widget/InputData.cpp
author Rob Wu <rob@robwu.nl>
Sat, 24 Sep 2016 11:16:32 +0200
changeset 320058 a41f871e2d1b37754bbd1001c36c075511b49342
parent 315214 3437f7cc1db20cee2193a43c2f21c4ec633e7753
permissions -rw-r--r--
Bug 1299411 - Decouple Port implementation from API r=aswan Decoupled the API from the implementation. From now on it is possible to create Port instances without generating an API. This allows us to internally use Ports to pass around messages with minimal overhead (in the form of unnecessary clones of messages). This will be used by native messaging. This commit has no behavioral change, it is mostly moving around some code and storing the internal message listener in a set. MozReview-Commit-ID: 4h0LNJvTH9R

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "InputData.h"

#include "mozilla/dom/Touch.h"
#include "nsDebug.h"
#include "nsThreadUtils.h"
#include "mozilla/MouseEvents.h"
#include "mozilla/TouchEvents.h"
#include "UnitTransforms.h"

namespace mozilla {

using namespace dom;

InputData::~InputData()
{
}

InputData::InputData(InputType aInputType)
  : mInputType(aInputType)
  , mTime(0)
  , modifiers(0)
{
}

InputData::InputData(InputType aInputType, uint32_t aTime, TimeStamp aTimeStamp,
                     Modifiers aModifiers)
  : mInputType(aInputType)
  , mTime(aTime)
  , mTimeStamp(aTimeStamp)
  , modifiers(aModifiers)
{
}

SingleTouchData::SingleTouchData(int32_t aIdentifier, ScreenIntPoint aScreenPoint,
                                 ScreenSize aRadius, float aRotationAngle,
                                 float aForce)
  : mIdentifier(aIdentifier)
  , mScreenPoint(aScreenPoint)
  , mRadius(aRadius)
  , mRotationAngle(aRotationAngle)
  , mForce(aForce)
{
}

SingleTouchData::SingleTouchData(int32_t aIdentifier,
                                 ParentLayerPoint aLocalScreenPoint,
                                 ScreenSize aRadius, float aRotationAngle,
                                 float aForce)
  : mIdentifier(aIdentifier)
  , mLocalScreenPoint(aLocalScreenPoint)
  , mRadius(aRadius)
  , mRotationAngle(aRotationAngle)
  , mForce(aForce)
{
}

SingleTouchData::SingleTouchData()
{
}

already_AddRefed<Touch> SingleTouchData::ToNewDOMTouch() const
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Can only create dom::Touch instances on main thread");
  RefPtr<Touch> touch = new Touch(mIdentifier,
                                  LayoutDeviceIntPoint::Truncate(mScreenPoint.x, mScreenPoint.y),
                                  LayoutDeviceIntPoint::Truncate(mRadius.width, mRadius.height),
                                  mRotationAngle,
                                  mForce);
  return touch.forget();
}

MultiTouchInput::MultiTouchInput(MultiTouchType aType, uint32_t aTime,
                                 TimeStamp aTimeStamp, Modifiers aModifiers)
  : InputData(MULTITOUCH_INPUT, aTime, aTimeStamp, aModifiers)
  , mType(aType)
  , mHandledByAPZ(false)
{
}

MultiTouchInput::MultiTouchInput()
  : InputData(MULTITOUCH_INPUT)
  , mHandledByAPZ(false)
{
}

MultiTouchInput::MultiTouchInput(const MultiTouchInput& aOther)
  : InputData(MULTITOUCH_INPUT, aOther.mTime, aOther.mTimeStamp, aOther.modifiers)
  , mType(aOther.mType)
  , mHandledByAPZ(aOther.mHandledByAPZ)
{
  mTouches.AppendElements(aOther.mTouches);
}

MultiTouchInput::MultiTouchInput(const WidgetTouchEvent& aTouchEvent)
  : InputData(MULTITOUCH_INPUT, aTouchEvent.mTime, aTouchEvent.mTimeStamp,
              aTouchEvent.mModifiers)
  , mHandledByAPZ(aTouchEvent.mFlags.mHandledByAPZ)
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Can only copy from WidgetTouchEvent on main thread");

  switch (aTouchEvent.mMessage) {
    case eTouchStart:
      mType = MULTITOUCH_START;
      break;
    case eTouchMove:
      mType = MULTITOUCH_MOVE;
      break;
    case eTouchEnd:
      mType = MULTITOUCH_END;
      break;
    case eTouchCancel:
      mType = MULTITOUCH_CANCEL;
      break;
    default:
      MOZ_ASSERT_UNREACHABLE("Did not assign a type to a MultiTouchInput");
      break;
  }

  for (size_t i = 0; i < aTouchEvent.mTouches.Length(); i++) {
    const Touch* domTouch = aTouchEvent.mTouches[i];

    // Extract data from weird interfaces.
    int32_t identifier = domTouch->Identifier();
    int32_t radiusX = domTouch->RadiusX();
    int32_t radiusY = domTouch->RadiusY();
    float rotationAngle = domTouch->RotationAngle();
    float force = domTouch->Force();

    SingleTouchData data(identifier,
                         ViewAs<ScreenPixel>(domTouch->mRefPoint,
                                             PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent),
                         ScreenSize(radiusX, radiusY),
                         rotationAngle,
                         force);

    mTouches.AppendElement(data);
  }
}

MultiTouchInput::MultiTouchInput(const WidgetMouseEvent& aMouseEvent)
  : InputData(MULTITOUCH_INPUT, aMouseEvent.mTime, aMouseEvent.mTimeStamp,
              aMouseEvent.mModifiers)
  , mHandledByAPZ(aMouseEvent.mFlags.mHandledByAPZ)
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Can only copy from WidgetMouseEvent on main thread");
  switch (aMouseEvent.mMessage) {
  case eMouseDown:
    mType = MULTITOUCH_START;
    break;
  case eMouseMove:
    mType = MULTITOUCH_MOVE;
    break;
  case eMouseUp:
    mType = MULTITOUCH_END;
    break;
  // The mouse pointer has been interrupted in an implementation-specific
  // manner, such as a synchronous event or action cancelling the touch, or a
  // touch point leaving the document window and going into a non-document
  // area capable of handling user interactions.
  case eMouseExitFromWidget:
    mType = MULTITOUCH_CANCEL;
    break;
  default:
    NS_WARNING("Did not assign a type to a MultiTouchInput");
    break;
  }

  mTouches.AppendElement(SingleTouchData(0,
                                         ViewAs<ScreenPixel>(aMouseEvent.mRefPoint,
                                                             PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent),
                                         ScreenSize(1, 1),
                                         180.0f,
                                         1.0f));
}

WidgetTouchEvent
MultiTouchInput::ToWidgetTouchEvent(nsIWidget* aWidget) const
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Can only convert To WidgetTouchEvent on main thread");

  EventMessage touchEventMessage = eVoidEvent;
  switch (mType) {
  case MULTITOUCH_START:
    touchEventMessage = eTouchStart;
    break;
  case MULTITOUCH_MOVE:
    touchEventMessage = eTouchMove;
    break;
  case MULTITOUCH_END:
    touchEventMessage = eTouchEnd;
    break;
  case MULTITOUCH_CANCEL:
    touchEventMessage = eTouchCancel;
    break;
  default:
    MOZ_ASSERT_UNREACHABLE("Did not assign a type to WidgetTouchEvent in MultiTouchInput");
    break;
  }

  WidgetTouchEvent event(true, touchEventMessage, aWidget);
  if (touchEventMessage == eVoidEvent) {
    return event;
  }

  event.mModifiers = this->modifiers;
  event.mTime = this->mTime;
  event.mTimeStamp = this->mTimeStamp;
  event.mFlags.mHandledByAPZ = mHandledByAPZ;

  for (size_t i = 0; i < mTouches.Length(); i++) {
    *event.mTouches.AppendElement() = mTouches[i].ToNewDOMTouch();
  }

  return event;
}

WidgetMouseEvent
MultiTouchInput::ToWidgetMouseEvent(nsIWidget* aWidget) const
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Can only convert To WidgetMouseEvent on main thread");

  EventMessage mouseEventMessage = eVoidEvent;
  switch (mType) {
    case MultiTouchInput::MULTITOUCH_START:
      mouseEventMessage = eMouseDown;
      break;
    case MultiTouchInput::MULTITOUCH_MOVE:
      mouseEventMessage = eMouseMove;
      break;
    case MultiTouchInput::MULTITOUCH_CANCEL:
    case MultiTouchInput::MULTITOUCH_END:
      mouseEventMessage = eMouseUp;
      break;
    default:
      MOZ_ASSERT_UNREACHABLE("Did not assign a type to WidgetMouseEvent");
      break;
  }

  WidgetMouseEvent event(true, mouseEventMessage, aWidget,
                         WidgetMouseEvent::eReal, WidgetMouseEvent::eNormal);

  const SingleTouchData& firstTouch = mTouches[0];
  event.mRefPoint.x = firstTouch.mScreenPoint.x;
  event.mRefPoint.y = firstTouch.mScreenPoint.y;

  event.mTime = mTime;
  event.button = WidgetMouseEvent::eLeftButton;
  event.inputSource = nsIDOMMouseEvent::MOZ_SOURCE_TOUCH;
  event.mModifiers = modifiers;
  event.mFlags.mHandledByAPZ = mHandledByAPZ;

  if (mouseEventMessage != eMouseMove) {
    event.mClickCount = 1;
  }

  return event;
}

int32_t
MultiTouchInput::IndexOfTouch(int32_t aTouchIdentifier)
{
  for (size_t i = 0; i < mTouches.Length(); i++) {
    if (mTouches[i].mIdentifier == aTouchIdentifier) {
      return (int32_t)i;
    }
  }
  return -1;
}

bool
MultiTouchInput::TransformToLocal(const ScreenToParentLayerMatrix4x4& aTransform)
{
  for (size_t i = 0; i < mTouches.Length(); i++) {
    Maybe<ParentLayerIntPoint> point = UntransformBy(aTransform, mTouches[i].mScreenPoint);
    if (!point) { 
      return false;
    }
    mTouches[i].mLocalScreenPoint = *point;
  }
  return true;
}

MouseInput::MouseInput()
  : InputData(MOUSE_INPUT)
  , mType(MOUSE_NONE)
  , mButtonType(NONE)
  , mInputSource(0)
  , mButtons(0)
  , mHandledByAPZ(false)
{
}

MouseInput::MouseInput(MouseType aType, ButtonType aButtonType,
                       uint16_t aInputSource, int16_t aButtons,
                       const ScreenPoint& aPoint, uint32_t aTime,
                       TimeStamp aTimeStamp, Modifiers aModifiers)
  : InputData(MOUSE_INPUT, aTime, aTimeStamp, aModifiers)
  , mType(aType)
  , mButtonType(aButtonType)
  , mInputSource(aInputSource)
  , mButtons(aButtons)
  , mOrigin(aPoint)
  , mHandledByAPZ(false)
{
}

MouseInput::MouseInput(const WidgetMouseEventBase& aMouseEvent)
  : InputData(MOUSE_INPUT, aMouseEvent.mTime, aMouseEvent.mTimeStamp,
              aMouseEvent.mModifiers)
  , mType(MOUSE_NONE)
  , mButtonType(NONE)
  , mInputSource(aMouseEvent.inputSource)
  , mButtons(aMouseEvent.buttons)
  , mHandledByAPZ(aMouseEvent.mFlags.mHandledByAPZ)
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Can only copy from WidgetTouchEvent on main thread");

  mButtonType = NONE;

  switch (aMouseEvent.button) {
    case WidgetMouseEventBase::eLeftButton:
      mButtonType = MouseInput::LEFT_BUTTON;
      break;
    case WidgetMouseEventBase::eMiddleButton:
      mButtonType = MouseInput::MIDDLE_BUTTON;
      break;
    case WidgetMouseEventBase::eRightButton:
      mButtonType = MouseInput::RIGHT_BUTTON;
      break;
  }

  switch (aMouseEvent.mMessage) {
    case eMouseMove:
      mType = MOUSE_MOVE;
      break;
    case eMouseUp:
      mType = MOUSE_UP;
      break;
    case eMouseDown:
      mType = MOUSE_DOWN;
      break;
    case eDragStart:
      mType = MOUSE_DRAG_START;
      break;
    case eDragEnd:
      mType = MOUSE_DRAG_END;
      break;
    case eMouseEnterIntoWidget:
      mType = MOUSE_WIDGET_ENTER;
      break;
    case eMouseExitFromWidget:
      mType = MOUSE_WIDGET_EXIT;
      break;
    default:
      MOZ_ASSERT_UNREACHABLE("Mouse event type not supported");
      break;
  }

  mOrigin =
    ScreenPoint(ViewAs<ScreenPixel>(aMouseEvent.mRefPoint,
      PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent));
}

bool
MouseInput::IsLeftButton() const
{
  return mButtonType == LEFT_BUTTON;
}

bool
MouseInput::TransformToLocal(const ScreenToParentLayerMatrix4x4& aTransform)
{
  Maybe<ParentLayerPoint> point = UntransformBy(aTransform, mOrigin);
  if (!point) {
    return false;
  }
  mLocalOrigin = *point;

  return true;
}

WidgetMouseEvent
MouseInput::ToWidgetMouseEvent(nsIWidget* aWidget) const
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Can only convert To WidgetTouchEvent on main thread");

  EventMessage msg = eVoidEvent;
  uint32_t clickCount = 0;
  switch (mType) {
    case MOUSE_MOVE:
      msg = eMouseMove;
      break;
    case MOUSE_UP:
      msg = eMouseUp;
      clickCount = 1;
      break;
    case MOUSE_DOWN:
      msg = eMouseDown;
      clickCount = 1;
      break;
    case MOUSE_DRAG_START:
      msg = eDragStart;
      break;
    case MOUSE_DRAG_END:
      msg = eDragEnd;
      break;
    case MOUSE_WIDGET_ENTER:
      msg = eMouseEnterIntoWidget;
      break;
    case MOUSE_WIDGET_EXIT:
      msg = eMouseExitFromWidget;
      break;
    default:
      MOZ_ASSERT_UNREACHABLE("Did not assign a type to WidgetMouseEvent in MouseInput");
      break;
  }

  WidgetMouseEvent event(true, msg, aWidget, WidgetMouseEvent::eReal, WidgetMouseEvent::eNormal);

  if (msg == eVoidEvent) {
    return event;
  }

  switch (mButtonType) {
    case MouseInput::LEFT_BUTTON:
      event.button = WidgetMouseEventBase::eLeftButton;
      break;
    case MouseInput::MIDDLE_BUTTON:
      event.button = WidgetMouseEventBase::eMiddleButton;
      break;
    case MouseInput::RIGHT_BUTTON:
      event.button = WidgetMouseEventBase::eRightButton;
      break;
    case MouseInput::NONE:
    default:
      break;
  }

  event.buttons = mButtons;
  event.mModifiers = modifiers;
  event.mTime = mTime;
  event.mTimeStamp = mTimeStamp;
  event.mFlags.mHandledByAPZ = mHandledByAPZ;
  event.mRefPoint =
    RoundedToInt(ViewAs<LayoutDevicePixel>(mOrigin,
      PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent));
  event.mClickCount = clickCount;
  event.inputSource = mInputSource;
  event.mIgnoreRootScrollFrame = true;

  return event;
}

PanGestureInput::PanGestureInput()
  : InputData(PANGESTURE_INPUT)
  , mLineOrPageDeltaX(0)
  , mLineOrPageDeltaY(0)
  , mUserDeltaMultiplierX(1.0)
  , mUserDeltaMultiplierY(1.0)
  , mHandledByAPZ(false)
  , mFollowedByMomentum(false)
  , mRequiresContentResponseIfCannotScrollHorizontallyInStartDirection(false)
{
}

PanGestureInput::PanGestureInput(PanGestureType aType, uint32_t aTime,
                                 TimeStamp aTimeStamp,
                                 const ScreenPoint& aPanStartPoint,
                                 const ScreenPoint& aPanDisplacement,
                                 Modifiers aModifiers)
  : InputData(PANGESTURE_INPUT, aTime, aTimeStamp, aModifiers)
  , mType(aType)
  , mPanStartPoint(aPanStartPoint)
  , mPanDisplacement(aPanDisplacement)
  , mLineOrPageDeltaX(0)
  , mLineOrPageDeltaY(0)
  , mUserDeltaMultiplierX(1.0)
  , mUserDeltaMultiplierY(1.0)
  , mHandledByAPZ(false)
  , mFollowedByMomentum(false)
  , mRequiresContentResponseIfCannotScrollHorizontallyInStartDirection(false)
{
}

bool
PanGestureInput::IsMomentum() const
{
  switch (mType) {
    case PanGestureInput::PANGESTURE_MOMENTUMSTART:
    case PanGestureInput::PANGESTURE_MOMENTUMPAN:
    case PanGestureInput::PANGESTURE_MOMENTUMEND:
      return true;
    default:
      return false;
  }
}

WidgetWheelEvent
PanGestureInput::ToWidgetWheelEvent(nsIWidget* aWidget) const
{
  WidgetWheelEvent wheelEvent(true, eWheel, aWidget);
  wheelEvent.mModifiers = this->modifiers;
  wheelEvent.mTime = mTime;
  wheelEvent.mTimeStamp = mTimeStamp;
  wheelEvent.mRefPoint =
    RoundedToInt(ViewAs<LayoutDevicePixel>(mPanStartPoint,
      PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent));
  wheelEvent.buttons = 0;
  wheelEvent.mDeltaMode = nsIDOMWheelEvent::DOM_DELTA_PIXEL;
  wheelEvent.mMayHaveMomentum = true; // pan inputs may have momentum
  wheelEvent.mIsMomentum = IsMomentum();
  wheelEvent.mLineOrPageDeltaX = mLineOrPageDeltaX;
  wheelEvent.mLineOrPageDeltaY = mLineOrPageDeltaY;
  wheelEvent.mDeltaX = mPanDisplacement.x;
  wheelEvent.mDeltaY = mPanDisplacement.y;
  wheelEvent.mFlags.mHandledByAPZ = mHandledByAPZ;
  return wheelEvent;
}

bool
PanGestureInput::TransformToLocal(const ScreenToParentLayerMatrix4x4& aTransform)
{ 
  Maybe<ParentLayerPoint> panStartPoint = UntransformBy(aTransform, mPanStartPoint);
  if (!panStartPoint) {
    return false;
  }
  mLocalPanStartPoint = *panStartPoint;
  
  Maybe<ParentLayerPoint> panDisplacement = UntransformVector(aTransform, mPanDisplacement, mPanStartPoint);
  if (!panDisplacement) {
    return false;
  }
  mLocalPanDisplacement = *panDisplacement;
  return true;
}

ScreenPoint
PanGestureInput::UserMultipliedPanDisplacement() const
{
  return ScreenPoint(mPanDisplacement.x * mUserDeltaMultiplierX,
                     mPanDisplacement.y * mUserDeltaMultiplierY);
}

ParentLayerPoint
PanGestureInput::UserMultipliedLocalPanDisplacement() const
{
  return ParentLayerPoint(mLocalPanDisplacement.x * mUserDeltaMultiplierX,
                          mLocalPanDisplacement.y * mUserDeltaMultiplierY);
}

PinchGestureInput::PinchGestureInput()
  : InputData(PINCHGESTURE_INPUT)
{
}

PinchGestureInput::PinchGestureInput(PinchGestureType aType, uint32_t aTime,
                                     TimeStamp aTimeStamp,
                                     const ParentLayerPoint& aLocalFocusPoint,
                                     ParentLayerCoord aCurrentSpan,
                                     ParentLayerCoord aPreviousSpan,
                                     Modifiers aModifiers)
  : InputData(PINCHGESTURE_INPUT, aTime, aTimeStamp, aModifiers)
  , mType(aType)
  , mLocalFocusPoint(aLocalFocusPoint)
  , mCurrentSpan(aCurrentSpan)
  , mPreviousSpan(aPreviousSpan)
{
}

bool
PinchGestureInput::TransformToLocal(const ScreenToParentLayerMatrix4x4& aTransform)
{ 
  Maybe<ParentLayerPoint> point = UntransformBy(aTransform, mFocusPoint);
  if (!point) {
    return false;
  }
  mLocalFocusPoint = *point;
  return true;
}

TapGestureInput::TapGestureInput()
  : InputData(TAPGESTURE_INPUT)
{
}

TapGestureInput::TapGestureInput(TapGestureType aType, uint32_t aTime,
                                 TimeStamp aTimeStamp,
                                 const ScreenIntPoint& aPoint,
                                 Modifiers aModifiers)
  : InputData(TAPGESTURE_INPUT, aTime, aTimeStamp, aModifiers)
  , mType(aType)
  , mPoint(aPoint)
{
}

TapGestureInput::TapGestureInput(TapGestureType aType, uint32_t aTime,
                                 TimeStamp aTimeStamp,
                                 const ParentLayerPoint& aLocalPoint,
                                 Modifiers aModifiers)
  : InputData(TAPGESTURE_INPUT, aTime, aTimeStamp, aModifiers)
  , mType(aType)
  , mLocalPoint(aLocalPoint)
{
}

bool
TapGestureInput::TransformToLocal(const ScreenToParentLayerMatrix4x4& aTransform)
{
  Maybe<ParentLayerIntPoint> point = UntransformBy(aTransform, mPoint);
  if (!point) {
    return false;
  }
  mLocalPoint = *point;
  return true;
}

ScrollWheelInput::ScrollWheelInput()
  : InputData(SCROLLWHEEL_INPUT)
  , mHandledByAPZ(false)
  , mLineOrPageDeltaX(0)
  , mLineOrPageDeltaY(0)
  , mScrollSeriesNumber(0)
  , mUserDeltaMultiplierX(1.0)
  , mUserDeltaMultiplierY(1.0)
  , mMayHaveMomentum(false)
  , mIsMomentum(false)
{
}

ScrollWheelInput::ScrollWheelInput(uint32_t aTime, TimeStamp aTimeStamp,
                                   Modifiers aModifiers, ScrollMode aScrollMode,
                                   ScrollDeltaType aDeltaType,
                                   const ScreenPoint& aOrigin, double aDeltaX,
                                   double aDeltaY,
                                   bool aAllowToOverrideSystemScrollSpeed)
  : InputData(SCROLLWHEEL_INPUT, aTime, aTimeStamp, aModifiers)
  , mDeltaType(aDeltaType)
  , mScrollMode(aScrollMode)
  , mOrigin(aOrigin)
  , mHandledByAPZ(false)
  , mDeltaX(aDeltaX)
  , mDeltaY(aDeltaY)
  , mLineOrPageDeltaX(0)
  , mLineOrPageDeltaY(0)
  , mScrollSeriesNumber(0)
  , mUserDeltaMultiplierX(1.0)
  , mUserDeltaMultiplierY(1.0)
  , mMayHaveMomentum(false)
  , mIsMomentum(false)
  , mAllowToOverrideSystemScrollSpeed(aAllowToOverrideSystemScrollSpeed)
{
}

ScrollWheelInput::ScrollWheelInput(const WidgetWheelEvent& aWheelEvent)
  : InputData(SCROLLWHEEL_INPUT, aWheelEvent.mTime, aWheelEvent.mTimeStamp,
              aWheelEvent.mModifiers)
  , mDeltaType(DeltaTypeForDeltaMode(aWheelEvent.mDeltaMode))
  , mScrollMode(SCROLLMODE_INSTANT)
  , mHandledByAPZ(aWheelEvent.mFlags.mHandledByAPZ)
  , mDeltaX(aWheelEvent.mDeltaX)
  , mDeltaY(aWheelEvent.mDeltaY)
  , mLineOrPageDeltaX(aWheelEvent.mLineOrPageDeltaX)
  , mLineOrPageDeltaY(aWheelEvent.mLineOrPageDeltaY)
  , mScrollSeriesNumber(0)
  , mUserDeltaMultiplierX(1.0)
  , mUserDeltaMultiplierY(1.0)
  , mMayHaveMomentum(aWheelEvent.mMayHaveMomentum)
  , mIsMomentum(aWheelEvent.mIsMomentum)
  , mAllowToOverrideSystemScrollSpeed(
      aWheelEvent.mAllowToOverrideSystemScrollSpeed)
{
  mOrigin =
    ScreenPoint(ViewAs<ScreenPixel>(aWheelEvent.mRefPoint,
      PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent));
}

ScrollWheelInput::ScrollDeltaType
ScrollWheelInput::DeltaTypeForDeltaMode(uint32_t aDeltaMode)
{
  switch (aDeltaMode) {
  case nsIDOMWheelEvent::DOM_DELTA_LINE:
    return SCROLLDELTA_LINE;
  case nsIDOMWheelEvent::DOM_DELTA_PAGE:
    return SCROLLDELTA_PAGE;
  case nsIDOMWheelEvent::DOM_DELTA_PIXEL:
    return SCROLLDELTA_PIXEL;
  default:
    MOZ_CRASH();
  }
  return SCROLLDELTA_LINE;
}

uint32_t
ScrollWheelInput::DeltaModeForDeltaType(ScrollDeltaType aDeltaType)
{
  switch (aDeltaType) {
  case ScrollWheelInput::SCROLLDELTA_LINE:
    return nsIDOMWheelEvent::DOM_DELTA_LINE;
  case ScrollWheelInput::SCROLLDELTA_PAGE:
    return nsIDOMWheelEvent::DOM_DELTA_PAGE;
  case ScrollWheelInput::SCROLLDELTA_PIXEL:
  default:
    return nsIDOMWheelEvent::DOM_DELTA_PIXEL;
  }
}

nsIScrollableFrame::ScrollUnit
ScrollWheelInput::ScrollUnitForDeltaType(ScrollDeltaType aDeltaType)
{
  switch (aDeltaType) {
  case SCROLLDELTA_LINE:
    return nsIScrollableFrame::LINES;
  case SCROLLDELTA_PAGE:
    return nsIScrollableFrame::PAGES;
  case SCROLLDELTA_PIXEL:
    return nsIScrollableFrame::DEVICE_PIXELS;
  default:
    MOZ_CRASH();
  }
  return nsIScrollableFrame::LINES;
}

WidgetWheelEvent
ScrollWheelInput::ToWidgetWheelEvent(nsIWidget* aWidget) const
{
  WidgetWheelEvent wheelEvent(true, eWheel, aWidget);
  wheelEvent.mModifiers = this->modifiers;
  wheelEvent.mTime = mTime;
  wheelEvent.mTimeStamp = mTimeStamp;
  wheelEvent.mRefPoint =
    RoundedToInt(ViewAs<LayoutDevicePixel>(mOrigin,
      PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent));
  wheelEvent.buttons = 0;
  wheelEvent.mDeltaMode = DeltaModeForDeltaType(mDeltaType);
  wheelEvent.mMayHaveMomentum = mMayHaveMomentum;
  wheelEvent.mIsMomentum = mIsMomentum;
  wheelEvent.mDeltaX = mDeltaX;
  wheelEvent.mDeltaY = mDeltaY;
  wheelEvent.mLineOrPageDeltaX = mLineOrPageDeltaX;
  wheelEvent.mLineOrPageDeltaY = mLineOrPageDeltaY;
  wheelEvent.mAllowToOverrideSystemScrollSpeed =
    mAllowToOverrideSystemScrollSpeed;
  wheelEvent.mFlags.mHandledByAPZ = mHandledByAPZ;
  return wheelEvent;
}

bool
ScrollWheelInput::TransformToLocal(const ScreenToParentLayerMatrix4x4& aTransform)
{
  Maybe<ParentLayerPoint> point = UntransformBy(aTransform, mOrigin);
  if (!point) {
    return false;
  }
  mLocalOrigin = *point;
  return true;
}

bool
ScrollWheelInput::IsCustomizedByUserPrefs() const
{
  return mUserDeltaMultiplierX != 1.0 ||
         mUserDeltaMultiplierY != 1.0;
}

} // namespace mozilla