Changeset 57633 in webkit

Timestamp:

Apr 14, 2010 9:48:05 PM (14 years ago)

Author:

Simon Fraser

Message:

2010-04-14 Simon Fraser <Simon Fraser>

Reviewed by Dan Bernstein.

Repaint of fixed, transformed element is broken
​https://bugs.webkit.org/show_bug.cgi?id=37637

RenderBox::computeRectForRepaint() failed to set the 'fixed' flag correctly
for elements that had both fixed position and a transform. If the element has
a transform, 'fixed' should only remain true if the element itself is fixed
position.

Also cache style()->position() in a local variable for performance.

Test: fast/repaint/fixed-tranformed.html

• rendering/RenderBox.cpp: (WebCore::RenderBox::computeRectForRepaint):

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/repaint/fixed-tranformed.html (added)
• LayoutTests/platform/mac/fast/repaint/fixed-tranformed-expected.checksum (added)
• LayoutTests/platform/mac/fast/repaint/fixed-tranformed-expected.png (added)
• LayoutTests/platform/mac/fast/repaint/fixed-tranformed-expected.txt (added)
• WebCore/ChangeLog (modified) (1 diff)
• WebCore/rendering/RenderBox.cpp (modified) (2 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2010-04-14  Simon Fraser  <simon.fraser@apple.com>
+
+        Reviewed by Dan Bernstein.
+
+        Repaint of fixed, transformed element is broken
+        https://bugs.webkit.org/show_bug.cgi?id=37637
+
+        Testcase for repainting a fixed-position elemnt with a transform in a
+        scrolled page.
+        
+        * fast/repaint/fixed-tranformed.html: Added.
+        * platform/mac/fast/repaint/fixed-tranformed-expected.checksum: Added.
+        * platform/mac/fast/repaint/fixed-tranformed-expected.png: Added.
+        * platform/mac/fast/repaint/fixed-tranformed-expected.txt: Added.
+
 2010-04-14  Luiz Agostini  <luiz.agostini@openbossa.org>
 

trunk/WebCore/ChangeLog

@@ +1 @@
+2010-04-14  Simon Fraser  <simon.fraser@apple.com>
+
+        Reviewed by Dan Bernstein.
+
+        Repaint of fixed, transformed element is broken
+        https://bugs.webkit.org/show_bug.cgi?id=37637
+
+        RenderBox::computeRectForRepaint() failed to set the 'fixed' flag correctly
+        for elements that had both fixed position and a transform. If the element has
+        a transform, 'fixed' should only remain true if the element itself is fixed
+        position.
+        
+        Also cache style()->position() in a local variable for performance.
+        
+        Test: fast/repaint/fixed-tranformed.html
+
+        * rendering/RenderBox.cpp:
+        (WebCore::RenderBox::computeRectForRepaint):
+
 2010-04-14  Luiz Agostini  <luiz.agostini@openbossa.org>
 

trunk/WebCore/rendering/RenderBox.cpp

@@ -1185 +1185 @@
     topLeft.move(x(), y());
 
-    if (style()->position() == FixedPosition)
-        fixed = true;
-
-    if (o->isBlockFlow() && style()->position() != AbsolutePosition && style()->position() != FixedPosition) {
+    EPosition position = style()->position();
+
+    if (o->isBlockFlow() && position != AbsolutePosition && position != FixedPosition) {
         RenderBlock* cb = toRenderBlock(o);
         if (cb->hasColumns()) {
@@ -1201 +1200 @@
     // in the parent's coordinate space that encloses us.
     if (layer() && layer()->transform()) {
-        fixed = false;
+        fixed = position == FixedPosition;
         rect = layer()->transform()->mapRect(rect);
         // FIXME: this clobbers topLeft adjustment done for multicol above
         topLeft = rect.location();
         topLeft.move(x(), y());
-    }
-
-    if (style()->position() == AbsolutePosition && o->isRelPositioned() && o->isRenderInline())
+    } else if (position == FixedPosition)
+        fixed = true;
+
+    if (position == AbsolutePosition && o->isRelPositioned() && o->isRenderInline())
         topLeft += toRenderInline(o)->relativePositionedInlineOffset(this);
-    else if (style()->position() == RelativePosition && layer()) {
+    else if (position == RelativePosition && layer()) {
         // Apply the relative position offset when invalidating a rectangle.  The layer
         // is translated, but the render box isn't, so we need to do this to get the