root/Source/core/rendering/RenderFrameSet.cpp

DEFINITIONS

1. m_isChildResizing
2. frameSet
3. borderStartEdgeColor
4. borderEndEdgeColor
5. borderFillColor
6. paintColumnBorder
7. paintRowBorder
8. paint
9. resize
10. layOutAxis
11. notifyFrameEdgeInfoChanged
12. fillFromEdgeInfo
13. computeEdgeInfo
14. edgeInfo
15. layout
16. clearNeedsLayoutOnHiddenFrames
17. positionFrames
18. startResizing
19. continueResizing
20. userResize
21. setIsResizing
22. isResizingRow
23. isResizingColumn
24. canResizeRow
25. canResizeColumn
26. splitPosition
27. hitTestSplit
28. isChildAllowed
29. getCursor

/**
 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
 *           (C) 2000 Simon Hausmann <hausmann@kde.org>
 *           (C) 2000 Stefan Schimanski (1Stein@gmx.de)
 * Copyright (C) 2004, 2005, 2006 Apple Computer, Inc.
 *
 * 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
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * 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 "core/rendering/RenderFrameSet.h"

#include "core/dom/Document.h"
#include "core/events/MouseEvent.h"
#include "core/frame/LocalFrame.h"
#include "core/html/HTMLDimension.h"
#include "core/html/HTMLFrameSetElement.h"
#include "core/page/EventHandler.h"
#include "core/rendering/GraphicsContextAnnotator.h"
#include "core/rendering/LayoutRectRecorder.h"
#include "core/rendering/PaintInfo.h"
#include "core/rendering/RenderFrame.h"
#include "core/rendering/RenderView.h"
#include "platform/Cursor.h"
#include "platform/graphics/GraphicsContext.h"

namespace WebCore {

RenderFrameSet::RenderFrameSet(HTMLFrameSetElement* frameSet)
    : RenderBox(frameSet)
    , m_isResizing(false)
    , m_isChildResizing(false)
{
    setInline(false);
}

RenderFrameSet::~RenderFrameSet()
{
}

RenderFrameSet::GridAxis::GridAxis()
    : m_splitBeingResized(noSplit)
{
}

inline HTMLFrameSetElement* RenderFrameSet::frameSet() const
{
    return toHTMLFrameSetElement(node());
}

static Color borderStartEdgeColor()
{
    return Color(170, 170, 170);
}

static Color borderEndEdgeColor()
{
    return Color::black;
}

static Color borderFillColor()
{
    return Color(208, 208, 208);
}

void RenderFrameSet::paintColumnBorder(const PaintInfo& paintInfo, const IntRect& borderRect)
{
    if (!paintInfo.rect.intersects(borderRect))
        return;

    // FIXME: We should do something clever when borders from distinct framesets meet at a join.

    // Fill first.
    GraphicsContext* context = paintInfo.context;
    context->fillRect(borderRect, frameSet()->hasBorderColor() ? resolveColor(CSSPropertyBorderLeftColor) : borderFillColor());

    // Now stroke the edges but only if we have enough room to paint both edges with a little
    // bit of the fill color showing through.
    if (borderRect.width() >= 3) {
        context->fillRect(IntRect(borderRect.location(), IntSize(1, height())), borderStartEdgeColor());
        context->fillRect(IntRect(IntPoint(borderRect.maxX() - 1, borderRect.y()), IntSize(1, height())), borderEndEdgeColor());
    }
}

void RenderFrameSet::paintRowBorder(const PaintInfo& paintInfo, const IntRect& borderRect)
{
    if (!paintInfo.rect.intersects(borderRect))
        return;

    // FIXME: We should do something clever when borders from distinct framesets meet at a join.

    // Fill first.
    GraphicsContext* context = paintInfo.context;
    context->fillRect(borderRect, frameSet()->hasBorderColor() ? resolveColor(CSSPropertyBorderLeftColor) : borderFillColor());

    // Now stroke the edges but only if we have enough room to paint both edges with a little
    // bit of the fill color showing through.
    if (borderRect.height() >= 3) {
        context->fillRect(IntRect(borderRect.location(), IntSize(width(), 1)), borderStartEdgeColor());
        context->fillRect(IntRect(IntPoint(borderRect.x(), borderRect.maxY() - 1), IntSize(width(), 1)), borderEndEdgeColor());
    }
}

void RenderFrameSet::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
{
    ANNOTATE_GRAPHICS_CONTEXT(paintInfo, this);

    if (paintInfo.phase != PaintPhaseForeground)
        return;

    RenderObject* child = firstChild();
    if (!child)
        return;

    LayoutPoint adjustedPaintOffset = paintOffset + location();

    size_t rows = m_rows.m_sizes.size();
    size_t cols = m_cols.m_sizes.size();
    LayoutUnit borderThickness = frameSet()->border();

    LayoutUnit yPos = 0;
    for (size_t r = 0; r < rows; r++) {
        LayoutUnit xPos = 0;
        for (size_t c = 0; c < cols; c++) {
            child->paint(paintInfo, adjustedPaintOffset);
            xPos += m_cols.m_sizes[c];
            if (borderThickness && m_cols.m_allowBorder[c + 1]) {
                paintColumnBorder(paintInfo, pixelSnappedIntRect(LayoutRect(adjustedPaintOffset.x() + xPos, adjustedPaintOffset.y() + yPos, borderThickness, height())));
                xPos += borderThickness;
            }
            child = child->nextSibling();
            if (!child)
                return;
        }
        yPos += m_rows.m_sizes[r];
        if (borderThickness && m_rows.m_allowBorder[r + 1]) {
            paintRowBorder(paintInfo, pixelSnappedIntRect(LayoutRect(adjustedPaintOffset.x(), adjustedPaintOffset.y() + yPos, width(), borderThickness)));
            yPos += borderThickness;
        }
    }
}

void RenderFrameSet::GridAxis::resize(int size)
{
    m_sizes.resize(size);
    m_deltas.resize(size);
    m_deltas.fill(0);

    // To track edges for resizability and borders, we need to be (size + 1). This is because a parent frameset
    // may ask us for information about our left/top/right/bottom edges in order to make its own decisions about
    // what to do. We are capable of tainting that parent frameset's borders, so we have to cache this info.
    m_preventResize.resize(size + 1);
    m_allowBorder.resize(size + 1);
}

void RenderFrameSet::layOutAxis(GridAxis& axis, const Vector<HTMLDimension>& grid, int availableLen)
{
    availableLen = max(availableLen, 0);

    int* gridLayout = axis.m_sizes.data();

    if (grid.isEmpty()) {
        gridLayout[0] = availableLen;
        return;
    }

    int gridLen = axis.m_sizes.size();
    ASSERT(gridLen);

    int totalRelative = 0;
    int totalFixed = 0;
    int totalPercent = 0;
    int countRelative = 0;
    int countFixed = 0;
    int countPercent = 0;

    // First we need to investigate how many columns of each type we have and
    // how much space these columns are going to require.
    for (int i = 0; i < gridLen; ++i) {
        // Count the total length of all of the fixed columns/rows -> totalFixed
        // Count the number of columns/rows which are fixed -> countFixed
        if (grid[i].isAbsolute()) {
            gridLayout[i] = max<int>(grid[i].value(), 0);
            totalFixed += gridLayout[i];
            countFixed++;
        }

        // Count the total percentage of all of the percentage columns/rows -> totalPercent
        // Count the number of columns/rows which are percentages -> countPercent
        if (grid[i].isPercentage()) {
            gridLayout[i] = max<int>(grid[i].value() * availableLen / 100., 0);
            totalPercent += gridLayout[i];
            countPercent++;
        }

        // Count the total relative of all the relative columns/rows -> totalRelative
        // Count the number of columns/rows which are relative -> countRelative
        if (grid[i].isRelative()) {
            totalRelative += max<int>(grid[i].value(), 1);
            countRelative++;
        }
    }

    int remainingLen = availableLen;

    // Fixed columns/rows are our first priority. If there is not enough space to fit all fixed
    // columns/rows we need to proportionally adjust their size.
    if (totalFixed > remainingLen) {
        int remainingFixed = remainingLen;

        for (int i = 0; i < gridLen; ++i) {
            if (grid[i].isAbsolute()) {
                gridLayout[i] = (gridLayout[i] * remainingFixed) / totalFixed;
                remainingLen -= gridLayout[i];
            }
        }
    } else
        remainingLen -= totalFixed;

    // Percentage columns/rows are our second priority. Divide the remaining space proportionally
    // over all percentage columns/rows. IMPORTANT: the size of each column/row is not relative
    // to 100%, but to the total percentage. For example, if there are three columns, each of 75%,
    // and the available space is 300px, each column will become 100px in width.
    if (totalPercent > remainingLen) {
        int remainingPercent = remainingLen;

        for (int i = 0; i < gridLen; ++i) {
            if (grid[i].isPercentage()) {
                gridLayout[i] = (gridLayout[i] * remainingPercent) / totalPercent;
                remainingLen -= gridLayout[i];
            }
        }
    } else
        remainingLen -= totalPercent;

    // Relative columns/rows are our last priority. Divide the remaining space proportionally
    // over all relative columns/rows. IMPORTANT: the relative value of 0* is treated as 1*.
    if (countRelative) {
        int lastRelative = 0;
        int remainingRelative = remainingLen;

        for (int i = 0; i < gridLen; ++i) {
            if (grid[i].isRelative()) {
                gridLayout[i] = (max(grid[i].value(), 1.) * remainingRelative) / totalRelative;
                remainingLen -= gridLayout[i];
                lastRelative = i;
            }
        }

        // If we could not evenly distribute the available space of all of the relative
        // columns/rows, the remainder will be added to the last column/row.
        // For example: if we have a space of 100px and three columns (*,*,*), the remainder will
        // be 1px and will be added to the last column: 33px, 33px, 34px.
        if (remainingLen) {
            gridLayout[lastRelative] += remainingLen;
            remainingLen = 0;
        }
    }

    // If we still have some left over space we need to divide it over the already existing
    // columns/rows
    if (remainingLen) {
        // Our first priority is to spread if over the percentage columns. The remaining
        // space is spread evenly, for example: if we have a space of 100px, the columns
        // definition of 25%,25% used to result in two columns of 25px. After this the
        // columns will each be 50px in width.
        if (countPercent && totalPercent) {
            int remainingPercent = remainingLen;
            int changePercent = 0;

            for (int i = 0; i < gridLen; ++i) {
                if (grid[i].isPercentage()) {
                    changePercent = (remainingPercent * gridLayout[i]) / totalPercent;
                    gridLayout[i] += changePercent;
                    remainingLen -= changePercent;
                }
            }
        } else if (totalFixed) {
            // Our last priority is to spread the remaining space over the fixed columns.
            // For example if we have 100px of space and two column of each 40px, both
            // columns will become exactly 50px.
            int remainingFixed = remainingLen;
            int changeFixed = 0;

            for (int i = 0; i < gridLen; ++i) {
                if (grid[i].isAbsolute()) {
                    changeFixed = (remainingFixed * gridLayout[i]) / totalFixed;
                    gridLayout[i] += changeFixed;
                    remainingLen -= changeFixed;
                }
            }
        }
    }

    // If we still have some left over space we probably ended up with a remainder of
    // a division. We cannot spread it evenly anymore. If we have any percentage
    // columns/rows simply spread the remainder equally over all available percentage columns,
    // regardless of their size.
    if (remainingLen && countPercent) {
        int remainingPercent = remainingLen;
        int changePercent = 0;

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

        for (int i = 0; i < gridLen; ++i) {
            if (grid[i].isAbsolute()) {
                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::notifyFrameEdgeInfoChanged()
{
    if (needsLayout())
        return;
    // FIXME: We should only recompute the edge info with respect to the frame that changed
    // and its adjacent frame(s) instead of recomputing the edge info for the entire frameset.
    computeEdgeInfo();
}

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;

    size_t rows = m_rows.m_sizes.size();
    size_t cols = m_cols.m_sizes.size();
    for (size_t r = 0; r < rows; ++r) {
        for (size_t c = 0; c < cols; ++c) {
            FrameEdgeInfo edgeInfo;
            if (child->isFrameSet())
                edgeInfo = toRenderFrameSet(child)->edgeInfo();
            else
                edgeInfo = toRenderFrame(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());

    LayoutRectRecorder recorder(*this);
    bool doFullRepaint = selfNeedsLayout() && checkForRepaintDuringLayout();
    LayoutRect oldBounds;
    RenderLayerModelObject* repaintContainer = 0;
    if (doFullRepaint) {
        repaintContainer = containerForRepaint();
        oldBounds = clippedOverflowRectForRepaint(repaintContainer);
    }

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

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

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

    LayoutUnit 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();

    updateLayerTransform();

    if (doFullRepaint) {
        repaintUsingContainer(repaintContainer, pixelSnappedIntRect(oldBounds), InvalidationSelfLayout);
        LayoutRect newBounds = clippedOverflowRectForRepaint(repaintContainer);
        if (newBounds != oldBounds)
            repaintUsingContainer(repaintContainer, pixelSnappedIntRect(newBounds), InvalidationSelfLayout);
    }

    clearNeedsLayout();
}

static void clearNeedsLayoutOnHiddenFrames(RenderBox* frame)
{
    for (; frame; frame = frame->nextSiblingBox()) {
        frame->setWidth(0);
        frame->setHeight(0);
        frame->clearNeedsLayout();
        clearNeedsLayoutOnHiddenFrames(frame->firstChildBox());
    }
}

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(IntPoint(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();
                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.
    clearNeedsLayoutOnHiddenFrames(child);
}

void RenderFrameSet::startResizing(GridAxis& axis, int position)
{
    int split = hitTestSplit(axis, position);
    if (split == noSplit || 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)
        return;
    axis.m_deltas[axis.m_splitBeingResized - 1] += delta;
    axis.m_deltas[axis.m_splitBeingResized] -= delta;
    setNeedsLayout();
}

bool RenderFrameSet::userResize(MouseEvent* evt)
{
    if (!m_isResizing) {
        if (needsLayout())
            return false;
        if (evt->type() == EventTypeNames::mousedown && evt->button() == LeftButton) {
            FloatPoint localPos = absoluteToLocal(evt->absoluteLocation(), UseTransforms);
            startResizing(m_cols, localPos.x());
            startResizing(m_rows, localPos.y());
            if (m_cols.m_splitBeingResized != noSplit || m_rows.m_splitBeingResized != noSplit) {
                setIsResizing(true);
                return true;
            }
        }
    } else {
        if (evt->type() == EventTypeNames::mousemove || (evt->type() == EventTypeNames::mouseup && evt->button() == LeftButton)) {
            FloatPoint localPos = absoluteToLocal(evt->absoluteLocation(), UseTransforms);
            continueResizing(m_cols, localPos.x());
            continueResizing(m_rows, localPos.y());
            if (evt->type() == EventTypeNames::mouseup && evt->button() == LeftButton) {
                setIsResizing(false);
                return true;
            }
        }
    }

    return false;
}

void RenderFrameSet::setIsResizing(bool isResizing)
{
    m_isResizing = isResizing;
    for (RenderObject* ancestor = parent(); ancestor; ancestor = ancestor->parent()) {
        if (ancestor->isFrameSet())
            toRenderFrameSet(ancestor)->m_isChildResizing = isResizing;
    }
    if (LocalFrame* frame = this->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_preventResize[r];
}

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

CursorDirective RenderFrameSet::getCursor(const LayoutPoint& point, Cursor& cursor) const
{
    IntPoint roundedPoint = roundedIntPoint(point);
    if (canResizeRow(roundedPoint)) {
        cursor = rowResizeCursor();
        return SetCursor;
    }
    if (canResizeColumn(roundedPoint)) {
        cursor = columnResizeCursor();
        return SetCursor;
    }
    return RenderBox::getCursor(point, cursor);
}

} // namespace WebCore