Implemented screen rotation animation experiment.

ash/rotator/screen_rotation.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 "ash/rotator/screen_rotation.h"
-
-#include "base/time/time.h"
-#include "ui/compositor/layer.h"
-#include "ui/gfx/geometry/rect.h"
-#include "ui/gfx/interpolated_transform.h"
-#include "ui/gfx/transform.h"
-
-namespace ash {
-
-namespace {
-
-const int k90DegreeTransitionDurationMs = 350;
-const int k180DegreeTransitionDurationMs = 550;
-const int k360DegreeTransitionDurationMs = 750;
-
-base::TimeDelta GetTransitionDuration(int degrees) {
-  if (degrees == 360)
-    return base::TimeDelta::FromMilliseconds(k360DegreeTransitionDurationMs);
-  if (degrees == 180)
-    return base::TimeDelta::FromMilliseconds(k180DegreeTransitionDurationMs);
-  if (degrees == 0)
-    return base::TimeDelta::FromMilliseconds(0);
-  return base::TimeDelta::FromMilliseconds(k90DegreeTransitionDurationMs);
-}
-
-}  // namespace
-
-ScreenRotation::ScreenRotation(int degrees, ui::Layer* layer)
-    : ui::LayerAnimationElement(LayerAnimationElement::TRANSFORM,
-                                GetTransitionDuration(degrees)),
-      degrees_(degrees) {
-  InitTransform(layer);
-}
-
-ScreenRotation::~ScreenRotation() {
-}
-
-void ScreenRotation::InitTransform(ui::Layer* layer) {
-  // No rotation required, use the identity transform.
-  if (degrees_ == 0) {
-    interpolated_transform_.reset(
-        new ui::InterpolatedConstantTransform(gfx::Transform()));
-    return;
-  }
-
-  // Use the target transform/bounds in case the layer is already animating.
-  const gfx::Transform& current_transform = layer->GetTargetTransform();
-  const gfx::Rect& bounds = layer->GetTargetBounds();
-
-  gfx::Point old_pivot;
-  gfx::Point new_pivot;
-
-  int width = bounds.width();
-  int height = bounds.height();
-
-  switch (degrees_) {
-    case 90:
-      new_origin_ = new_pivot = gfx::Point(width, 0);
-      break;
-    case -90:
-      new_origin_ = new_pivot = gfx::Point(0, height);
-      break;
-    case 180:
-    case 360:
-      new_pivot = old_pivot = gfx::Point(width / 2, height / 2);
-      new_origin_.SetPoint(width, height);
-      break;
-  }
-
-  // Convert points to world space.
-  current_transform.TransformPoint(&old_pivot);
-  current_transform.TransformPoint(&new_pivot);
-  current_transform.TransformPoint(&new_origin_);
-
-  scoped_ptr<ui::InterpolatedTransform> rotation(
-      new ui::InterpolatedTransformAboutPivot(
-          old_pivot,
-          new ui::InterpolatedRotation(0, degrees_)));
-
-  scoped_ptr<ui::InterpolatedTransform> translation(
-      new ui::InterpolatedTranslation(
-          gfx::Point(0, 0),
-          gfx::Point(new_pivot.x() - old_pivot.x(),
-                     new_pivot.y() - old_pivot.y())));
-
-  float scale_factor = 0.9f;
-  scoped_ptr<ui::InterpolatedTransform> scale_down(
-      new ui::InterpolatedScale(1.0f, scale_factor, 0.0f, 0.5f));
-
-  scoped_ptr<ui::InterpolatedTransform> scale_up(
-      new ui::InterpolatedScale(1.0f, 1.0f / scale_factor, 0.5f, 1.0f));
-
-  interpolated_transform_.reset(
-      new ui::InterpolatedConstantTransform(current_transform));
-
-  scale_up->SetChild(scale_down.release());
-  translation->SetChild(scale_up.release());
-  rotation->SetChild(translation.release());
-  interpolated_transform_->SetChild(rotation.release());
-}
-
-void ScreenRotation::OnStart(ui::LayerAnimationDelegate* delegate) {
-}
-
-bool ScreenRotation::OnProgress(double t,
-                                ui::LayerAnimationDelegate* delegate) {
-  delegate->SetTransformFromAnimation(interpolated_transform_->Interpolate(t));
-  return true;
-}
-
-void ScreenRotation::OnGetTarget(TargetValue* target) const {
-  target->transform = interpolated_transform_->Interpolate(1.0);
-}
-
-void ScreenRotation::OnAbort(ui::LayerAnimationDelegate* delegate) {
-}
-
-}  // namespace ash