Panels: Adding 3-step animation on minimize on Linux

chrome/browser/ui/panels/panel_slide_animation.cc

+// Copyright (c) 2011 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/panels/panel_slide_animation.h"
+
+#include "chrome/browser/ui/panels/panel.h"
+
+namespace {
+// These values are experimental and subjective.
+const int kSetBoundsAnimationMs = 180;
+const int kSetBoundsAnimationMinimizeMs = 1500;
+}
+
+PanelSlideAnimation::PanelSlideAnimation(ui::AnimationDelegate* target,
+                                         Panel* panel,
+                                         gfx::Rect initial_bounds,
+                                         gfx::Rect final_bounds)
+  : ui::SlideAnimation(target),

[jianli, 2011/12/06 19:55:10]

nit: 4 spaces for indenting.

[Dmitry Titov, 2011/12/07 03:46:04]

Done.

+    panel_(panel),
+    for_minimize_(false),
+    animation_stop_to_show_titlebar_(0) {
+  // Detect animation that happens when expansion state is set to MINIMIZED
+  // and there is relatively big portion of the panel to hide from view.
+  // Initialize animation differently in this case, using fast-pause-slow
+  // method, see below for more details.
+  int duration = kSetBoundsAnimationMs;
+  if (panel_->expansion_state() == Panel::MINIMIZED) {
+    double hidden_title_height =
+        panel_->TitleOnlyHeight() - final_bounds.height();
+    double distance_y = initial_bounds.height() - final_bounds.height();
+    animation_stop_to_show_titlebar_ = 1.0 - hidden_title_height / distance_y;
+    if (animation_stop_to_show_titlebar_ > 0.7) {  // Relatively big movement.
+      for_minimize_ = true;
+      duration = kSetBoundsAnimationMinimizeMs;
+    }
+  }
+  SetSlideDuration(duration);
+}
+
+PanelSlideAnimation::~PanelSlideAnimation() { }

[jianli, 2011/12/06 19:55:10]

nit: better to put into 2 lines.

[Dmitry Titov, 2011/12/07 03:46:04]

Done.

+
+double PanelSlideAnimation::GetCurrentValue() const {

[jianli, 2011/12/06 19:55:10]

It might be better to change this to a helper function so that it can also be
used by Mac. Maybe a static public method defined in PanelSlideAnimation, like:
  static double GetValueFromProgress(double progress, double
animation_stop_to_show_titlebar, bool for_minimize);

[Dmitry Titov, 2011/12/07 03:46:04]

Done.

+  double progress = ui::SlideAnimation::GetCurrentValue();
+  if (!for_minimize_) {
+    // Cubic easing out.
+    float value = 1.0 - progress;
+    return 1.0 - value * value * value;
+  }
+
+  // Minimize animation:
+  // 1. Quickly (0 -> 0.15) make only titlebar visible.
+  // 2. Stay a little bit (0.15->0.6) in place, just showing titlebar.
+  // 3. Slowly minimize to thin strip (0.6->1.0)
+  const double kAnimationStopAfterQuickDecrease = 0.15;
+  const double kAnimationStopAfterShowingTitlebar = 0.6;
+  double value;
+  if (progress <= kAnimationStopAfterQuickDecrease) {
+      value = progress * animation_stop_to_show_titlebar_ /

[jianli, 2011/12/06 19:55:10]

nit: indenting

[Dmitry Titov, 2011/12/07 03:46:04]

Done.

+          kAnimationStopAfterQuickDecrease;
+  } else if (progress <= kAnimationStopAfterShowingTitlebar) {
+      value = animation_stop_to_show_titlebar_;
+  } else {
+      value = animation_stop_to_show_titlebar_ +
+          (progress - kAnimationStopAfterShowingTitlebar) *
+          (1.0 - animation_stop_to_show_titlebar_) /
+          (1.0 - kAnimationStopAfterShowingTitlebar);
+  }
+  return value;
+}
+