[gnome-shell/wip/exalm/gestures: 9/11] workspaceAnimation: Use window clones

[Alexander Mikhaylenko <alexm src gnome org>]

commit e2a48022ea4c669c5c34a016e5cac10e1dc139cf
Author: Alexander Mikhaylenko <exalm7659 gmail com>
Date:   Thu Jul 4 23:15:15 2019 +0500

    workspaceAnimation: Use window clones
    
    Instead of reparenting windows, clone them. This will allow to properly
    support multi-monitor setups in subsequent commits.
    
    Block window mapping animation while the animation is running to prevent
    new windows appearing during the animation from being visible at the same
    time as their clones.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/605

 js/ui/workspaceAnimation.js | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)
---
diff --git a/js/ui/workspaceAnimation.js b/js/ui/workspaceAnimation.js
index f6f513f0a..81aa4106b 100644
--- a/js/ui/workspaceAnimation.js
+++ b/js/ui/workspaceAnimation.js
@@ -48,12 +48,18 @@ class WorkspaceGroup extends Clutter.Actor {
         windows = windows.filter(w => this._shouldShowWindow(w.meta_window));
 
         for (let window of windows) {
-            let record = { window: window,
-                           parent: window.get_parent() };
+            let clone = new Clutter.Clone({ source: window,
+                                            x: window.x,
+                                            y: window.y });
+
+            this.add_actor(clone);
+            window.hide();
 
-            window.reparent(this);
+            let record = { window: window,
+                           clone: clone };
 
             record.windowDestroyId = window.connect('destroy', () => {
+                clone.destroy();
                 this._windows.splice(this._windows.indexOf(record), 1);
             });
 
@@ -66,11 +72,11 @@ class WorkspaceGroup extends Clutter.Actor {
             let w = this._windows[i];
 
             w.window.disconnect(w.windowDestroyId);
-            w.window.reparent(w.parent);
+            w.clone.destroy();
 
-            if (w.window.get_meta_window().get_workspace() !=
+            if (w.window.get_meta_window().get_workspace() ==
                 global.workspace_manager.get_active_workspace())
-                w.window.hide();
+                w.window.show();
         }
 
         this._windows = [];