From 04a219f6df7f4a52d411adfc6ced27b8a59d75cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tor=20Hedin=20Br=C3=B8nner?= <torhedinbronner@gmail.com>
Date: Sat, 15 Sep 2018 18:15:59 +0200
Subject: [PATCH] animateToSpace: Split up animation and hiding of spaces

The code here tried to serve two purposes, animating spaces above the newly
selected space and hiding spaces that would no longer be visible. Hiding
probably never worked as the loop wouldn't touch all spaces.

We split it up properly, fixing the performance bug mentioned in the parent.
While properly handling animation on its own.
---
 tiling.js | 54 +++++++++++++++++++++++++++++-------------------------
 1 file changed, 29 insertions(+), 25 deletions(-)

diff --git a/tiling.js b/tiling.js
index 4886b82..048927b 100644
--- a/tiling.js
+++ b/tiling.js
@@ -1145,13 +1145,16 @@ class Spaces extends Map {
 
             space.actor.scale_y = scale - i*0.01;
             space.actor.scale_x = scale - i*0.01;
+
+            // Remove any lingering onComplete handlers from animateToSpace
+            Tweener.removeTweens(space.actor);
+
             if (mru[i - 1] === undefined)
                 return;
             cloneParent.set_child_below_sibling(
                 space.clip,
                 mru[i - 1].clip
             );
-            Tweener.removeTweens(space.actor);
             space.actor.show();
 
             let selected = space.selectedWindow;
@@ -1265,8 +1268,6 @@ class Spaces extends Map {
         });
         this._moving = [];
 
-        let xDest = 0, yDest = global.screen_height;
-
         this.selectedSpace = to;
 
         to.actor.show();
@@ -1278,6 +1279,12 @@ class Spaces extends Map {
             from.startAnimate();
         }
 
+
+        let visible = new Map();
+        for (let [monitor, space] of this.monitors) {
+            visible.set(space, true);
+        }
+
         Tweener.addTween(to.actor,
                          { x: 0,
                            y: 0,
@@ -1288,36 +1295,33 @@ class Spaces extends Map {
                            onComplete: () => {
                                // Meta.enable_unredirect_for_screen(screen);
 
+                               // Hide any spaces that aren't visible This
+                               // avoids a nasty permance degregration in some
+                               // cases
+                               for (const space of spaces.values()) {
+                                   if (!visible.get(space)) {
+                                       space.actor.hide();
+                                   }
+                               }
+
                                to.moveDone();
                                to.clip.raise_top();
                                callback && callback();
                            }
                          });
 
-        let visible = new Map();
-        for (let [monitor, space] of this.monitors) {
-            visible.set(space, true);
-        }
-
-        let scale = 0.9;
-        for (const space of spaces.values()) {
+        // Animate all the spaces above `to` down below the monitor. We get
+        // these spaces by looking at siblings of upper most actor, ie. the
+        // `clip`. This is done since `this.stack` is already updated.
+        let above = to.clip.get_next_sibling();
+        while (above) {
+            let space = above.space;
             if (!visible.get(space)) {
-                Tweener.addTween(
-                    space.clip,
-                    { x: xDest,
-                      y: yDest,
-                      scale_x: scale,
-                      scale_y: scale,
-                      time: 0.25,
-                      transition: 'easeInOutQuad',
-                      onComplete() {
-                          this.set_position(0, global.screen_height*0.1);
-                          this.hide();
-                      },
-                      onCompleteScope: space.clip.first_child
-                    });
-
+                Tweener.addTween(space.actor,
+                                 {x: 0, y: space.height + 20,
+                                  time: 0.25, transition: 'easeInOutQuad' });
             }
+            above = above.get_next_sibling();
         }
     }