Move Screen Rotation from MaximizeModeController to ScreenOrientationController

ash/content/display/screen_orientation_controller_chromeos.cc

Index: ash/content/display/screen_orientation_controller_chromeos.cc
diff --git a/ash/content/display/screen_orientation_controller_chromeos.cc b/ash/content/display/screen_orientation_controller_chromeos.cc
new file mode 100644
index 0000000000000000000000000000000000000000..1ed994e36ffb9464d4b418f90c0879be4fd68d93
--- /dev/null
+++ b/ash/content/display/screen_orientation_controller_chromeos.cc
@@ -0,0 +1,376 @@
+// Copyright 2014 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/content/display/screen_orientation_controller_chromeos.h"
+
+#include "ash/accelerometer/accelerometer_controller.h"
+#include "ash/ash_switches.h"
+#include "ash/display/display_info.h"
+#include "ash/display/display_manager.h"
+#include "ash/shell.h"
+#include "ash/wm/maximize_mode/maximize_mode_controller.h"
+#include "base/auto_reset.h"
+#include "base/command_line.h"
+#include "content/public/browser/screen_orientation_provider.h"
+#include "content/public/browser/web_contents.h"
+#include "ui/aura/window.h"
+#include "ui/gfx/display.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace {
+
+// The maximum deviation from the acceleration expected due to gravity under
+// which to detect hinge angle and screen rotation in m/s^2
+const float kDeviationFromGravityThreshold = 1.0f;
+
+// The angle which the screen has to be rotated past before the display will
+// rotate to match it (i.e. 45.0f is no stickiness).
+const float kDisplayRotationStickyAngleDegrees = 60.0f;
+
+// The mean acceleration due to gravity on Earth in m/s^2.
+const float kMeanGravity = 9.80665f;
+
+// The minimum acceleration in m/s^2 in a direction required to trigger screen
+// rotation. This prevents rapid toggling of rotation when the device is near
+// flat and there is very little screen aligned force on it. The value is
+// effectively the sine of the rise angle required times the acceleration due
+// to gravity, with the current value requiring at least a 25 degree rise.
+const float kMinimumAccelerationScreenRotation = 4.2f;
+
+const float kRadiansToDegrees = 180.0f / 3.14159265f;
+
+blink::WebScreenOrientationLockType GetDisplayNaturalOrientation() {
+  ash::DisplayManager* display_manager =
+      ash::Shell::GetInstance()->display_manager();
+  if (!display_manager->HasInternalDisplay())
+    return blink::WebScreenOrientationLockLandscape;
+
+  ash::DisplayInfo info =
+      display_manager->GetDisplayInfo(gfx::Display::InternalDisplayId());
+  gfx::Size size = info.size_in_pixel();
+  switch (info.rotation()) {
+    case gfx::Display::ROTATE_0:
+    case gfx::Display::ROTATE_180:
+      return size.height() >= size.width()
+                 ? blink::WebScreenOrientationLockPortrait
+                 : blink::WebScreenOrientationLockLandscape;
+    case gfx::Display::ROTATE_90:
+    case gfx::Display::ROTATE_270:
+      return size.height() < size.width()
+                 ? blink::WebScreenOrientationLockPortrait
+                 : blink::WebScreenOrientationLockLandscape;
+  }
+  NOTREACHED();
+  return blink::WebScreenOrientationLockLandscape;
+}
+
+// Returns the angle between |base| and |other| in degrees.
+float AngleBetweenVectorsInDegrees(const gfx::Vector3dF& base,
+                                   const gfx::Vector3dF& other) {
+  return acos(gfx::DotProduct(base, other) / base.Length() / other.Length()) *
+         kRadiansToDegrees;
+}
+
+// Returns the clockwise angle between |base| and |other| where |normal| is the
+// normal of the virtual surface to measure clockwise according to.
+float ClockwiseAngleBetweenVectorsInDegrees(const gfx::Vector3dF& base,
+                                            const gfx::Vector3dF& other,
+                                            const gfx::Vector3dF& normal) {
+  float angle = AngleBetweenVectorsInDegrees(base, other);
+  gfx::Vector3dF cross(base);
+  cross.Cross(other);
+
+  // If the dot product of this cross product is normal, it means that the
+  // shortest angle between |base| and |other| was counterclockwise with respect
+  // to the surface represented by |normal| and this angle must be reversed.
+  if (gfx::DotProduct(cross, normal) > 0.0f)
+    angle = 360.0f - angle;
+  return angle;
+}
+
+}  // namespace
+
+namespace ash {
+
+ScreenOrientationController::ScreenOrientationController()
+    : locking_window_(NULL),
+      natural_orientation_(GetDisplayNaturalOrientation()),
+      ignore_display_configuration_updates_(false),
+      rotation_locked_(false),
+      user_rotation_(gfx::Display::ROTATE_0),
+      current_rotation_(gfx::Display::ROTATE_0) {
+  content::ScreenOrientationProvider::SetDelegate(this);
+  Shell::GetInstance()->AddShellObserver(this);
+}
+
+ScreenOrientationController::~ScreenOrientationController() {
+  content::ScreenOrientationProvider::SetDelegate(NULL);
+  Shell::GetInstance()->RemoveShellObserver(this);
+  Shell::GetInstance()->accelerometer_controller()->RemoveObserver(this);
+  Shell::GetInstance()->display_controller()->RemoveObserver(this);
+}
+
+void ScreenOrientationController::AddObserver(Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void ScreenOrientationController::RemoveObserver(Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+void ScreenOrientationController::SetRotationLocked(bool rotation_locked) {
+  if (rotation_locked_ == rotation_locked)
+    return;
+  rotation_locked_ = rotation_locked;
+  FOR_EACH_OBSERVER(Observer, observers_,
+                    OnRotationLockChanged(rotation_locked_));
+  DisplayManager* display_manager = Shell::GetInstance()->display_manager();
+  if (!display_manager->HasInternalDisplay())
+    return;
+  base::AutoReset<bool> auto_ignore_display_configuration_updates(
+      &ignore_display_configuration_updates_, true);
+  display_manager->RegisterDisplayRotationProperties(rotation_locked_,
+                                                     current_rotation_);
+}
+
+void ScreenOrientationController::SetDisplayRotation(
+    gfx::Display::Rotation rotation) {
+  DisplayManager* display_manager = Shell::GetInstance()->display_manager();
+  if (!display_manager->HasInternalDisplay())
+    return;
+  current_rotation_ = rotation;
+  base::AutoReset<bool> auto_ignore_display_configuration_updates(
+      &ignore_display_configuration_updates_, true);
+  display_manager->SetDisplayRotation(gfx::Display::InternalDisplayId(),
+                                      rotation);
+}
+
+void ScreenOrientationController::OnAccelerometerUpdated(
+    const ui::AccelerometerUpdate& update) {
+  if (rotation_locked_)
+    return;
+  if (!update.has(ui::ACCELEROMETER_SOURCE_SCREEN))
+    return;
+  // Ignore the reading if it appears unstable. The reading is considered
+  // unstable if it deviates too much from gravity
+  if (!(std::abs(update.get(ui::ACCELEROMETER_SOURCE_SCREEN).Length() -
+                 kMeanGravity) <= kDeviationFromGravityThreshold)) {
+    return;
+  }
+  HandleScreenRotation(update.get(ui::ACCELEROMETER_SOURCE_SCREEN));
+}
+
+bool ScreenOrientationController::FullScreenRequired(
+    content::WebContents* web_contents) {
+  return true;
+}
+
+void ScreenOrientationController::Lock(
+    content::WebContents* web_contents,
+    blink::WebScreenOrientationLockType lock_orientation) {
+  aura::Window* requesting_window = web_contents->GetNativeView();
+  // TODO(jonross): Track one rotation lock per window. When the active window
+  // changes apply any corresponding rotation lock.
+  if (!locking_window_)
+    locking_window_ = requesting_window;
+  else if (requesting_window != locking_window_)
+    return;
+
+  switch (lock_orientation) {
+    case blink::WebScreenOrientationLockAny:
+      SetRotationLocked(false);
+      locking_window_ = NULL;
+      break;
+    case blink::WebScreenOrientationLockDefault:
+      NOTREACHED();
+      break;
+    case blink::WebScreenOrientationLockPortraitPrimary:
+      LockRotationToPrimaryOrientation(blink::WebScreenOrientationLockPortrait);
+      break;
+    case blink::WebScreenOrientationLockLandscape:
+    case blink::WebScreenOrientationLockPortrait:
+      LockToRotationMatchingOrientation(lock_orientation);
+      break;
+    case blink::WebScreenOrientationLockPortraitSecondary:
+      LockRotationToSecondaryOrientation(
+          blink::WebScreenOrientationLockPortrait);
+      break;
+    case blink::WebScreenOrientationLockLandscapeSecondary:
+      LockRotationToSecondaryOrientation(
+          blink::WebScreenOrientationLockLandscape);
+      break;
+    case blink::WebScreenOrientationLockLandscapePrimary:
+      LockRotationToPrimaryOrientation(
+          blink::WebScreenOrientationLockLandscape);
+      break;
+    case blink::WebScreenOrientationLockNatural:
+      LockRotation(gfx::Display::ROTATE_0);
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+}
+
+bool ScreenOrientationController::ScreenOrientationProviderSupported() {
+  return Shell::GetInstance()
+             ->maximize_mode_controller()
+             ->IsMaximizeModeWindowManagerEnabled() &&
+         CommandLine::ForCurrentProcess()->HasSwitch(
+             switches::kAshEnableTouchViewTesting);
+}
+
+void ScreenOrientationController::Unlock(content::WebContents* web_contents) {
+  aura::Window* requesting_window = web_contents->GetNativeView();
+  if (requesting_window != locking_window_)
+    return;
+  locking_window_ = NULL;
+  SetRotationLocked(false);
+}
+
+void ScreenOrientationController::OnDisplayConfigurationChanged() {
+  if (ignore_display_configuration_updates_)
+    return;
+  gfx::Display::Rotation user_rotation =
+      Shell::GetInstance()
+          ->display_manager()
+          ->GetDisplayInfo(gfx::Display::InternalDisplayId())
+          .rotation();
+  if (user_rotation != current_rotation_) {
+    // A user may change other display configuration settings. When the user
+    // does change the rotation setting, then lock rotation to prevent the
+    // accelerometer from erasing their change.
+    SetRotationLocked(true);
+    user_rotation_ = current_rotation_ = user_rotation;
+  }
+}
+
+void ScreenOrientationController::OnMaximizeModeStarted() {
+  DisplayManager* display_manager = Shell::GetInstance()->display_manager();
+  if (!display_manager->HasInternalDisplay())
+    return;
+  current_rotation_ = user_rotation_ =
+      display_manager->GetDisplayInfo(gfx::Display::InternalDisplayId())
+          .rotation();
+  LoadDisplayRotationProperties();
+  Shell::GetInstance()->accelerometer_controller()->AddObserver(this);
+  Shell::GetInstance()->display_controller()->AddObserver(this);
+}
+
+void ScreenOrientationController::OnMaximizeModeEnded() {
+  if (!Shell::GetInstance()->display_manager()->HasInternalDisplay())
+    return;
+  Shell::GetInstance()->accelerometer_controller()->RemoveObserver(this);
+  Shell::GetInstance()->display_controller()->RemoveObserver(this);
+  if (current_rotation_ != user_rotation_)
+    SetDisplayRotation(user_rotation_);
+}
+
+void ScreenOrientationController::LockRotation(
+    gfx::Display::Rotation rotation) {
+  SetRotationLocked(true);
+  SetDisplayRotation(rotation);
+}
+
+void ScreenOrientationController::LockRotationToPrimaryOrientation(
+    blink::WebScreenOrientationLockType lock_orientation) {
+  LockRotation(natural_orientation_ == lock_orientation
+                   ? gfx::Display::ROTATE_0
+                   : gfx::Display::ROTATE_90);
+}
+
+void ScreenOrientationController::LockRotationToSecondaryOrientation(
+    blink::WebScreenOrientationLockType lock_orientation) {
+  LockRotation(natural_orientation_ == lock_orientation
+                   ? gfx::Display::ROTATE_180
+                   : gfx::Display::ROTATE_270);
+}
+
+void ScreenOrientationController::LockToRotationMatchingOrientation(
+    blink::WebScreenOrientationLockType lock_orientation) {
+  // TODO(jonross): Update MaximizeModeController to allow rotation between
+  // two angles of an orientation (e.g. from ROTATE_0 to ROTATE_180, and from
+  // ROTATE_90 to ROTATE_270)
+  DisplayManager* display_manager = Shell::GetInstance()->display_manager();
+  if (!display_manager->HasInternalDisplay())
+    return;
+
+  gfx::Display::Rotation rotation =
+      display_manager->GetDisplayInfo(gfx::Display::InternalDisplayId())
+          .rotation();
+  if (natural_orientation_ == lock_orientation) {
+    if (rotation == gfx::Display::ROTATE_0 ||
+        rotation == gfx::Display::ROTATE_180) {
+      SetRotationLocked(true);
+    } else {
+      LockRotation(gfx::Display::ROTATE_0);
+    }
+  } else {
+    if (rotation == gfx::Display::ROTATE_90 ||
+        rotation == gfx::Display::ROTATE_270) {
+      SetRotationLocked(true);
+    } else {
+      LockRotation(gfx::Display::ROTATE_90);
+    }
+  }
+}
+
+void ScreenOrientationController::HandleScreenRotation(
+    const gfx::Vector3dF& lid) {
+  gfx::Vector3dF lid_flattened(lid.x(), lid.y(), 0.0f);
+  float lid_flattened_length = lid_flattened.Length();
+  // When the lid is close to being flat, don't change rotation as it is too
+  // sensitive to slight movements.
+  if (lid_flattened_length < kMinimumAccelerationScreenRotation)
+    return;
+
+  // The reference vector is the angle of gravity when the device is rotated
+  // clockwise by 45 degrees. Computing the angle between this vector and
+  // gravity we can easily determine the expected display rotation.
+  static const gfx::Vector3dF rotation_reference(-1.0f, -1.0f, 0.0f);
+
+  // Set the down vector to match the expected direction of gravity given the
+  // last configured rotation. This is used to enforce a stickiness that the
+  // user must overcome to rotate the display and prevents frequent rotations
+  // when holding the device near 45 degrees.
+  gfx::Vector3dF down(0.0f, 0.0f, 0.0f);
+  if (current_rotation_ == gfx::Display::ROTATE_0)
+    down.set_y(-1.0f);
+  else if (current_rotation_ == gfx::Display::ROTATE_90)
+    down.set_x(-1.0f);
+  else if (current_rotation_ == gfx::Display::ROTATE_180)
+    down.set_y(1.0f);
+  else
+    down.set_x(1.0f);
+
+  // Don't rotate if the screen has not passed the threshold.
+  if (AngleBetweenVectorsInDegrees(down, lid_flattened) <
+      kDisplayRotationStickyAngleDegrees) {
+    return;
+  }
+
+  float angle = ClockwiseAngleBetweenVectorsInDegrees(
+      rotation_reference, lid_flattened, gfx::Vector3dF(0.0f, 0.0f, -1.0f));
+
+  gfx::Display::Rotation new_rotation = gfx::Display::ROTATE_90;
+  if (angle < 90.0f)
+    new_rotation = gfx::Display::ROTATE_0;
+  else if (angle < 180.0f)
+    new_rotation = gfx::Display::ROTATE_270;
+  else if (angle < 270.0f)
+    new_rotation = gfx::Display::ROTATE_180;
+
+  if (new_rotation != current_rotation_)
+    SetDisplayRotation(new_rotation);
+}
+
+void ScreenOrientationController::LoadDisplayRotationProperties() {
+  DisplayManager* display_manager = Shell::GetInstance()->display_manager();
+  if (!display_manager->registered_internal_display_rotation_lock())
+    return;
+  SetDisplayRotation(display_manager->registered_internal_display_rotation());
+  SetRotationLocked(true);
+}
+
+}  // namespace ash