1 files changed, 114 insertions, 0 deletions
diff --git a/ui/base/animation/slide_animation.cc b/ui/base/animation/slide_animation.cc
new file mode 100644
index 0000000..ec08334
--- /dev/null
+++ b/ui/base/animation/slide_animation.cc
@@ -0,0 +1,114 @@
+// 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 "ui/base/animation/slide_animation.h"
+
+#include <math.h>
+
+namespace ui {
+
+// How many frames per second to target.
+static const int kDefaultFramerateHz = 50;
+
+// How long animations should take by default.
+static const int kDefaultDurationMs = 120;
+
+SlideAnimation::SlideAnimation(AnimationDelegate* target)
+    : LinearAnimation(kDefaultFramerateHz, target),
+      target_(target),
+      tween_type_(Tween::EASE_OUT),
+      showing_(false),
+      value_start_(0),
+      value_end_(0),
+      value_current_(0),
+      slide_duration_(kDefaultDurationMs) {
+}
+
+SlideAnimation::~SlideAnimation() {
+}
+
+void SlideAnimation::Reset() {
+  Reset(0);
+}
+
+void SlideAnimation::Reset(double value) {
+  Stop();
+  showing_ = static_cast<bool>(value == 1);
+  value_current_ = value;
+}
+
+void SlideAnimation::Show() {
+  // If we're already showing (or fully shown), we have nothing to do.
+  if (showing_)
+    return;
+
+  showing_ = true;
+  value_start_ = value_current_;
+  value_end_ = 1.0;
+
+  // Make sure we actually have something to do.
+  if (slide_duration_ == 0) {
+    AnimateToState(1.0);  // Skip to the end of the animation.
+    return;
+  } else if (value_current_ == value_end_)  {
+    return;
+  }
+
+  // This will also reset the currently-occuring animation.
+  SetDuration(static_cast<int>(slide_duration_ * (1 - value_current_)));
+  Start();
+}
+
+void SlideAnimation::Hide() {
+  // If we're already hiding (or hidden), we have nothing to do.
+  if (!showing_)
+    return;
+
+  showing_ = false;
+  value_start_ = value_current_;
+  value_end_ = 0.0;
+
+  // Make sure we actually have something to do.
+  if (slide_duration_ == 0) {
+    AnimateToState(0.0);  // Skip to the end of the animation.
+    return;
+  } else if (value_current_ == value_end_) {
+    return;
+  }
+
+  // This will also reset the currently-occuring animation.
+  SetDuration(static_cast<int>(slide_duration_ * value_current_));
+  Start();
+}
+
+void SlideAnimation::SetSlideDuration(int duration) {
+  slide_duration_ = duration;
+}
+
+double SlideAnimation::GetCurrentValue() const {
+  return value_current_;
+}
+
+void SlideAnimation::AnimateToState(double state) {
+  if (state > 1.0)
+    state = 1.0;
+
+  state = Tween::CalculateValue(tween_type_, state);
+
+  value_current_ = value_start_ + (value_end_ - value_start_) * state;
+
+  // Implement snapping.
+  if (tween_type_ == Tween::EASE_OUT_SNAP &&
+      fabs(value_current_ - value_end_) <= 0.06)
+    value_current_ = value_end_;
+
+  // Correct for any overshoot (while state may be capped at 1.0, let's not
+  // take any rounding error chances.
+  if ((value_end_ >= value_start_ && value_current_ > value_end_) ||
+      (value_end_ < value_start_ && value_current_ < value_end_)) {
+    value_current_ = value_end_;
+  }
+}
+
+}  // namespace ui