Modified: trunk/Source/WebCore/ChangeLog (268952 => 268953)
--- trunk/Source/WebCore/ChangeLog 2020-10-24 19:30:44 UTC (rev 268952)
+++ trunk/Source/WebCore/ChangeLog 2020-10-24 20:19:25 UTC (rev 268953)
@@ -1,3 +1,21 @@
+2020-10-24 Simon Fraser <[email protected]>
+
+ [LFC Display] Simplify display tree building
+ https://bugs.webkit.org/show_bug.cgi?id=218152
+
+ Reviewed by Zalan Bujtas.
+
+ Rather than tracking container/current child display boxes in various places in the code,
+ wrap it up in a small InsertionPosition struct and TreeBuilder::insert() which handles
+ the setFirstChild/setNextSibling logic.
+
+ * display/DisplayTreeBuilder.cpp:
+ (WebCore::Display::TreeBuilder::build const):
+ (WebCore::Display::TreeBuilder::insert const):
+ (WebCore::Display::TreeBuilder::buildInlineDisplayTree const):
+ (WebCore::Display::TreeBuilder::recursiveBuildDisplayTree const):
+ * display/DisplayTreeBuilder.h:
+
2020-10-24 Jer Noble <[email protected]>
[BigSur] Appending a new WebM init segment between Cluster elements throws an error
Modified: trunk/Source/WebCore/display/DisplayTreeBuilder.cpp (268952 => 268953)
--- trunk/Source/WebCore/display/DisplayTreeBuilder.cpp 2020-10-24 19:30:44 UTC (rev 268952)
+++ trunk/Source/WebCore/display/DisplayTreeBuilder.cpp 2020-10-24 20:19:25 UTC (rev 268953)
@@ -69,19 +69,31 @@
auto borderBoxRect = LayoutRect { Layout::BoxGeometry::borderBoxRect(geometry) };
auto offset = toLayoutSize(borderBoxRect.location());
- recursiveBuildDisplayTree(layoutState, offset, *rootLayoutBox.firstChild(), *rootDisplayContainerBox);
+ auto insertionPosition = InsertionPosition { *rootDisplayContainerBox };
+ recursiveBuildDisplayTree(layoutState, offset, *rootLayoutBox.firstChild(), insertionPosition);
+
LOG_WITH_STREAM(FormattingContextLayout, stream << "Display tree:\n" << displayTreeAsText(*rootDisplayContainerBox));
return makeUnique<Tree>(WTFMove(rootDisplayContainerBox));
}
-void TreeBuilder::buildInlineDisplayTree(const Layout::LayoutState& layoutState, LayoutSize offsetFromRoot, const Layout::ContainerBox& inlineFormattingRoot, ContainerBox& parentDisplayBox) const
+void TreeBuilder::insert(std::unique_ptr<Box>&& box, InsertionPosition& insertionPosition) const
{
+ if (insertionPosition.currentChild) {
+ auto boxPtr = box.get();
+ insertionPosition.currentChild->setNextSibling(WTFMove(box));
+ insertionPosition.currentChild = boxPtr;
+ } else {
+ insertionPosition.currentChild = box.get();
+ insertionPosition.container.setFirstChild(WTFMove(box));
+ }
+}
+
+void TreeBuilder::buildInlineDisplayTree(const Layout::LayoutState& layoutState, LayoutSize offsetFromRoot, const Layout::ContainerBox& inlineFormattingRoot, InsertionPosition& insertionPosition) const
+{
auto& inlineFormattingState = layoutState.establishedInlineFormattingState(inlineFormattingRoot);
- Box* previousSiblingBox = nullptr;
-
for (auto& run : inlineFormattingState.lineRuns()) {
auto& lineGeometry = inlineFormattingState.lines().at(run.lineIndex());
@@ -94,53 +106,39 @@
auto style = Style { run.layoutBox().style() };
auto textBox = makeUnique<TextBox>(snapRectToDevicePixels(runRect, m_pixelSnappingFactor), WTFMove(style), run);
- auto textBoxPtr = textBox.get();
- if (previousSiblingBox)
- previousSiblingBox->setNextSibling(WTFMove(textBox));
- else
- parentDisplayBox.setFirstChild(WTFMove(textBox));
-
- previousSiblingBox = textBoxPtr;
+ insert(WTFMove(textBox), insertionPosition);
}
}
-Box* TreeBuilder::recursiveBuildDisplayTree(const Layout::LayoutState& layoutState, LayoutSize offsetFromRoot, const Layout::Box& box, ContainerBox& parentDisplayBox, Box* previousSiblingBox) const
+void TreeBuilder::recursiveBuildDisplayTree(const Layout::LayoutState& layoutState, LayoutSize offsetFromRoot, const Layout::Box& box, InsertionPosition& insertionPosition) const
{
auto geometry = layoutState.geometryForBox(box);
auto displayBox = displayBoxForLayoutBox(geometry, box, offsetFromRoot);
- Box* result = displayBox.get();
+ insert(WTFMove(displayBox), insertionPosition);
- if (previousSiblingBox)
- previousSiblingBox->setNextSibling(WTFMove(displayBox));
- else
- parentDisplayBox.setFirstChild(WTFMove(displayBox));
-
if (!is<Layout::ContainerBox>(box))
- return result;
+ return;
auto& layoutContainerBox = downcast<Layout::ContainerBox>(box);
if (!layoutContainerBox.hasChild())
- return result;
+ return;
auto borderBoxRect = LayoutRect { Layout::BoxGeometry::borderBoxRect(geometry) };
offsetFromRoot += toLayoutSize(borderBoxRect.location());
- auto& displayContainerBox = downcast<ContainerBox>(*result);
-
+ auto positionForChildren = InsertionPosition { downcast<ContainerBox>(*insertionPosition.currentChild) };
+
if (layoutContainerBox.establishesInlineFormattingContext()) {
- buildInlineDisplayTree(layoutState, offsetFromRoot, downcast<Layout::ContainerBox>(layoutContainerBox), displayContainerBox);
- return result;
+ buildInlineDisplayTree(layoutState, offsetFromRoot, downcast<Layout::ContainerBox>(layoutContainerBox), positionForChildren);
+ return;
}
- Display::Box* currSiblingDisplayBox = nullptr;
for (auto& child : Layout::childrenOfType<Layout::Box>(layoutContainerBox)) {
if (layoutState.hasBoxGeometry(child))
- currSiblingDisplayBox = recursiveBuildDisplayTree(layoutState, offsetFromRoot, child, displayContainerBox, currSiblingDisplayBox);
+ recursiveBuildDisplayTree(layoutState, offsetFromRoot, child, positionForChildren);
}
-
- return result;
}
std::unique_ptr<Box> TreeBuilder::displayBoxForRootBox(const Layout::BoxGeometry& geometry, const Layout::ContainerBox& rootBox) const
Modified: trunk/Source/WebCore/display/DisplayTreeBuilder.h (268952 => 268953)
--- trunk/Source/WebCore/display/DisplayTreeBuilder.h 2020-10-24 19:30:44 UTC (rev 268952)
+++ trunk/Source/WebCore/display/DisplayTreeBuilder.h 2020-10-24 20:19:25 UTC (rev 268953)
@@ -57,12 +57,19 @@
std::unique_ptr<Tree> build(const Layout::LayoutState&) const;
private:
+ struct InsertionPosition {
+ Display::ContainerBox& container;
+ Display::Box* currentChild { nullptr };
+ };
+
std::unique_ptr<Box> displayBoxForRootBox(const Layout::BoxGeometry&, const Layout::ContainerBox&) const;
std::unique_ptr<Box> displayBoxForLayoutBox(const Layout::BoxGeometry&, const Layout::Box&, LayoutSize offsetFromRoot) const;
- Box* recursiveBuildDisplayTree(const Layout::LayoutState&, LayoutSize offsetFromRoot, const Layout::Box&, Display::ContainerBox& parentDisplayBox, Display::Box* previousSiblingBox = nullptr) const;
+ void recursiveBuildDisplayTree(const Layout::LayoutState&, LayoutSize offsetFromRoot, const Layout::Box&, InsertionPosition&) const;
- void buildInlineDisplayTree(const Layout::LayoutState&, LayoutSize offsetFromRoot, const Layout::ContainerBox&, Display::ContainerBox& parentDisplayBox) const;
+ void buildInlineDisplayTree(const Layout::LayoutState&, LayoutSize offsetFromRoot, const Layout::ContainerBox&, InsertionPosition&) const;
+
+ void insert(std::unique_ptr<Box>&&, InsertionPosition&) const;
float m_pixelSnappingFactor { 1 };
};
