src/qanEdgeItem.cpp

   1 /*
   2 Qanava - Graph drawing library for QT
   3 Copyright (C) 2006 Benoit AUTHEMAN
   4
   5 This library is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU Lesser General Public
   7 License as published by the Free Software Foundation; either
   8 version 2.1 of the License, or (at your option) any later version.
   9
  10 This library is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public
  16 License along with this library; if not, write to the Free Software
  17 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  18 */
  19
  20 //-----------------------------------------------------------------------------
  21 // This file is a part of the Qanava software.
  22 //
  23 // \file        qanEdgeItem.cpp
  24 // \author      Benoit Autheman (benoit@libqanava.org)
  25 // \date        2007 February 08
  26 //-----------------------------------------------------------------------------
  27
  28
  29 // Qanava headers
  30 #include "./qanNodeItem.h"
  31 #include "./qanEdgeItem.h"
  32
  33
  34 // QT headers
  35 #include <QGraphicsScene>
  36 #include <QPainter>
  37
  38
  39 namespace qan { // ::qan
  40
  41
  42 /* Arrow Constructor/Destructor *///-------------------------------------------
  43 EdgeItem::EdgeItem( Style::Manager& styleManager, Style* style, QGraphicsItem* parent, QGraphicsScene* scene,
  44                                         Edge& edge, NodeItem* src, NodeItem* dst ) :
  45         GraphItem( styleManager, style ),
  46         QGraphicsItem( parent, scene ),
  47         _edge( edge ),
  48         _src( src ),
  49         _dst( dst ),
  50         _hasArrow( true ),
  51         _arrowSize( 4 ),
  52         _lineType( Qt::SolidLine ),
  53         _lineWeight( 1 )
  54 {
  55         setZValue( 1. );
  56
  57         if ( src != 0 && dst != 0 )
  58         {
  59                 src->addEdge( this );
  60                 dst->addEdge( this );
  61                 updateItem( );
  62         }
  63
  64         setVisible( true );
  65 }
  66
  67 EdgeItem::~EdgeItem( )
  68 {
  69         // FIXME: segfault with node dtor
  70         /*if ( _src != 0 )
  71                 _src->removeEdge( this );
  72         if ( _dst != 0 )
  73                 _dst->removeEdge( this );*/
  74 }
  75
  76 QRectF  EdgeItem::boundingRect( ) const
  77 {
  78         if ( _src == 0 || _dst == 0 )
  79                 return QRectF( );
  80
  81         QPointF src = _src->mapToScene( _src->boundingRect( ).center( ) );
  82         QPointF dst = _dst->mapToScene( _dst->boundingRect( ).center( ) );
  83
  84         QPointF topLeft( qMin( src.x( ), dst.x( ) ),            // tl=(minx, miny)
  85                                          qMin( src.y( ), dst.y( ) ) );
  86         QPointF bottomRight( qMax( src.x( ), dst.x( ) ),    // br=(maxx, maxy)
  87                                                  qMax( src.y( ), dst.y( ) ) );
  88
  89         QRectF br( 0., 0., qAbs( bottomRight.x( ) - topLeft.x( ) ), qAbs( bottomRight.y( ) - topLeft.y( ) ) );
  90
  91         // Take the text label into account
  92         br = br.unite( _labelRect );
  93
  94         // Take the arrow into account
  95         br.adjust( -_arrowSize, -_arrowSize, _arrowSize, _arrowSize );
  96
  97         return br;
  98 }
  99
 100 void    EdgeItem::updateItem( )
 101 {
 102         if ( _src == 0 || _dst == 0 )
 103                 return;
 104
 105         QPointF srcF = _src->mapToScene( _src->boundingRect( ).center( ) );
 106         QPointF dstF = _dst->mapToScene( _dst->boundingRect( ).center( ) );
 107         QPointF topLeft( qMin( srcF.x( ), dstF.x( ) ),          // tl=(minx, miny)
 108                                          qMin( srcF.y( ), dstF.y( ) ) );
 109
 110         setPos( topLeft );  // setPos should have been called update on the old garbage area ?
 111
 112         if ( getStyle( ) != 0 && getStyle( )->has( "linetype" ) )
 113         {
 114                 _lineType = Qt::SolidLine;
 115                 const QVariant& value = getStyle( )->get( "linetype" );
 116                 if ( value.isValid( ) )
 117                         _lineType = value.value< int >( );
 118         }
 119         if ( getStyle( ) != 0 && getStyle( )->has( "lineweight" ) )
 120         {
 121                 _lineWeight = 1;
 122                 const QVariant& value = getStyle( )->get( "lineweight" );
 123                 if ( value.isValid( ) )
 124                         _lineWeight = value.value< int >( );
 125         }
 126         if ( getStyle( ) != 0 && getStyle( )->has( "arrowsize" ) )
 127         {
 128                 _arrowSize = 4;
 129                 const QVariant& value = getStyle( )->get( "arrowsize" );
 130                 if ( value.isValid( ) )
 131                         _arrowSize = value.value< int >( );
 132         }
 133
 134         QGraphicsItem::update( );
 135 }
 136
 137 void    EdgeItem::paint( QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget )
 138 {
 139         if ( _src == 0 || _dst == 0 )
 140                 return;
 141
 142         QPointF srcF = _src->mapToScene( _src->boundingRect( ).center( ) );
 143         QPointF dstF = _dst->mapToScene( _dst->boundingRect( ).center( ) );
 144         QLineF line( mapFromScene( srcF ), mapFromScene( dstF ) );
 145
 146         QPen arrowPen( Qt::black, _lineWeight, ( Qt::PenStyle )_lineType, Qt::RoundCap, Qt::RoundJoin );
 147
 148         if ( _edge.getLabel( ).length( ) > 0 )
 149         {
 150                 QPointF middleF = QPointF( 15., 5. ) + srcF + ( dstF - srcF ) / 2;
 151                 middleF = mapFromScene( middleF );
 152                 painter->setPen( QPen( Qt::black, 1, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin ) );
 153                 _labelRect = painter->boundingRect( QRectF( ), Qt::AlignLeft | Qt::AlignVCenter, _edge.getLabel( ) );
 154                 _labelRect.translate( middleF ); // Keep the label rect to compute the edge bbox
 155                 painter->drawText( middleF, _edge.getLabel( ) );
 156         }
 157
 158         if ( _hasArrow )
 159         {
 160                 const double Pi = 3.141592653;
 161                 double TwoPi = 2.0 * Pi;
 162                 double angle = ::acos( line.dx( ) / line.length( ) );
 163                 if ( line.dy( ) >= 0 )
 164                         angle = TwoPi - angle;
 165
 166                 // Get the intersection between arrow and dst node
 167                 QRectF br = mapFromItem( _dst, _dst->boundingRect( ) ).boundingRect( );
 168
 169                 // Test intersection with all borders
 170                 QLineF top( br.topLeft( ), br.topRight( ) );
 171                 QLineF right( br.topRight( ), br.bottomRight( ) );
 172                 QLineF bottom( br.bottomLeft( ), br.bottomRight( ) );
 173                 QLineF left( br.topLeft( ), br.bottomLeft( ) );
 174
 175                 QPointF i;
 176                 if ( line.intersect( top, &i ) == QLineF::BoundedIntersection ||
 177                         line.intersect( right, &i ) == QLineF::BoundedIntersection ||
 178                         line.intersect( bottom, &i ) == QLineF::BoundedIntersection ||
 179                         line.intersect( left, &i ) == QLineF::BoundedIntersection )
 180                 {
 181                         QLineF shortLine( mapFromScene( srcF ), i );
 182                         painter->setPen( arrowPen );
 183                         painter->drawLine( shortLine );
 184
 185                         painter->setRenderHint( QPainter::Antialiasing );
 186                         painter->setPen( QPen( Qt::black, 1, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin ) );
 187                         painter->setBrush( QBrush( QColor( 0, 0, 0 ) ) );
 188
 189                         double angle = ::acos( line.dx( ) / line.length( ) );
 190                         if ( line.dy( ) <= 0 )
 191                                 angle = TwoPi - angle;
 192                         painter->save( );
 193                         painter->translate( i );
 194                         painter->rotate( angle * 180. / Pi );
 195
 196                         double arrowSize = _arrowSize;
 197                         double arrowLength = _arrowSize * 2.;
 198                         i = QPointF( -arrowLength - 1., 0. );
 199                         QPolygonF poly;
 200                         poly    << QPointF( i.x( ), i.y( ) - arrowSize )
 201                                         << QPointF( i.x( ) + arrowLength, i.y( ) )
 202                                         << QPointF( i.x( ), i.y( ) + arrowSize ) << QPointF( i.x( ), i.y( ) - arrowSize );
 203                         painter->drawPolygon( poly );
 204                         painter->restore( );
 205                 }
 206         }
 207         else
 208         {
 209                 painter->setPen( arrowPen );
 210                 painter->drawLine( line );
 211         }
 212 }
 213
 214 void    EdgeItem::disconnectEdge( )
 215 {
 216         _src = 0;
 217         _dst = 0;
 218 }
 219
 220 void    EdgeItem::nodeDestroyed( )
 221 {
 222         disconnectEdge( );
 223 }
 224 //-----------------------------------------------------------------------------
 225
 226 }       // ::qan
 227