C++ RenderTableCol类代码示例

RenderTableCol* RenderTableCol::enclosingColumnGroup() const
{
    if (!parent()->isRenderTableCol())
        return 0;

    RenderTableCol* parentColumnGroup = toRenderTableCol(parent());
    ASSERT(parentColumnGroup->isTableColumnGroup());
    ASSERT(isTableColumn());
    return parentColumnGroup;
}

Length RenderTableCell::styleOrColWidth() const
{
    Length w = style()->width();
    if (colSpan() > 1 || !w.isAuto())
        return w;
    RenderTableCol* tableCol = table()->colElement(col());
    if (tableCol) {
        w = tableCol->style()->width();
        
        // Column widths specified on <col> apply to the border box of the cell.
        // Percentages don't need to be handled since they're always treated this way (even when specified on the cells).
        // See Bugzilla bug 8126 for details.
        if (w.isFixed() && w.value() > 0)
            w = Length(max(0, w.value() - borderLeft() - borderRight() - paddingLeft() - paddingRight()), Fixed);
    }
    return w;
}

void HTMLTableColElement::parseAttribute(const Attribute& attribute)
{
    if (attribute.name() == spanAttr) {
        m_span = !attribute.isNull() ? attribute.value().toInt() : 1;
        if (renderer() && renderer()->isTableCol())
            renderer()->updateFromElement();
    } else if (attribute.name() == widthAttr) {
        if (!attribute.isEmpty()) {
            if (renderer() && renderer()->isTableCol()) {
                RenderTableCol* col = toRenderTableCol(renderer());
                int newWidth = width().toInt();
                if (newWidth != col->width())
                    col->setNeedsLayoutAndPrefWidthsRecalc();
            }
        }
    } else
        HTMLTablePartElement::parseAttribute(attribute);
}

void HTMLTableColElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
{
    if (name == spanAttr) {
        m_span = !value.isNull() ? value.toInt() : 1;
        if (renderer() && renderer()->isRenderTableCol())
            renderer()->updateFromElement();
    } else if (name == widthAttr) {
        if (!value.isEmpty()) {
            if (renderer() && renderer()->isRenderTableCol()) {
                RenderTableCol* col = toRenderTableCol(renderer());
                int newWidth = width().toInt();
                if (newWidth != col->width())
                    col->setNeedsLayoutAndPrefWidthsRecalc();
            }
        }
    } else
        HTMLTablePartElement::parseAttribute(name, value);
}

void TableSectionPainter::paintCell(RenderTableCell* cell, const PaintInfo& paintInfo, const LayoutPoint& paintOffset)
{
    LayoutPoint cellPoint = m_renderTableSection.flipForWritingModeForChild(cell, paintOffset);
    PaintPhase paintPhase = paintInfo.phase;
    RenderTableRow* row = toRenderTableRow(cell->parent());

    if (paintPhase == PaintPhaseBlockBackground || paintPhase == PaintPhaseChildBlockBackground) {
        // We need to handle painting a stack of backgrounds. This stack (from bottom to top) consists of
        // the column group, column, row group, row, and then the cell.
        RenderTableCol* column = m_renderTableSection.table()->colElement(cell->col());
        RenderTableCol* columnGroup = column ? column->enclosingColumnGroup() : 0;

        TableCellPainter tableCellPainter(*cell);

        RenderDrawingRecorder recorder(paintInfo.context, m_renderTableSection, paintPhase, tableCellPainter.paintBounds(paintOffset, TableCellPainter::AddOffsetFromParent));
        if (!recorder.canUseCachedDrawing()) {
            // Column groups and columns first.
            // FIXME: Columns and column groups do not currently support opacity, and they are being painted "too late" in
            // the stack, since we have already opened a transparency layer (potentially) for the table row group.
            // Note that we deliberately ignore whether or not the cell has a layer, since these backgrounds paint "behind" the
            // cell.
            tableCellPainter.paintBackgroundsBehindCell(paintInfo, cellPoint, columnGroup);
            tableCellPainter.paintBackgroundsBehindCell(paintInfo, cellPoint, column);

            // Paint the row group next.
            tableCellPainter.paintBackgroundsBehindCell(paintInfo, cellPoint, &m_renderTableSection);

            // Paint the row next, but only if it doesn't have a layer. If a row has a layer, it will be responsible for
            // painting the row background for the cell.
            if (!row->hasSelfPaintingLayer())
                tableCellPainter.paintBackgroundsBehindCell(paintInfo, cellPoint, row);
        }
    }
    if ((!cell->hasSelfPaintingLayer() && !row->hasSelfPaintingLayer()))
        cell->paint(paintInfo, cellPoint);
}

CollapsedBorderValue RenderTableCell::collapsedStartBorder() const
{
    RenderTable* table = this->table();
    bool isStartColumn = col() == 0;

    // For the start border, we need to check, in order of precedence:
    // (1) Our start border.
    int start = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderStartColor, table->style()->direction(), table->style()->writingMode());
    int end = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderEndColor, table->style()->direction(), table->style()->writingMode());
    CollapsedBorderValue result(&style()->borderStart(), style()->visitedDependentColor(start), BCELL);

    // (2) The end border of the preceding cell.
    if (RenderTableCell* prevCell = table->cellBefore(this)) {
        CollapsedBorderValue prevCellBorder = CollapsedBorderValue(&prevCell->style()->borderEnd(), prevCell->style()->visitedDependentColor(end), BCELL);
        result = chooseBorder(prevCellBorder, result);
        if (!result.exists())
            return result;
    } else if (isStartColumn) {
        // (3) Our row's start border.
        result = chooseBorder(result, CollapsedBorderValue(&parent()->style()->borderStart(), parent()->style()->visitedDependentColor(start), BROW));
        if (!result.exists())
            return result;
        
        // (4) Our row group's start border.
        result = chooseBorder(result, CollapsedBorderValue(&section()->style()->borderStart(), section()->style()->visitedDependentColor(start), BROWGROUP));
        if (!result.exists())
            return result;
    }
    
    // (5) Our column and column group's start borders.
    bool startColEdge;
    bool endColEdge;
    RenderTableCol* colElt = table->colElement(col(), &startColEdge, &endColEdge);
    if (colElt && startColEdge) {
        result = chooseBorder(result, CollapsedBorderValue(&colElt->style()->borderStart(), colElt->style()->visitedDependentColor(start), BCOL));
        if (!result.exists())
            return result;
        if (colElt->parent()->isTableCol() && !colElt->previousSibling()) {
            result = chooseBorder(result, CollapsedBorderValue(&colElt->parent()->style()->borderStart(), colElt->parent()->style()->visitedDependentColor(start), BCOLGROUP));
            if (!result.exists())
                return result;
        }
    }
    
    // (6) The end border of the preceding column.
    if (!isStartColumn) {
        colElt = table->colElement(col() -1, &startColEdge, &endColEdge);
        if (colElt && endColEdge) {
            CollapsedBorderValue endBorder = CollapsedBorderValue(&colElt->style()->borderEnd(), colElt->style()->visitedDependentColor(end), BCOL);
            result = chooseBorder(endBorder, result);
            if (!result.exists())
                return result;
        }
    } else {
        // (7) The table's start border.
        result = chooseBorder(result, CollapsedBorderValue(&table->style()->borderStart(), table->style()->visitedDependentColor(start), BTABLE));
        if (!result.exists())
            return result;
    }
    
    return result;
}

int FixedTableLayout::calcWidthArray(int)
{
    int usedWidth = 0;

    // iterate over all <col> elements
    unsigned nEffCols = m_table->numEffCols();
    m_width.resize(nEffCols);
    m_width.fill(Length(Auto));

    unsigned currentEffectiveColumn = 0;
    for (RenderTableCol* col = m_table->firstColumn(); col; col = col->nextColumn()) {
        col->computePreferredLogicalWidths();

        // Width specified by column-groups that have column child does not affect column width in fixed layout tables
        if (col->isTableColumnGroupWithColumnChildren())
            continue;

        Length colStyleLogicalWidth = col->style()->logicalWidth();
        int effectiveColWidth = 0;
        if (colStyleLogicalWidth.isFixed() && colStyleLogicalWidth.value() > 0)
            effectiveColWidth = colStyleLogicalWidth.value();

        unsigned span = col->span();
        while (span) {
            unsigned spanInCurrentEffectiveColumn;
            if (currentEffectiveColumn >= nEffCols) {
                m_table->appendColumn(span);
                nEffCols++;
                m_width.append(Length());
                spanInCurrentEffectiveColumn = span;
            } else {
                if (span < m_table->spanOfEffCol(currentEffectiveColumn)) {
                    m_table->splitColumn(currentEffectiveColumn, span);
                    nEffCols++;
                    m_width.append(Length());
                }
                spanInCurrentEffectiveColumn = m_table->spanOfEffCol(currentEffectiveColumn);
            }
            if ((colStyleLogicalWidth.isFixed() || colStyleLogicalWidth.isPercent()) && colStyleLogicalWidth.isPositive()) {
                m_width[currentEffectiveColumn] = colStyleLogicalWidth;
                m_width[currentEffectiveColumn] *= spanInCurrentEffectiveColumn;
                usedWidth += effectiveColWidth * spanInCurrentEffectiveColumn;
            }
            span -= spanInCurrentEffectiveColumn;
            currentEffectiveColumn++;
        }
    }

    // Iterate over the first row in case some are unspecified.
    RenderTableSection* section = m_table->topNonEmptySection();
    if (!section)
        return usedWidth;

    unsigned currentColumn = 0;

    RenderObject* firstRow = section->firstChild();
    for (RenderObject* child = firstRow->firstChild(); child; child = child->nextSibling()) {
        if (!child->isTableCell())
            continue;

        RenderTableCell* cell = toRenderTableCell(child);
        if (cell->preferredLogicalWidthsDirty())
            cell->computePreferredLogicalWidths();

        Length logicalWidth = cell->styleOrColLogicalWidth();
        unsigned span = cell->colSpan();
        int fixedBorderBoxLogicalWidth = 0;
        if (logicalWidth.isFixed() && logicalWidth.isPositive()) {
            fixedBorderBoxLogicalWidth = cell->adjustBorderBoxLogicalWidthForBoxSizing(logicalWidth.value());
            logicalWidth.setValue(fixedBorderBoxLogicalWidth);
        }

        unsigned usedSpan = 0;
        while (usedSpan < span && currentColumn < nEffCols) {
            float eSpan = m_table->spanOfEffCol(currentColumn);
            // Only set if no col element has already set it.
            if (m_width[currentColumn].isAuto() && logicalWidth.type() != Auto) {
                m_width[currentColumn] = logicalWidth;
                m_width[currentColumn] *= eSpan / span;
                usedWidth += fixedBorderBoxLogicalWidth * eSpan / span;
            }
            usedSpan += eSpan;
            ++currentColumn;
        }
    }

    return usedWidth;
}

CollapsedBorderValue RenderTableCell::collapsedBottomBorder() const
{
    // For border top, we need to check, in order of precedence:
    // (1) Our bottom border.
    CollapsedBorderValue result = CollapsedBorderValue(&style()->borderBottom(), BCELL);
    
    RenderTableCell* nextCell = table()->cellBelow(this);
    if (nextCell) {
        // (2) A following cell's top border.
        result = compareBorders(result, CollapsedBorderValue(&nextCell->style()->borderTop(), BCELL));
        if (!result.exists())
            return result;
    }
    
    // (3) Our row's bottom border. (FIXME: Deal with rowspan!)
    result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderBottom(), BROW));
    if (!result.exists())
        return result;
    
    // (4) The next row's top border.
    if (nextCell) {
        result = compareBorders(result, CollapsedBorderValue(&nextCell->parent()->style()->borderTop(), BROW));
        if (!result.exists())
            return result;
    }
    
    // Now check row groups.
    RenderTableSection* currSection = section();
    if (row() + rowSpan() >= currSection->numRows()) {
        // (5) Our row group's bottom border.
        result = compareBorders(result, CollapsedBorderValue(&currSection->style()->borderBottom(), BROWGROUP));
        if (!result.exists())
            return result;
        
        // (6) Following row group's top border.
        currSection = table()->sectionBelow(currSection);
        if (currSection) {
            result = compareBorders(result, CollapsedBorderValue(&currSection->style()->borderTop(), BROWGROUP));
            if (!result.exists())
                return result;
        }
    }
    
    if (!currSection) {
        // (8) Our column and column group's bottom borders.
        RenderTableCol* colElt = table()->colElement(col());
        if (colElt) {
            result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderBottom(), BCOL));
            if (!result.exists()) return result;
            if (colElt->parent()->isTableCol()) {
                result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderBottom(), BCOLGROUP));
                if (!result.exists())
                    return result;
            }
        }
        
        // (9) The table's bottom border.
        result = compareBorders(result, CollapsedBorderValue(&table()->style()->borderBottom(), BTABLE));
        if (!result.exists())
            return result;
    }
    
    return result;    
}

int FixedTableLayout::calcWidthArray(int tableWidth)
{
    int usedWidth = 0;

    // iterate over all <col> elements
    RenderObject* child = m_table->firstChild();
    int cCol = 0;
    int nEffCols = m_table->numEffCols();
    m_width.resize(nEffCols);
    m_width.fill(Length(Auto));

    Length grpWidth;
    while (child) {
        if (child->isTableCol()) {
            RenderTableCol *col = static_cast<RenderTableCol *>(child);
            int span = col->span();
            if (col->firstChild())
                grpWidth = col->style()->width();
            else {
                Length w = col->style()->width();
                if (w.isAuto())
                    w = grpWidth;
                int effWidth = 0;
                if (w.isFixed() && w.value() > 0)
                    effWidth = w.value();
                
                int usedSpan = 0;
                int i = 0;
                while (usedSpan < span) {
                    if(cCol + i >= nEffCols) {
                        m_table->appendColumn(span - usedSpan);
                        nEffCols++;
                        m_width.resize(nEffCols);
                        m_width[nEffCols-1] = Length();
                    }
                    int eSpan = m_table->spanOfEffCol(cCol+i);
                    if ((w.isFixed() || w.isPercent()) && w.isPositive()) {
                        m_width[cCol + i].setRawValue(w.type(), w.rawValue() * eSpan);
                        usedWidth += effWidth * eSpan;
                    }
                    usedSpan += eSpan;
                    i++;
                }
                cCol += i;
            }
        } else
            break;

        RenderObject *next = child->firstChild();
        if (!next)
            next = child->nextSibling();
        if (!next && child->parent()->isTableCol()) {
            next = child->parent()->nextSibling();
            grpWidth = Length();
        }
        child = next;
    }

    // Iterate over the first row in case some are unspecified.
    RenderTableSection* section = m_table->header();
    if (!section)
        section = m_table->firstBody();
    if (!section)
        section = m_table->footer();
    if (section && !section->numRows())
        section = m_table->sectionBelow(section, true);
    if (section) {
        cCol = 0;
        RenderObject* firstRow = section->firstChild();
        child = firstRow->firstChild();
        while (child) {
            if (child->isTableCell()) {
                RenderTableCell* cell = static_cast<RenderTableCell*>(child);
                if (cell->prefWidthsDirty())
                    cell->calcPrefWidths();

                Length w = cell->styleOrColWidth();
                int span = cell->colSpan();
                int effWidth = 0;
                if (w.isFixed() && w.isPositive())
                    effWidth = w.value();
                
                int usedSpan = 0;
                int i = 0;
                while (usedSpan < span) {
                    ASSERT(cCol + i < nEffCols);
                    int eSpan = m_table->spanOfEffCol(cCol + i);
                    // Only set if no col element has already set it.
                    if (m_width[cCol + i].isAuto() && w.type() != Auto) {
                        m_width[cCol + i].setRawValue(w.type(), w.rawValue() * eSpan / span);
                        usedWidth += effWidth * eSpan / span;
                    }
                    usedSpan += eSpan;
                    i++;
                }
                cCol += i;
            }
            child = child->nextSibling();
        }
    }
//.........这里部分代码省略.........

CollapsedBorderValue RenderTableCell::collapsedAfterBorder() const
{
    RenderTable* table = this->table();

    // For after border, we need to check, in order of precedence:
    // (1) Our after border.
    int before = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderBeforeColor, table->style()->direction(), table->style()->writingMode());
    int after = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderAfterColor, table->style()->direction(), table->style()->writingMode());
    CollapsedBorderValue result = CollapsedBorderValue(&style()->borderAfter(), style()->visitedDependentColor(after), BCELL);
    
    RenderTableCell* nextCell = table->cellBelow(this);
    if (nextCell) {
        // (2) An after cell's before border.
        result = chooseBorder(result, CollapsedBorderValue(&nextCell->style()->borderBefore(), nextCell->style()->visitedDependentColor(before), BCELL));
        if (!result.exists())
            return result;
    }
    
    // (3) Our row's after border. (FIXME: Deal with rowspan!)
    result = chooseBorder(result, CollapsedBorderValue(&parent()->style()->borderAfter(), parent()->style()->visitedDependentColor(after), BROW));
    if (!result.exists())
        return result;
    
    // (4) The next row's before border.
    if (nextCell) {
        result = chooseBorder(result, CollapsedBorderValue(&nextCell->parent()->style()->borderBefore(), nextCell->parent()->style()->visitedDependentColor(before), BROW));
        if (!result.exists())
            return result;
    }
    
    // Now check row groups.
    RenderTableSection* currSection = section();
    if (row() + rowSpan() >= currSection->numRows()) {
        // (5) Our row group's after border.
        result = chooseBorder(result, CollapsedBorderValue(&currSection->style()->borderAfter(), currSection->style()->visitedDependentColor(after), BROWGROUP));
        if (!result.exists())
            return result;
        
        // (6) Following row group's before border.
        currSection = table->sectionBelow(currSection);
        if (currSection) {
            result = chooseBorder(result, CollapsedBorderValue(&currSection->style()->borderBefore(), currSection->style()->visitedDependentColor(before), BROWGROUP));
            if (!result.exists())
                return result;
        }
    }
    
    if (!currSection) {
        // (8) Our column and column group's after borders.
        RenderTableCol* colElt = table->colElement(col());
        if (colElt) {
            result = chooseBorder(result, CollapsedBorderValue(&colElt->style()->borderAfter(), colElt->style()->visitedDependentColor(after), BCOL));
            if (!result.exists()) return result;
            if (colElt->parent()->isTableCol()) {
                result = chooseBorder(result, CollapsedBorderValue(&colElt->parent()->style()->borderAfter(), colElt->parent()->style()->visitedDependentColor(after), BCOLGROUP));
                if (!result.exists())
                    return result;
            }
        }
        
        // (9) The table's after border.
        result = chooseBorder(result, CollapsedBorderValue(&table->style()->borderAfter(), table->style()->visitedDependentColor(after), BTABLE));
        if (!result.exists())
            return result;
    }
    
    return result;    
}

int FixedTableLayout::calcWidthArray()
{
    // FIXME: We might want to wait until we have all of the first row before computing for the first time.
    int usedWidth = 0;

    // iterate over all <col> elements
    unsigned nEffCols = m_table->numEffCols();
    m_width.resize(nEffCols);
    m_width.fill(Length(Auto));

    unsigned currentEffectiveColumn = 0;
    for (RenderTableCol* col = m_table->firstColumn(); col; col = col->nextColumn()) {
        // RenderTableCols don't have the concept of preferred logical width, but we need to clear their dirty bits
        // so that if we call setPreferredWidthsDirty(true) on a col or one of its descendants, we'll mark it's
        // ancestors as dirty.
        col->clearPreferredLogicalWidthsDirtyBits();

        // Width specified by column-groups that have column child does not affect column width in fixed layout tables
        if (col->isTableColumnGroupWithColumnChildren())
            continue;

        Length colStyleLogicalWidth = col->style().logicalWidth();
        int effectiveColWidth = 0;
        if (colStyleLogicalWidth.isFixed() && colStyleLogicalWidth.value() > 0)
            effectiveColWidth = colStyleLogicalWidth.value();

        unsigned span = col->span();
        while (span) {
            unsigned spanInCurrentEffectiveColumn;
            if (currentEffectiveColumn >= nEffCols) {
                m_table->appendColumn(span);
                nEffCols++;
                m_width.append(Length());
                spanInCurrentEffectiveColumn = span;
            } else {
                if (span < m_table->spanOfEffCol(currentEffectiveColumn)) {
                    m_table->splitColumn(currentEffectiveColumn, span);
                    nEffCols++;
                    m_width.append(Length());
                }
                spanInCurrentEffectiveColumn = m_table->spanOfEffCol(currentEffectiveColumn);
            }
            if ((colStyleLogicalWidth.isFixed() || colStyleLogicalWidth.isPercent()) && colStyleLogicalWidth.isPositive()) {
                m_width[currentEffectiveColumn] = colStyleLogicalWidth;
                m_width[currentEffectiveColumn] *= spanInCurrentEffectiveColumn;
                usedWidth += effectiveColWidth * spanInCurrentEffectiveColumn;
            }
            span -= spanInCurrentEffectiveColumn;
            currentEffectiveColumn++;
        }
    }

    // Iterate over the first row in case some are unspecified.
    RenderTableSection* section = m_table->topNonEmptySection();
    if (!section)
        return usedWidth;

    unsigned currentColumn = 0;

    RenderTableRow* firstRow = section->firstRow();
    for (RenderTableCell* cell = firstRow->firstCell(); cell; cell = cell->nextCell()) {
        Length logicalWidth = cell->styleOrColLogicalWidth();
        unsigned span = cell->colSpan();
        int fixedBorderBoxLogicalWidth = 0;
        // FIXME: Support other length types. If the width is non-auto, it should probably just use
        // RenderBox::computeLogicalWidthInRegionUsing to compute the width.
        if (logicalWidth.isFixed() && logicalWidth.isPositive()) {
            fixedBorderBoxLogicalWidth = cell->adjustBorderBoxLogicalWidthForBoxSizing(logicalWidth.value());
            logicalWidth.setValue(Fixed, fixedBorderBoxLogicalWidth);
        }

        unsigned usedSpan = 0;
        while (usedSpan < span && currentColumn < nEffCols) {
            float eSpan = m_table->spanOfEffCol(currentColumn);
            // Only set if no col element has already set it.
            if (m_width[currentColumn].isAuto() && logicalWidth.type() != Auto) {
                m_width[currentColumn] = logicalWidth;
                m_width[currentColumn] *= eSpan / span;
                usedWidth += fixedBorderBoxLogicalWidth * eSpan / span;
            }
            usedSpan += eSpan;
            ++currentColumn;
        }

        // FixedTableLayout doesn't use min/maxPreferredLogicalWidths, but we need to clear the
        // dirty bit on the cell so that we'll correctly mark its ancestors dirty
        // in case we later call setPreferredLogicalWidthsDirty(true) on it later.
        if (cell->preferredLogicalWidthsDirty())
            cell->setPreferredLogicalWidthsDirty(false);
    }

    return usedWidth;
}

int FixedTableLayout::calcWidthArray(int)
{
    int usedWidth = 0;

    // iterate over all <col> elements
    RenderObject* child = m_table->firstChild();
    int nEffCols = m_table->numEffCols();
    m_width.resize(nEffCols);
    m_width.fill(Length(Auto));

    int currentEffectiveColumn = 0;
    Length grpWidth;
    while (child && child->isTableCol()) {
        RenderTableCol* col = toRenderTableCol(child);
        if (col->firstChild())
            grpWidth = col->style()->logicalWidth();
        else {
            Length w = col->style()->logicalWidth();
            if (w.isAuto())
                w = grpWidth;
            int effWidth = 0;
            if (w.isFixed() && w.value() > 0)
                effWidth = w.value();

            int span = col->span();
            while (span) {
                int spanInCurrentEffectiveColumn;
                if (currentEffectiveColumn >= nEffCols) {
                    m_table->appendColumn(span);
                    nEffCols++;
                    m_width.append(Length());
                    spanInCurrentEffectiveColumn = span;
                } else {
                    if (span < m_table->spanOfEffCol(currentEffectiveColumn)) {
                        m_table->splitColumn(currentEffectiveColumn, span);
                        nEffCols++;
                        m_width.append(Length());
                    }
                    spanInCurrentEffectiveColumn = m_table->spanOfEffCol(currentEffectiveColumn);
                }
                if ((w.isFixed() || w.isPercent()) && w.isPositive()) {
                    m_width[currentEffectiveColumn] = w;
                    m_width[currentEffectiveColumn] *= spanInCurrentEffectiveColumn;
                    usedWidth += effWidth * spanInCurrentEffectiveColumn;
                }
                span -= spanInCurrentEffectiveColumn;
                currentEffectiveColumn++;
            }
        }
        col->computePreferredLogicalWidths();

        RenderObject* next = child->firstChild();
        if (!next)
            next = child->nextSibling();
        if (!next && child->parent()->isTableCol()) {
            next = child->parent()->nextSibling();
            grpWidth = Length();
        }
        child = next;
    }

    // Iterate over the first row in case some are unspecified.
    RenderTableSection* section = m_table->topNonEmptySection();
    if (section) {
        int cCol = 0;
        RenderObject* firstRow = section->firstChild();
        child = firstRow->firstChild();
        while (child) {
            if (child->isTableCell()) {
                RenderTableCell* cell = toRenderTableCell(child);
                if (cell->preferredLogicalWidthsDirty())
                    cell->computePreferredLogicalWidths();

                Length w = cell->styleOrColLogicalWidth();
                int span = cell->colSpan();
                int effWidth = 0;
                if (w.isFixed() && w.isPositive())
                    effWidth = w.value();

                int usedSpan = 0;
                int i = 0;
                while (usedSpan < span && cCol + i < nEffCols) {
                    float eSpan = m_table->spanOfEffCol(cCol + i);
                    // Only set if no col element has already set it.
                    if (m_width[cCol + i].isAuto() && w.type() != Auto) {
                        m_width[cCol + i] = w;
                        m_width[cCol + i] *= eSpan / span;
                        usedWidth += effWidth * eSpan / span;
                    }
                    usedSpan += eSpan;
                    i++;
                }
                cCol += i;
            }
            child = child->nextSibling();
        }
    }

    return usedWidth;
}

CollapsedBorderValue RenderTableCell::collapsedEndBorder() const
{
    RenderTable* table = this->table();
    bool isEndColumn = table->colToEffCol(col() + colSpan() - 1) == table->numEffCols() - 1;

    // For end border, we need to check, in order of precedence:
    // (1) Our end border.
    int start = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderStartColor, table->style()->direction(), table->style()->writingMode());
    int end = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderEndColor, table->style()->direction(), table->style()->writingMode());
    CollapsedBorderValue result = CollapsedBorderValue(&style()->borderEnd(), style()->visitedDependentColor(end), BCELL);
    
    // (2) The start border of the following cell.
    if (!isEndColumn) {
        RenderTableCell* nextCell = table->cellAfter(this);
        if (nextCell && nextCell->style()) {
            CollapsedBorderValue startBorder = CollapsedBorderValue(&nextCell->style()->borderStart(), nextCell->style()->visitedDependentColor(start), BCELL);
            result = chooseBorder(result, startBorder);
            if (!result.exists())
                return result;
        }
    } else {
        // (3) Our row's end border.
        result = chooseBorder(result, CollapsedBorderValue(&parent()->style()->borderEnd(), parent()->style()->visitedDependentColor(end), BROW));
        if (!result.exists())
            return result;
        
        // (4) Our row group's end border.
        result = chooseBorder(result, CollapsedBorderValue(&section()->style()->borderEnd(), section()->style()->visitedDependentColor(end), BROWGROUP));
        if (!result.exists())
            return result;
    }
    
    // (5) Our column and column group's end borders.
    bool startColEdge;
    bool endColEdge;
    RenderTableCol* colElt = table->colElement(col() + colSpan() - 1, &startColEdge, &endColEdge);
    if (colElt && endColEdge) {
        result = chooseBorder(result, CollapsedBorderValue(&colElt->style()->borderEnd(), colElt->style()->visitedDependentColor(end), BCOL));
        if (!result.exists())
            return result;
        if (colElt->parent()->isTableCol() && !colElt->nextSibling()) {
            result = chooseBorder(result, CollapsedBorderValue(&colElt->parent()->style()->borderEnd(), colElt->parent()->style()->visitedDependentColor(end), BCOLGROUP));
            if (!result.exists())
                return result;
        }
    }
    
    // (6) The start border of the next column.
    if (!isEndColumn) {
        colElt = table->colElement(col() + colSpan(), &startColEdge, &endColEdge);
        if (colElt && startColEdge) {
            CollapsedBorderValue startBorder = CollapsedBorderValue(&colElt->style()->borderStart(), colElt->style()->visitedDependentColor(start), BCOL);
            result = chooseBorder(result, startBorder);
            if (!result.exists())
                return result;
        }
    } else {
        // (7) The table's end border.
        result = chooseBorder(result, CollapsedBorderValue(&table->style()->borderEnd(), table->style()->visitedDependentColor(end), BTABLE));
        if (!result.exists())
            return result;
    }
    
    return result;
}

CollapsedBorderValue RenderTableCell::collapsedRightBorder(bool rtl) const
{
    RenderTable* tableElt = table();
    bool rightmostColumn;
    if (rtl)
        rightmostColumn = col() == 0;
    else {
        int effCol = tableElt->colToEffCol(col() + colSpan() - 1);
        rightmostColumn = effCol == tableElt->numEffCols() - 1;
    }
    
    // For border right, we need to check, in order of precedence:
    // (1) Our right border.
    CollapsedBorderValue result = CollapsedBorderValue(&style()->borderRight(), BCELL);
    
    // (2) The left border of the cell to the right.
    if (!rightmostColumn) {
        RenderTableCell* nextCell = rtl ? tableElt->cellBefore(this) : tableElt->cellAfter(this);
        if (nextCell && nextCell->style()) {
            result = rtl ? compareBorders(CollapsedBorderValue(&nextCell->style()->borderLeft(), BCELL), result) : compareBorders(result, CollapsedBorderValue(&nextCell->style()->borderLeft(), BCELL));
            if (!result.exists())
                return result;
        }
    } else {
        // (3) Our row's right border.
        result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderRight(), BROW));
        if (!result.exists())
            return result;
        
        // (4) Our row group's right border.
        result = compareBorders(result, CollapsedBorderValue(&section()->style()->borderRight(), BROWGROUP));
        if (!result.exists())
            return result;
    }
    
    // (5) Our column and column group's right borders.
    bool startColEdge;
    bool endColEdge;
    RenderTableCol* colElt = tableElt->colElement(col() + (rtl ? 0 : colSpan() - 1), &startColEdge, &endColEdge);
    if (colElt && (!rtl ? endColEdge : startColEdge)) {
        result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderRight(), BCOL));
        if (!result.exists())
            return result;
        if (colElt->parent()->isTableCol() && (!rtl ? !colElt->nextSibling() : !colElt->previousSibling())) {
            result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderRight(), BCOLGROUP));
            if (!result.exists())
                return result;
        }
    }
    
    // (6) The left border of the column to the right.
    if (!rightmostColumn) {
        colElt = tableElt->colElement(col() + (rtl ? -1 : colSpan()), &startColEdge, &endColEdge);
        if (colElt && (!rtl ? startColEdge : endColEdge)) {
            result = rtl ? compareBorders(CollapsedBorderValue(&colElt->style()->borderLeft(), BCOL), result) : compareBorders(result, CollapsedBorderValue(&colElt->style()->borderLeft(), BCOL));
            if (!result.exists())
                return result;
        }
    } else {
        // (7) The table's right border.
        result = compareBorders(result, CollapsedBorderValue(&tableElt->style()->borderRight(), BTABLE));
        if (!result.exists())
            return result;
    }
    
    return result;
}