render_layer.cpp

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

/*
 * Copyright (C) 2003 Apple Computer, Inc.
 *
 * Portions are Copyright (C) 1998 Netscape Communications Corporation.
 *
 * Other contributors:
 *   Robert O'Callahan <[e-mail]>
 *   David Baron <[e-mail]>
 *   Christian Biesinger <[e-mail]>
 *   Randall Jesup <[e-mail]>
 *   Roland Mainz <[e-mail]>
 *   Josh Soref <[e-mail]>
 *   Boris Zbarsky <[e-mail]>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Alternatively, the contents of this file may be used under the terms
 * of either the Mozilla Public License Version 1.1, found at
 * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public
 * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html
 * (the "GPL"), in which case the provisions of the MPL or the GPL are
 * applicable instead of those above.  If you wish to allow use of your
 * version of this file only under the terms of one of those two
 * licenses (the MPL or the GPL) and not to allow others to use your
 * version of this file under the LGPL, indicate your decision by
 * deletingthe provisions above and replace them with the notice and
 * other provisions required by the MPL or the GPL, as the case may be.
 * If you do not delete the provisions above, a recipient may use your
 * version of this file under any of the LGPL, the MPL or the GPL.
 */

//#define BOX_DEBUG

#include "render_layer.h"
#include <kdebug.h>
#include <assert.h>
#include "khtmlview.h"
#include "render_canvas.h"
#include "render_arena.h"
#include "render_replaced.h"
#include "xml/dom_docimpl.h"
#include "xml/dom2_eventsimpl.h"
#include "misc/htmltags.h"
#include "html/html_blockimpl.h"

#include <qscrollbar.h>
#include <qptrvector.h>
#include <qstyle.h>

using namespace DOM;
using namespace khtml;

#ifdef APPLE_CHANGES
QScrollBar* RenderLayer::gScrollBar = 0;
#endif

#ifndef NDEBUG
static bool inRenderLayerDetach;
#endif

void
RenderScrollMediator::slotValueChanged()
{
    m_layer->updateScrollPositionFromScrollbars();
}

RenderLayer::RenderLayer(RenderObject* object)
: m_object( object ),
m_parent( 0 ),
m_previous( 0 ),
m_next( 0 ),
m_first( 0 ),
m_last( 0 ),
m_x( 0 ),
m_y( 0 ),
m_scrollX( 0 ),
m_scrollY( 0 ),
m_scrollWidth( 0 ),
m_scrollHeight( 0 ),
m_hBar( 0 ),
m_vBar( 0 ),
m_scrollMediator( 0 ),
m_posZOrderList( 0 ),
m_negZOrderList( 0 ),
m_zOrderListsDirty( true ),
m_markedForRepaint( false ),
m_marquee( 0 )
{
}

RenderLayer::~RenderLayer()
{
    // Child layers will be deleted by their corresponding render objects, so
    // our destructor doesn't have to do anything.
    delete m_hBar;
    delete m_vBar;
    delete m_scrollMediator;
    delete m_posZOrderList;
    delete m_negZOrderList;
    delete m_marquee;
}

void RenderLayer::updateLayerPosition()
{
    // The canvas is sized to the docWidth/Height over in RenderCanvas::layout, so we
    // don't need to ever update our layer position here.
    if (renderer()->isCanvas())
        return;

    int x = m_object->xPos();
    int y = m_object->yPos();

    if (!m_object->isPositioned()) {
        // We must adjust our position by walking up the render tree looking for the
        // nearest enclosing object with a layer.
        RenderObject* curr = m_object->parent();
        while (curr && !curr->layer()) {
            x += curr->xPos();
            y += curr->yPos();
            curr = curr->parent();
        }
    }

    if (m_object->isRelPositioned())
        static_cast<RenderBox*>(m_object)->relativePositionOffset(x, y);

    // Subtract our parent's scroll offset.
    if (m_object->isPositioned() && enclosingPositionedAncestor()) {
        RenderLayer* positionedParent = enclosingPositionedAncestor();

        // For positioned layers, we subtract out the enclosing positioned layer's scroll offset.
        positionedParent->subtractScrollOffset(x, y);
        
        if (positionedParent->renderer()->isRelPositioned() &&
            positionedParent->renderer()->isInlineFlow()) {
            // When we have an enclosing relpositioned inline, we need to add in the offset of the first line
            // box from the rest of the content, but only in the cases where we know we're positioned
            // relative to the inline itself.
            RenderFlow* flow = static_cast<RenderFlow*>(positionedParent->renderer());
            int sx = 0, sy = 0;
            if (flow->firstLineBox()) {
                if (flow->style()->direction() == LTR)
                    sx = flow->firstLineBox()->xPos();
                else
                    sx = flow->lastLineBox()->xPos();
                sy = flow->firstLineBox()->yPos();
            } else {
                sx = flow->staticX(); // ###
                sy = flow->staticY();
            }
            bool isInlineType = m_object->style()->isOriginalDisplayInlineType();
            
            if (!m_object->hasStaticX())
                x += sx;
            
            // This is not terribly intuitive, but we have to match other browsers.  Despite being a block display type inside
            // an inline, we still keep our x locked to the left of the relative positioned inline.  Arguably the correct
            // behavior would be to go flush left to the block that contains the inline, but that isn't what other browsers
            // do.
            if (m_object->hasStaticX() && !isInlineType)
                // Avoid adding in the left border/padding of the containing block twice.  Subtract it out.
                x += sx - (m_object->containingBlock()->borderLeft() + m_object->containingBlock()->paddingLeft());
            
            if (!m_object->hasStaticY())
                y += sy;
        }
    }
    else if (parent())
        parent()->subtractScrollOffset(x, y);

    setPos(x,y);
}

void RenderLayer::repaint( bool markForRepaint )
{
    if (markForRepaint && m_markedForRepaint)
        return;
    for (RenderLayer* child = firstChild(); child; child = child->nextSibling())
        child->repaint( markForRepaint );
    QRect layerBounds, damageRect, fgrect;
    calculateRects(renderer()->canvas()->layer(), renderer()->viewRect(), layerBounds, damageRect, fgrect);
    m_visibleRect = damageRect.intersect( layerBounds );
    if (m_visibleRect.isValid())
        renderer()->canvas()->repaintViewRectangle( m_visibleRect.x(), m_visibleRect.y(), m_visibleRect.width(), m_visibleRect.height() );
    if (markForRepaint)
        m_markedForRepaint = true;
}

void RenderLayer::updateLayerPositions(RenderLayer* rootLayer, bool doFullRepaint, bool checkForRepaint)
{
    if (doFullRepaint) {
        m_object->repaint();
        checkForRepaint = doFullRepaint = false;
    }
    
    updateLayerPosition(); // For relpositioned layers or non-positioned layers,
                           // we need to keep in sync, since we may have shifted relative
                           // to our parent layer.

    if (m_hBar || m_vBar) {
        // Need to position the scrollbars.
        int x = 0;
        int y = 0;
        convertToLayerCoords(rootLayer, x, y);
        QRect layerBounds = QRect(x,y,width(),height());
        positionScrollbars(layerBounds);
    }

#ifdef APPLE_CHANGES
    // FIXME: Child object could override visibility.
    if (checkForRepaint && (m_object->style()->visibility() == VISIBLE))
        m_object->repaintAfterLayoutIfNeeded(m_repaintRect, m_fullRepaintRect);
#else    
    if (checkForRepaint && m_markedForRepaint) {
        QRect layerBounds, damageRect, fgrect;
        calculateRects(rootLayer, renderer()->viewRect(), layerBounds, damageRect, fgrect);
        QRect vr = damageRect.intersect( layerBounds );
        if (vr != m_visibleRect && vr.isValid())
            renderer()->canvas()->repaintViewRectangle( vr.x(), vr.y(), vr.width(), vr.height() );
    }
    m_markedForRepaint = false;   
#endif
    
    for	(RenderLayer* child = firstChild(); child; child = child->nextSibling())
        child->updateLayerPositions(rootLayer, doFullRepaint, checkForRepaint);
        
    // With all our children positioned, now update our marquee if we need to.
    if (m_marquee)
        m_marquee->updateMarqueePosition();
}


short RenderLayer::width() const
{
    int w = m_object->width();
    if (!m_object->style()->hidesOverflow())
        w = kMax(m_object->overflowWidth(), w);
    return w;
}

int RenderLayer::height() const
{
    int h = m_object->height();
    if (!m_object->style()->hidesOverflow())
        h = kMax(m_object->overflowHeight(), h);
    return h;
}


RenderLayer *RenderLayer::stackingContext() const
{
    RenderLayer* curr = parent();
    for ( ; curr && !curr->m_object->isCanvas() &&
          curr->m_object->style()->hasAutoZIndex();
          curr = curr->parent());
    return curr;
}

RenderLayer* RenderLayer::enclosingPositionedAncestor() const
{
    RenderLayer* curr = parent();
    for ( ; curr && !curr->m_object->isCanvas() &&
         !curr->m_object->isPositioned() && !curr->m_object->isRelPositioned();
         curr = curr->parent());

    return curr;
}

#ifdef APPLE_CHANGES
bool RenderLayer::isTransparent()
{
    return m_object->style()->opacity() < 1.0f;
}

RenderLayer* RenderLayer::transparentAncestor()
{
    RenderLayer* curr = parent();
    for ( ; curr && curr->m_object->style()->opacity() == 1.0f; curr = curr->parent());
    return curr;
}
#endif

void* RenderLayer::operator new(size_t sz, RenderArena* renderArena) throw()
{
    return renderArena->allocate(sz);
}

void RenderLayer::operator delete(void* ptr, size_t sz)
{
    assert(inRenderLayerDetach);

    // Stash size where detach can find it.
    *(size_t *)ptr = sz;
}

void RenderLayer::detach(RenderArena* renderArena)
{
#ifndef NDEBUG
    inRenderLayerDetach = true;
#endif
    delete this;
#ifndef NDEBUG
    inRenderLayerDetach = false;
#endif

    // Recover the size left there for us by operator delete and free the memory.
    renderArena->free(*(size_t *)this, this);
}

void RenderLayer::addChild(RenderLayer *child, RenderLayer* beforeChild)
{
    RenderLayer* prevSibling = beforeChild ? beforeChild->previousSibling() : lastChild();
    if (prevSibling) {
        child->setPreviousSibling(prevSibling);
        prevSibling->setNextSibling(child);
    }
    else
        setFirstChild(child);

    if (beforeChild) {
        beforeChild->setPreviousSibling(child);
        child->setNextSibling(beforeChild);
    }
    else
        setLastChild(child);

    child->setParent(this);

    // Dirty the z-order list in which we are contained.  The stackingContext() can be null in the
    // case where we're building up generated content layers.  This is ok, since the lists will start
    // off dirty in that case anyway.
    RenderLayer* stackingContext = child->stackingContext();
    if (stackingContext)
        stackingContext->dirtyZOrderLists();
}

RenderLayer* RenderLayer::removeChild(RenderLayer* oldChild)
{
    // remove the child
    if (oldChild->previousSibling())
        oldChild->previousSibling()->setNextSibling(oldChild->nextSibling());
    if (oldChild->nextSibling())
        oldChild->nextSibling()->setPreviousSibling(oldChild->previousSibling());

    if (m_first == oldChild)
        m_first = oldChild->nextSibling();
    if (m_last == oldChild)
        m_last = oldChild->previousSibling();

    // Dirty the z-order list in which we are contained.  When called via the
    // reattachment process in removeOnlyThisLayer, the layer may already be disconnected
    // from the main layer tree, so we need to null-check the |stackingContext| value.
    RenderLayer* stackingContext = oldChild->stackingContext();
    if (stackingContext)
        oldChild->stackingContext()->dirtyZOrderLists();

    oldChild->setPreviousSibling(0);
    oldChild->setNextSibling(0);
    oldChild->setParent(0);

    return oldChild;
}

void RenderLayer::removeOnlyThisLayer()
{
    if (!m_parent)
        return;

    // Remove us from the parent.
    RenderLayer* parent = m_parent;
    RenderLayer* nextSib = nextSibling();
    parent->removeChild(this);

    // Now walk our kids and reattach them to our parent.
    RenderLayer* current = m_first;
    while (current) {
        RenderLayer* next = current->nextSibling();
        removeChild(current);
        parent->addChild(current, nextSib);
        current = next;
    }

    detach(renderer()->renderArena());
}

void RenderLayer::insertOnlyThisLayer()
{
    if (!m_parent && renderer()->parent()) {
        // We need to connect ourselves when our renderer() has a parent.
        // Find our enclosingLayer and add ourselves.
        RenderLayer* parentLayer = renderer()->parent()->enclosingLayer();
        if (parentLayer)
            parentLayer->addChild(this,
                                  renderer()->parent()->findNextLayer(parentLayer, renderer()));
    }

    // Remove all descendant layers from the hierarchy and add them to the new position.
    for (RenderObject* curr = renderer()->firstChild(); curr; curr = curr->nextSibling())
        curr->moveLayers(m_parent, this);
}

void RenderLayer::convertToLayerCoords(const RenderLayer* ancestorLayer, int& x, int& y) const
{
    if (ancestorLayer == this)
        return;

    if (m_object->style()->position() == FIXED) {