside global.window_group covers the entirety of the
+    // screen. So, we set no_clear_hint at the end of the animation.
+
+    _prepareStartupAnimation: function() {
+        // Set ourselves to FULLSCREEN input mode while the animation is running
+        // so events don't get delivered to X11 windows (which are distorted by the animation)
+        global.stage_input_mode = Shell.StageInputMode.FULLSCREEN;
+
+        this._acquireRootBackground();
+
+        if (Main.sessionMode.isGreeter) {
+            global.stage.insert_child_below(this._rootTexture, null);
+
+            this._panelBox.translation_y = -this._panelBox.height;
+        } else {
+            global.stage.insert_child_above(this._rootTexture, null);
+
+            this.uiGroup.set_pivot_point(0.5, 0.5);
+            this.uiGroup.scale_x = this.uiGroup.scale_y = 0;
+        }
+    },
+
+    startupAnimation: function() {
+        if (Main.sessionMode.isGreeter)
+            this._startupAnimationGreeter();
+        else
+            this._startupAnimationSession();
+    },
+
+    _startupAnimationGreeter: function() {
+        // Don't animate the strut
         this._freezeUpdateRegions();
 
-        if (this._background != null) {
-            this._background.destroy();
-            this._background = null;
-        }
-
-        Tweener.addTween(this.panelBox,
+        Tweener.addTween(this._panelBox,
                          { translation_y: 0,
                            time: STARTUP_ANIMATION_TIME,
                            transition: 'easeOutQuad',
                            onComplete: this._startupAnimationComplete,
-                           onCompleteScope: this
-                         });
+                           onCompleteScope: this });
+    },
+
+    _startupAnimationSession: function() {
+        // Don't animate the strut
+        this._freezeUpdateRegions();
+
+        Tweener.addTween(this._rootTexture,
+                         { translation_y: -global.screen_height,
+                           time: STARTUP_ANIMATION_TIME,
+                           transition: 'linear' });
+
+        Tweener.addTween(this.uiGroup,
+                         { scale_x: 1,
+                           scale_y: 1,
+                           time: STARTUP_ANIMATION_TIME,
+                           transition: 'easeOutQuad',
+                           onComplete: this._startupAnimationComplete,
+                           onCompleteScope: this });
     },
 
     _startupAnimationComplete: function() {
+        // At this point, the UI group is covering everything, so
+        // we no longer need to clear the stage
+        global.stage.no_clear_hint = true;
+
+        global.stage_input_mode = Shell.StageInputMode.NORMAL;
+
+        this._rootTexture.destroy();
+        this._rootTexture = null;
+
         this.emit('panel-box-changed');
         this._thawUpdateRegions();
     },
@@ -506,7 +598,7 @@ const LayoutManager = new Lang.Class({
     // monitor (it will be hidden whenever a fullscreen window is visible,
     // and shown otherwise)
     addChrome: function(actor, params) {
-        Main.uiGroup.add_actor(actor);
+        this.uiGroup.add_actor(actor);
         this._trackActor(actor, params);
     },
 
@@ -557,7 +649,7 @@ const LayoutManager = new Lang.Class({
     //
     // Removes @actor from the chrome
     removeChrome: function(actor) {
-        Main.uiGroup.remove_actor(actor);
+        this.uiGroup.remove_actor(actor);
         this._untrackActor(actor);
     },
 
@@ -576,7 +668,7 @@ const LayoutManager = new Lang.Class({
 
         let actorData = Params.parse(params, defaultParams);
         actorData.actor = actor;
-        actorData.isToplevel = actor.get_parent() == Main.uiGroup;
+        actorData.isToplevel = actor.get_parent() == this.uiGroup;
         actorData.visibleId = actor.connect('notify::visible',
                                             Lang.bind(this, this._queueUpdateRegions));
         actorData.allocationId = actor.connect('notify::allocation',
@@ -612,7 +704,7 @@ const LayoutManager = new Lang.Class({
         } else {
             let i = this._findActor(actor);
             let actorData = this._trackedActors[i];
-            actorData.isToplevel = (newParent == Main.uiGroup);
+            actorData.isToplevel = (newParent == this.uiGroup);
         }
     },
 
@@ -812,7 +904,7 @@ const LayoutManager = new Lang.Class({
 
             if (actorData.affectsInputRegion &&
                 actorData.actor.get_paint_visibility() &&
-                !Main.uiGroup.get_skip_paint(actorData.actor))
+                !this.uiGroup.get_skip_paint(actorData.actor))
                 rects.push(rect);
 
             if (!actorData.affectsStruts)

js/ui/main.js

@@ -38,7 +38,6 @@ const XdndHandler = imports.ui.xdndHandler;
 const Util = imports.misc.util;
 
 const OVERRIDES_SCHEMA = 'org.gnome.shell.overrides';
-const DEFAULT_BACKGROUND_COLOR = Clutter.Color.from_pixel(0x2e3436ff);
 
 let componentManager = null;
 let panel = null;
@@ -63,6 +62,7 @@ let magnifier = null;
 let xdndHandler = null;
 let keyboard = null;
 let layoutManager = null;
+let background = null;
 let _startDate;
 let _defaultCssStylesheet = null;
 let _cssStylesheet = null;
@@ -111,38 +111,17 @@ function start() {
 
     tracker.connect('startup-sequence-changed', _queueCheckWorkspaces);
 
-    // The stage is always covered so Clutter doesn't need to clear it; however
-    // the color is used as the default contents for the Mutter root background
-    // actor so set it anyways.
-    global.stage.color = DEFAULT_BACKGROUND_COLOR;
-    global.stage.no_clear_hint = true;
+    // Setup the stage hierarchy early
+    layoutManager = new Layout.LayoutManager();
+    // For backward compatibility
+    uiGroup = layoutManager.uiGroup;
+
+    let backgroundActor = global.window_group.background;
+    background = backgroundActor.settings;
 
     _defaultCssStylesheet = global.datadir + '/theme/gnome-shell.css';
     loadTheme();
 
-    // Set up stage hierarchy to group all UI actors under one container.
-    uiGroup = new Shell.GenericContainer({ name: 'uiGroup' });
-    uiGroup.connect('allocate',
-                    function (actor, box, flags) {
-                        let children = uiGroup.get_children();
-                        for (let i = 0; i < children.length; i++)
-                            children[i].allocate_preferred_size(flags);
-                    });
-    uiGroup.connect('get-preferred-width',
-                    function(actor, forHeight, alloc) {
-                        let width = global.stage.width;
-                        [alloc.min_size, alloc.natural_size] = [width, width];
-                    });
-    uiGroup.connect('get-preferred-height',
-                    function(actor, forWidth, alloc) {
-                        let height = global.stage.height;
-                        [alloc.min_size, alloc.natural_size] = [height, height];
-                    });
-    global.window_group.reparent(uiGroup);
-    global.overlay_group.reparent(uiGroup);
-    global.stage.add_actor(uiGroup);
-
-    layoutManager = new Layout.LayoutManager();
     xdndHandler = new XdndHandler.XdndHandler();
     ctrlAltTabManager = new CtrlAltTab.CtrlAltTabManager();
     overview = new Overview.Overview();
@@ -196,6 +175,14 @@ function start() {
 
     ExtensionDownloader.init();
     ExtensionSystem.init();
+
+    // Run the startup animation as soon as the mainloop is idle enough
+    // This is necessary to have it smooth and without interruptions from
+    // completed IO tasks
+    GLib.idle_add(GLib.PRIORITY_LOW, function() {
+        layoutManager.startupAnimation();
+        return false;
+    });
 }
 
 let _workspaces = [];

js/ui/overview.js

@@ -122,7 +122,8 @@ const Overview = new Lang.Class({
         // one. Instances of this class share a single CoglTexture behind the
         // scenes which allows us to show the background with different
         // rendering options without duplicating the texture data.
-        this._background = Meta.BackgroundActor.new_for_screen(global.screen);
+        this._background = new Meta.BackgroundActor({ screen: global.screen,
+                                                      settings: Main.background });
         this._background.add_glsl_snippet(Meta.SnippetHook.FRAGMENT,
                                           GLSL_DIM_EFFECT_DECLARATIONS,
                                           GLSL_DIM_EFFECT_CODE,

js/ui/panel.js

@@ -644,7 +644,7 @@ const ActivitiesButton = new Lang.Class({
 
         this.actor.label_actor = this._label;
 
-        this.hotCorner = new Layout.HotCorner();
+        this.hotCorner = new Layout.HotCorner(Main.layoutManager);
         container.add_actor(this.hotCorner.actor);
 
         this.actor.connect('captured-event', Lang.bind(this, this._onCapturedEvent));

js/ui/screenShield.js

@@ -52,36 +52,16 @@ const SUMMARY_ICON_SIZE = 48;
 const STANDARD_FADE_TIME = 10;
 const SHORT_FADE_TIME = 0.3;
 
-function sample(offx, offy) {
-    return 'texel += texture2D (sampler, tex_coord.st + pixel_step * ' +
-        'vec2 (' + offx + ',' + offy + '));\n'
-}
-const GLSL_BLUR_EFFECT_DECLARATIONS = ' \
-uniform vec2 pixel_step;\n \
+const GLSL_EFFECT_DECLARATIONS = ' \
 uniform float desaturation; \n \
-vec4 apply_blur(in sampler2D sampler, in vec2 tex_coord) {\n \
-  vec4 texel;\n \
-  texel = texture2D (sampler, tex_coord.st);\n'
-  + sample(-1.0, -1.0)
-  + sample( 0.0, -1.0)
-  + sample(+1.0, -1.0)
-  + sample(-1.0,  0.0)
-  + sample(+1.0,  0.0)
-  + sample(-1.0, +1.0)
-  + sample( 0.0, +1.0)
-  + sample(+1.0, +1.0) + ' \
-   texel /= 9.0;\n \
-   return texel;\n \
-}\n \
 vec3 desaturate (const vec3 color)\n \
 {\n \
    const vec3 gray_conv = vec3 (0.299, 0.587, 0.114);\n \
    vec3 gray = vec3 (dot (gray_conv, color));\n \
    return vec3 (mix (color.rgb, gray, desaturation));\n \
 }';
-const GLSL_BLUR_EFFECT_CODE = ' \
-cogl_texel = apply_blur(cogl_sampler, cogl_tex_coord.st);\n \
-cogl_texel.rgb = desaturate(cogl_texel.rgb);\n';
+const GLSL_EFFECT_CODE = ' \
+cogl_color_out.rgb = desaturate(cogl_color_out.rgb);\n';
 
 
 const Clock = new Lang.Class({
@@ -467,16 +447,16 @@ const ScreenShield = new Lang.Class({
                                                    name: 'lockScreenContents' });
         this._lockScreenContents.add_constraint(new Layout.MonitorConstraint({ primary: true }));
 
-        let backgroundActor = Meta.BackgroundActor.new_for_screen(global.screen);
-        backgroundActor.add_glsl_snippet(Meta.SnippetHook.TEXTURE_LOOKUP,
-                                         GLSL_BLUR_EFFECT_DECLARATIONS,
-                                         GLSL_BLUR_EFFECT_CODE,
-                                         true);
+        this._settings = new Gio.Settings({ schema: SCREENSAVER_SCHEMA });
+
+        let backgroundActor = new Meta.BackgroundActor({ screen: global.screen,
+                                                         settings: this._settings });
+        backgroundActor.add_glsl_snippet(Meta.SnippetHook.FRAGMENT,
+                                         GLSL_EFFECT_DECLARATIONS,
+                                         GLSL_EFFECT_CODE,
+                                         false);
         backgroundActor.set_uniform_float('desaturation',
                                           1, 1, [0.6]);
-        backgroundActor.connect('notify::size', function(actor) {
-            actor.set_uniform_float('pixel_step', 2, 1, [1/actor.width, 1/actor.height]);
-        });
 
         this._background = new St.Bin({ style_class: 'screen-shield-background',
                                         child: backgroundActor });
@@ -531,8 +511,6 @@ const ScreenShield = new Lang.Class({
         this._loginSession.connectSignal('Lock', Lang.bind(this, function() { this.lock(false); }));
         this._loginSession.connectSignal('Unlock', Lang.bind(this, function() { this.deactivate(false); }));
 
-        this._settings = new Gio.Settings({ schema: SCREENSAVER_SCHEMA });
-
         this._isModal = false;
         this._hasLockScreen = false;
         this._isGreeter = false;

js/ui/workspaceThumbnail.js

@@ -170,7 +170,8 @@ const WorkspaceThumbnail = new Lang.Class({
 
         this.actor.connect('destroy', Lang.bind(this, this._onDestroy));
 
-        this._background = Meta.BackgroundActor.new_for_screen(global.screen);
+        this._background = new Meta.BackgroundActor({ screen: global.screen,
+                                                      settings: Main.background });
         this._contents.add_actor(this._background);
 
         let monitor = Main.layoutManager.primaryMonitor;

src/Makefile.am

@@ -292,7 +292,7 @@ libgnome_shell_la_LIBADD =		\
 libgnome_shell_la_CPPFLAGS = $(gnome_shell_cflags)
 
 Shell-0.1.gir: libgnome-shell.la St-1.0.gir
-Shell_0_1_gir_INCLUDES = Clutter-1.0 ClutterX11-1.0 Meta-3.0 TelepathyGLib-0.12 TelepathyLogger-0.2 Soup-2.4 GMenu-3.0 NetworkManager-1.0 NMClient-1.0
+Shell_0_1_gir_INCLUDES = Clutter-1.0 ClutterX11-1.0 Meta-3.0 TelepathyGLib-0.12 TelepathyLogger-0.2 Soup-2.4 GMenu-3.0 NetworkManager-1.0 NMClient-1.0 xlib-2.0
 Shell_0_1_gir_CFLAGS = $(libgnome_shell_la_CPPFLAGS) -I $(srcdir)
 Shell_0_1_gir_LIBS = libgnome-shell.la
 Shell_0_1_gir_FILES = $(libgnome_shell_la_gir_sources)

src/shell-util.c

@@ -9,6 +9,8 @@
 #include <glib/gi18n-lib.h>
 #include <gtk/gtk.h>
 #include <gdk-pixbuf/gdk-pixbuf.h>
+#include <gdk/gdkx.h>
+#include <X11/Xatom.h>
 
 #ifdef HAVE__NL_TIME_FIRST_WEEKDAY
 #include <langinfo.h>
@@ -430,3 +432,56 @@ shell_util_create_pixbuf_from_data (const guchar      *data,
                                    bits_per_sample, width, height, rowstride,
                                    (GdkPixbufDestroyNotify) g_free, NULL);
 }
+
+Pixmap
+shell_util_get_root_background (void)
+{
+  Display *display;
+  Pixmap pixmap;
+  Window rootwin;
+  Atom xrootpmap;
+  Atom actual_type;
+  int actual_format;
+  unsigned long n_items;
+  unsigned long bytes_after;
+  unsigned char *buffer;
+
+  display = gdk_x11_get_default_xdisplay ();
+
+  xrootpmap = gdk_x11_atom_to_xatom (gdk_atom_intern_static_string ("_XROOTPMAP_ID"));
+  rootwin = gdk_x11_get_default_root_xwindow ();
+
+  gdk_error_trap_push ();
+  actual_type = None;
+  buffer = NULL;
+  if (XGetWindowProperty (display, rootwin, xrootpmap,
+                          0, G_MAXLONG,
+                          False, XA_PIXMAP, &actual_type, &actual_format,
+                          &n_items,
+                          &bytes_after,
+                          &buffer) != Success ||
+      actual_type == None)
+    {
+      if (buffer)
+        XFree (buffer);
+      gdk_error_trap_pop_ignored ();
+      return FALSE;
+    }
+
+  if (gdk_error_trap_pop () != Success ||
+      n_items == 0 ||
+      actual_type != XA_PIXMAP ||
+      actual_format != 32)
+    {
+      if (buffer)
+        XFree (buffer);
+      return FALSE;
+    }
+
+  pixmap = *((Pixmap*) buffer);
+
+  XFree (buffer);
+  return pixmap;
+}
+
+

src/shell-util.h

@@ -7,6 +7,7 @@
 #include <clutter/clutter.h>
 #include <libsoup/soup.h>
 #include <gdk-pixbuf/gdk-pixbuf.h>
+#include <gdk/gdkx.h>
 
 G_BEGIN_DECLS
 
@@ -46,6 +47,8 @@ GdkPixbuf *shell_util_create_pixbuf_from_data (const guchar      *data,
                                                int                height,
                                                int                rowstride);
 
+Pixmap  shell_util_get_root_background        (void);
+
 G_END_DECLS
 
 #endif /* __SHELL_UTIL_H__ */