src/contextview/graphicsitemscaler.cpp

   1 /***************************************************************************
   2  *   Copyright (c) 2007  Nikolaj Hald Nielsen <nhnFreespirit@gmail.com>    *
   3  *                 2007  Jeff Mitchell <kde-dev@emailgoeshere.com>         *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program 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         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin Street, Fifth Floor, Boston, MA  02111-1307, USA.          *
  19  ***************************************************************************/
  20
  21 #include "contextbox.h"
  22 #include "graphicsitemscaler.h"
  23
  24 #include <math.h>
  25 #include "debug.h"
  26
  27 #include <QPen>
  28 #include <QTimer>
  29
  30 using namespace Context;
  31
  32 GraphicsItemScaler::GraphicsItemScaler( ContextBox *item )
  33     : QObject()
  34     , m_currWidth( item->boundingRect().width() )
  35     , m_currHeight( item->boundingRect().height() )
  36     , m_originalWidth( (int) item->boundingRect().width() )
  37     , m_originalHeight( (int) item->boundingRect().height() )
  38     , m_tgtWidth( 0 )
  39     , m_tgtHeight( 0 )
  40     , m_negativeWidth( false )
  41     , m_negativeHeight( false )
  42     , m_fps( 0 )
  43     , m_duration( 5000 )
  44     , m_delay( 0 )
  45 {
  46     DEBUG_BLOCK
  47     m_contentItem = item;
  48
  49     m_timeLine = new QTimeLine( m_duration, this );
  50     connect( m_timeLine, SIGNAL( frameChanged( int ) ), this, SLOT( scaleSlot( int ) ) );
  51     connect( m_timeLine, SIGNAL( finished() ), this, SLOT( scaleFinished() ) );
  52 }
  53
  54 GraphicsItemScaler::~GraphicsItemScaler()
  55 {
  56     m_timeLine->stop();
  57     scaleSlot( m_animationSteps );
  58 }
  59
  60 void GraphicsItemScaler::setTargetSize(int width, int height)
  61 {
  62     m_tgtWidth = width;
  63     m_tgtHeight = height;
  64 }
  65
  66 void GraphicsItemScaler::setDuration(int ms)
  67 {
  68     m_duration = ms;
  69 }
  70
  71 void GraphicsItemScaler::setFPS(int fps)
  72 {
  73     m_fps = fps;
  74 }
  75
  76 void GraphicsItemScaler::scaleSlot(int step)
  77 {
  78     debug() << "step # " << step << " of " << m_animationSteps << endl;
  79     if( step == 0 || ( m_currWidth == m_tgtWidth && m_currHeight == m_tgtHeight ) )
  80         return;
  81     qreal percent = ( qreal ) step / m_animationSteps;
  82
  83     qreal desiredWidth, desiredHeight;
  84     if( m_negativeWidth )
  85         desiredWidth = m_originalWidth + ( percent * ( m_tgtWidth - m_originalWidth ) );
  86     else
  87         desiredWidth = percent * m_tgtWidth;
  88
  89     if( m_negativeHeight )
  90         desiredHeight = m_originalHeight + ( percent * ( m_tgtHeight - m_originalHeight ) );
  91     else
  92         desiredHeight = percent * m_tgtHeight;
  93
  94     qreal scalefactorWidth = desiredWidth / m_currWidth;
  95     qreal scalefactorHeight = desiredHeight / m_currHeight;
  96
  97     m_contentItem->scale( scalefactorWidth, scalefactorHeight );
  98     m_currWidth = desiredWidth;
  99     m_currHeight = desiredHeight;
 100     m_contentItem->update();
 101 }
 102
 103 void GraphicsItemScaler::scaleFinished()
 104 {
 105     DEBUG_BLOCK
 106     scaleSlot( m_animationSteps );
 107     emit( animationComplete() );
 108 }
 109
 110 void GraphicsItemScaler::startScaling()
 111 {
 112     QTimer::singleShot( m_delay, this, SLOT(begin()) );
 113 }
 114
 115 void GraphicsItemScaler::begin()
 116 {
 117     DEBUG_BLOCK
 118     if( m_timeLine->state() != QTimeLine::NotRunning )
 119         m_timeLine->stop();
 120
 121     int fps = ( m_fps ? m_fps : 25 );
 122
 123     //total number of animation steps;
 124     m_animationSteps = (int) round( ( fps * ( ( qreal ) m_duration / 1000.0 ) ) );
 125
 126     if( m_animationSteps == 0 )
 127         m_animationSteps = 1;
 128
 129     m_originalWidth = (int) m_currWidth;
 130     m_originalHeight = (int) m_currHeight;
 131
 132     if( m_tgtWidth - m_currWidth < 0 )
 133         m_negativeWidth = true;
 134     if( m_tgtHeight - m_currHeight < 0 )
 135         m_negativeHeight = true;
 136
 137     debug() << "Start scaling, animationSteps = " << m_animationSteps << " over " << m_duration << " mseconds" << endl;
 138
 139     m_timeLine->setDuration( m_duration );
 140     m_timeLine->setFrameRange( 0, m_animationSteps );
 141     m_timeLine->start();
 142 }
 143
 144 #include "graphicsitemscaler.moc"