Changeset 138036 in webkit

Timestamp:

Dec 18, 2012, 10:07:56 AM (12 years ago)

Author:

Simon Fraser

Message:

Fix position:-webkit-sticky behavior when zoomed
​https://bugs.webkit.org/show_bug.cgi?id=105251

Reviewed by Dean Jackson.

Source/WebCore:

Position sticky elements were misplaced when stickily-constrained, under zooming.
The cause was that some of the functions used to compute sticky position
took page scale into account, and some did not.

Fix by using localToContainerQuad(..., view()) to compute RenderView-relative
quads, which avoids page scale, so all the constraints math is done ignoring
page scale. This also requires that we compute a scale-free viewport rect
in stickyPositionOffset().

Test: fast/css/sticky/sticky-top-zoomed.html

• rendering/RenderBoxModelObject.cpp:

(WebCore::RenderBoxModelObject::computeStickyPositionConstraints):
(WebCore::RenderBoxModelObject::stickyPositionOffset):

LayoutTests:

Ref test for sticky elements in a zoomed page.

This test is marked as failing for WK1, because scrollbars always show on
zoomed pages and cannot be hidden there.

• fast/css/sticky/sticky-top-zoomed-expected.html: Added.
• fast/css/sticky/sticky-top-zoomed.html: Added.
• platform/mac-wk2/TestExpectations:
• platform/mac/TestExpectations:

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/css/sticky/sticky-top-zoomed-expected.html (added)
• LayoutTests/fast/css/sticky/sticky-top-zoomed.html (added)
• LayoutTests/platform/mac-wk2/TestExpectations (modified) (1 diff)
• LayoutTests/platform/mac/TestExpectations (modified) (1 diff)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/RenderBoxModelObject.cpp (modified) (3 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2012-12-17  Simon Fraser  <simon.fraser@apple.com>
+
+        Fix position:-webkit-sticky behavior when zoomed
+        https://bugs.webkit.org/show_bug.cgi?id=105251
+
+        Reviewed by Dean Jackson.
+
+        Ref test for sticky elements in a zoomed page.
+        
+        This test is marked as failing for WK1, because scrollbars always show on
+        zoomed pages and cannot be hidden there.
+
+        * fast/css/sticky/sticky-top-zoomed-expected.html: Added.
+        * fast/css/sticky/sticky-top-zoomed.html: Added.
+        * platform/mac-wk2/TestExpectations:
+        * platform/mac/TestExpectations:
+
 2012-12-18  Thiago Marcos P. Santos  <thiago.santos@intel.com>
 

trunk/LayoutTests/platform/mac-wk2/TestExpectations

@@ -363 +363 @@
 
 platform/mac/tiled-drawing/ [ Pass ]
+fast/css/sticky/sticky-top-zoomed.html [ Pass ]
 
 ### END OF (5) Features that are not supported in WebKit1, so skipped in mac/TestExpectations then re-enabled here

trunk/LayoutTests/platform/mac/TestExpectations

@@ -1217 +1217 @@
 platform/mac/tiled-drawing/ [ Skip ]
 
+# Can't hide scrollbars in WK1
+fast/css/sticky/sticky-top-zoomed.html [ ImageOnlyFailure ]
+
 webkit.org/b/100846 inspector-protocol/debugger-pause-dedicated-worker.html [ Skip ]
 webkit.org/b/100846 inspector-protocol/debugger-terminate-dedicated-worker-while-paused.html [ Skip ]

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2012-12-17  Simon Fraser  <simon.fraser@apple.com>
+
+        Fix position:-webkit-sticky behavior when zoomed
+        https://bugs.webkit.org/show_bug.cgi?id=105251
+
+        Reviewed by Dean Jackson.
+
+        Position sticky elements were misplaced when stickily-constrained, under zooming.
+        The cause was that some of the functions used to compute sticky position
+        took page scale into account, and some did not.
+        
+        Fix by using localToContainerQuad(..., view()) to compute RenderView-relative
+        quads, which avoids page scale, so all the constraints math is done ignoring
+        page scale. This also requires that we compute a scale-free viewport rect
+        in stickyPositionOffset().
+
+        Test: fast/css/sticky/sticky-top-zoomed.html
+
+        * rendering/RenderBoxModelObject.cpp:
+        (WebCore::RenderBoxModelObject::computeStickyPositionConstraints):
+        (WebCore::RenderBoxModelObject::stickyPositionOffset):
+
 2012-12-18  Eugene Klyuchnikov  <eustas@chromium.org>
 

trunk/Source/WebCore/rendering/RenderBoxModelObject.cpp

@@ -472 +472 @@
     containerContentRect.move(minLeftMargin, minTopMargin);
     containerContentRect.contract(minLeftMargin + minRightMargin, minTopMargin + minBottomMargin);
-    constraints.setAbsoluteContainingBlockRect(containingBlock->localToAbsoluteQuad(FloatRect(containerContentRect)).boundingBox());
+    // Map to the view to avoid including page scale factor.
+    constraints.setAbsoluteContainingBlockRect(containingBlock->localToContainerQuad(FloatRect(containerContentRect), view()).boundingBox());
 
     LayoutRect stickyBoxRect = frameRectForStickyPositioning();
@@ -480 +481 @@
 
     // FIXME: sucks to call localToAbsolute again, but we can't just offset from the previously computed rect if there are transforms.
-    FloatRect absContainerFrame = containingBlock->localToAbsoluteQuad(FloatRect(FloatPoint(), containingBlock->size())).boundingBox();
+    // Map to the view to avoid including page scale factor.
+    FloatRect absContainerFrame = containingBlock->localToContainerQuad(FloatRect(FloatPoint(), containingBlock->size()), view()).boundingBox();
+
     // We can't call localToAbsolute on |this| because that will recur. FIXME: For now, assume that |this| is not transformed.
     FloatRect absoluteStickyBoxRect(absContainerFrame.location() + stickyLocation, flippedStickyBoxRect.size());
@@ -509 +512 @@
 {
     LayoutRect viewportRect = view()->frameView()->visibleContentRect();
-
+    float scale = 1;
+    if (Frame* frame = view()->frameView()->frame())
+        scale = frame->frameScaleFactor();
+    
+    viewportRect.scale(1 / scale);
+    
     StickyPositionViewportConstraints constraints;
     computeStickyPositionConstraints(constraints, viewportRect);