Fix pointer-events:all when stroke="none"

Source/core/layout/svg/LayoutSVGRect.cpp

 /*
  * Copyright (C) 2011 University of Szeged
  * Copyright (C) 2011 Renata Hodovan <reni@webkit.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 11 matching lines @@
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/layout/svg/LayoutSVGRect.h"
 
 #include "core/svg/SVGRectElement.h"
+#include "wtf/MathExtras.h"
 
 namespace blink {
 
 LayoutSVGRect::LayoutSVGRect(SVGRectElement* node)
     : LayoutSVGShape(node)
     , m_usePathFallback(false)
 {
 }
 
 LayoutSVGRect::~LayoutSVGRect()
 {
 }
 
 void LayoutSVGRect::updateShapeFromElement()
 {
     // Before creating a new object we need to clear the cached bounding box
     // to avoid using garbage.
     m_fillBoundingBox = FloatRect();
-    m_innerStrokeRect = FloatRect();
-    m_outerStrokeRect = FloatRect();
+    m_strokeBoundingBox = FloatRect();
     m_usePathFallback = false;
     SVGRectElement* rect = toSVGRectElement(element());
     ASSERT(rect);
 
     SVGLengthContext lengthContext(rect);
     FloatSize boundingBoxSize(
         lengthContext.valueForLength(styleRef().width(), styleRef(), SVGLengthMode::Width),
         lengthContext.valueForLength(styleRef().height(), styleRef(), SVGLengthMode::Height));
 
     // Spec: "A negative value is an error."
@@ skipping 12 matching lines @@
             m_usePathFallback = true;
             return;
         }
     }
 
     m_fillBoundingBox = FloatRect(
         FloatPoint(
             lengthContext.valueForLength(styleRef().svgStyle().x(), styleRef(), SVGLengthMode::Width),
             lengthContext.valueForLength(styleRef().svgStyle().y(), styleRef(), SVGLengthMode::Height)),
         boundingBoxSize);
-
-    // To decide if the stroke contains a point we create two rects which represent the inner and
-    // the outer stroke borders. A stroke contains the point, if the point is between them.
-    m_innerStrokeRect = m_fillBoundingBox;
-    m_outerStrokeRect = m_fillBoundingBox;
-
-    if (style()->svgStyle().hasStroke()) {
-        float strokeWidth = this->strokeWidth();
-        m_innerStrokeRect.inflate(-strokeWidth / 2);
-        m_outerStrokeRect.inflate(strokeWidth / 2);
-    }
-
-    m_strokeBoundingBox = m_outerStrokeRect;
+    m_strokeBoundingBox = m_fillBoundingBox;
+    if (style()->svgStyle().hasStroke())
+        m_strokeBoundingBox.inflate(strokeWidth() / 2);
 }
 
 bool LayoutSVGRect::shapeDependentStrokeContains(const FloatPoint& point)
 {
     // The optimized code below does not support non-simple strokes so we need
     // to fall back to LayoutSVGShape::shapeDependentStrokeContains in these cases.
     if (m_usePathFallback || !definitelyHasSimpleStroke()) {
         if (!hasPath())
             LayoutSVGShape::updateShapeFromElement();
         return LayoutSVGShape::shapeDependentStrokeContains(point);
     }
 
-    return m_outerStrokeRect.contains(point, FloatRect::InsideOrOnStroke) && !m_innerStrokeRect.contains(point, FloatRect::InsideButNotOnStroke);
+    const float halfStrokeWidth = strokeWidth() / 2;
+    const float halfWidth = m_fillBoundingBox.width() / 2;
+    const float halfHeight = m_fillBoundingBox.height() / 2;
+
+    const FloatPoint fillBoundingBoxCenter = FloatPoint(m_fillBoundingBox.x() + halfWidth, m_fillBoundingBox.y() + halfHeight);
+    const float absDeltaX = std::abs(point.x() - fillBoundingBoxCenter.x());
+    const float absDeltaY = std::abs(point.y() - fillBoundingBoxCenter.y());
+
+    if (!(absDeltaX <= halfWidth + halfStrokeWidth && absDeltaY <= halfHeight + halfStrokeWidth))
+        return false;
+
+    return (halfWidth - halfStrokeWidth <= absDeltaX)
+        || (halfHeight - halfStrokeWidth <= absDeltaY);
 }
 
 bool LayoutSVGRect::shapeDependentFillContains(const FloatPoint& point, const WindRule fillRule) const
 {
     if (m_usePathFallback)
         return LayoutSVGShape::shapeDependentFillContains(point, fillRule);
     return m_fillBoundingBox.contains(point.x(), point.y());
 }
 
 // Returns true if the stroke is continuous and definitely uses miter joins.
@@ skipping 16 matching lines @@
     // An approximation of sqrt(2) is used here because at certain precise
     // miterlimits, the join style used might not be correct (e.g. a miterlimit
     // of 1.4142135 should result in bevel joins, but may be drawn using miter
     // joins).
     return svgStyle.strokeDashArray()->isEmpty()
         && svgStyle.joinStyle() == MiterJoin
         && svgStyle.strokeMiterLimit() >= 1.5;
 }
 
 }