render_flow.cpp

monqueror一个很具有参考价值的源玛

/**
 * This file is part of the html renderer for KDE.
 *
 * Copyright (C) 1999 Lars Knoll ([e-mail])
 *           (C) 1999 Antti Koivisto ([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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * $Id: render_flow.cpp,v 1.2 2002/01/28 04:31:02 leon Exp $
 */
// -------------------------------------------------------------------------
//#define DEBUG
//#define DEBUG_LAYOUT
//#define BOX_DEBUG

#include <assert.h>

#include "render_interface.h"
#include "mgcolor.h"
#include "mgpen.h"
#include "mgbrush.h"
#include "mgsize.h"
#include "mgrect.h"
#include "mgfontmetrics.h"
#include "mgpainter.h"
#include "mghtml_part.h"
#include "dom_string.h"

#include "render_flow.h"
#include "render_text.h"
#include "render_style.h"
#include "render_root.h"
#include "render_replaced.h"

#include "htmlhashes.h"

#include "kdebug.h"

using namespace DOM;
using namespace khtml;

#define DEBUG_BY_XHTANG 1

static inline int collapseMargins(int a, int b)
{
    if(a >= 0 && b >= 0) return (a > b ? a : b );
    if(a > 0 && b < 0) return a + b;
    if(a < 0 && b > 0) return b + a;
    return ( a > b ? b : a);
}

void RenderFlow::mysetLayouted(bool f)
{
    RenderObject *child = firstChild();
	while(child){
//		child->mysetLayouted(false);
		child->setLayouted(false);
		child = child->nextSibling();
	}
}

RenderFlow::RenderFlow()
    : RenderBox()
{
    m_inline = true;
    m_childrenInline = true;
    m_haveAnonymous = false;

    specialObjects = 0;
}

void RenderFlow::setStyle(RenderStyle *style)
{

//    kdDebug( 6040 ) << (void*)this<< " renderFlow::setstyle()" << endl;

    RenderBox::setStyle(style);

    if(m_positioned)
        m_style->setDisplay(BLOCK);

    if( m_floating || !style->display() == INLINE)
        m_inline = false;

    if (m_inline == true && m_childrenInline==false)
        m_inline = false;

    m_pre = false;
    if(m_style->whiteSpace() == PRE)
        m_pre = true;

    if (haveAnonymousBox())
    {
        RenderObject *child = firstChild();
        while(child != 0)
        {
            if(child->isAnonymousBox())
            {
                if (child->style())
                    delete child->style();
                RenderStyle* newStyle = new RenderStyle(style);
                newStyle->setDisplay(BLOCK);
                child->setPart(m_part);
                child->setStyle(newStyle);
                child->setIsAnonymousBox(true);
            }
            child = child->nextSibling();
        }

    }
}

RenderFlow::~RenderFlow()
{
    if (specialObjects)
        delete specialObjects;
    if(isAnonymousBox()) // usually the style object is deleted by the DOM tree, but
        // since anonymous boxes don't have a corresponding DOM element...
        delete m_style;
}

void RenderFlow::print(MGPainter *p, int _x, int _y, int _w, int _h,
                                 int _tx, int _ty)
{

#ifdef DEBUG_LAYOUT
    //kdDebug( 6040 ) << renderName() << "(RenderFlow) " << this << " ::print() x/y/w/h = ("  << xPos() << "/" << yPos() << "/" << width() << "/" << height()  << ")" << endl;
#endif

    if(!isInline())
    {
        _tx += m_x;
        _ty += m_y;
    }

    // check if we need to do anything at all...
    if(!isInline() && !containsPositioned() && !isRelPositioned() && !isPositioned() )
    {
        int h = m_height;
        if(specialObjects && floatBottom() > h) h = floatBottom();
        if((_ty > _y + _h) || (_ty + h < _y))
        {
            //kdDebug( 6040 ) << "cut!" << endl;
            return;
        }
    }

    printObject(p, _x, _y, _w, _h, _tx, _ty);
}

void RenderFlow::printObject(MGPainter *p, int _x, int _y,
                                       int _w, int _h, int _tx, int _ty)
{

#ifdef DEBUG_LAYOUT
    //kdDebug( 6040 ) << renderName() << "(RenderFlow) " << this << " ::printObject() w/h = (" << width() << "/" << height() << ")" << endl;
#endif
    // add offset for relative positioning
    if(isRelPositioned())
	{
        relativePositionOffset(_tx, _ty);
//		kdDebug(0) << "flow " << _tx << ", " << _ty << endl;
	}

    // 1. print background, borders etc
    if(m_printSpecial && !isInline() && m_visible)
        printBoxDecorations(p, _x, _y, _w, _h, _tx, _ty);

    // 2. print contents
    RenderObject *child = firstChild();
    while(child != 0)
    {
		if(!child->isFloating() && !child->isPositioned())
			{
			child->print(p, _x, _y, _w, _h, _tx, _ty);
		}

        child = child->nextSibling();
    }
	
    // 3. print floats and other non-flow objects
    if(specialObjects)
    {
        SpecialObject* r;
        QListIterator<SpecialObject> it(*specialObjects);
        for ( ; (r = it.current()); ++it ) {
            if (r->node->containingBlock()==this) {
                RenderObject *o = r->node;
                //kdDebug(0) << renderName() << "printing positioned at " << _tx + o->xPos() << "/" << _ty + o->yPos()<< endl;
                o->print(p, _x, _y, _w, _h, _tx , _ty);
            }
        }
    }
#ifdef BOX_DEBUG
    if(isAnonymousBox())
	outlineBox(p, _tx, _ty, "green");
    else
	outlineBox(p, _tx, _ty);
#endif

}

void RenderFlow::setPos( int xPos, int yPos )
{
    m_y = yPos;
    setXPos(xPos);
}

void RenderFlow::setXPos( int xPos )
{
    m_x = xPos;
}


void RenderFlow::layout()
{
    //kdDebug( 6040 ) << renderName() << " " << this << "::layout() start" << endl;
    //QTime t;
    //t.start();

    assert(!isInline());

    int oldWidth = m_width;

    calcWidth();

//    kdDebug( 6040 ) << specialObjects << "," << oldWidth << ","
//            << m_width << ","<< layouted() << "," << isAnonymousBox() << endl;

    if ( (!specialObjects || (isListItem() && specialObjects->count() == 1) ) && oldWidth == m_width && layouted() && !isAnonymousBox()
            && !containsPositioned() && !isPositioned()) return;


#ifdef DEBUG_LAYOUT
    //kdDebug( 6040 ) << renderName() << "(RenderFlow) " << this << " ::layout() width=" << m_width << ", layouted=" << layouted() << endl;
    //if(containingBlock() == static_cast<RenderObject *>(this))
        //kdDebug( 6040 ) << renderName() << ": containingBlock == this" << endl;
#endif

    if(m_width<=0) {
        if(m_y < 0) m_y = 0;
        setLayouted();
        return;
    }

    clearFloats();

    m_height = 0;
    m_clearStatus = CNONE;

//    kdDebug( 6040 ) << "childrenInline()=" << childrenInline() << endl;
    if(childrenInline())
        layoutInlineChildren();
    else
        layoutBlockChildren();

    calcHeight();
    
    if(hasOverhangingFloats())
    {
        if(isFloating() || isTableCell())
        {
            m_height = floatBottom();
            m_height += borderBottom() + paddingBottom();
        }
    }    
    else if (isTableCell() && m_last && m_last->hasOverhangingFloats()) 
    {
        m_height = m_last->yPos() + static_cast<RenderFlow*>(m_last)->floatBottom();
        m_height += borderBottom() + paddingBottom();       
    }
    
    layoutSpecialObjects();

    //kdDebug() << renderName() << " layout width=" << m_width << " height=" << m_height << endl; 
    
    setLayouted();
}

void RenderFlow::layoutSpecialObjects()
{
    if(specialObjects) {
	//kdDebug( 6040 ) << renderName() << " " << this << "::layoutSpecialObjects() start" << endl;

        SpecialObject* r;
        QListIterator<SpecialObject> it(*specialObjects);
        for ( ; (r = it.current()); ++it ) {
            //kdDebug(6040) << "have a positioned object" << endl;
            if (r->type == SpecialObject::Positioned)
                r->node->layout();
        }
        specialObjects->sort();
    }
}

void RenderFlow::layoutBlockChildren()
{
#ifdef DEBUG_LAYOUT
    //kdDebug( 6040 ) << renderName() << " layoutBlockChildren( )" << endl;
#endif

    bool _layouted = true;
    int xPos = 0;
    int toAdd = 0;

    m_height = 0;

    if(m_style->hasBorder())
    {
        xPos += borderLeft();
        m_height += borderTop();
        toAdd += borderBottom();
    }
    if(m_style->hasPadding())
    {
        xPos += paddingLeft();
        m_height += paddingTop();
        toAdd += paddingBottom();
    }

    if( m_style->direction() == RTL ) {
        xPos = marginLeft() + m_width - paddingRight() - borderRight();
    }

    RenderObject *child = firstChild();
    RenderFlow *prevFlow = 0;
    
    int prevMargin = 0;
    if(isTableCell() && child)
        prevMargin = -child->marginTop();

    //QTime t;
    //t.start();

    while( child != 0 )
    {
        //kdDebug( 6040 ) << "   " << child->renderName() << " loop " << child << ", " << child->isInline() << ", " << child->layouted() << endl;
        //kdDebug( 6040 ) << t.elapsed() << endl;
        // ### might be some layouts are done two times... FIX that.

        if (child->isPositioned())
        {
            child->layout();
            static_cast<RenderFlow*>(child->containingBlock())->insertPositioned(child);
	    //kdDebug() << "RenderFlow::layoutBlockChildren inserting positioned into " << child->containingBlock()->renderName() << endl; 
            child = child->nextSibling();
            continue;
        } else if ( child->isReplaced() )
            child->layout();

        if(checkClear(child)) prevMargin = 0; // ### should only be 0
        // if oldHeight+prevMargin < newHeight
        int margin = child->marginTop();
        //kdDebug(0) << "margin = " << margin << " prevMargin = " << prevMargin << endl;
        margin = collapseMargins(margin, prevMargin);

        m_height += margin;

        //kdDebug(0) << "margin = " << margin << " yPos = " << m_height << endl;

        if(prevFlow)
        {
            if (prevFlow->yPos()+prevFlow->floatBottom() > m_height)
                child->setLayouted(false);
            else
                prevFlow=0;
        }          
        
        child->setYPos(m_height);
        child->layout();                                                     

        int chPos = xPos + child->marginLeft();

        if( m_style->textAlign() == KONQ_CENTER && !child->style()->marginLeft().isVariable()) {
            //kdDebug() << "should align to center" << endl;
            chPos += ( width() - child->width() )/2;
        } else if(m_style->direction() == LTR) {
            // html blocks flow around floats
            if (style()->htmlHacks() && child->style()->flowAroundFloats() )
                chPos = leftOffset(m_height) + child->marginLeft();
        } else {
            chPos -= child->width() + child->marginLeft() + child->marginRight();
            if (style()->htmlHacks() && child->style()->flowAroundFloats() )
                chPos -= leftOffset(m_height);
        }
        child->setXPos(chPos);

        m_height += child->height();

        prevMargin = child->marginBottom();
        
        if (child->isFlow())
            prevFlow = static_cast<RenderFlow*>(child);
		
		//kdDebug() << "In function: RenderFlow::layoutBlockChildren" << endl;
		//kdDebug() << "child name is " << child->renderName() << endl;
                
        child = child->nextSibling();
    }

    if(!isTableCell())
	m_height += prevMargin;
    m_height += toAdd;

    setLayouted(_layouted);

    // kdDebug( 6040 ) << "layouted = " << layouted_ << endl;
}

bool RenderFlow::checkClear(RenderObject *child)
{
    //kdDebug( 6040 ) << "checkClear oldheight=" << m_height << endl;
    RenderObject *o = child->previousSibling();
    while(o && !o->isFlow())
        o = o->previousSibling();
    if(!o) o = this;

    RenderFlow *prev = static_cast<RenderFlow *>(o);

    switch(child->style()->clear())
    {
    case CNONE:
        return false;
    case CLEFT:
    {
        int bottom = prev->leftBottom() + prev->yPos();
        if(m_height < bottom)
            m_height = bottom; //###  + lastFloat()->marginBotton()?
        break;
    }
    case CRIGHT:
    {
        int bottom = prev->rightBottom() + prev->yPos();
        if(m_height < bottom)
            m_height = bottom; //###  + lastFloat()->marginBotton()?
        break;
    }
    case CBOTH:
    {
        int bottom = prev->floatBottom() + prev->yPos();
        if(m_height < bottom)
            m_height = bottom; //###  + lastFloat()->marginBotton()?
        break;
    }
    }
    //kdDebug( 6040 ) << "    newHeight = " << m_height << endl;
    return true;
}

void
RenderFlow::insertPositioned(RenderObject *o)
{
    //kdDebug() << renderName() << "::insertPositioned " << this<< isAnonymousBox() << " " << o << endl;
    if(!specialObjects) {
        specialObjects = new QSortedList<SpecialObject>;
        specialObjects->setAutoDelete(true);
    }

    // don't insert it twice!
    QListIterator<SpecialObject> it(*specialObjects);
    SpecialObject* f;
    while ( (f = it.current()) ) {
        if (f->node == o) return;
        ++it;
    }