Changeset 263639 in webkit

Timestamp:

Jun 28, 2020 5:00:58 PM (4 years ago)

Author:

Alan Bujtas

Message:

[LFC][Painting] Use the table section as the paint container for table cells
​https://bugs.webkit.org/show_bug.cgi?id=213693

Reviewed by Antti Koivisto.

The cell's containing block is the table box (skipping both the row and the section),
but it's positioned relative to the table section.

Let's skip the row and go right to the section box when painting the cells.

• layout/displaytree/DisplayPainter.cpp:

(WebCore::Display::absoluteDisplayBox):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• layout/displaytree/DisplayPainter.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2020-06-28  Zalan Bujtas  <zalan@apple.com>
+
+        [LFC][Painting] Use the table section as the paint container for table cells
+        https://bugs.webkit.org/show_bug.cgi?id=213693
+
+        Reviewed by Antti Koivisto.
+
+        The cell's containing block is the table box (skipping both the row and the section),
+        but it's positioned relative to the table section.
+
+        Let's skip the row and go right to the section box when painting the cells.
+
+        * layout/displaytree/DisplayPainter.cpp:
+        (WebCore::Display::absoluteDisplayBox):
+
 2020-06-28  Alexey Shvayka  <shvaikalesh@gmail.com>
 

trunk/Source/WebCore/layout/displaytree/DisplayPainter.cpp

@@ -142 +142 @@
 }
 
-static Box absoluteDisplayBox(const Layout::LayoutState& layoutState, const Layout::Box& layoutBox)
+static Box absoluteDisplayBox(const Layout::LayoutState& layoutState, const Layout::Box& layoutBoxToPaint)
 {
     // Should never really happen but table code is way too incomplete.
-    if (!layoutState.hasDisplayBox(layoutBox))
+    if (!layoutState.hasDisplayBox(layoutBoxToPaint))
         return { };
-    if (is<Layout::InitialContainingBlock>(layoutBox))
-        return layoutState.displayBoxForLayoutBox(layoutBox);
-
-    auto absoluteBox = Box { layoutState.displayBoxForLayoutBox(layoutBox) };
-    for (auto* containingBlock = &layoutBox.containingBlock(); !is<Layout::InitialContainingBlock>(*containingBlock); containingBlock = &containingBlock->containingBlock())
-        absoluteBox.moveBy(layoutState.displayBoxForLayoutBox(*containingBlock).topLeft());
+    if (is<Layout::InitialContainingBlock>(layoutBoxToPaint))
+        return layoutState.displayBoxForLayoutBox(layoutBoxToPaint);
+
+    auto paintContainer = [&] (const auto& layoutBox) {
+        if (layoutBox.isTableCell()) {
+            // The table cell's containing block is the table box (skipping both the row and the section), but it's positioned relative to the table section.
+            // Let's skip the row and go right to the section box.
+            return &layoutBox.parent().parent();
+        }
+        return &layoutBox.containingBlock();
+    };
+    auto absoluteBox = Box { layoutState.displayBoxForLayoutBox(layoutBoxToPaint) };
+    for (auto* container = paintContainer(layoutBoxToPaint); !is<Layout::InitialContainingBlock>(container); container = paintContainer(*container))
+        absoluteBox.moveBy(layoutState.displayBoxForLayoutBox(*container).topLeft());
     return absoluteBox;
 }