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.

/**
 * This file is part of the DOM implementation for KDE.
 *
 * Copyright (C) 1999-2003 Lars Knoll ([e-mail])
 *           (C) 1999 Antti Koivisto ([e-mail])
 *           (C) 2002-2003 Apple Computer, Inc.
 *           (C) 2005 Allan Sandfeld Jensen ([e-mail])
 *
 * 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.
 *
 */
// -------------------------------------------------------------------------
//#define DEBUG_LAYOUT
//#define CLIP_DEBUG


#include <qpainter.h>

#include "misc/loader.h"
#include "rendering/render_replaced.h"
#include "rendering/render_canvas.h"
#include "rendering/render_table.h"
#include "rendering/render_inline.h"
#include "rendering/render_block.h"
#include "rendering/render_line.h"
#include "rendering/render_layer.h"
#include "misc/htmlhashes.h"
#include "xml/dom_nodeimpl.h"
#include "xml/dom_docimpl.h"
#include "html/html_elementimpl.h"

#include <khtmlview.h>
#include <kdebug.h>
#include <kglobal.h>
#include <assert.h>


using namespace DOM;
using namespace khtml;

#define TABLECELLMARGIN -0x4000

RenderBox::RenderBox(DOM::NodeImpl* node)
    : RenderContainer(node)
{
    m_minWidth = -1;
    m_maxWidth = -1;
    m_width = m_height = 0;
    m_x = 0;
    m_y = 0;
    m_marginTop = 0;
    m_marginBottom = 0;
    m_marginLeft = 0;
    m_marginRight = 0;
    m_staticX = 0;
    m_staticY = 0;

    m_placeHolderBox = 0;
    m_layer = 0;
}

RenderBlock* RenderBox::createAnonymousBlock()
{
    RenderStyle *newStyle = new RenderStyle();
    newStyle->inheritFrom(style());
    newStyle->setDisplay(BLOCK);

    RenderBlock *newBox = new (renderArena()) RenderBlock(document() /* anonymous*/);
    newBox->setStyle(newStyle);
    return newBox;
}

void RenderBox::restructureParentFlow() {
    if (!parent() || parent()->childrenInline() == isInline())
        return;
    // We have gone from not affecting the inline status of the parent flow to suddenly
    // having an impact.  See if there is a mismatch between the parent flow's
    // childrenInline() state and our state.
    if (!isInline()) {
        if (parent()->isRenderInline()) {
            // We have to split the parent flow.
            RenderInline* parentInline = static_cast<RenderInline*>(parent());
            RenderBlock* newBox = parentInline->createAnonymousBlock();

            RenderFlow* oldContinuation = parent()->continuation();
            parentInline->setContinuation(newBox);

            RenderObject* beforeChild = nextSibling();
            parent()->removeChildNode(this);
            parentInline->splitFlow(beforeChild, newBox, this, oldContinuation);
        }
        else if (parent()->isRenderBlock())
            static_cast<RenderBlock*>(parent())->makeChildrenNonInline();
    }
    else {
        // An anonymous block must be made to wrap this inline.
        RenderBlock* box = createAnonymousBlock();
        parent()->insertChildNode(box, this);
        box->appendChildNode(parent()->removeChildNode(this));
    }
}

void RenderBox::setStyle(RenderStyle *_style)
{
    bool affectsParent = style() && isFloatingOrPositioned() &&
         (!_style->isFloating() && _style->position() != ABSOLUTE && _style->position() != FIXED) &&
         parent() && (parent()->isBlockFlow() || parent()->isInlineFlow());

    RenderContainer::setStyle(_style);

    // The root always paints its background/border.
    if (isRoot())
        setShouldPaintBackgroundOrBorder(true);

    switch(_style->display())
    {
    case INLINE:
    case INLINE_BLOCK:
    case INLINE_TABLE:
        setInline(true);
        break;
    case RUN_IN:
        if (isInline() && parent() && parent()->childrenInline())
            break;
    default:
        setInline(false);
    }

    switch(_style->position())
    {
    case ABSOLUTE:
    case FIXED:
        setPositioned(true);
        break;
    default:
        setPositioned(false);
        if( !isTableCell() && _style->isFloating() )
            setFloating(true);

        if( _style->position() == RELATIVE )
            setRelPositioned(true);
    }

    if (requiresLayer()) {
        if (!m_layer) {
            m_layer = new (renderArena()) RenderLayer(this);
            m_layer->insertOnlyThisLayer();
        }
    }
    else if (m_layer && !isCanvas()) {
        m_layer->removeOnlyThisLayer();
        m_layer = 0;
    }

    if (m_layer) {
        // Make sure our z-index values are only applied if we're positioned or
        // relpositioned.
        if (!isPositioned() && !isRelPositioned()) {
            // Set the auto z-index flag.
            if (isRoot())
                style()->setZIndex(0);
            else
                style()->setHasAutoZIndex();
        }
        m_layer->styleChanged();
    }
    // ### outlineSize() and outlineOffset() not merged yet
    if (style()->outlineWidth() > 0 && style()->outlineWidth() > maximalOutlineSize(PaintActionOutline))
        static_cast<RenderCanvas*>(document()->renderer())->setMaximalOutlineSize(style()->outlineWidth());
    if (affectsParent)
        restructureParentFlow();
}

RenderBox::~RenderBox()
{
    //kdDebug( 6040 ) << "Element destructor: this=" << nodeName().string() << endl;
}

void RenderBox::detach()
{
    RenderLayer* layer = m_layer;
    RenderArena* arena = renderArena();

    RenderContainer::detach();

    if (layer)
        layer->detach(arena);
}

InlineBox* RenderBox::createInlineBox(bool /*makePlaceHolderBox*/, bool /*isRootLineBox*/)
{
    if (m_placeHolderBox)
        m_placeHolderBox->detach(renderArena());
    return (m_placeHolderBox = new (renderArena()) InlineBox(this));
}

void RenderBox::deleteInlineBoxes(RenderArena* arena)
{
    if (m_placeHolderBox) {
        m_placeHolderBox->detach( arena ? arena : renderArena() );
        m_placeHolderBox = 0;
    }
}

short RenderBox::contentWidth() const
{
    short w = m_width - style()->borderLeftWidth() - style()->borderRightWidth();
    w -= paddingLeft() + paddingRight();

    if (m_layer && style()->scrollsOverflow())
        w -= m_layer->verticalScrollbarWidth();

    //kdDebug( 6040 ) << "RenderBox::contentWidth(2) = " << w << endl;
    return w;
}

int RenderBox::contentHeight() const
{
    int h = m_height - style()->borderTopWidth() - style()->borderBottomWidth();
    h -= paddingTop() + paddingBottom();

    if (m_layer && style()->scrollsOverflow())
        h -= m_layer->horizontalScrollbarHeight();

    return h;
}

void RenderBox::setPos( int xPos, int yPos )
{
    m_x = xPos; m_y = yPos;
}

short RenderBox::width() const
{
    return m_width;
}

int RenderBox::height() const
{
    return m_height;
}

void RenderBox::setWidth( int width )
{
    m_width = width;
}

void RenderBox::setHeight( int height )
{
    m_height = height;
}

int RenderBox::calcBoxHeight(int h) const
{
    if (style()->boxSizing() == CONTENT_BOX)
        h += borderTop() + borderBottom() + paddingTop() + paddingBottom();

    return h;
}

int RenderBox::calcBoxWidth(int w) const
{
    if (style()->boxSizing() == CONTENT_BOX)
        w += borderLeft() + borderRight() + paddingLeft() + paddingRight();

    return w;
}

int RenderBox::calcContentHeight(int h) const
{
    if (style()->boxSizing() == BORDER_BOX)
        h -= borderTop() + borderBottom() + paddingTop() + paddingBottom();

    return kMax(0, h);
}

int RenderBox::calcContentWidth(int w) const
{
    if (style()->boxSizing() == BORDER_BOX)
        w -= borderLeft() + borderRight() + paddingLeft() + paddingRight();

    return kMax(0, w);
}

// --------------------- painting stuff -------------------------------

void RenderBox::paint(PaintInfo& i, int _tx, int _ty)
{
    _tx += m_x;
    _ty += m_y;

    if (style()->hidesOverflow() && m_layer)
        m_layer->subtractScrollOffset(_tx, _ty);

    // default implementation. Just pass things through to the children
    for(RenderObject* child = firstChild(); child; child = child->nextSibling())
        child->paint(i, _tx, _ty);
}

void RenderBox::paintRootBoxDecorations(PaintInfo& paintInfo, int _tx, int _ty)
{
    //kdDebug( 6040 ) << renderName() << "::paintRootBoxDecorations()" << _tx << "/" << _ty << endl;
    const BackgroundLayer* bgLayer = style()->backgroundLayers();
    QColor bgColor = style()->backgroundColor();
    if (document()->isHTMLDocument() && !style()->hasBackground()) {
        // Locate the <body> element using the DOM.  This is easier than trying
        // to crawl around a render tree with potential :before/:after content and
        // anonymous blocks created by inline <body> tags etc.  We can locate the <body>
        // render object very easily via the DOM.
        HTMLElementImpl* body = document()->body();
        RenderObject* bodyObject = (body && body->id() == ID_BODY) ? body->renderer() : 0;

        if (bodyObject) {
            bgLayer = bodyObject->style()->backgroundLayers();
            bgColor = bodyObject->style()->backgroundColor();
        }
    }

    if( !bgColor.isValid() && canvas()->view())
        bgColor = canvas()->view()->palette().active().color(QColorGroup::Base);

    int w = width();
    int h = height();

    //    kdDebug(0) << "width = " << w <<endl;

    int rw, rh;
    if (canvas()->view()) {
        rw = canvas()->view()->contentsWidth();
        rh = canvas()->view()->contentsHeight();
    } else {
        rw = canvas()->docWidth();
        rh = canvas()->docHeight();
    }

    //    kdDebug(0) << "rw = " << rw <<endl;

    int bx = _tx - marginLeft();
    int by = _ty - marginTop();
    int bw = QMAX(w + marginLeft() + marginRight() + borderLeft() + borderRight(), rw);
    int bh = QMAX(h + marginTop() + marginBottom() + borderTop() + borderBottom(), rh);

    // CSS2 14.2:
    // " The background of the box generated by the root element covers the entire canvas."
    // hence, paint the background even in the margin areas (unlike for every other element!)
    // I just love these little inconsistencies .. :-( (Dirk)
    int my = kMax(by, paintInfo.r.y());

    paintBackgrounds(paintInfo.p, bgColor, bgLayer, my, paintInfo.r.height(), bx, by, bw, bh);

    if(style()->hasBorder())
        paintBorder( paintInfo.p, _tx, _ty, w, h, style() );
}

void RenderBox::paintBoxDecorations(PaintInfo& paintInfo, int _tx, int _ty)
{
    //kdDebug( 6040 ) << renderName() << "::paintDecorations()" << endl;

    if(isRoot())
        return paintRootBoxDecorations(paintInfo, _tx, _ty);

    int w = width();
    int h = height() + borderTopExtra() + borderBottomExtra();
    _ty -= borderTopExtra();

    int my = kMax(_ty,paintInfo.r.y());
    int end = kMin( paintInfo.r.y() + paintInfo.r.height(), _ty + h );
    int mh = end - my;

   // The <body> only paints its background if the root element has defined a background
   // independent of the body.  Go through the DOM to get to the root element's render object,
   // since the root could be inline and wrapped in an anonymous block.

   if (!isBody() || !document()->isHTMLDocument() || document()->documentElement()->renderer()->style()->hasBackground())
        paintBackgrounds(paintInfo.p, style()->backgroundColor(), style()->backgroundLayers(), my, mh, _tx, _ty, w, h);

   if(style()->hasBorder()) {
        paintBorder(paintInfo.p, _tx, _ty, w, h, style());
    }
}

void RenderBox::paintBackgrounds(QPainter *p, const QColor& c, const BackgroundLayer* bgLayer, int clipy, int cliph, int _tx, int _ty, int w, int height)
 {
    if (!bgLayer) return;
    paintBackgrounds(p, c, bgLayer->next(), clipy, cliph, _tx, _ty, w, height);
    paintBackground(p, c, bgLayer, clipy, cliph, _tx, _ty, w, height);
}

void RenderBox::paintBackground(QPainter *p, const QColor& c, const BackgroundLayer* bgLayer, int clipy, int cliph, int _tx, int _ty, int w, int height)
{
    paintBackgroundExtended(p, c, bgLayer, clipy, cliph, _tx, _ty, w, height,
                            borderLeft(), borderRight());
}

void RenderBox::paintBackgroundExtended(QPainter *p, const QColor &c, const BackgroundLayer* bgLayer, int clipy, int cliph,
                                        int _tx, int _ty, int w, int h,
                                        int bleft, int bright)
{
    if ( cliph < 0 )
	return;

    CachedImage* bg = bgLayer->backgroundImage();
    bool shouldPaintBackgroundImage = bg && bg->pixmap_size() == bg->valid_rect().size() && !bg->isTransparent() && !bg->isErrorImage();
    QColor bgColor = c;

    // Paint the color first underneath all images.
    if (!bgLayer->next() && bgColor.isValid() && qAlpha(bgColor.rgb()) > 0)
        p->fillRect(_tx, clipy, w, cliph, bgColor);

    // no progressive loading of the background image
    if (shouldPaintBackgroundImage) {
        int sx = 0;
        int sy = 0;
        int cw,ch;
        int cx,cy;
        int vpab = bleft + bright;
        int hpab = borderTop() + borderBottom();