ash: Add some experimental support for gesture-fling to snap/minimize/maximize windows.

BUG=121140
TEST=none

Review URL: https://chromiumcodereview.appspot.com/10067011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@132042 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 49 insertions, 13 deletions

diff --git a/ash/wm/default_window_resizer.h b/ash/wm/default_window_resizer.h
index 0f6494b..ea7d114 100644
--- a/ash/wm/default_window_resizer.h
+++ b/ash/wm/default_window_resizer.h
@@ -20,16 +20,6 @@ class RootWindowEventFilter;
 // windows coordiantes.
 class ASH_EXPORT DefaultWindowResizer : public WindowResizer {
  public:
-  // Constants to identify the type of resize.
-  static const int kBoundsChange_None;
-  static const int kBoundsChange_Repositions;
-  static const int kBoundsChange_Resizes;
-
-  // Used to indicate which direction the resize occurs in.
-  static const int kBoundsChangeDirection_None;
-  static const int kBoundsChangeDirection_Horizontal;
-  static const int kBoundsChangeDirection_Vertical;
-
   virtual ~DefaultWindowResizer();
 
   // Creates a new DefaultWindowResizer. The caller takes ownership of the
@@ -42,6 +32,11 @@ class ASH_EXPORT DefaultWindowResizer : public WindowResizer {
   // Returns true if the drag will result in changing the window in anyway.
   bool is_resizable() const { return details_.is_resizable; }
 
+  bool changed_size() const {
+    return !(details_.bounds_change & kBoundsChange_Repositions);
+  }
+  aura::Window* target_window() const { return details_.window; }
+
   // WindowResizer overides:
   virtual void Drag(const gfx::Point& location) OVERRIDE;
   virtual void CompleteDrag() OVERRIDE;
diff --git a/ash/wm/toplevel_window_event_filter.cc b/ash/wm/toplevel_window_event_filter.cc
index 962698ff..53e388f 100644
--- a/ash/wm/toplevel_window_event_filter.cc
+++ b/ash/wm/toplevel_window_event_filter.cc
@@ -10,6 +10,7 @@
 #include "ash/wm/resize_shadow_controller.h"
 #include "ash/wm/window_resizer.h"
 #include "ash/wm/window_util.h"
+#include "ash/wm/workspace/snap_sizer.h"
 #include "base/message_loop.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/env.h"
@@ -20,8 +21,15 @@
 #include "ui/base/cursor/cursor.h"
 #include "ui/base/hit_test.h"
 #include "ui/base/ui_base_types.h"
+#include "ui/gfx/compositor/layer.h"
+#include "ui/gfx/compositor/scoped_layer_animation_settings.h"
 #include "ui/gfx/screen.h"
 
+namespace {
+const double kMinHorizVelocityForWindowSwipe = 1100;
+const double kMinVertVelocityForWindowMinimize = 1000;
+}
+
 namespace ash {
 
 namespace {
@@ -142,7 +150,40 @@ ui::GestureStatus ToplevelWindowEventFilter::PreHandleGestureEvent(
     case ui::ET_GESTURE_SCROLL_END: {
       if (!in_gesture_resize_)
         return ui::GESTURE_STATUS_UNKNOWN;
-      CompleteDrag(DRAG_COMPLETE);
+      DefaultWindowResizer* default_resizer =
+          static_cast<DefaultWindowResizer*>(window_resizer_.get());
+      bool changed_size =
+          default_resizer ?  default_resizer->changed_size() : false;
+      aura::Window* window =
+          default_resizer ?  default_resizer->target_window() : NULL;
+      bool drag_done = false;
+
+      if (window && !changed_size) {
+        if (fabs(event->delta_y()) > kMinVertVelocityForWindowMinimize) {
+          // Minimize/maximize.
+          window->SetProperty(aura::client::kShowStateKey,
+              event->delta_y() > 0 ? ui::SHOW_STATE_MINIMIZED :
+                                     ui::SHOW_STATE_MAXIMIZED);
+          drag_done = true;
+        } else if (fabs(event->delta_x()) > kMinHorizVelocityForWindowSwipe) {
+          // Snap left/right.
+          internal::SnapSizer sizer(window,
+              gfx::Point(),
+              event->delta_x() < 0 ? internal::SnapSizer::LEFT_EDGE :
+              internal::SnapSizer::RIGHT_EDGE,
+              Shell::GetInstance()->GetGridSize());
+
+          ui::ScopedLayerAnimationSettings scoped_setter(
+              window->layer()->GetAnimator());
+          scoped_setter.SetPreemptionStrategy(
+              ui::LayerAnimator::REPLACE_QUEUED_ANIMATIONS);
+          window->SetBounds(sizer.target_bounds());
+          drag_done = true;
+        }
+      }
+
+      if (!drag_done)
+        CompleteDrag(DRAG_COMPLETE);
       in_gesture_resize_ = false;
       break;
     }
diff --git a/ui/base/animation/tween.cc b/ui/base/animation/tween.cc
index b8f4385..c1e4a47 100644
--- a/ui/base/animation/tween.cc
+++ b/ui/base/animation/tween.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -37,7 +37,7 @@ double Tween::CalculateValue(Tween::Type type, double state) {
 
     case EASE_OUT_SNAP:
       state = 0.95 * (1.0 - pow(1.0 - state, 2));
-      break;
+      return state;
 
     case EASE_OUT:
       return 1.0 - pow(1.0 - state, 2);