Files
sousa-gecko/layout/generic/ScrollPositionUpdate.cpp
T
Botond Ballo 35ceb27bb2 Bug 1965670 - Introduce a mechanism for the main thread to specify whether a smooth scroll should scroll the visual or layout viewport. r=hiro,layout-reviewers
For now, the main thread always requests smooth scrolling of the
visual viewport, to reflect that this what APZ actually does.

This is wrong for some call sites, and will be fixed in later patches
in this series.

Differential Revision: https://phabricator.services.mozilla.com/D261624
2025-08-22 02:03:04 +00:00

146 lines
5.0 KiB
C++

/* 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 "ScrollPositionUpdate.h"
#include <ostream>
#include "mozilla/Assertions.h"
namespace mozilla {
static ScrollGenerationCounter sGenerationCounter;
ScrollPositionUpdate::ScrollPositionUpdate()
: mType(ScrollUpdateType::Absolute),
mScrollMode(ScrollMode::Normal),
mScrollOrigin(ScrollOrigin::None),
mTriggeredByScript(ScrollTriggeredByScript::No) {}
/*static*/
ScrollPositionUpdate ScrollPositionUpdate::NewScrollframe(
nsPoint aInitialPosition) {
ScrollPositionUpdate ret;
ret.mScrollGeneration = sGenerationCounter.NewMainThreadGeneration();
ret.mScrollMode = ScrollMode::Instant;
ret.mDestination = CSSPoint::FromAppUnits(aInitialPosition);
return ret;
}
/*static*/
ScrollPositionUpdate ScrollPositionUpdate::NewScroll(ScrollOrigin aOrigin,
nsPoint aDestination) {
MOZ_ASSERT(aOrigin != ScrollOrigin::NotSpecified);
MOZ_ASSERT(aOrigin != ScrollOrigin::None);
ScrollPositionUpdate ret;
ret.mScrollGeneration = sGenerationCounter.NewMainThreadGeneration();
ret.mType = ScrollUpdateType::Absolute;
ret.mScrollMode = ScrollMode::Instant;
ret.mScrollOrigin = aOrigin;
ret.mDestination = CSSPoint::FromAppUnits(aDestination);
return ret;
}
/*static*/
ScrollPositionUpdate ScrollPositionUpdate::NewRelativeScroll(
nsPoint aSource, nsPoint aDestination) {
ScrollPositionUpdate ret;
ret.mScrollGeneration = sGenerationCounter.NewMainThreadGeneration();
ret.mType = ScrollUpdateType::Relative;
ret.mScrollMode = ScrollMode::Instant;
ret.mScrollOrigin = ScrollOrigin::Relative;
ret.mDestination = CSSPoint::FromAppUnits(aDestination);
ret.mSource = CSSPoint::FromAppUnits(aSource);
return ret;
}
/*static*/
ScrollPositionUpdate ScrollPositionUpdate::NewSmoothScroll(
ScrollMode aMode, ScrollOrigin aOrigin, nsPoint aDestination,
ScrollTriggeredByScript aTriggeredByScript,
UniquePtr<ScrollSnapTargetIds> aSnapTargetIds,
ViewportType aViewportToScroll) {
MOZ_ASSERT(aOrigin != ScrollOrigin::NotSpecified);
MOZ_ASSERT(aOrigin != ScrollOrigin::None);
MOZ_ASSERT(aMode == ScrollMode::Smooth || aMode == ScrollMode::SmoothMsd);
ScrollPositionUpdate ret;
ret.mScrollGeneration = sGenerationCounter.NewMainThreadGeneration();
ret.mType = ScrollUpdateType::Absolute;
ret.mScrollMode = aMode;
ret.mScrollOrigin = aOrigin;
ret.mDestination = CSSPoint::FromAppUnits(aDestination);
ret.mViewportType = aViewportToScroll;
ret.mTriggeredByScript = aTriggeredByScript;
if (aSnapTargetIds) {
ret.mSnapTargetIds = *aSnapTargetIds;
}
return ret;
}
/*static*/
ScrollPositionUpdate ScrollPositionUpdate::NewPureRelativeScroll(
ScrollOrigin aOrigin, ScrollMode aMode, const nsPoint& aDelta) {
MOZ_ASSERT(aOrigin != ScrollOrigin::NotSpecified);
MOZ_ASSERT(aOrigin != ScrollOrigin::None);
ScrollPositionUpdate ret;
ret.mScrollGeneration = sGenerationCounter.NewMainThreadGeneration();
ret.mType = ScrollUpdateType::PureRelative;
ret.mScrollMode = aMode;
// Pure relative scrolls always apply to the visual viewport.
// FIXME: Should they? (Bug 1984224)
ret.mViewportType = ViewportType::Visual;
ret.mScrollOrigin = aOrigin;
ret.mDelta = CSSPoint::FromAppUnits(aDelta);
return ret;
}
bool ScrollPositionUpdate::operator==(
const ScrollPositionUpdate& aOther) const {
// instances are immutable, and all the fields are set when the generation
// is set. So if the generation matches, these instances are identical.
return mScrollGeneration == aOther.mScrollGeneration;
}
MainThreadScrollGeneration ScrollPositionUpdate::GetGeneration() const {
return mScrollGeneration;
}
ScrollUpdateType ScrollPositionUpdate::GetType() const { return mType; }
ScrollMode ScrollPositionUpdate::GetMode() const { return mScrollMode; }
ScrollOrigin ScrollPositionUpdate::GetOrigin() const { return mScrollOrigin; }
CSSPoint ScrollPositionUpdate::GetDestination() const {
MOZ_ASSERT(mType == ScrollUpdateType::Absolute ||
mType == ScrollUpdateType::Relative);
return mDestination;
}
CSSPoint ScrollPositionUpdate::GetSource() const {
MOZ_ASSERT(mType == ScrollUpdateType::Relative);
return mSource;
}
CSSPoint ScrollPositionUpdate::GetDelta() const {
MOZ_ASSERT(mType == ScrollUpdateType::PureRelative);
return mDelta;
}
std::ostream& operator<<(std::ostream& aStream,
const ScrollPositionUpdate& aUpdate) {
aStream << "{ gen=" << aUpdate.mScrollGeneration << ", type=" << aUpdate.mType
<< ", mode=" << aUpdate.mScrollMode
<< ", origin=" << aUpdate.mScrollOrigin
<< ", dst=" << aUpdate.mDestination << ", src=" << aUpdate.mSource
<< ", delta=" << aUpdate.mDelta
<< ", triggered by script=" << aUpdate.WasTriggeredByScript() << " }";
return aStream;
}
} // namespace mozilla