An energy usage monitor for Mac, and some layer-backed throbber experiments

chrome/browser/ui/views/tabs/tab.cc

 // 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.
 
 #include "chrome/browser/ui/views/tabs/tab.h"
 
 #include <limits>
 
 #include "base/command_line.h"
 #include "base/debug/alias.h"
@@ skipping 12 matching lines @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/grit/generated_resources.h"
 #include "content/public/browser/user_metrics.h"
 #include "grit/theme_resources.h"
 #include "third_party/skia/include/effects/SkGradientShader.h"
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/models/list_selection_model.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/theme_provider.h"
+#include "ui/compositor/layer_animator.h"
+#include "ui/compositor/paint_recorder.h"
 #include "ui/gfx/animation/animation_container.h"
 #include "ui/gfx/animation/multi_animation.h"
 #include "ui/gfx/animation/throb_animation.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/color_analysis.h"
 #include "ui/gfx/favicon_size.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/image/image_skia_operations.h"
 #include "ui/gfx/paint_vector_icon.h"
 #include "ui/gfx/path.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/gfx/vector_icons_public.h"
 #include "ui/resources/grit/ui_resources.h"
 #include "ui/views/border.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/rect_based_targeting_utils.h"
 #include "ui/views/view_targeter.h"
 #include "ui/views/widget/tooltip_manager.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/window/non_client_view.h"
 
 #if defined(USE_AURA)
 #include "ui/aura/env.h"
 #endif
 
+#include "base/debug/stack_trace.h"
+
 using base::UserMetricsAction;
 
 namespace {
 
 // Height of the shadow at the top of the tab image assets.
 const int kDropShadowHeight = 4;
 
 // How long the pulse throb takes.
 const int kPulseDurationMs = 200;
 
@@ skipping 316 matching lines @@
 // ImageCacheEntry
 
 Tab::ImageCacheEntry::ImageCacheEntry()
     : resource_id(-1),
       scale_factor(ui::SCALE_FACTOR_NONE) {
 }
 
 Tab::ImageCacheEntry::~ImageCacheEntry() {}
 
 ////////////////////////////////////////////////////////////////////////////////
+// ThrobberView
+
+class Tab::ThrobberView : public views::View {
+ public:
+  ThrobberView(Tab* owner, const gfx::Rect& bounds)
+      : owner_(owner),
+        waiting_arc_(owner_->GetThemeProvider()->GetColor(
+                         ThemeProperties::COLOR_THROBBER_WAITING),
+                     180) {
+    SetPaintToLayer(true);
+    SetFillsBoundsOpaquely(false);
+    SetBoundsRect(bounds);
+    owner_->AddChildView(this);
+
+    mask_.SetFillsBoundsOpaquely(false);
+    mask_.SetMasksToBounds(true);
+  }
+
+  void SchedulePaintIfRequired() {
+    if (NeedsPaint())
+      SchedulePaint();
+  }
+
+  // views::View:
+  void OnBoundsChanged(const gfx::Rect& previous_bounds) override {
+    gfx::Rect bounds = GetLocalBounds();
+    waiting_arc_.layer()->SetBounds(
+        gfx::Rect(0, 0, bounds.width() * Arc::kAA, bounds.height() * Arc::kAA));
+
+    bounds.set_width(bounds.width() / 2);
+    mask_.SetBounds(bounds);
+  }
+
+  void OnPaint(gfx::Canvas* canvas) override {
+    state_ = owner_->data().network_state;
+    if (state_ == TabRendererData::NETWORK_STATE_NONE)
+      return;
+
+    const gfx::Rect bounds = GetLocalBounds();
+
+    // Paint network activity (aka throbber) animation frame.
+    ui::ThemeProvider* tp = owner_->GetThemeProvider();
+    if (state_ == TabRendererData::NETWORK_STATE_WAITING) {
+      // Painted by Arc.
+    } else {
+      if (loading_start_time_ == base::TimeTicks())
+        loading_start_time_ = base::TimeTicks::Now();
+
+      waiting_state_.color =
+          tp->GetColor(ThemeProperties::COLOR_THROBBER_WAITING);
+      gfx::PaintThrobberSpinningAfterWaiting(
+          canvas, bounds,
+          tp->GetColor(ThemeProperties::COLOR_THROBBER_SPINNING),
+          base::TimeTicks::Now() - loading_start_time_, &waiting_state_);
+    }
+  }
+
+ private:
+  class Arc : public ui::LayerDelegate {
+   public:
+    // Since the rotation transform mis-aligns the pixel anti-aliasing done by
+    // Skia, perform a kind of FSAA by drawing on a larger canvas and scaling
+    // down as part of the transform.
+    static const int kAA = 4;
+
+    Arc(SkColor color, SkScalar sweep)
+        : color_(color), sweep_(sweep), layer_(ui::LAYER_TEXTURED) {
+      layer_.set_delegate(this);
+      layer_.SetFillsBoundsOpaquely(false);
+    }
+
+    ui::Layer* layer() { return &layer_; }
+
+    void SetAngle(SkScalar angle) {
+      const gfx::Size size = layer()->size();
+      gfx::Transform transform;
+      transform.Translate(size.width() / 2.0 / kAA, size.height() / 2.0 / kAA);
+      transform.Rotate(-angle);
+      transform.Scale(1.0 / kAA, 1.0 / kAA);
+      transform.Translate(-size.width() / 2, -size.height() / 2);
+      layer()->SetTransform(transform);
+    }
+
+    // LayerDelegate:
+    void OnPaintLayer(const ui::PaintContext& context) override {
+      const gfx::Size size = layer()->size();
+      ui::PaintRecorder recorder(context, size);
+      gfx::PaintThrobberArc(recorder.canvas(), gfx::Rect(size), color_, -90,
+                            sweep_);
+    }
+
+    void OnDelegatedFrameDamage(const gfx::Rect& damage_rect_in_dip) override {}
+    void OnDeviceScaleFactorChanged(float device_scale_factor) override {}
+    base::Closure PrepareForLayerBoundsChange() override {
+      return base::Closure();
+    }
+
+   private:
+    SkColor color_;
+    SkScalar sweep_;
+    ui::Layer layer_;
+
+    DISALLOW_COPY_AND_ASSIGN(Arc);
+  };
+
+  void ApplyWaitingRotation(const base::TimeDelta& elapsed_time) {
+    const base::TimeDelta revolution_time =
+        base::TimeDelta::FromMilliseconds(1320);
+    bool needs_mask = elapsed_time < revolution_time / 2;
+    mask_.SetMasksToBounds(needs_mask);
+    waiting_arc_.SetAngle(360 * waiting_state_.elapsed_time / revolution_time);
+  }
+
+  bool NeedsPaint() {
+    if (bounds().IsEmpty())
+      return false;
+
+    TabRendererData::NetworkState new_state = owner_->data().network_state;
+    const bool changing_state = new_state != state_;
+
+    // Waiting throbber is fully layer-backed.
+    if (new_state == TabRendererData::NETWORK_STATE_WAITING) {
+      if (waiting_start_time_ == base::TimeTicks())
+        waiting_start_time_ = base::TimeTicks::Now();
+
+      state_ = new_state;
+      waiting_state_.elapsed_time =
+          base::TimeTicks::Now() - waiting_start_time_;
+      layer()->Add(&mask_);
+      mask_.Add(waiting_arc_.layer());
+      ApplyWaitingRotation(waiting_state_.elapsed_time);
+      return changing_state;
+    }
+
+    return true;
+  }
+
+  Tab* owner_;  // Weak. Owns this.
+
+  TabRendererData::NetworkState state_ = TabRendererData::NETWORK_STATE_NONE;
+
+  // The point in time when the tab icon was first painted in the waiting state.
+  base::TimeTicks waiting_start_time_;
+
+  // The point in time when the tab icon was first painted in the loading state.
+  base::TimeTicks loading_start_time_;
+
+  // Paint state for the throbber after the most recent waiting paint.
+  gfx::ThrobberWaitingState waiting_state_;
+
+  ui::Layer mask_;
+  Arc waiting_arc_;
+
+  DISALLOW_COPY_AND_ASSIGN(ThrobberView);
+};
+
+////////////////////////////////////////////////////////////////////////////////
 // Tab, statics:
 
 // static
 const char Tab::kViewClassName[] = "Tab";
 Tab::TabImage Tab::tab_active_ = {0};
 Tab::TabImage Tab::tab_inactive_ = {0};
 Tab::TabImage Tab::tab_alpha_ = {0};
 Tab::ImageCache* Tab::image_cache_ = NULL;
 
 ////////////////////////////////////////////////////////////////////////////////
 // Tab, public:
 
 Tab::Tab(TabController* controller)
     : controller_(controller),
       closing_(false),
       dragging_(false),
       detached_(false),
       favicon_hiding_offset_(0),
       immersive_loading_step_(0),
       should_display_crashed_favicon_(false),
+      throbber_(nullptr),
       media_indicator_button_(nullptr),
       close_button_(nullptr),
       title_(new views::Label()),
       tab_activated_with_last_tap_down_(false),
       hover_controller_(this),
       showing_icon_(false),
       showing_media_indicator_(false),
       showing_close_button_(false),
       button_color_(SK_ColorTRANSPARENT) {
   DCHECK(controller);
@@ skipping 120 matching lines @@
 }
 
 void Tab::UpdateLoadingAnimation(TabRendererData::NetworkState state) {
   if (state == data_.network_state &&
       state == TabRendererData::NETWORK_STATE_NONE) {
     // If the network state is none and hasn't changed, do nothing. Otherwise we
     // need to advance the animation frame.
     return;
   }
 
-  TabRendererData::NetworkState old_state = data_.network_state;
   data_.network_state = state;
-  AdvanceLoadingAnimation(old_state, state);
+  AdvanceLoadingAnimation(state);
 }
 
 void Tab::StartPulse() {
   pulse_animation_.reset(new gfx::ThrobAnimation(this));
   pulse_animation_->SetSlideDuration(kPulseDurationMs);
   if (animation_container_.get())
     pulse_animation_->SetContainer(animation_container_.get());
   pulse_animation_->StartThrobbing(std::numeric_limits<int>::max());
 }
 
@@ skipping 212 matching lines @@
   const int extra_padding =
       (controller_->ShouldHideCloseButtonForInactiveTabs() ||
        (IconCapacity() < 3)) ? 0 : kExtraLeftPaddingToBalanceCloseButtonPadding;
   const int start = lb.x() + extra_padding;
   favicon_bounds_.SetRect(start, lb.y(), 0, 0);
   if (showing_icon_) {
     favicon_bounds_.set_size(gfx::Size(gfx::kFaviconSize, gfx::kFaviconSize));
     favicon_bounds_.set_y(lb.y() + (lb.height() - gfx::kFaviconSize + 1) / 2);
     MaybeAdjustLeftForPinnedTab(&favicon_bounds_);
   }
+  if (throbber_)
+    throbber_->SetBoundsRect(favicon_bounds_);
 
   showing_close_button_ = ShouldShowCloseBox();
   if (showing_close_button_) {
     // If the ratio of the close button size to tab width exceeds the maximum.
     // The close button should be as large as possible so that there is a larger
     // hit-target for touch events. So the close button bounds extends to the
     // edges of the tab. However, the larger hit-target should be active only
     // for mouse events, and the close-image should show up in the right place.
     // So a border is added to the button with necessary padding. The close
     // button (BaseTab::TabCloseButton) makes sure the padding is a hit-target
@@ skipping 540 matching lines @@
 }
 
 void Tab::PaintIcon(gfx::Canvas* canvas) {
   gfx::Rect bounds = favicon_bounds_;
   if (bounds.IsEmpty())
     return;
 
   bounds.set_x(GetMirroredXForRect(bounds));
 
   if (data().network_state != TabRendererData::NETWORK_STATE_NONE) {
-    // Paint network activity (aka throbber) animation frame.
-    ui::ThemeProvider* tp = GetThemeProvider();
-    if (data().network_state == TabRendererData::NETWORK_STATE_WAITING) {
-      if (waiting_start_time_ == base::TimeTicks())
-        waiting_start_time_ = base::TimeTicks::Now();
-
-      waiting_state_.elapsed_time =
-          base::TimeTicks::Now() - waiting_start_time_;
-      gfx::PaintThrobberWaiting(
-          canvas, bounds, tp->GetColor(ThemeProperties::COLOR_THROBBER_WAITING),
-          waiting_state_.elapsed_time);
-    } else {
-      if (loading_start_time_ == base::TimeTicks())
-        loading_start_time_ = base::TimeTicks::Now();
-
-      waiting_state_.color =
-          tp->GetColor(ThemeProperties::COLOR_THROBBER_WAITING);
-      gfx::PaintThrobberSpinningAfterWaiting(
-          canvas, bounds,
-          tp->GetColor(ThemeProperties::COLOR_THROBBER_SPINNING),
-          base::TimeTicks::Now() - loading_start_time_, &waiting_state_);
-    }
+    // Throbber will do its own painting.
   } else if (should_display_crashed_favicon_) {
     // Paint crash favicon.
     ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
     gfx::ImageSkia crashed_favicon(*rb.GetImageSkiaNamed(IDR_SAD_FAVICON));
     bounds.set_y(bounds.y() + favicon_hiding_offset_);
     DrawIconCenter(canvas, crashed_favicon, 0,
                    crashed_favicon.width(),
                    crashed_favicon.height(),
                    bounds, true, SkPaint());
   } else if (!data().favicon.isNull()) {
     // Paint the normal favicon.
     DrawIconCenter(canvas, data().favicon, 0,
                    data().favicon.width(),
                    data().favicon.height(),
                    bounds, true, SkPaint());
   }
 }
 
-void Tab::AdvanceLoadingAnimation(TabRendererData::NetworkState old_state,
-                                  TabRendererData::NetworkState state) {
+void Tab::AdvanceLoadingAnimation(TabRendererData::NetworkState state) {
   if (state == TabRendererData::NETWORK_STATE_WAITING) {
     // Waiting steps backwards.
     immersive_loading_step_ =
         (immersive_loading_step_ - 1 + kImmersiveLoadingStepCount) %
             kImmersiveLoadingStepCount;
   } else if (state == TabRendererData::NETWORK_STATE_LOADING) {
     immersive_loading_step_ = (immersive_loading_step_ + 1) %
         kImmersiveLoadingStepCount;
   } else {
-    waiting_start_time_ = base::TimeTicks();
-    loading_start_time_ = base::TimeTicks();
-    waiting_state_ = gfx::ThrobberWaitingState();
     immersive_loading_step_ = 0;
   }
+
   if (controller_->IsImmersiveStyle()) {
     SchedulePaintInRect(GetImmersiveBarRect());
-  } else {
+    return;
+  }
+
+  const bool needs_throbber = state != TabRendererData::NETWORK_STATE_NONE;
+  if (needs_throbber && !throbber_) {
+    throbber_ = new ThrobberView(this, favicon_bounds_);
+    ScheduleIconPaint();  // Repaint the icon area to not show the icon.
+  } else if (!needs_throbber) {
+    delete throbber_;
+    throbber_ = nullptr;
     ScheduleIconPaint();
   }
+  if (throbber_)
+    throbber_->SchedulePaintIfRequired();
 }
 
 int Tab::IconCapacity() const {
   const gfx::Size min_size(GetMinimumUnselectedSize());
   if (height() < min_size.height())
     return 0;
   const int available_width = std::max(0, width() - min_size.width());
   // All icons are the same size as the favicon.
   const int icon_width = gfx::kFaviconSize;
   // We need enough space to display the icons flush against each other.
@@ skipping 258 matching lines @@
                          const gfx::ImageSkia& image) {
   DCHECK_NE(scale_factor, ui::SCALE_FACTOR_NONE);
   ImageCacheEntry entry;
   entry.resource_id = resource_id;
   entry.scale_factor = scale_factor;
   entry.image = image;
   image_cache_->push_front(entry);
   if (image_cache_->size() > kMaxImageCacheSize)
     image_cache_->pop_back();
 }