renderframeset.cpp

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        for (int i = 0; i < gridLen; ++i) {
            if (grid[i].isPercent()) {
                changePercent = remainingPercent / countPercent;
                gridLayout[i] += changePercent;
                remainingLen -= changePercent;
            }
        }
    } 
    
    // If we don't have any percentage columns/rows we only have fixed columns. Spread
    // the remainder equally over all fixed columns/rows.
    else if (remainingLen && countFixed) {
        int remainingFixed = remainingLen;
        int changeFixed = 0;
        
        for (int i = 0; i < gridLen; ++i) {
            if (grid[i].isFixed()) {
                changeFixed = remainingFixed / countFixed;
                gridLayout[i] += changeFixed;
                remainingLen -= changeFixed;
            }
        }
    }

    // Still some left over. Add it to the last column, because it is impossible
    // spread it evenly or equally.
    if (remainingLen)
        gridLayout[gridLen - 1] += remainingLen;

    // now we have the final layout, distribute the delta over it
    bool worked = true;
    int* gridDelta = axis.m_deltas.data();
    for (int i = 0; i < gridLen; ++i) {
        if (gridLayout[i] && gridLayout[i] + gridDelta[i] <= 0)
            worked = false;
        gridLayout[i] += gridDelta[i];
    }
    // if the deltas broke something, undo them
    if (!worked) {
        for (int i = 0; i < gridLen; ++i)
            gridLayout[i] -= gridDelta[i];
        axis.m_deltas.fill(0);
    }
}

void RenderFrameSet::fillFromEdgeInfo(const FrameEdgeInfo& edgeInfo, int r, int c)
{
    if (edgeInfo.allowBorder(LeftFrameEdge))
        m_cols.m_allowBorder[c] = true;
    if (edgeInfo.allowBorder(RightFrameEdge))
        m_cols.m_allowBorder[c + 1] = true;
    if (edgeInfo.preventResize(LeftFrameEdge))
        m_cols.m_preventResize[c] = true;
    if (edgeInfo.preventResize(RightFrameEdge))
        m_cols.m_preventResize[c + 1] = true;
    
    if (edgeInfo.allowBorder(TopFrameEdge))
        m_rows.m_allowBorder[r] = true;
    if (edgeInfo.allowBorder(BottomFrameEdge))
        m_rows.m_allowBorder[r + 1] = true;
    if (edgeInfo.preventResize(TopFrameEdge))
        m_rows.m_preventResize[r] = true;
    if (edgeInfo.preventResize(BottomFrameEdge))
        m_rows.m_preventResize[r + 1] = true;
}

void RenderFrameSet::computeEdgeInfo()
{
    m_rows.m_preventResize.fill(frameSet()->noResize());    
    m_rows.m_allowBorder.fill(false);
    m_cols.m_preventResize.fill(frameSet()->noResize());    
    m_cols.m_allowBorder.fill(false);
    
    RenderObject* child = firstChild();
    if (!child)
        return;

    int rows = frameSet()->totalRows();
    int cols = frameSet()->totalCols();
    for (int r = 0; r < rows; ++r) {
        for (int c = 0; c < cols; ++c) {
            FrameEdgeInfo edgeInfo;
            if (child->isFrameSet())
                edgeInfo = static_cast<RenderFrameSet*>(child)->edgeInfo();
            else
                edgeInfo = static_cast<RenderFrame*>(child)->edgeInfo();
            fillFromEdgeInfo(edgeInfo, r, c);
            child = child->nextSibling();
            if (!child)
                return;
        }
    }
}

FrameEdgeInfo RenderFrameSet::edgeInfo() const
{
    FrameEdgeInfo result(frameSet()->noResize(), true);
    
    int rows = frameSet()->totalRows();
    int cols = frameSet()->totalCols();
    if (rows && cols) {
        result.setPreventResize(LeftFrameEdge, m_cols.m_preventResize[0]);
        result.setAllowBorder(LeftFrameEdge, m_cols.m_allowBorder[0]);
        result.setPreventResize(RightFrameEdge, m_cols.m_preventResize[cols]);
        result.setAllowBorder(RightFrameEdge, m_cols.m_allowBorder[cols]);
        result.setPreventResize(TopFrameEdge, m_rows.m_preventResize[0]);
        result.setAllowBorder(TopFrameEdge, m_rows.m_allowBorder[0]);
        result.setPreventResize(BottomFrameEdge, m_rows.m_preventResize[rows]);
        result.setAllowBorder(BottomFrameEdge, m_rows.m_allowBorder[rows]);
    }
    
    return result;
}

void RenderFrameSet::layout()
{
    ASSERT(needsLayout());

    bool doFullRepaint = selfNeedsLayout() && checkForRepaintDuringLayout();
    IntRect oldBounds;
    if (doFullRepaint)
        oldBounds = absoluteClippedOverflowRect();

    if (!parent()->isFrameSet() && !document()->printing()) {
        setWidth(view()->viewWidth());
        setHeight(view()->viewHeight());
    }

    size_t cols = frameSet()->totalCols();
    size_t rows = frameSet()->totalRows();

    if (m_rows.m_sizes.size() != rows || m_cols.m_sizes.size() != cols) {
        m_rows.resize(rows);
        m_cols.resize(cols);
    }

    int borderThickness = frameSet()->border();
    layOutAxis(m_rows, frameSet()->rowLengths(), height() - (rows - 1) * borderThickness);
    layOutAxis(m_cols, frameSet()->colLengths(), width() - (cols - 1) * borderThickness);

    positionFrames();

    RenderBox::layout();

    computeEdgeInfo();

    if (doFullRepaint) {
        view()->repaintViewRectangle(oldBounds);
        IntRect newBounds = absoluteClippedOverflowRect();
        if (newBounds != oldBounds)
            view()->repaintViewRectangle(newBounds);
    }

    setNeedsLayout(false);
}

void RenderFrameSet::positionFrames()
{
    RenderBox* child = firstChildBox();
    if (!child)
        return;

    int rows = frameSet()->totalRows();
    int cols = frameSet()->totalCols();

    int yPos = 0;
    int borderThickness = frameSet()->border();
    for (int r = 0; r < rows; r++) {
        int xPos = 0;
        int height = m_rows.m_sizes[r];
        for (int c = 0; c < cols; c++) {
            child->setLocation(xPos, yPos);
            int width = m_cols.m_sizes[c];

            // has to be resized and itself resize its contents
            if (width != child->width() || height != child->height()) {
                child->setWidth(width);
                child->setHeight(height);
                child->setNeedsLayout(true);
                child->layout();
            }

            xPos += width + borderThickness;

            child = child->nextSiblingBox();
            if (!child)
                return;
        }
        yPos += height + borderThickness;
    }

    // all the remaining frames are hidden to avoid ugly spurious unflowed frames
    for (; child; child = child->nextSiblingBox()) {
        child->setWidth(0);
        child->setHeight(0);
        child->setNeedsLayout(false);
    }
}

void RenderFrameSet::startResizing(GridAxis& axis, int position)
{
    int split = hitTestSplit(axis, position);
    if (split == noSplit || !axis.m_allowBorder[split] || axis.m_preventResize[split]) {
        axis.m_splitBeingResized = noSplit;
        return;
    }
    axis.m_splitBeingResized = split;
    axis.m_splitResizeOffset = position - splitPosition(axis, split);
}

void RenderFrameSet::continueResizing(GridAxis& axis, int position)
{
    if (needsLayout())
        return;
    if (axis.m_splitBeingResized == noSplit)
        return;
    int currentSplitPosition = splitPosition(axis, axis.m_splitBeingResized);
    int delta = (position - currentSplitPosition) - axis.m_splitResizeOffset;
    if (delta == 0)
        return;
    axis.m_deltas[axis.m_splitBeingResized - 1] += delta;
    axis.m_deltas[axis.m_splitBeingResized] -= delta;
    setNeedsLayout(true);
}

bool RenderFrameSet::userResize(MouseEvent* evt)
{
    if (!m_isResizing) {
        if (needsLayout())
            return false;
        if (evt->type() == eventNames().mousedownEvent && evt->button() == LeftButton) {
            FloatPoint pos = localToAbsolute();
            startResizing(m_cols, evt->pageX() - pos.x());
            startResizing(m_rows, evt->pageY() - pos.y());
            if (m_cols.m_splitBeingResized != noSplit || m_rows.m_splitBeingResized != noSplit) {
                setIsResizing(true);
                return true;
            }
        }
    } else {
        if (evt->type() == eventNames().mousemoveEvent || (evt->type() == eventNames().mouseupEvent && evt->button() == LeftButton)) {
            FloatPoint pos = localToAbsolute();
            continueResizing(m_cols, evt->pageX() - pos.x());
            continueResizing(m_rows, evt->pageY() - pos.y());
            if (evt->type() == eventNames().mouseupEvent && evt->button() == LeftButton) {
                setIsResizing(false);
                return true;
            }
        }
    }

    return false;
}

void RenderFrameSet::setIsResizing(bool isResizing)
{
    m_isResizing = isResizing;
    for (RenderObject* p = parent(); p; p = p->parent())
        if (p->isFrameSet())
            static_cast<RenderFrameSet*>(p)->m_isChildResizing = isResizing;
    if (Frame* frame = document()->frame())
        frame->eventHandler()->setResizingFrameSet(isResizing ? frameSet() : 0);
}

bool RenderFrameSet::isResizingRow() const
{
    return m_isResizing && m_rows.m_splitBeingResized != noSplit;
}

bool RenderFrameSet::isResizingColumn() const
{
    return m_isResizing && m_cols.m_splitBeingResized != noSplit;
}

bool RenderFrameSet::canResizeRow(const IntPoint& p) const
{
    int r = hitTestSplit(m_rows, p.y());
    return r != noSplit && m_rows.m_allowBorder[r] && !m_rows.m_preventResize[r];
}

bool RenderFrameSet::canResizeColumn(const IntPoint& p) const
{
    int c = hitTestSplit(m_cols, p.x());
    return c != noSplit && m_cols.m_allowBorder[c] && !m_cols.m_preventResize[c];
}

int RenderFrameSet::splitPosition(const GridAxis& axis, int split) const
{
    if (needsLayout())
        return 0;

    int borderThickness = frameSet()->border();

    int size = axis.m_sizes.size();
    if (!size)
        return 0;

    int position = 0;
    for (int i = 0; i < split && i < size; ++i)
        position += axis.m_sizes[i] + borderThickness;
    return position - borderThickness;
}

int RenderFrameSet::hitTestSplit(const GridAxis& axis, int position) const
{
    if (needsLayout())
        return noSplit;

    int borderThickness = frameSet()->border();
    if (borderThickness <= 0)
        return noSplit;

    size_t size = axis.m_sizes.size();
    if (!size)
        return noSplit;

    int splitPosition = axis.m_sizes[0];
    for (size_t i = 1; i < size; ++i) {
        if (position >= splitPosition && position < splitPosition + borderThickness)
            return i;
        splitPosition += borderThickness + axis.m_sizes[i];
    }
    return noSplit;
}

bool RenderFrameSet::isChildAllowed(RenderObject* child, RenderStyle*) const
{
    return child->isFrame() || child->isFrameSet();
}

} // namespace WebCore