Make scroll offset type of float in cc

cc/animation/scroll_offset_animation_curve.cc

 // Copyright 2013 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 "cc/animation/scroll_offset_animation_curve.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/logging.h"
@@ skipping 26 matching lines @@
   const double r2 = 0.42 * 0.42;
   const double v2 = velocity * velocity;
   const double x1 = std::sqrt(r2 / (v2 + 1));
   const double y1 = std::sqrt(r2 * v2 / (v2 + 1));
   return CubicBezierTimingFunction::Create(x1, y1, 0.58, 1);
 }
 
 }  // namespace
 
 scoped_ptr<ScrollOffsetAnimationCurve> ScrollOffsetAnimationCurve::Create(
-    const gfx::Vector2dF& target_value,
+    const gfx::ScrollOffset& target_value,
     scoped_ptr<TimingFunction> timing_function) {
   return make_scoped_ptr(
       new ScrollOffsetAnimationCurve(target_value, timing_function.Pass()));
 }
 
 ScrollOffsetAnimationCurve::ScrollOffsetAnimationCurve(
-    const gfx::Vector2dF& target_value,
+    const gfx::ScrollOffset& target_value,
     scoped_ptr<TimingFunction> timing_function)
     : target_value_(target_value), timing_function_(timing_function.Pass()) {
 }
 
 ScrollOffsetAnimationCurve::~ScrollOffsetAnimationCurve() {}
 
 void ScrollOffsetAnimationCurve::SetInitialValue(
-    const gfx::Vector2dF& initial_value) {
+    const gfx::ScrollOffset& initial_value) {
   initial_value_ = initial_value;
-  total_animation_duration_ = DurationFromDelta(target_value_ - initial_value_);
+  total_animation_duration_ = DurationFromDelta(
+      target_value_.DeltaFrom(initial_value_));
 }
 
-gfx::Vector2dF ScrollOffsetAnimationCurve::GetValue(double t) const {
+gfx::ScrollOffset ScrollOffsetAnimationCurve::GetValue(double t) const {
   double duration = (total_animation_duration_ - last_retarget_).InSecondsF();
   t -= last_retarget_.InSecondsF();
 
   if (t <= 0)
     return initial_value_;
 
   if (t >= duration)
     return target_value_;
 
   double progress = (timing_function_->GetValue(t / duration));
-  return gfx::Vector2dF(gfx::Tween::FloatValueBetween(
-                            progress, initial_value_.x(), target_value_.x()),
-                        gfx::Tween::FloatValueBetween(
-                            progress, initial_value_.y(), target_value_.y()));
+  return gfx::ScrollOffset(
+      gfx::Tween::FloatValueBetween(
+          progress, initial_value_.x(), target_value_.x()),
+      gfx::Tween::FloatValueBetween(
+          progress, initial_value_.y(), target_value_.y()));
 }
 
 double ScrollOffsetAnimationCurve::Duration() const {
   return total_animation_duration_.InSecondsF();
 }
 
 AnimationCurve::CurveType ScrollOffsetAnimationCurve::Type() const {
   return ScrollOffset;
 }
 
 scoped_ptr<AnimationCurve> ScrollOffsetAnimationCurve::Clone() const {
   scoped_ptr<TimingFunction> timing_function(
       static_cast<TimingFunction*>(timing_function_->Clone().release()));
   scoped_ptr<ScrollOffsetAnimationCurve> curve_clone =
       Create(target_value_, timing_function.Pass());
   curve_clone->initial_value_ = initial_value_;
   curve_clone->total_animation_duration_ = total_animation_duration_;
   curve_clone->last_retarget_ = last_retarget_;
   return curve_clone.Pass();
 }
 
 void ScrollOffsetAnimationCurve::UpdateTarget(
     double t,
-    const gfx::Vector2dF& new_target) {
-  gfx::Vector2dF current_position = GetValue(t);
-  gfx::Vector2dF old_delta = target_value_ - initial_value_;
-  gfx::Vector2dF new_delta = new_target - current_position;
+    const gfx::ScrollOffset& new_target) {
+  gfx::ScrollOffset current_position = GetValue(t);
+  gfx::Vector2dF old_delta = target_value_.DeltaFrom(initial_value_);
+  gfx::Vector2dF new_delta = new_target.DeltaFrom(current_position);
 
   double old_duration =
       (total_animation_duration_ - last_retarget_).InSecondsF();
   double new_duration = DurationFromDelta(new_delta).InSecondsF();
 
   double old_velocity = timing_function_->Velocity(
       (t - last_retarget_.InSecondsF()) / old_duration);
 
   // TimingFunction::Velocity gives the slope of the curve from 0 to 1.
   // To match the "true" velocity in px/sec we must adjust this slope for
   // differences in duration and scroll delta between old and new curves.
   double new_velocity =
       old_velocity * (new_duration / old_duration) *
       (MaximumDimension(old_delta) / MaximumDimension(new_delta));
 
   initial_value_ = current_position;
   target_value_ = new_target;
   total_animation_duration_ = base::TimeDelta::FromSecondsD(t + new_duration);
   last_retarget_ = base::TimeDelta::FromSecondsD(t);
   timing_function_ = EaseOutWithInitialVelocity(new_velocity);
 }
 
 }  // namespace cc