root/Source/core/rendering/RenderRegion.cpp

DEFINITIONS

1. m_isValid
2. pageLogicalWidth
3. pageLogicalHeight
4. logicalHeightOfAllFlowThreadContent
5. flowThreadPortionOverflowRect
6. overflowRectForFlowThreadPortion
7. pageLogicalTopForOffset
8. isFirstRegion
9. isLastRegion
10. layoutBlock
11. repaintFlowThreadContent
12. repaintFlowThreadContentRectangle
13. attachRegion
14. detachRegion
15. logicalTopOfFlowThreadContentRect
16. logicalBottomOfFlowThreadContentRect
17. insertedIntoTree
18. willBeRemovedFromTree
19. computeIntrinsicLogicalWidths

/*
 * Copyright (C) 2011 Adobe Systems Incorporated. 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.
 * 2. Redistributions in binary form must reproduce the above
 *    copyright notice, this list of conditions and the following
 *    disclaimer in the documentation and/or other materials
 *    provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * 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/rendering/RenderRegion.h"

#include "core/css/resolver/StyleResolver.h"
#include "core/rendering/FlowThreadController.h"
#include "core/rendering/HitTestLocation.h"
#include "core/rendering/PaintInfo.h"
#include "core/rendering/RenderFlowThread.h"
#include "core/rendering/RenderView.h"

using namespace std;

namespace WebCore {

RenderRegion::RenderRegion(Element* element, RenderFlowThread* flowThread)
    : RenderBlockFlow(element)
    , m_flowThread(flowThread)
    , m_isValid(false)
{
}

LayoutUnit RenderRegion::pageLogicalWidth() const
{
    ASSERT(m_flowThread);
    return m_flowThread->isHorizontalWritingMode() ? contentWidth() : contentHeight();
}

LayoutUnit RenderRegion::pageLogicalHeight() const
{
    ASSERT(m_flowThread);
    return m_flowThread->isHorizontalWritingMode() ? contentHeight() : contentWidth();
}

LayoutUnit RenderRegion::logicalHeightOfAllFlowThreadContent() const
{
    ASSERT(m_flowThread);
    return m_flowThread->isHorizontalWritingMode() ? contentHeight() : contentWidth();
}

LayoutRect RenderRegion::flowThreadPortionOverflowRect() const
{
    return overflowRectForFlowThreadPortion(flowThreadPortionRect(), isFirstRegion(), isLastRegion());
}

LayoutRect RenderRegion::overflowRectForFlowThreadPortion(const LayoutRect& flowThreadPortionRect, bool isFirstPortion, bool isLastPortion) const
{
    ASSERT(isValid());

    if (hasOverflowClip())
        return flowThreadPortionRect;

    LayoutRect flowThreadOverflow = m_flowThread->visualOverflowRect();

    // Only clip along the flow thread axis.
    LayoutRect clipRect;
    if (m_flowThread->isHorizontalWritingMode()) {
        LayoutUnit minY = isFirstPortion ? flowThreadOverflow.y() : flowThreadPortionRect.y();
        LayoutUnit maxY = isLastPortion ? max(flowThreadPortionRect.maxY(), flowThreadOverflow.maxY()) : flowThreadPortionRect.maxY();
        LayoutUnit minX = min(flowThreadPortionRect.x(), flowThreadOverflow.x());
        LayoutUnit maxX = max(flowThreadPortionRect.maxX(), flowThreadOverflow.maxX());
        clipRect = LayoutRect(minX, minY, maxX - minX, maxY - minY);
    } else {
        LayoutUnit minX = isFirstPortion ? flowThreadOverflow.x() : flowThreadPortionRect.x();
        LayoutUnit maxX = isLastPortion ? max(flowThreadPortionRect.maxX(), flowThreadOverflow.maxX()) : flowThreadPortionRect.maxX();
        LayoutUnit minY = min(flowThreadPortionRect.y(), (flowThreadOverflow.y()));
        LayoutUnit maxY = max(flowThreadPortionRect.y(), (flowThreadOverflow.maxY()));
        clipRect = LayoutRect(minX, minY, maxX - minX, maxY - minY);
    }

    return clipRect;
}

LayoutUnit RenderRegion::pageLogicalTopForOffset(LayoutUnit /* offset */) const
{
    return flowThread()->isHorizontalWritingMode() ? flowThreadPortionRect().y() : flowThreadPortionRect().x();
}

bool RenderRegion::isFirstRegion() const
{
    ASSERT(isValid());

    return m_flowThread->firstRegion() == this;
}

bool RenderRegion::isLastRegion() const
{
    ASSERT(isValid());

    return m_flowThread->lastRegion() == this;
}

void RenderRegion::layoutBlock(bool relayoutChildren)
{
    RenderBlockFlow::layoutBlock(relayoutChildren);

    // FIXME: We need to find a way to set up overflow properly. Our flow thread hasn't gotten a layout
    // yet, so we can't look to it for correct information. It's possible we could wait until after the RenderFlowThread
    // gets a layout, and then try to propagate overflow information back to the region, and then mark for a second layout.
    // That second layout would then be able to use the information from the RenderFlowThread to set up overflow.
    //
    // The big problem though is that overflow needs to be region-specific. We can't simply use the RenderFlowThread's global
    // overflow values, since then we'd always think any narrow region had huge overflow (all the way to the width of the
    // RenderFlowThread itself).
}

void RenderRegion::repaintFlowThreadContent(const LayoutRect& repaintRect) const
{
    repaintFlowThreadContentRectangle(repaintRect, flowThreadPortionRect(), flowThreadPortionOverflowRect(), contentBoxRect().location());
}

void RenderRegion::repaintFlowThreadContentRectangle(const LayoutRect& repaintRect, const LayoutRect& flowThreadPortionRect, const LayoutRect& flowThreadPortionOverflowRect, const LayoutPoint& regionLocation) const
{
    ASSERT(isValid());

    // We only have to issue a repaint in this region if the region rect intersects the repaint rect.
    LayoutRect flippedFlowThreadPortionRect(flowThreadPortionRect);
    LayoutRect flippedFlowThreadPortionOverflowRect(flowThreadPortionOverflowRect);
    flowThread()->flipForWritingMode(flippedFlowThreadPortionRect); // Put the region rects into physical coordinates.
    flowThread()->flipForWritingMode(flippedFlowThreadPortionOverflowRect);

    LayoutRect clippedRect(repaintRect);
    clippedRect.intersect(flippedFlowThreadPortionOverflowRect);
    if (clippedRect.isEmpty())
        return;

    // Put the region rect into the region's physical coordinate space.
    clippedRect.setLocation(regionLocation + (clippedRect.location() - flippedFlowThreadPortionRect.location()));

    // Now switch to the region's writing mode coordinate space and let it repaint itself.
    flipForWritingMode(clippedRect);

    // Issue the repaint.
    repaintRectangle(clippedRect);
}

void RenderRegion::attachRegion()
{
    if (documentBeingDestroyed())
        return;

    // A region starts off invalid.
    setIsValid(false);

    if (!m_flowThread)
        return;

    // Only after adding the region to the thread, the region is marked to be valid.
    m_flowThread->addRegionToThread(this);
}

void RenderRegion::detachRegion()
{
    if (m_flowThread) {
        m_flowThread->removeRegionFromThread(this);
        m_flowThread = 0;
    }
}

LayoutUnit RenderRegion::logicalTopOfFlowThreadContentRect(const LayoutRect& rect) const
{
    ASSERT(isValid());
    return flowThread()->isHorizontalWritingMode() ? rect.y() : rect.x();
}

LayoutUnit RenderRegion::logicalBottomOfFlowThreadContentRect(const LayoutRect& rect) const
{
    ASSERT(isValid());
    return flowThread()->isHorizontalWritingMode() ? rect.maxY() : rect.maxX();
}

void RenderRegion::insertedIntoTree()
{
    RenderBlockFlow::insertedIntoTree();

    attachRegion();
}

void RenderRegion::willBeRemovedFromTree()
{
    RenderBlockFlow::willBeRemovedFromTree();

    detachRegion();
}

void RenderRegion::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const
{
    if (!isValid()) {
        RenderBlockFlow::computeIntrinsicLogicalWidths(minLogicalWidth, maxLogicalWidth);
        return;
    }

    minLogicalWidth = m_flowThread->minPreferredLogicalWidth();
    maxLogicalWidth = m_flowThread->maxPreferredLogicalWidth();
}

} // namespace WebCore