gecko-dev/layout/painting/HitTestInfo.cpp
Daniel Holbert f913735c40 Bug 1733727 part 3: Use StaticAutoPtr to manage lifetime of various "gFoo" static global variables in layout. r=jfkthame
This patch doesn't change any user-observable behavior.

StaticAutoPtr lets us remove a handful of explicit 'delete' statements, by
making deletion happen automatically when these variables are cleared.

Differential Revision: https://phabricator.services.mozilla.com/D127337
2021-10-02 18:59:11 +00:00

73 lines
2.1 KiB
C++

/* -*- 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, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "HitTestInfo.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/webrender/WebRenderAPI.h"
#include "nsDisplayList.h"
#include "nsIFrame.h"
#include "mozilla/layers/ScrollableLayerGuid.h"
namespace mozilla {
static StaticAutoPtr<const HitTestInfo> gEmptyHitTestInfo;
const HitTestInfo& HitTestInfo::Empty() {
if (gEmptyHitTestInfo) {
gEmptyHitTestInfo = new HitTestInfo();
}
return *gEmptyHitTestInfo;
}
void HitTestInfo::Shutdown() { gEmptyHitTestInfo = nullptr; }
using ViewID = layers::ScrollableLayerGuid::ViewID;
ViewID HitTestInfo::GetViewId(wr::DisplayListBuilder& aBuilder,
const ActiveScrolledRoot* aASR) const {
if (mScrollTarget) {
return *mScrollTarget;
}
Maybe<ViewID> fixedTarget = aBuilder.GetContainingFixedPosScrollTarget(aASR);
if (fixedTarget) {
return *fixedTarget;
}
if (aASR) {
return aASR->GetViewId();
}
return layers::ScrollableLayerGuid::NULL_SCROLL_ID;
}
void HitTestInfo::Initialize(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame) {
if (!aBuilder->BuildCompositorHitTestInfo()) {
return;
}
mInfo = aFrame->GetCompositorHitTestInfo(aBuilder);
if (mInfo != gfx::CompositorHitTestInvisibleToHit) {
mArea = aFrame->GetCompositorHitTestArea(aBuilder);
InitializeScrollTarget(aBuilder);
}
}
void HitTestInfo::InitializeScrollTarget(nsDisplayListBuilder* aBuilder) {
if (aBuilder->GetCurrentScrollbarDirection().isSome()) {
// In the case of scrollbar frames, we use the scrollbar's target
// scrollframe instead of the scrollframe with which the scrollbar actually
// moves.
MOZ_ASSERT(Info().contains(CompositorHitTestFlags::eScrollbar));
mScrollTarget = Some(aBuilder->GetCurrentScrollbarTarget());
}
}
} // namespace mozilla