render_box.cpp

konqueror3 embedded版本, KDE环境下的当家浏览器的嵌入式版本源码包.

    return width;
}

void RenderBox::calcHorizontalMargins(const Length& ml, const Length& mr, int cw)
{
    if (isFloating() || isInline()) // Inline blocks/tables and floats don't have their margins increased.
    {
        m_marginLeft = ml.minWidth(cw);
        m_marginRight = mr.minWidth(cw);
    }
    else
    {
        if ( (ml.isVariable() && mr.isVariable()) ||
             (!ml.isVariable() && !mr.isVariable() &&
                containingBlock()->style()->textAlign() == KHTML_CENTER) )
        {
            m_marginLeft = (cw - m_width)/2;
            if (m_marginLeft<0) m_marginLeft=0;
            m_marginRight = cw - m_width - m_marginLeft;
        }
        else if (mr.isVariable() ||
                 (!ml.isVariable() && containingBlock()->style()->direction() == RTL &&
                  containingBlock()->style()->textAlign() == KHTML_LEFT))
        {
            m_marginLeft = ml.width(cw);
            m_marginRight = cw - m_width - m_marginLeft;
        }
        else if (ml.isVariable() ||
                 (!mr.isVariable() && containingBlock()->style()->direction() == LTR &&
                  containingBlock()->style()->textAlign() == KHTML_RIGHT))
        {
            m_marginRight = mr.width(cw);
            m_marginLeft = cw - m_width - m_marginRight;
        }
        else
        {
            m_marginLeft = ml.minWidth(cw);
            m_marginRight = mr.minWidth(cw);
        }
    }
}

void RenderBox::calcHeight()
{

#ifdef DEBUG_LAYOUT
    kdDebug( 6040 ) << "RenderBox::calcHeight()" << endl;
#endif

    //cell height is managed by table, inline elements do not have a height property.
    if ( isTableCell() || (isInline() && !isReplaced()) )
        return;

    if (isPositioned())
        calcAbsoluteVertical();
    else
    {
        calcVerticalMargins();

        // For tables, calculate margins only
        if (isTable())
            return;

        Length h;
        bool treatAsReplaced = isReplaced() && !isInlineBlockOrInlineTable();
        bool checkMinMaxHeight = false;

        if ( treatAsReplaced )
            h = Length( calcReplacedHeight(), Fixed );
        else {
            h = style()->height();
            checkMinMaxHeight = true;
        }

        int height;
        if (checkMinMaxHeight) {
            height = calcHeightUsing(style()->height());
            if (height == -1)
                height = m_height;
            int minH = calcHeightUsing(style()->minHeight()); // Leave as -1 if unset.
            int maxH = style()->maxHeight().value() == UNDEFINED ? height : calcHeightUsing(style()->maxHeight());
            if (maxH == -1)
                maxH = height;
            height = kMin(maxH, height);
            height = kMax(minH, height);
        }
        else {
            // The only times we don't check min/max height are when a fixed length has
            // been given as an override.  Just use that.
            height = calcBoxHeight(h.value());
        }

        if (height<m_height && !overhangingContents() && style()->overflow()==OVISIBLE)
            setOverhangingContents();

        m_height = height;
    }

    // Unfurling marquees override with the furled height.
    if (style()->overflow() == OMARQUEE && m_layer && m_layer->marquee() &&
        m_layer->marquee()->isUnfurlMarquee() && !m_layer->marquee()->isHorizontal()) {
        m_layer->marquee()->setEnd(m_height);
        m_height = kMin(m_height, m_layer->marquee()->unfurlPos());
    }

}

int RenderBox::calcHeightUsing(const Length& h)
{
    int height = -1;
    if (!h.isVariable()) {
        if (h.isFixed())
            height = h.value();
        else if (h.isPercent())
            height = calcPercentageHeight(h);
        if (height != -1) {
            height = calcBoxHeight(height);
            return height;
        }
    }
    return height;
}

int RenderBox::calcPercentageHeight(const Length& height, bool treatAsReplaced) const
{
    int result = -1;
    RenderBlock* cb = containingBlock();
    // In quirk mode, table cells violate what the CSS spec says to do with heights.
    if (cb->isTableCell() && style()->htmlHacks()) {
        result = static_cast<RenderTableCell*>(cb)->cellPercentageHeight();
    }
    // Otherwise we only use our percentage height if our containing block had a specified
    // height.
    else if (cb->style()->height().isFixed())
        result = cb->calcContentHeight(cb->style()->height().value());
    else if (cb->style()->height().isPercent()) {
        // We need to recur and compute the percentage height for our containing block.
        result = cb->calcPercentageHeight(cb->style()->height(), treatAsReplaced);
        if (result != -1)
            result = cb->calcContentHeight(result);
    }
    else if (cb->isCanvas()) {
        if (!canvas()->pagedMode())
            result = static_cast<RenderCanvas*>(cb)->viewportHeight();
        else
            result = static_cast<RenderCanvas*>(cb)->height();
        result -= cb->style()->borderTopWidth() - cb->style()->borderBottomWidth();
        result -= cb->paddingTop() + cb->paddingBottom();
    }
    else if (cb->isBody() && style()->htmlHacks() &&
                             cb->style()->height().isVariable() && !cb->isFloatingOrPositioned()) {
        int margins = cb->collapsedMarginTop() + cb->collapsedMarginBottom();
        int visHeight = canvas()->viewportHeight();
        RenderObject* p = cb->parent();
        result = visHeight - (margins + p->marginTop() + p->marginBottom() +
                              p->borderTop() + p->borderBottom() +
                              p->paddingTop() + p->paddingBottom());
    }
    else if (cb->isAnonymousBlock() || treatAsReplaced && style()->htmlHacks()) {
        // IE quirk.
        result = cb->calcPercentageHeight(cb->style()->height(), treatAsReplaced);
    }
    if (result != -1) {
        result = height.width(result);
        if (cb->isTableCell() && !isTable() && style()->boxSizing() != BORDER_BOX) {
            result -= (borderTop() + paddingTop() + borderBottom() + paddingBottom());
            result = kMax(0, result);
        }
    }
    return result;
}

short RenderBox::calcReplacedWidth() const
{
    int width = calcReplacedWidthUsing(Width);
    int minW = calcReplacedWidthUsing(MinWidth);
    int maxW = style()->maxWidth().value() == UNDEFINED ? width : calcReplacedWidthUsing(MaxWidth);

    if (width > maxW)
        width = maxW;

    if (width < minW)
        width = minW;

    return width;
}

int RenderBox::calcReplacedWidthUsing(WidthType widthType) const
{
    Length w;
    if (widthType == Width)
        w = style()->width();
    else if (widthType == MinWidth)
        w = style()->minWidth();
    else
        w = style()->maxWidth();

    switch (w.type()) {
    case Fixed:
        return w.value();
    case Percent:
    {
        const int cw = containingBlockWidth();
        if (cw > 0) {
            int result = w.minWidth(cw);
            return result;
        }
    }
    // fall through
    default:
        return intrinsicWidth();
    }
}

int RenderBox::calcReplacedHeight() const
{
    int height = calcReplacedHeightUsing(Height);
    int minH = calcReplacedHeightUsing(MinHeight);
    int maxH = style()->maxHeight().value() == UNDEFINED ? height : calcReplacedHeightUsing(MaxHeight);

    if (height > maxH)
        height = maxH;

    if (height < minH)
        height = minH;

    return height;
}

int RenderBox::calcReplacedHeightUsing(HeightType heightType) const
{
    Length h;
    if (heightType == Height)
        h = style()->height();
    else if (heightType == MinHeight)
        h = style()->minHeight();
    else
        h = style()->maxHeight();
    switch( h.type() ) {
    case Fixed:
        return h.value();
    case Percent:
      {
        int th = calcPercentageHeight(h, true);
        if (th != -1)
            return th;
        // fall through
      }
    default:
        return intrinsicHeight();
    };
}

int RenderBox::availableHeight() const
{
    return availableHeightUsing(style()->height());
}

int RenderBox::availableHeightUsing(const Length& h) const
{
    if (h.isFixed())
        return calcContentHeight(h.value());

    if (isCanvas())
        if (static_cast<const RenderCanvas*>(this)->pagedMode())
            return static_cast<const RenderCanvas*>(this)->pageHeight();
        else
            return static_cast<const RenderCanvas*>(this)->viewportHeight();

    // We need to stop here, since we don't want to increase the height of the table
    // artificially.  We're going to rely on this cell getting expanded to some new
    // height, and then when we lay out again we'll use the calculation below.
    if (isTableCell() && (h.isVariable() || h.isPercent())) {
        const RenderTableCell* tableCell = static_cast<const RenderTableCell*>(this);
        return tableCell->cellPercentageHeight() -
	    (borderTop()+borderBottom()+paddingTop()+paddingBottom());
    }

    if (h.isPercent())
       return calcContentHeight(h.width(containingBlock()->availableHeight()));

    return containingBlock()->availableHeight();
}

void RenderBox::calcVerticalMargins()
{
    if( isTableCell() ) {
	// table margins are basically infinite
	m_marginTop = TABLECELLMARGIN;
	m_marginBottom = TABLECELLMARGIN;
	return;
    }

    Length tm = style()->marginTop();
    Length bm = style()->marginBottom();

    // margins are calculated with respect to the _width_ of
    // the containing block (8.3)
    int cw = containingBlock()->contentWidth();

    m_marginTop = tm.minWidth(cw);
    m_marginBottom = bm.minWidth(cw);
}

void RenderBox::setStaticX(short staticX)
{
    m_staticX = staticX;
}

void RenderBox::setStaticY(int staticY)
{
    m_staticY = staticY;
}

void RenderBox::calcAbsoluteHorizontal()
{
    const int AUTO = -666666;
    int l, r, cw;

    RenderObject* cb = container();
    int pab = (style()->boxSizing() == BORDER_BOX) ? 0 :
        borderLeft()+ borderRight()+ paddingLeft()+ paddingRight();

    l = r = AUTO;
    cw = containingBlockWidth() + cb->paddingLeft() + cb->paddingRight();

    if (!style()->left().isVariable())
        l = style()->left().width(cw);
    if (!style()->right().isVariable())
        r = style()->right().width(cw);

    int static_distance=0;
    if ((parent()->style()->direction()==LTR && (l==AUTO && r==AUTO ))
            || style()->left().isStatic())
    {
        // calc hypothetical location in the normal flow
        // used for 1) left=static-position
        //          2) left, right, width are all auto -> calc top -> 3.
        //          3) precalc for case 2 below

        // all positioned elements are blocks, so that
        // would be at the left edge

        static_distance = m_staticX - cb->borderLeft(); // Should already have been set through layout of the parent().
        for (RenderObject* po = parent(); po && po != cb; po = po->parent())
            static_distance += po->xPos();

        if (l==AUTO || style()->left().isStatic())
            l = static_distance;
    }

    else if ((parent()->style()->direction()==RTL && (l==AUTO && r==AUTO ))
            || style()->right().isStatic())
    {
        static_distance = m_staticX - cb->borderLeft(); // Should already have been set through layout of the parent().
        for (RenderObject* po = parent(); po && po != cb; po = po->parent())
            static_distance += po->xPos();

        if (r==AUTO || style()->right().isStatic())
            r = static_distance;
    }

    int w = m_width, ml, mr, x;
    calcAbsoluteHorizontalValues(Width, cb, cw, pab, static_distance, l, r, w, ml, mr, x);

    m_width = w;
    m_marginLeft = ml;
    m_marginRight = mr;
    m_x = x;

    // Avoid doing any work in the common case (where the values of min-width and max-width are their defaults).
    int minW = m_width, minML, minMR, minX;
    calcAbsoluteHorizontalValues(MinWidth, cb, cw, pab, static_distance, l, r, minW, minML, minMR, minX);

    int maxW = m_width, maxML, maxMR, maxX;
    if (style()->maxWidth().value() != UNDEFINED)
        calcAbsoluteHorizontalValues(MaxWidth, cb, cw, static_distance, pab, l, r, maxW, maxML, maxMR, maxX);

    if (m_width > maxW) {
        m_width = maxW;
        m_marginLeft = maxML;
        m_marginRight = maxMR;
        m_x = maxX;
    }

    if (m_width < minW) {
        m_width = minW;
        m_marginLeft = minML;
        m_marginRight = minMR;
        m_x = minX;
    }
}

void RenderBox::calcAbsoluteHorizontalValues(WidthType widthType, RenderObject* cb, int cw, int pab, int static_distance,
                                             int l, int r, int& w, int& ml, int& mr, int& x)
{
    const int AUTO = -666666;

    w = ml = mr = AUTO;

    if (!style()->marginLeft().isVariable())
        ml = style()->marginLeft().width(cw);
    if (!style()->marginRight().isVariable())
        mr = style()->marginRight().width(cw);

    Length width;
    if (widthType == Width)
        width = style()->width();
    else if (widthType == MinWidth)
        width = style()->minWidth();
    else
        width = style()->maxWidth();

    if (!width.isVariable())
        w = width.width(cw);
    else if (isReplaced())
        w = intrinsicWidth();

    if (l != AUTO && w != AUTO && r != AUTO) {
        // left, width, right all given, play with margins
        int ot = l + w + r + pab;

        if (ml==AUTO && mr==AUTO)
        {
            // both margins auto, solve for equality
            ml = (cw - ot)/2;
            mr = cw - ot - ml;
        }
        else if (ml==AUTO)
            // solve for left margin
            ml = cw - ot - mr;