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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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,
#include "WheelEvent.h"
#include "mozilla/dom/MouseEventBinding.h"
#include "mozilla/MouseEvents.h"
namespace mozilla::dom {
WheelEvent::WheelEvent(EventTarget* aOwner, nsPresContext* aPresContext,
WidgetWheelEvent* aWheelEvent)
: MouseEvent(aOwner, aPresContext,
aWheelEvent
? aWheelEvent
: new WidgetWheelEvent(false, eVoidEvent, nullptr)),
mAppUnitsPerDevPixel(0) {
if (aWheelEvent) {
mEventIsInternal = false;
// If the delta mode is pixel, the WidgetWheelEvent's delta values are in
// device pixels. However, JS contents need the delta values in CSS pixels.
// We should store the value of mAppUnitsPerDevPixel here because
// it might be changed by changing zoom or something.
if (aWheelEvent->mDeltaMode == WheelEvent_Binding::DOM_DELTA_PIXEL) {
mAppUnitsPerDevPixel = aPresContext->AppUnitsPerDevPixel();
}
} else {
mEventIsInternal = true;
mEvent->mRefPoint = LayoutDeviceIntPoint(0, 0);
mEvent->AsWheelEvent()->mInputSource =
MouseEvent_Binding::MOZ_SOURCE_UNKNOWN;
}
}
void WheelEvent::InitWheelEventInternal(
const nsAString& aType, bool aCanBubble, bool aCancelable,
nsGlobalWindowInner* aView, int32_t aDetail, double aScreenX,
double aScreenY, double aClientX, double aClientY, uint16_t aButton,
EventTarget* aRelatedTarget, const nsAString& aModifiersList,
double aDeltaX, double aDeltaY, double aDeltaZ, uint32_t aDeltaMode) {
NS_ENSURE_TRUE_VOID(!mEvent->mFlags.mIsBeingDispatched);
MouseEvent::InitMouseEventInternal(
aType, aCanBubble, aCancelable, aView, aDetail, aScreenX, aScreenY,
aClientX, aClientY, aButton, aRelatedTarget, aModifiersList);
WidgetWheelEvent* wheelEvent = mEvent->AsWheelEvent();
// When specified by the caller (for JS-created events), don't mess with the
// delta mode.
wheelEvent->mDeltaModeCheckingState =
WidgetWheelEvent::DeltaModeCheckingState::Checked;
wheelEvent->mDeltaX = aDeltaX;
wheelEvent->mDeltaY = aDeltaY;
wheelEvent->mDeltaZ = aDeltaZ;
wheelEvent->mDeltaMode = aDeltaMode;
wheelEvent->mAllowToOverrideSystemScrollSpeed = false;
}
int32_t WheelEvent::WheelDeltaX(CallerType aCallerType) {
WidgetWheelEvent* ev = mEvent->AsWheelEvent();
if (ev->mWheelTicksX != 0.0) {
return int32_t(-ev->mWheelTicksX * kNativeTicksToWheelDelta);
}
if (IsTrusted()) {
// We always return pixels regardless of the checking-state.
double pixelDelta =
ev->mDeltaMode == WheelEvent_Binding::DOM_DELTA_PIXEL
? CSSCoord(DevToCssPixels(ev->OverriddenDeltaX()))
: ev->OverriddenDeltaX() *
CSSPixel::FromAppUnits(ev->mScrollAmount.width).Rounded();
return int32_t(-std::round(pixelDelta * kTrustedDeltaToWheelDelta));
}
return int32_t(-std::round(DeltaX(aCallerType))); // This matches Safari.
}
int32_t WheelEvent::WheelDeltaY(CallerType aCallerType) {
WidgetWheelEvent* ev = mEvent->AsWheelEvent();
if (ev->mWheelTicksY != 0.0) {
return int32_t(-ev->mWheelTicksY * kNativeTicksToWheelDelta);
}
if (IsTrusted()) {
double pixelDelta =
ev->mDeltaMode == WheelEvent_Binding::DOM_DELTA_PIXEL
? CSSCoord(DevToCssPixels(ev->OverriddenDeltaY()))
: ev->OverriddenDeltaY() *
CSSPixel::FromAppUnits(ev->mScrollAmount.height).Rounded();
return int32_t(-std::round(pixelDelta * kTrustedDeltaToWheelDelta));
}
return int32_t(-std::round(DeltaY(aCallerType))); // This matches Safari.
}
double WheelEvent::ToWebExposedDelta(WidgetWheelEvent& aWidgetEvent,
double aDelta, nscoord aLineOrPageAmount,
CallerType aCallerType) {
using DeltaModeCheckingState = WidgetWheelEvent::DeltaModeCheckingState;
if (aCallerType != CallerType::System) {
if (aWidgetEvent.mDeltaModeCheckingState ==
DeltaModeCheckingState::Unknown) {
aWidgetEvent.mDeltaModeCheckingState = DeltaModeCheckingState::Unchecked;
}
if (aWidgetEvent.mDeltaModeCheckingState ==
DeltaModeCheckingState::Unchecked &&
aWidgetEvent.mDeltaMode == WheelEvent_Binding::DOM_DELTA_LINE) {
return aDelta * CSSPixel::FromAppUnits(aLineOrPageAmount).Rounded();
}
}
return DevToCssPixels(aDelta);
}
double WheelEvent::DeltaX(CallerType aCallerType) {
WidgetWheelEvent* ev = mEvent->AsWheelEvent();
return ToWebExposedDelta(*ev, ev->OverriddenDeltaX(), ev->mScrollAmount.width,
aCallerType);
}
double WheelEvent::DeltaY(CallerType aCallerType) {
WidgetWheelEvent* ev = mEvent->AsWheelEvent();
return ToWebExposedDelta(*ev, ev->OverriddenDeltaY(),
ev->mScrollAmount.height, aCallerType);
}
double WheelEvent::DeltaZ(CallerType aCallerType) {
WidgetWheelEvent* ev = mEvent->AsWheelEvent();
// XXX Unclear what scroll amount we should use for deltaZ...
auto amount = std::max(ev->mScrollAmount.width, ev->mScrollAmount.height);
return ToWebExposedDelta(*ev, ev->mDeltaZ, amount, aCallerType);
}
uint32_t WheelEvent::DeltaMode(CallerType aCallerType) {
using DeltaModeCheckingState = WidgetWheelEvent::DeltaModeCheckingState;
WidgetWheelEvent* ev = mEvent->AsWheelEvent();
uint32_t mode = ev->mDeltaMode;
if (aCallerType != CallerType::System) {
if (ev->mDeltaModeCheckingState == DeltaModeCheckingState::Unknown) {
ev->mDeltaModeCheckingState = DeltaModeCheckingState::Checked;
} else if (ev->mDeltaModeCheckingState ==
DeltaModeCheckingState::Unchecked &&
mode == WheelEvent_Binding::DOM_DELTA_LINE) {
return WheelEvent_Binding::DOM_DELTA_PIXEL;
}
}
return mode;
}
already_AddRefed<WheelEvent> WheelEvent::Constructor(
const GlobalObject& aGlobal, const nsAString& aType,
const WheelEventInit& aParam) {
nsCOMPtr<EventTarget> t = do_QueryInterface(aGlobal.GetAsSupports());
RefPtr<WheelEvent> e = new WheelEvent(t, nullptr, nullptr);
bool trusted = e->Init(t);
e->InitWheelEventInternal(
aType, aParam.mBubbles, aParam.mCancelable, aParam.mView, aParam.mDetail,
aParam.mScreenX, aParam.mScreenY, aParam.mClientX, aParam.mClientY,
aParam.mButton, aParam.mRelatedTarget, u""_ns, aParam.mDeltaX,
aParam.mDeltaY, aParam.mDeltaZ, aParam.mDeltaMode);
e->InitializeExtraMouseEventDictionaryMembers(aParam);
e->SetTrusted(trusted);
e->SetComposed(aParam.mComposed);
return e.forget();
}
} // namespace mozilla::dom
using namespace mozilla;
using namespace mozilla::dom;
already_AddRefed<WheelEvent> NS_NewDOMWheelEvent(EventTarget* aOwner,
nsPresContext* aPresContext,
WidgetWheelEvent* aEvent) {
RefPtr<WheelEvent> it = new WheelEvent(aOwner, aPresContext, aEvent);
return it.forget();
}