Changeset 219742 in webkit

Timestamp:

Jul 21, 2017 2:04:43 PM (7 years ago)

Author:

Alan Bujtas

Message:

iBooks: Overlapping/missing content at beginning/end of paragraph.
​https://bugs.webkit.org/show_bug.cgi?id=174717
<rdar://problem/33117912>

Reviewed by Simon Fraser.

By definiton simple and normal line layout should always produce the exact same lineboxes. It enables us not
to force repaint while swapping between these 2 line layouts.
However in certain cases (font size pixel rounding as an example) they don't agree on how much content fits the line and
that could result in missing/overlapping content due to the lack of repaint.

Unable to test.

• rendering/RenderBlockFlow.cpp:

(WebCore::RenderBlockFlow::ensureLineBoxes):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• rendering/RenderBlockFlow.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2017-07-21  Zalan Bujtas  <zalan@apple.com>
+
+        iBooks: Overlapping/missing content at beginning/end of paragraph.
+        https://bugs.webkit.org/show_bug.cgi?id=174717
+        <rdar://problem/33117912>
+
+        Reviewed by Simon Fraser.
+
+        By definiton simple and normal line layout should always produce the exact same lineboxes. It enables us not
+        to force repaint while swapping between these 2 line layouts.
+        However in certain cases (font size pixel rounding as an example) they don't agree on how much content fits the line and
+        that could result in missing/overlapping content due to the lack of repaint. 
+
+        Unable to test.
+
+        * rendering/RenderBlockFlow.cpp:
+        (WebCore::RenderBlockFlow::ensureLineBoxes):
+
 2017-07-21  Chris Dumez  <cdumez@apple.com>
 

trunk/Source/WebCore/rendering/RenderBlockFlow.cpp

@@ -3759 +3759 @@
         if (shouldBreakAtLineToAvoidWidow())
             layoutLineBoxes(relayoutChildren, repaintLogicalTop, repaintLogicalBottom);
+        // FIXME: This is needed as long as simple and normal line layout produce different line breakings.
+        repaint();
     } else
         layoutLineBoxes(relayoutChildren, repaintLogicalTop, repaintLogicalBottom);