Changeset 125306 in webkit

Timestamp:

Aug 10, 2012 11:42:38 AM (12 years ago)

Author:

allan.jensen@nokia.com

Message:

[Transforms] Hit test issue with large scale() transform
​https://bugs.webkit.org/show_bug.cgi?id=23170

Reviewed by Simon Fraser.

Source/WebCore:

By using normal rounding to determine the top-left corner of the
hit-tested rectangle, we end up offsetting the hit test by up to
half a pixel, once scaled to x60, this creates a 30px error.

Normal rounding is replaced with floored rounding which means the
hit-tested pixel will now always be the pixel containing the
point.

Test: fast/transforms/hit-test-large-scale.html

• rendering/HitTestResult.cpp:

(WebCore::HitTestPoint::HitTestPoint):
(WebCore::HitTestPoint::intersectsRect):
(WebCore::HitTestPoint::rectForPoint):

LayoutTests:

New test checking that we can hit the bottom-right part of an element with
a large scale transformation.

Modified test-input on perspective-clipped.html, since it was mathematically
0.1px inside the transformed target, but used to miss due to bad rounding.

• fast/transforms/hit-test-large-scale-expected.txt: Added.
• fast/transforms/hit-test-large-scale.html: Added.
• transforms/3d/hit-testing/perspective-clipped-expected.txt:
• transforms/3d/hit-testing/perspective-clipped.html:

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/transforms/hit-test-large-scale-expected.txt (added)
• LayoutTests/fast/transforms/hit-test-large-scale.html (added)
• LayoutTests/transforms/3d/hit-testing/perspective-clipped-expected.txt (modified) (1 diff)
• LayoutTests/transforms/3d/hit-testing/perspective-clipped.html (modified) (1 diff)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/HitTestResult.cpp (modified) (3 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2012-08-10  Allan Sandfeld Jensen  <allan.jensen@nokia.com>
+
+        [Transforms] Hit test issue with large scale() transform
+        https://bugs.webkit.org/show_bug.cgi?id=23170
+
+        Reviewed by Simon Fraser.
+
+        New test checking that we can hit the bottom-right part of an element with
+        a large scale transformation.
+
+        Modified test-input on perspective-clipped.html, since it was mathematically
+        0.1px inside the transformed target, but used to miss due to bad rounding.
+
+        * fast/transforms/hit-test-large-scale-expected.txt: Added.
+        * fast/transforms/hit-test-large-scale.html: Added.
+        * transforms/3d/hit-testing/perspective-clipped-expected.txt:
+        * transforms/3d/hit-testing/perspective-clipped.html:
+
 2012-08-10  Takashi Sakamoto  <tasak@google.com>
 

trunk/LayoutTests/transforms/3d/hit-testing/perspective-clipped-expected.txt

@@ -10 +10 @@
 Element at 370, 280 has id "bottomLayer": PASS
 Element at 35, 340 has id "backgroundLayer": PASS
-Element at 370, 340 has id "backgroundLayer": PASS
+Element at 371, 340 has id "backgroundLayer": PASS
 

trunk/LayoutTests/transforms/3d/hit-testing/perspective-clipped.html

@@ -80 +80 @@
         // Points within the axis-aligned bounding box of the bottom layer, but not actually on the layer itself
         { 'point': [35, 340], 'target' : 'backgroundLayer' },
-        { 'point': [370, 340], 'target' : 'backgroundLayer' },
+        { 'point': [371, 340], 'target' : 'backgroundLayer' },
       ];
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2012-08-10  Allan Sandfeld Jensen  <allan.jensen@nokia.com>
+
+        [Transforms] Hit test issue with large scale() transform
+        https://bugs.webkit.org/show_bug.cgi?id=23170
+
+        Reviewed by Simon Fraser.
+
+        By using normal rounding to determine the top-left corner of the
+        hit-tested rectangle, we end up offsetting the hit test by up to
+        half a pixel, once scaled to x60, this creates a 30px error.
+
+        Normal rounding is replaced with floored rounding which means the
+        hit-tested pixel will now always be the pixel containing the
+        point.
+
+        Test: fast/transforms/hit-test-large-scale.html
+
+        * rendering/HitTestResult.cpp:
+        (WebCore::HitTestPoint::HitTestPoint):
+        (WebCore::HitTestPoint::intersectsRect):
+        (WebCore::HitTestPoint::rectForPoint):
+
 2012-08-10  Florin Malita  <fmalita@chromium.org>
 

trunk/Source/WebCore/rendering/HitTestResult.cpp

@@ -68 +68 @@
 
 HitTestPoint::HitTestPoint(const FloatPoint& point)
-    : m_point(roundedLayoutPoint(point))
+    : m_point(flooredLayoutPoint(point))
     , m_boundingBox(rectForPoint(m_point, 0, 0, 0, 0))
     , m_transformedPoint(point)
@@ -84 +84 @@
     , m_isRectBased(true)
 {
-    m_point = roundedLayoutPoint(point);
+    m_point = flooredLayoutPoint(point);
     m_boundingBox = enclosingIntRect(quad.boundingBox());
     m_isRectilinear = quad.isRectilinear();
@@ -182 +182 @@
 IntRect HitTestPoint::rectForPoint(const LayoutPoint& point, unsigned topPadding, unsigned rightPadding, unsigned bottomPadding, unsigned leftPadding)
 {
-    IntPoint actualPoint(roundedIntPoint(point));
+    IntPoint actualPoint(flooredIntPoint(point));
     actualPoint -= IntSize(leftPadding, topPadding);