RenderReplaced.cpp   [plain text]

 * Copyright (C) 1999 Lars Knoll (
 * Copyright (C) 2000 Dirk Mueller (
 * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
 * Copyright (C) Research In Motion Limited 2011-2012. All rights reserved.
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * Library General Public License for more details.
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.

#include "config.h"
#include "RenderReplaced.h"

#include "Frame.h"
#include "GraphicsContext.h"
#include "LayoutRepainter.h"
#include "Page.h"
#include "RenderBlock.h"
#include "RenderLayer.h"
#include "RenderTheme.h"
#include "RenderView.h"
#include "VisiblePosition.h"
#include <wtf/StackStats.h>

using namespace std;

namespace WebCore {

const int cDefaultWidth = 300;
const int cDefaultHeight = 150;

RenderReplaced::RenderReplaced(Element* element)
    : RenderBox(element)
    , m_intrinsicSize(cDefaultWidth, cDefaultHeight)

RenderReplaced::RenderReplaced(Element* element, const LayoutSize& intrinsicSize)
    : RenderBox(element)
    , m_intrinsicSize(intrinsicSize)


void RenderReplaced::willBeDestroyed()
    if (!documentBeingDestroyed() && parent())


void RenderReplaced::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
    RenderBox::styleDidChange(diff, oldStyle);

    bool hadStyle = (oldStyle != 0);
    float oldZoom = hadStyle ? oldStyle->effectiveZoom() : RenderStyle::initialZoom();
    if (style() && style()->effectiveZoom() != oldZoom)

void RenderReplaced::layout()
    StackStats::LayoutCheckPoint layoutCheckPoint;
    LayoutRepainter repainter(*this, checkForRepaintDuringLayout());




void RenderReplaced::intrinsicSizeChanged()
    int scaledWidth = static_cast<int>(cDefaultWidth * style()->effectiveZoom());
    int scaledHeight = static_cast<int>(cDefaultHeight * style()->effectiveZoom());
    m_intrinsicSize = IntSize(scaledWidth, scaledHeight);

void RenderReplaced::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
    if (!shouldPaint(paintInfo, paintOffset))
    LayoutPoint adjustedPaintOffset = paintOffset + location();
    if (hasBoxDecorations() && (paintInfo.phase == PaintPhaseForeground || paintInfo.phase == PaintPhaseSelection)) 
        paintBoxDecorations(paintInfo, adjustedPaintOffset);
    if (paintInfo.phase == PaintPhaseMask) {
        paintMask(paintInfo, adjustedPaintOffset);

    LayoutRect paintRect = LayoutRect(adjustedPaintOffset, size());
    if ((paintInfo.phase == PaintPhaseOutline || paintInfo.phase == PaintPhaseSelfOutline) && style()->outlineWidth())
        paintOutline(paintInfo.context, paintRect);
    if (paintInfo.phase != PaintPhaseForeground && paintInfo.phase != PaintPhaseSelection && !canHaveChildren())
    if (!paintInfo.shouldPaintWithinRoot(this))
    bool drawSelectionTint = selectionState() != SelectionNone && !document()->printing();
    if (paintInfo.phase == PaintPhaseSelection) {
        if (selectionState() == SelectionNone)
        drawSelectionTint = false;

    bool completelyClippedOut = false;
    if (style()->hasBorderRadius()) {
        LayoutRect borderRect = LayoutRect(adjustedPaintOffset, size());

        if (borderRect.isEmpty())
            completelyClippedOut = true;
        else {
            // Push a clip if we have a border radius, since we want to round the foreground content that gets painted.
            RoundedRect roundedInnerRect = style()->getRoundedInnerBorderFor(paintRect,
                paddingTop() + borderTop(), paddingBottom() + borderBottom(), paddingLeft() + borderLeft(), paddingRight() + borderRight(), true, true);
            clipRoundedInnerRect(paintInfo.context, paintRect, roundedInnerRect);

    if (!completelyClippedOut) {
        paintReplaced(paintInfo, adjustedPaintOffset);

        if (style()->hasBorderRadius())
    // The selection tint never gets clipped by border-radius rounding, since we want it to run right up to the edges of
    // surrounding content.
    if (drawSelectionTint) {
        LayoutRect selectionPaintingRect = localSelectionRect();
        paintInfo.context->fillRect(pixelSnappedIntRect(selectionPaintingRect), selectionBackgroundColor(), style()->colorSpace());

bool RenderReplaced::shouldPaint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
    if (paintInfo.phase != PaintPhaseForeground && paintInfo.phase != PaintPhaseOutline && paintInfo.phase != PaintPhaseSelfOutline 
            && paintInfo.phase != PaintPhaseSelection && paintInfo.phase != PaintPhaseMask)
        return false;

    if (!paintInfo.shouldPaintWithinRoot(this))
        return false;
    // if we're invisible or haven't received a layout yet, then just bail.
    if (style()->visibility() != VISIBLE)
        return false;

    LayoutPoint adjustedPaintOffset = paintOffset + location();

    // Early exit if the element touches the edges.
    LayoutUnit top = adjustedPaintOffset.y() + visualOverflowRect().y();
    LayoutUnit bottom = adjustedPaintOffset.y() + visualOverflowRect().maxY();
    if (isSelected() && m_inlineBoxWrapper) {
        LayoutUnit selTop = paintOffset.y() + m_inlineBoxWrapper->root()->selectionTop();
        LayoutUnit selBottom = paintOffset.y() + selTop + m_inlineBoxWrapper->root()->selectionHeight();
        top = min(selTop, top);
        bottom = max(selBottom, bottom);
    LayoutRect localRepaintRect = paintInfo.rect;
    if (adjustedPaintOffset.x() + visualOverflowRect().x() >= localRepaintRect.maxX() || adjustedPaintOffset.x() + visualOverflowRect().maxX() <= localRepaintRect.x())
        return false;

    if (top >= localRepaintRect.maxY() || bottom <= localRepaintRect.y())
        return false;

    return true;

static inline RenderBlock* firstContainingBlockWithLogicalWidth(const RenderReplaced* replaced)
    // We have to lookup the containing block, which has an explicit width, which must not be equal to our direct containing block.
    // If the embedded document appears _after_ we performed the initial layout, our intrinsic size is 300x150. If our containing
    // block doesn't provide an explicit width, it's set to the 300 default, coming from the initial layout run.
    RenderBlock* containingBlock = replaced->containingBlock();
    if (!containingBlock)
        return 0;

    for (; !containingBlock->isRenderView() && !containingBlock->isBody(); containingBlock = containingBlock->containingBlock()) {
        if (containingBlock->style()->logicalWidth().isSpecified())
            return containingBlock;

    return 0;

bool RenderReplaced::hasReplacedLogicalWidth() const
    if (style()->logicalWidth().isSpecified())
        return true;

    if (style()->logicalWidth().isAuto())
        return false;

    return firstContainingBlockWithLogicalWidth(this);

bool RenderReplaced::hasReplacedLogicalHeight() const
    if (style()->logicalHeight().isAuto())
        return false;

    if (style()->logicalHeight().isSpecified()) {
        if (hasAutoHeightOrContainingBlockWithAutoHeight())
            return false;
        return true;

    return false;

void RenderReplaced::computeAspectRatioInformationForRenderBox(RenderBox* contentRenderer, FloatSize& constrainedSize, double& intrinsicRatio, bool& isPercentageIntrinsicSize) const
    FloatSize intrinsicSize;
    if (contentRenderer) {
        contentRenderer->computeIntrinsicRatioInformation(intrinsicSize, intrinsicRatio, isPercentageIntrinsicSize);
        if (intrinsicRatio)

        // Handle zoom & vertical writing modes here, as the embedded document doesn't know about them.
        if (!isPercentageIntrinsicSize)

        if (hasAspectRatio() && isPercentageIntrinsicSize)
            intrinsicRatio = 1;
        // Update our intrinsic size to match what the content renderer has computed, so that when we
        // constrain the size below, the correct intrinsic size will be obtained for comparison against
        // min and max widths.
        if (intrinsicRatio && !isPercentageIntrinsicSize && !intrinsicSize.isEmpty())
            m_intrinsicSize = LayoutSize(intrinsicSize);

        if (!isHorizontalWritingMode()) {
            if (intrinsicRatio)
                intrinsicRatio = 1 / intrinsicRatio;
            intrinsicSize = intrinsicSize.transposedSize();
    } else {
        computeIntrinsicRatioInformation(intrinsicSize, intrinsicRatio, isPercentageIntrinsicSize);
        if (intrinsicRatio) {
            if (!intrinsicSize.isEmpty())
                m_intrinsicSize = LayoutSize(isHorizontalWritingMode() ? intrinsicSize : intrinsicSize.transposedSize());

    // Now constrain the intrinsic size along each axis according to minimum and maximum width/heights along the
    // opposite axis. So for example a maximum width that shrinks our width will result in the height we compute here
    // having to shrink in order to preserve the aspect ratio. Because we compute these values independently along
    // each axis, the final returned size may in fact not preserve the aspect ratio.
    // FIXME: In the long term, it might be better to just return this code more to the way it used to be before this
    // function was added, since all it has done is make the code more unclear.
    constrainedSize = intrinsicSize;
    if (intrinsicRatio && !isPercentageIntrinsicSize && !intrinsicSize.isEmpty() && style()->logicalWidth().isAuto() && style()->logicalHeight().isAuto()) {
        // We can't multiply or divide by 'intrinsicRatio' here, it breaks tests, like fast/images/zoomed-img-size.html, which
        // can only be fixed once subpixel precision is available for things like intrinsicWidth/Height - which include zoom!
        constrainedSize.setWidth(RenderBox::computeReplacedLogicalHeight() * intrinsicSize.width() / intrinsicSize.height());
        constrainedSize.setHeight(RenderBox::computeReplacedLogicalWidth() * intrinsicSize.height() / intrinsicSize.width());

void RenderReplaced::computeIntrinsicRatioInformation(FloatSize& intrinsicSize, double& intrinsicRatio, bool& isPercentageIntrinsicSize) const
    // If there's an embeddedContentBox() of a remote, referenced document available, this code-path should never be used.
    isPercentageIntrinsicSize = false;
    intrinsicSize = FloatSize(intrinsicLogicalWidth(), intrinsicLogicalHeight());

    // Figure out if we need to compute an intrinsic ratio.
    if (intrinsicSize.isEmpty() || !hasAspectRatio())

    intrinsicRatio = intrinsicSize.width() / intrinsicSize.height();

LayoutUnit RenderReplaced::computeReplacedLogicalWidth(ShouldComputePreferred shouldComputePreferred) const
    if (style()->logicalWidth().isSpecified() || style()->logicalWidth().isIntrinsic())
        return computeReplacedLogicalWidthRespectingMinMaxWidth(computeReplacedLogicalWidthUsing(style()->logicalWidth()), shouldComputePreferred);

    RenderBox* contentRenderer = embeddedContentBox();

    // 10.3.2 Inline, replaced elements:
    bool isPercentageIntrinsicSize = false;
    double intrinsicRatio = 0;
    FloatSize constrainedSize;
    computeAspectRatioInformationForRenderBox(contentRenderer, constrainedSize, intrinsicRatio, isPercentageIntrinsicSize);

    if (style()->logicalWidth().isAuto()) {
        bool heightIsAuto = style()->logicalHeight().isAuto();
        bool hasIntrinsicWidth = !isPercentageIntrinsicSize && constrainedSize.width() > 0;

        // If 'height' and 'width' both have computed values of 'auto' and the element also has an intrinsic width, then that intrinsic width is the used value of 'width'.
        if (heightIsAuto && hasIntrinsicWidth)
            return computeReplacedLogicalWidthRespectingMinMaxWidth(constrainedSize.width(), shouldComputePreferred);

        bool hasIntrinsicHeight = !isPercentageIntrinsicSize && constrainedSize.height() > 0;
        if (intrinsicRatio || isPercentageIntrinsicSize) {
            // If 'height' and 'width' both have computed values of 'auto' and the element has no intrinsic width, but does have an intrinsic height and intrinsic ratio;
            // or if 'width' has a computed value of 'auto', 'height' has some other computed value, and the element does have an intrinsic ratio; then the used value
            // of 'width' is: (used height) * (intrinsic ratio)
            if (intrinsicRatio && ((heightIsAuto && !hasIntrinsicWidth && hasIntrinsicHeight) || !heightIsAuto)) {
                LayoutUnit logicalHeight = computeReplacedLogicalHeight();
                return computeReplacedLogicalWidthRespectingMinMaxWidth(roundToInt(round(logicalHeight * intrinsicRatio)), shouldComputePreferred);

            // If 'height' and 'width' both have computed values of 'auto' and the element has an intrinsic ratio but no intrinsic height or width, then the used value of
            // 'width' is undefined in CSS 2.1. However, it is suggested that, if the containing block's width does not itself depend on the replaced element's width, then
            // the used value of 'width' is calculated from the constraint equation used for block-level, non-replaced elements in normal flow.
            if (heightIsAuto && !hasIntrinsicWidth && !hasIntrinsicHeight) {
                // The aforementioned 'constraint equation' used for block-level, non-replaced elements in normal flow:
                // 'margin-left' + 'border-left-width' + 'padding-left' + 'width' + 'padding-right' + 'border-right-width' + 'margin-right' = width of containing block
                LayoutUnit logicalWidth;
                if (RenderBlock* blockWithWidth = firstContainingBlockWithLogicalWidth(this))
                    logicalWidth = blockWithWidth->computeReplacedLogicalWidthRespectingMinMaxWidth(blockWithWidth->computeReplacedLogicalWidthUsing(blockWithWidth->style()->logicalWidth()), shouldComputePreferred);
                    logicalWidth = containingBlock()->availableLogicalWidth();

                // This solves above equation for 'width' (== logicalWidth).
                LayoutUnit marginStart = minimumValueForLength(style()->marginStart(), logicalWidth);
                LayoutUnit marginEnd = minimumValueForLength(style()->marginEnd(), logicalWidth);
                logicalWidth = max<LayoutUnit>(0, logicalWidth - (marginStart + marginEnd + (width() - clientWidth())));
                if (isPercentageIntrinsicSize)
                    logicalWidth = logicalWidth * constrainedSize.width() / 100;
                return computeReplacedLogicalWidthRespectingMinMaxWidth(logicalWidth, shouldComputePreferred);

        // Otherwise, if 'width' has a computed value of 'auto', and the element has an intrinsic width, then that intrinsic width is the used value of 'width'.
        if (hasIntrinsicWidth)
            return computeReplacedLogicalWidthRespectingMinMaxWidth(constrainedSize.width(), shouldComputePreferred);

        // Otherwise, if 'width' has a computed value of 'auto', but none of the conditions above are met, then the used value of 'width' becomes 300px. If 300px is too
        // wide to fit the device, UAs should use the width of the largest rectangle that has a 2:1 ratio and fits the device instead.
        // Note: We fall through and instead return intrinsicLogicalWidth() here - to preserve existing WebKit behavior, which might or might not be correct, or desired.
        // Changing this to return cDefaultWidth, will affect lots of test results. Eg. some tests assume that a blank <img> tag (which implies width/height=auto)
        // has no intrinsic size, which is wrong per CSS 2.1, but matches our behavior since a long time.

    return computeReplacedLogicalWidthRespectingMinMaxWidth(intrinsicLogicalWidth(), shouldComputePreferred);

LayoutUnit RenderReplaced::computeReplacedLogicalHeight() const
    // 10.5 Content height: the 'height' property:
    if (hasReplacedLogicalHeight())
        return computeReplacedLogicalHeightRespectingMinMaxHeight(computeReplacedLogicalHeightUsing(style()->logicalHeight()));

    RenderBox* contentRenderer = embeddedContentBox();

    // 10.6.2 Inline, replaced elements:
    bool isPercentageIntrinsicSize = false;
    double intrinsicRatio = 0;
    FloatSize constrainedSize;
    computeAspectRatioInformationForRenderBox(contentRenderer, constrainedSize, intrinsicRatio, isPercentageIntrinsicSize);

    bool widthIsAuto = style()->logicalWidth().isAuto();
    bool hasIntrinsicHeight = !isPercentageIntrinsicSize && constrainedSize.height() > 0;

    // If 'height' and 'width' both have computed values of 'auto' and the element also has an intrinsic height, then that intrinsic height is the used value of 'height'.
    if (widthIsAuto && hasIntrinsicHeight)
        return computeReplacedLogicalHeightRespectingMinMaxHeight(constrainedSize.height());

    // Otherwise, if 'height' has a computed value of 'auto', and the element has an intrinsic ratio then the used value of 'height' is:
    // (used width) / (intrinsic ratio)
    if (intrinsicRatio)
        return computeReplacedLogicalHeightRespectingMinMaxHeight(roundToInt(round(availableLogicalWidth() / intrinsicRatio)));

    // Otherwise, if 'height' has a computed value of 'auto', and the element has an intrinsic height, then that intrinsic height is the used value of 'height'.
    if (hasIntrinsicHeight)
        return computeReplacedLogicalHeightRespectingMinMaxHeight(constrainedSize.height());

    // Otherwise, if 'height' has a computed value of 'auto', but none of the conditions above are met, then the used value of 'height' must be set to the height
    // of the largest rectangle that has a 2:1 ratio, has a height not greater than 150px, and has a width not greater than the device width.
    return computeReplacedLogicalHeightRespectingMinMaxHeight(intrinsicLogicalHeight());

void RenderReplaced::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const
    minLogicalWidth = maxLogicalWidth = intrinsicLogicalWidth();

void RenderReplaced::computePreferredLogicalWidths()

    // We cannot resolve any percent logical width here as the available logical
    // width may not be set on our containing block.
    if (style()->logicalWidth().isPercent())
        computeIntrinsicLogicalWidths(m_minPreferredLogicalWidth, m_maxPreferredLogicalWidth);
        m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = computeReplacedLogicalWidth(ComputePreferred);

    RenderStyle* styleToUse = style();
    if (styleToUse->logicalWidth().isPercent() || styleToUse->logicalMaxWidth().isPercent() || hasRelativeIntrinsicLogicalWidth())
        m_minPreferredLogicalWidth = 0;

    if (styleToUse->logicalMinWidth().isFixed() && styleToUse->logicalMinWidth().value() > 0) {
        m_maxPreferredLogicalWidth = max(m_maxPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse->logicalMinWidth().value()));
        m_minPreferredLogicalWidth = max(m_minPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse->logicalMinWidth().value()));
    if (styleToUse->logicalMaxWidth().isFixed()) {
        m_maxPreferredLogicalWidth = min(m_maxPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse->logicalMaxWidth().value()));
        m_minPreferredLogicalWidth = min(m_minPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse->logicalMaxWidth().value()));

    LayoutUnit borderAndPadding = borderAndPaddingLogicalWidth();
    m_minPreferredLogicalWidth += borderAndPadding;
    m_maxPreferredLogicalWidth += borderAndPadding;


VisiblePosition RenderReplaced::positionForPoint(const LayoutPoint& point)
    // FIXME: This code is buggy if the replaced element is relative positioned.
    InlineBox* box = inlineBoxWrapper();
    RootInlineBox* rootBox = box ? box->root() : 0;
    LayoutUnit top = rootBox ? rootBox->selectionTop() : logicalTop();
    LayoutUnit bottom = rootBox ? rootBox->selectionBottom() : logicalBottom();
    LayoutUnit blockDirectionPosition = isHorizontalWritingMode() ? point.y() + y() : point.x() + x();
    LayoutUnit lineDirectionPosition = isHorizontalWritingMode() ? point.x() + x() : point.y() + y();
    if (blockDirectionPosition < top)
        return createVisiblePosition(caretMinOffset(), DOWNSTREAM); // coordinates are above
    if (blockDirectionPosition >= bottom)
        return createVisiblePosition(caretMaxOffset(), DOWNSTREAM); // coordinates are below
    if (node()) {
        if (lineDirectionPosition <= logicalLeft() + (logicalWidth() / 2))
            return createVisiblePosition(0, DOWNSTREAM);
        return createVisiblePosition(1, DOWNSTREAM);

    return RenderBox::positionForPoint(point);

LayoutRect RenderReplaced::selectionRectForRepaint(const RenderLayerModelObject* repaintContainer, bool clipToVisibleContent)

    if (!isSelected())
        return LayoutRect();
    LayoutRect rect = localSelectionRect();
    if (clipToVisibleContent)
        computeRectForRepaint(repaintContainer, rect);
        rect = localToContainerQuad(FloatRect(rect), repaintContainer).enclosingBoundingBox();
    return rect;

LayoutRect RenderReplaced::localSelectionRect(bool checkWhetherSelected) const
    if (checkWhetherSelected && !isSelected())
        return LayoutRect();

    if (!m_inlineBoxWrapper)
        // We're a block-level replaced element.  Just return our own dimensions.
        return LayoutRect(LayoutPoint(), size());
    RootInlineBox* root = m_inlineBoxWrapper->root();
    LayoutUnit newLogicalTop = root->block()->style()->isFlippedBlocksWritingMode() ? m_inlineBoxWrapper->logicalBottom() - root->selectionBottom() : root->selectionTop() - m_inlineBoxWrapper->logicalTop();
    if (root->block()->style()->isHorizontalWritingMode())
        return LayoutRect(0, newLogicalTop, width(), root->selectionHeight());
    return LayoutRect(newLogicalTop, 0, root->selectionHeight(), height());

void RenderReplaced::setSelectionState(SelectionState state)
    // The selection state for our containing block hierarchy is updated by the base class call.

    if (m_inlineBoxWrapper && canUpdateSelectionOnRootLineBoxes())
        if (RootInlineBox* root = m_inlineBoxWrapper->root())

bool RenderReplaced::isSelected() const
    SelectionState s = selectionState();
    if (s == SelectionNone)
        return false;
    if (s == SelectionInside)
        return true;

    int selectionStart, selectionEnd;
    selectionStartEnd(selectionStart, selectionEnd);
    if (s == SelectionStart)
        return selectionStart == 0;
    int end = node()->hasChildNodes() ? node()->childNodeCount() : 1;
    if (s == SelectionEnd)
        return selectionEnd == end;
    if (s == SelectionBoth)
        return selectionStart == 0 && selectionEnd == end;
    return false;

LayoutRect RenderReplaced::clippedOverflowRectForRepaint(const RenderLayerModelObject* repaintContainer) const
    if (style()->visibility() != VISIBLE && !enclosingLayer()->hasVisibleContent())
        return LayoutRect();

    // The selectionRect can project outside of the overflowRect, so take their union
    // for repainting to avoid selection painting glitches.
    LayoutRect r = unionRect(localSelectionRect(false), visualOverflowRect());

    RenderView* v = view();
    if (v) {
        // FIXME: layoutDelta needs to be applied in parts before/after transforms and
        // repaint containers.

    if (style()) {
        if (v)
    computeRectForRepaint(repaintContainer, r);
    return r;