Attachment #91386 for bug #59540

View Details Raw Unified Return to Bug 59540

| Differences between



2011-04-27  Jon Lee  <jonlee@apple.com>

        Reviewed by NOBODY (OOPS!).

        REGRESSION: white overlay scrollbars on apple.com/startpage
        https://bugs.webkit.org/show_bug.cgi?id=59540
        <rdar://problem/9338653>

        Now we look at the document background in addition to the <body> element,
        and blend those colors in with the base background of the frame view to
        arrive at our aggregate color. This provides a better result to determine
        overlay scrollbar style.

        * page/Frame.cpp:
        (WebCore::Frame::getDocumentBackgroundColor): look up the colors on the html and body element, and properly composite them.
        * platform/graphics/Color.h: a short comment to note that blend() uses the Porter-Duff source-over equation

2011-04-27  Pavel Feldman  <pfeldman@google.com>

        Reviewed by Yury Semikhatsky.



    
Color Frame::getDocumentBackgroundColor() const
{
    // <https://bugs.webkit.org/show_bug.cgi?id=59540> We blend the background color of
    // the document and the body against the base background color of the frame view.
    // Background images are unfortunately impractical to include.
    // adopted here to get the style used to paint the root background.

    // Return invalid Color objects whenever there is insufficient information.
    // for whatever reason.
    if (!m_doc)
        return Color();

    Element* htmlElement = m_doc->documentElement();
    Element* bodyElement = m_doc->body();

    // start as invalid colors
    Color htmlBackgroundColor;
    Color bodyBackgroundColor;
    if (htmlElement && htmlElement->renderer())
        htmlBackgroundColor = htmlElement->renderer()->style()->visitedDependentColor(CSSPropertyBackgroundColor);
    if (bodyElement && bodyElement->renderer())
        bodyBackgroundColor = bodyElement->renderer()->style()->visitedDependentColor(CSSPropertyBackgroundColor);
    
    if (!bodyBackgroundColor.isValid()) {
        if (!htmlBackgroundColor.isValid())
            return Color();
        return view()->baseBackgroundColor().blend(htmlBackgroundColor);
    }
    
    if (!htmlBackgroundColor.isValid())
        return view()->baseBackgroundColor().blend(bodyBackgroundColor);
        return Color();
    
    // We take the aggregate of the base background color
    // the <html> background color, and the <body>
    // background color to find the document color. The
    // addition of the base background color is not
    // technically part of the document background, but it
    // otherwise poses problems when the aggregate is not
    // fully opaque.
    return view()->baseBackgroundColor().blend(htmlBackgroundColor).blend(bodyBackgroundColor);
}

void Frame::setPrinting(bool printing, const FloatSize& pageSize, float maximumShrinkRatio, AdjustViewSizeOrNot shouldAdjustViewSize)



    Color light() const;
    Color dark() const;

    // This is an implementation of Porter-Duff's "source-over" equation
    Color blend(const Color&) const;
    Color blendWithWhite() const;

- 

Return to Bug 59540

Lines 503-529 String Frame::matchLabelsAgainstElement(const Vector<String>& labels, Element* e a/Source/WebCore/page/Frame.cpp_sec1
- a/Source/WebCore/page/Frame.cpp -15 / +30 lines
503		503
504	Color Frame::getDocumentBackgroundColor() const	504	Color Frame::getDocumentBackgroundColor() const
505	{	505	{
506	// FIXME: This is a basic implementation adopted originally from WebFrame,	506	// <https://bugs.webkit.org/show_bug.cgi?id=59540> We blend the background color of
507	// but ultimately is wrong. Body painting propagates up to the document (see	507	// the document and the body against the base background color of the frame view.
508	// RenderBox::paintRootBoxDecorations()), so code from that method should be	508	// Background images are unfortunately impractical to include.
509	// adopted here to get the style used to paint the root background.
510		509
511	// Return invalid Color objects if we are not able to obtain the color	510	// Return invalid Color objects whenever there is insufficient information.
512	// for whatever reason.
513	if (!m_doc)	511	if (!m_doc)
514	return Color();	512	return Color();
		513
		514	Element* htmlElement = m_doc->documentElement();
		515	Element* bodyElement = m_doc->body();
		516
		517	// start as invalid colors
		518	Color htmlBackgroundColor;
		519	Color bodyBackgroundColor;
		520	if (htmlElement && htmlElement->renderer())
		521	htmlBackgroundColor = htmlElement->renderer()->style()->visitedDependentColor(CSSPropertyBackgroundColor);
		522	if (bodyElement && bodyElement->renderer())
		523	bodyBackgroundColor = bodyElement->renderer()->style()->visitedDependentColor(CSSPropertyBackgroundColor);
515		524
516	Element* rootElementToUse = m_doc->body();	525	if (!bodyBackgroundColor.isValid()) {
517	if (!rootElementToUse)	526	if (!htmlBackgroundColor.isValid())
518	rootElementToUse = m_doc->documentElement();	527	return Color();
519	if (!rootElementToUse)	528	return view()->baseBackgroundColor().blend(htmlBackgroundColor);
520	return Color();	529	}
521		530
522	RenderObject* renderer = rootElementToUse->renderer();	531	if (!htmlBackgroundColor.isValid())
523	if (!renderer)	532	return view()->baseBackgroundColor().blend(bodyBackgroundColor);
524	return Color();
525		533
526	return renderer->style()->visitedDependentColor(CSSPropertyBackgroundColor);	534	// We take the aggregate of the base background color
		535	// the <html> background color, and the <body>
		536	// background color to find the document color. The
		537	// addition of the base background color is not
		538	// technically part of the document background, but it
		539	// otherwise poses problems when the aggregate is not
		540	// fully opaque.
		541	return view()->baseBackgroundColor().blend(htmlBackgroundColor).blend(bodyBackgroundColor);
527	}	542	}
528		543
529	void Frame::setPrinting(bool printing, const FloatSize& pageSize, float maximumShrinkRatio, AdjustViewSizeOrNot shouldAdjustViewSize)	544	void Frame::setPrinting(bool printing, const FloatSize& pageSize, float maximumShrinkRatio, AdjustViewSizeOrNot shouldAdjustViewSize)

Lines 121-126 public: a/Source/WebCore/platform/graphics/Color.h_sec1
- a/Source/WebCore/platform/graphics/Color.h -1 / +1 lines
121	Color light() const;	121	Color light() const;
122	Color dark() const;	122	Color dark() const;
123		123
		124	// This is an implementation of Porter-Duff's "source-over" equation
124	Color blend(const Color&) const;	125	Color blend(const Color&) const;
125	Color blendWithWhite() const;	126	Color blendWithWhite() const;
126		127
127	-

Lines 1-3 a/Source/WebCore/ChangeLog_sec1
- a/Source/WebCore/ChangeLog +17 lines
		1	2011-04-27 Jon Lee <jonlee@apple.com>
		2
		3	Reviewed by NOBODY (OOPS!).
		4
		5	REGRESSION: white overlay scrollbars on apple.com/startpage
		6	https://bugs.webkit.org/show_bug.cgi?id=59540
		7	<rdar://problem/9338653>
		8
		9	Now we look at the document background in addition to the <body> element,
		10	and blend those colors in with the base background of the frame view to
		11	arrive at our aggregate color. This provides a better result to determine
		12	overlay scrollbar style.
		13
		14	* page/Frame.cpp:
		15	(WebCore::Frame::getDocumentBackgroundColor): look up the colors on the html and body element, and properly composite them.
		16	* platform/graphics/Color.h: a short comment to note that blend() uses the Porter-Duff source-over equation
		17
1	2011-04-27 Pavel Feldman <pfeldman@google.com>	18	2011-04-27 Pavel Feldman <pfeldman@google.com>
2		19
3	Reviewed by Yury Semikhatsky.	20	Reviewed by Yury Semikhatsky.