From c6bc1526fa080534cf587578e5a2866daed281c8 Mon Sep 17 00:00:00 2001
From: "Jasper St. Pierre" <jstpierre@mecheye.net>
Date: Sun, 4 Nov 2012 10:55:37 -0500
Subject: [PATCH] workspace: Add smooth scrolling support to zoom windows

https://bugzilla.gnome.org/show_bug.cgi?id=687573
---
 js/ui/workspace.js | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/js/ui/workspace.js b/js/ui/workspace.js
index ef7c9d62a..540c19e13 100644
--- a/js/ui/workspace.js
+++ b/js/ui/workspace.js
@@ -265,23 +265,37 @@ const WindowClone = new Lang.Class({
 
     _onScroll : function (actor, event) {
         let direction = event.get_scroll_direction();
-        if (direction == Clutter.ScrollDirection.UP) {
+        let delta;
+
+        if (event.is_pointer_emulated())
+            return;
+
+        if (direction == Clutter.ScrollDirection.DOWN) {
+            delta = -SCROLL_SCALE_AMOUNT;
+        } else if (direction == Clutter.ScrollDirection.UP) {
+            delta = +SCROLL_SCALE_AMOUNT;
+        } else if (direction == Clutter.ScrollDirection.SMOOTH) {
+            let [dx, dy] = event.get_scroll_delta();
+            delta = -dy * 10;
+        }
+
+        if (delta > 0) {
             if (this._zoomStep == undefined)
                 this._zoomStart();
             if (this._zoomStep < 100) {
-                this._zoomStep += SCROLL_SCALE_AMOUNT;
+                this._zoomStep += delta;
+                this._zoomStep = Math.min(100, this._zoomStep);
                 this._zoomUpdate();
             }
-        } else if (direction == Clutter.ScrollDirection.DOWN) {
+        } else if (delta < 0) {
             if (this._zoomStep > 0) {
-                this._zoomStep -= SCROLL_SCALE_AMOUNT;
+                this._zoomStep += delta;
                 this._zoomStep = Math.max(0, this._zoomStep);
                 this._zoomUpdate();
             }
             if (this._zoomStep <= 0.0)
                 this._zoomEnd();
         }
-
     },
 
     _zoomUpdate : function () {