Cros splitscreen: Animate the overview window to its snapped position.

Define SPLITVIEW_ANIMATION_RESTORE_OVERVIEW_WINDOW. And also animate the
overview window from its position in overview grid to its snapped postion.

Bug: 822486
Change-Id: I64a48b33012c428a5529dfea58f048f30c043e73
Reviewed-on: https://chromium-review.googlesource.com/972562Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Commit-Queue: Xiaoqian Dai <xdai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545580}

ash/wm/overview/overview_window_drag_controller.cc

@@ -303,8 +303,9 @@ void OverviewWindowDragController::SnapWindow(
 
   // |item_| will be deleted after RemoveWindowSelectorItem().
   aura::Window* window = item_->GetWindow();
+  const gfx::Rect item_bounds = item_->target_bounds();
   window_selector_->RemoveWindowSelectorItem(item_);
-  split_view_controller_->SnapWindow(window, snap_position);
+  split_view_controller_->SnapWindow(window, snap_position, item_bounds);
   item_ = nullptr;
 }
 

ash/wm/overview/window_selector_controller.cc

@@ -231,8 +231,10 @@ void WindowSelectorController::OnOverviewButtonTrayLongPressed(
   // The transform will be reset later after the window is snapped.
   item_to_snap->RestoreWindow(/*reset_transform=*/false);
   aura::Window* window = item_to_snap->GetWindow();
+  const gfx::Rect item_bounds = item_to_snap->target_bounds();
   window_selector_->RemoveWindowSelectorItem(item_to_snap);
-  split_view_controller->SnapWindow(window, SplitViewController::LEFT);
+  split_view_controller->SnapWindow(window, SplitViewController::LEFT,
+                                    item_bounds);
   window_selector_->SetBoundsForWindowGridsInScreen(
       split_view_controller->GetSnappedWindowBoundsInScreen(
           window, SplitViewController::RIGHT));

ash/wm/splitview/split_view_controller.cc

@@ -17,11 +17,11 @@
 #include "ash/system/toast/toast_data.h"
 #include "ash/system/toast/toast_manager.h"
 #include "ash/wm/mru_window_tracker.h"
-#include "ash/wm/overview/scoped_overview_animation_settings.h"
 #include "ash/wm/overview/window_grid.h"
 #include "ash/wm/overview/window_selector_controller.h"
 #include "ash/wm/overview/window_selector_item.h"
 #include "ash/wm/splitview/split_view_divider.h"
+#include "ash/wm/splitview/split_view_utils.h"
 #include "ash/wm/tablet_mode/tablet_mode_controller.h"
 #include "ash/wm/window_state.h"
 #include "ash/wm/window_transient_descendant_iterator.h"
@@ -204,7 +204,8 @@ bool SplitViewController::IsCurrentScreenOrientationPrimary() const {
 }
 
 void SplitViewController::SnapWindow(aura::Window* window,
-                                     SnapPosition snap_position) {
+                                     SnapPosition snap_position,
+                                     const gfx::Rect& window_item_bounds) {
   DCHECK(window && CanSnap(window));
   DCHECK_NE(snap_position, NONE);
 
@@ -237,6 +238,9 @@ void SplitViewController::SnapWindow(aura::Window* window,
   }
   StartObserving(window);
 
+  if (!window_item_bounds.IsEmpty())
+    overview_window_item_bounds_map_[window] = window_item_bounds;
+
   // Update the divider position and window bounds before snapping a new window.
   // Since the minimum size of |window| maybe larger than currently bounds in
   // |snap_position|.
@@ -474,6 +478,7 @@ void SplitViewController::EndSplitView() {
   black_scrim_layer_.reset();
   default_snap_position_ = NONE;
   divider_position_ = -1;
+  overview_window_item_bounds_map_.clear();
 
   UpdateSplitViewStateAndNotifyObservers();
   base::RecordAction(base::UserMetricsAction("SplitView_EndSplitView"));
@@ -500,6 +505,9 @@ void SplitViewController::OnWindowDestroying(aura::Window* window) {
   DCHECK(window == left_window_ || window == right_window_);
   if (smooth_resize_window_ == window)
     smooth_resize_window_ = nullptr;
+  auto iter = overview_window_item_bounds_map_.find(window);
+  if (iter != overview_window_item_bounds_map_.end())
+    overview_window_item_bounds_map_.erase(iter);
   OnSnappedWindowMinimizedOrDestroyed(window);
 }
 
@@ -555,12 +563,28 @@ void SplitViewController::OnWindowActivated(ActivationReason reason,
     return;
   }
 
+  // If the to-be-snapped window comes from the overview grid, get its overview
+  // window item bounds before trying to snap it.
+  gfx::Rect window_item_bounds;
+  if (Shell::Get()->window_selector_controller()->IsSelecting()) {
+    WindowSelector* window_selector =
+        Shell::Get()->window_selector_controller()->window_selector();
+    WindowGrid* current_grid = window_selector->GetGridWithRootWindow(
+        GetDefaultSnappedWindow()->GetRootWindow());
+    if (current_grid) {
+      WindowSelectorItem* item =
+          current_grid->GetWindowSelectorItemContaining(gained_active);
+      if (item) {
+        window_item_bounds = item->target_bounds();
+        window_selector->RemoveWindowSelectorItem(item);
+      }
+    }
+  }
+
   // Snap the window on the non-default side of the screen if split view mode
   // is active.
-  if (default_snap_position_ == LEFT)
-    SnapWindow(gained_active, SplitViewController::RIGHT);
-  else if (default_snap_position_ == RIGHT)
-    SnapWindow(gained_active, SplitViewController::LEFT);
+  SnapWindow(gained_active, (default_snap_position_ == LEFT) ? RIGHT : LEFT,
+             window_item_bounds);
 }
 
 void SplitViewController::OnOverviewModeStarting() {
@@ -602,11 +626,10 @@ void SplitViewController::OnOverviewModeEnding() {
     for (const auto& window_selector_item : windows) {
       aura::Window* window = window_selector_item->GetWindow();
       if (CanSnap(window) && window != GetDefaultSnappedWindow()) {
+        const gfx::Rect item_bounds = window_selector_item->target_bounds();
         window_selector->RemoveWindowSelectorItem(window_selector_item.get());
-        if (default_snap_position_ == LEFT)
-          SnapWindow(window, SplitViewController::RIGHT);
-        else if (default_snap_position_ == RIGHT)
-          SnapWindow(window, SplitViewController::LEFT);
+        SnapWindow(window, (default_snap_position_ == LEFT) ? RIGHT : LEFT,
+                   item_bounds);
         return;
       }
     }
@@ -1136,14 +1159,30 @@ void SplitViewController::RestoreAndActivateSnappedWindow(
     aura::Window* window) {
   DCHECK(window == left_window_ || window == right_window_);
 
-  // Restore the window's transform first if its transform is not identity. In
-  // this case the window must come from the overview window grid.
+  // If the snapped window comes from the overview window grid, calculate a good
+  // starting transform based on the overview window item's bounds.
+  gfx::Transform starting_transform;
+  auto iter = overview_window_item_bounds_map_.find(window);
+  if (iter != overview_window_item_bounds_map_.end()) {
+    const gfx::Rect item_bounds = iter->second;
+    overview_window_item_bounds_map_.erase(iter);
+
+    // Calculate the starting transform based on the window's expected snapped
+    // bounds and its window item bounds in overview.
+    const gfx::Rect snapped_bounds = GetSnappedWindowBoundsInScreen(
+        window, (window == left_window_) ? LEFT : RIGHT);
+    starting_transform = ScopedTransformOverviewWindow::GetTransformForRect(
+        snapped_bounds, item_bounds);
+  }
+
+  // Restore the window's transform first if it's not identity.
   if (!window->layer()->GetTargetTransform().IsIdentity()) {
     for (auto* window_iter : wm::GetTransientTreeIterator(window)) {
-      ScopedOverviewAnimationSettings animation_settings(
-          ash::OverviewAnimationType::OVERVIEW_ANIMATION_RESTORE_WINDOW,
-          window_iter);
-      window_iter->SetTransform(gfx::Transform());
+      if (!starting_transform.IsIdentity())
+        window_iter->SetTransform(starting_transform);
+      DoSplitviewTransformAnimation(window_iter->layer(),
+                                    SPLITVIEW_ANIMATION_RESTORE_OVERVIEW_WINDOW,
+                                    gfx::Transform(), nullptr);
     }
   }
   wm::ActivateWindow(window);

ash/wm/splitview/split_view_controller.h

@@ -11,6 +11,7 @@
 #include "ash/shell_observer.h"
 #include "ash/wm/tablet_mode/tablet_mode_observer.h"
 #include "ash/wm/window_state_observer.h"
+#include "base/containers/flat_map.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "base/time/time.h"
@@ -90,8 +91,12 @@ class ASH_EXPORT SplitViewController : public mojom::SplitViewController,
   // primary orientation.
   bool IsCurrentScreenOrientationPrimary() const;
 
-  // Snaps window to left/right.
-  void SnapWindow(aura::Window* window, SnapPosition snap_position);
+  // Snaps window to left/right. |window_item_bounds| is the bounds of the
+  // overview window item in overview. It's empty if the snapped window doesn't
+  // come from overview grid.
+  void SnapWindow(aura::Window* window,
+                  SnapPosition snap_position,
+                  const gfx::Rect& window_item_bounds = gfx::Rect());
 
   // Swaps the left and right windows. This will do nothing if one of the
   // windows is not snapped.
@@ -350,6 +355,10 @@ class ASH_EXPORT SplitViewController : public mojom::SplitViewController,
   // details.
   aura::Window* smooth_resize_window_ = nullptr;
 
+  // The map from a to-be-snapped window to its overview item's bounds if the
+  // window comes from the overview.
+  base::flat_map<aura::Window*, gfx::Rect> overview_window_item_bounds_map_;
+
   base::ObserverList<Observer> observers_;
   mojo::InterfacePtrSet<mojom::SplitViewObserver> mojo_observers_;
 

ash/wm/splitview/split_view_utils.cc

@@ -29,15 +29,21 @@ constexpr base::TimeDelta kLabelAnimationMs =
 // The delay before the indicator labels start animating.
 constexpr base::TimeDelta kLabelAnimationDelayMs =
     base::TimeDelta::FromMilliseconds(167);
+// The time duration for the window transformation animations.
+constexpr base::TimeDelta kWindowTransformMs =
+    base::TimeDelta::FromMilliseconds(300);
 
 constexpr float kHighlightOpacity = 0.3f;
 constexpr float kPreviewAreaHighlightOpacity = 0.18f;
 
 // Gets the duration, tween type and delay before animation based on |type|.
-void GetAnimationValuesForType(SplitviewAnimationType type,
+void GetAnimationValuesForType(
+    SplitviewAnimationType type,
     base::TimeDelta* out_duration,
     gfx::Tween::Type* out_tween_type,
+    ui::LayerAnimator::PreemptionStrategy* out_preemption_strategy,
     base::TimeDelta* out_delay) {
+  *out_preemption_strategy = ui::LayerAnimator::IMMEDIATELY_SET_NEW_TARGET;
   switch (type) {
     case SPLITVIEW_ANIMATION_HIGHLIGHT_FADE_IN:
     case SPLITVIEW_ANIMATION_HIGHLIGHT_FADE_OUT:
@@ -71,20 +77,29 @@ void GetAnimationValuesForType(SplitviewAnimationType type,
       *out_duration = kOtherFadeInOutMs;
       *out_tween_type = gfx::Tween::LINEAR_OUT_SLOW_IN;
       return;
+    case SPLITVIEW_ANIMATION_RESTORE_OVERVIEW_WINDOW:
+      *out_duration = kWindowTransformMs;
+      *out_tween_type = gfx::Tween::EASE_OUT;
+      *out_preemption_strategy =
+          ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET;
+      return;
   }
 
   NOTREACHED();
 }
 
 // Helper function to apply animation values to |settings|.
-void ApplyAnimationSettings(ui::ScopedLayerAnimationSettings* settings,
+void ApplyAnimationSettings(
+    ui::ScopedLayerAnimationSettings* settings,
     ui::LayerAnimator* animator,
     base::TimeDelta duration,
     gfx::Tween::Type tween,
+    ui::LayerAnimator::PreemptionStrategy preemption_strategy,
     base::TimeDelta delay) {
   DCHECK_EQ(settings->GetAnimator(), animator);
   settings->SetTransitionDuration(duration);
   settings->SetTweenType(tween);
+  settings->SetPreemptionStrategy(preemption_strategy);
   if (!delay.is_zero()) {
     settings->SetPreemptionStrategy(
         ui::LayerAnimator::REPLACE_QUEUED_ANIMATIONS);
@@ -130,12 +145,15 @@ void DoSplitviewOpacityAnimation(ui::Layer* layer,
 
   base::TimeDelta duration;
   gfx::Tween::Type tween;
+  ui::LayerAnimator::PreemptionStrategy preemption_strategy;
   base::TimeDelta delay;
-  GetAnimationValuesForType(type, &duration, &tween, &delay);
+  GetAnimationValuesForType(type, &duration, &tween, &preemption_strategy,
+                            &delay);
 
   ui::LayerAnimator* animator = layer->GetAnimator();
   ui::ScopedLayerAnimationSettings settings(animator);
-  ApplyAnimationSettings(&settings, animator, duration, tween, delay);
+  ApplyAnimationSettings(&settings, animator, duration, tween,
+                         preemption_strategy, delay);
   layer->SetOpacity(target_opacity);
 }
 
@@ -150,6 +168,7 @@ void DoSplitviewTransformAnimation(ui::Layer* layer,
     case SPLITVIEW_ANIMATION_OTHER_HIGHLIGHT_SLIDE_IN:
     case SPLITVIEW_ANIMATION_OTHER_HIGHLIGHT_SLIDE_OUT:
     case SPLITVIEW_ANIMATION_PREVIEW_AREA_SLIDE_IN_OUT:
+    case SPLITVIEW_ANIMATION_RESTORE_OVERVIEW_WINDOW:
     case SPLITVIEW_ANIMATION_TEXT_SLIDE_IN:
     case SPLITVIEW_ANIMATION_TEXT_SLIDE_OUT:
       break;
@@ -160,12 +179,15 @@ void DoSplitviewTransformAnimation(ui::Layer* layer,
 
   base::TimeDelta duration;
   gfx::Tween::Type tween;
+  ui::LayerAnimator::PreemptionStrategy preemption_strategy;
   base::TimeDelta delay;
-  GetAnimationValuesForType(type, &duration, &tween, &delay);
+  GetAnimationValuesForType(type, &duration, &tween, &preemption_strategy,
+                            &delay);
 
   ui::LayerAnimator* animator = layer->GetAnimator();
   ui::ScopedLayerAnimationSettings settings(animator);
-  ApplyAnimationSettings(&settings, animator, duration, tween, delay);
+  ApplyAnimationSettings(&settings, animator, duration, tween,
+                         preemption_strategy, delay);
   if (observer)
     settings.AddObserver(observer);
   layer->SetTransform(target_transform);

ash/wm/splitview/split_view_utils.h

@@ -55,6 +55,8 @@ enum SplitviewAnimationType {
   // Used to slide in the text labels.
   SPLITVIEW_ANIMATION_TEXT_SLIDE_IN,
   SPLITVIEW_ANIMATION_TEXT_SLIDE_OUT,
+  // Used to apply window transform on the selector item after it gets snapped.
+  SPLITVIEW_ANIMATION_RESTORE_OVERVIEW_WINDOW,
 };
 
 // Animates |layer|'s opacity based on |type|.