modules/gui/qt/components/info_widgets.cpp

   1 /*****************************************************************************
   2  * info_widgets.cpp : Widgets for info panels
   3  ****************************************************************************
   4  * Copyright (C) 2013 the VideoLAN team
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #include "qt.hpp"
  22 #include "info_widgets.hpp"
  23
  24 #include <QGridLayout>
  25 #include <QLabel>
  26 #include <QGraphicsView>
  27 #include <QGraphicsScene>
  28 #include <QPolygonF>
  29 #include <QGraphicsPolygonItem>
  30 #include <QGraphicsLineItem>
  31 #include <QVectorIterator>
  32
  33 #define STATS_LENGTH 60
  34 #define ADD_LABEL(row, color, text) \
  35 label = new QLabel( QString( "<font color=\"%1\">%2</font>" ) \
  36                     .arg( color.name() ) \
  37                     .arg( text ) \
  38                     ); \
  39 layout->addWidget( label, row, 0, 1, 1, 0 );
  40
  41 VLCStatsView::VLCStatsView( QWidget *parent ) : QGraphicsView( parent )
  42 {
  43     QColor history(0, 0, 0, 255),
  44         total(237, 109, 0, 160),
  45         content(109, 237, 0, 160);
  46
  47     scale( 1.0, -1.0 ); /* invert our Y axis */
  48     setOptimizationFlags( QGraphicsView::DontAdjustForAntialiasing );
  49     setAlignment( Qt::AlignLeft );
  50     setVerticalScrollBarPolicy( Qt::ScrollBarAlwaysOff );
  51     setHorizontalScrollBarPolicy( Qt::ScrollBarAlwaysOff );
  52     viewScene = new QGraphicsScene( this );
  53     historyShape = viewScene->addPolygon( QPolygonF(), QPen(Qt::NoPen),
  54                                              QBrush(history) );
  55     totalbitrateShape = viewScene->addPolygon( QPolygonF(), QPen(Qt::NoPen),
  56                                            QBrush(total) );
  57     setScene( viewScene );
  58     reset();
  59
  60     QPen linepen( Qt::DotLine );
  61     linepen.setCosmetic( true );
  62     linepen.setBrush( QBrush( QColor( 33, 33, 33 ) ) );
  63     for ( int i=0; i<3; i++ )
  64         rulers[i] = viewScene->addLine( QLineF(), linepen );
  65 }
  66 #undef ADD_LABEL
  67
  68 void VLCStatsView::reset()
  69 {
  70     historymergepointer = 0;
  71     blocksize = 4;
  72     valuesaccumulator = 0;
  73     valuesaccumulatorcount = 0;
  74     historyShape->setPolygon( QPolygonF() );
  75     totalbitrateShape->setPolygon( QPolygonF() );
  76 }
  77
  78 void VLCStatsView::addValue( float value )
  79 {
  80     value /= 1000;
  81
  82     QPolygonF shape = totalbitrateShape->polygon();
  83     if ( shape.count() > ( STATS_LENGTH + 2 ) ) /* keep only STATS_LENGTH samples */
  84     {
  85         shape.remove( 1 );
  86         for(int i=1; i<( STATS_LENGTH + 2 ); i++)
  87             ( (QPointF &) shape.at(i) ).setX( i - 1 ); /*move back values*/
  88     }
  89
  90     int count = shape.count();
  91     if ( count == 0 )
  92     {
  93         shape << QPointF( 0, 0 ); /* begin and close shape */
  94         shape << QPointF( count, 0 );
  95     }
  96
  97     shape.insert( shape.end() - 1, QPointF( count, value ) );
  98     ( (QPointF &) shape.last() ).setX( count );
  99     totalbitrateShape->setPolygon( shape );
 100
 101     addHistoryValue( value );
 102
 103     QRectF maxsizes = scene()->itemsBoundingRect();
 104     maxsizes.setRight( STATS_LENGTH );
 105     fitInView( maxsizes ); /* fix viewport */
 106     drawRulers( maxsizes );
 107 }
 108
 109 void VLCStatsView::drawRulers( const QRectF &maxsizes )
 110 {
 111     float height = maxsizes.height() * 1000;
 112     int texp = 0;
 113     while( height > 1.0 ) { height /= 10; texp++; }
 114     height = 1.0;
 115     while( texp-- ) height *= 10;
 116     for ( int i=0; i<3; i++ )
 117     {
 118         float y = ( height / 5 ) * ( i + 1 ) / 1000;
 119         rulers[i]->setLine( QLineF( 0, y, STATS_LENGTH, y ) );
 120     }
 121 }
 122
 123 void VLCStatsView::addHistoryValue( float value )
 124 {
 125     /* We keep a full history by creating virtual blocks for inserts, growing
 126        by power of 2 when no more space is available. At this time, we also
 127        free space by agregating the oldest values 2 by 2.
 128        Each shown value finally being a mean of blocksize samples.
 129     */
 130     bool doinsert = false;
 131     int next_blocksize = blocksize;
 132     QPolygonF shape = historyShape->polygon();
 133     int count = shape.count();
 134     if ( count == 0 )
 135     {
 136         shape << QPointF( 0, 0 ); /* begin and close shape */
 137         shape << QPointF( count, 0 );
 138     }
 139
 140     valuesaccumulator += ( value / blocksize );
 141     valuesaccumulatorcount++;
 142
 143     if ( valuesaccumulatorcount == blocksize )
 144     {
 145         valuesaccumulator = 0;
 146         valuesaccumulatorcount = 0;
 147         doinsert = true;
 148     }
 149
 150     if ( doinsert )
 151     {
 152         if ( count > ( STATS_LENGTH + 2 ) )
 153         {
 154             float y = 0;
 155             y += ((QPointF &) shape.at( historymergepointer + 1 )).y();
 156             y += ((QPointF &) shape.at( historymergepointer + 2 )).y();
 157             y /= 2;
 158
 159             /* merge */
 160             shape.remove( historymergepointer + 2 );
 161             ( (QPointF &) shape.at( historymergepointer + 1 ) ).setY( y );
 162             for(int i=historymergepointer +1; i<( STATS_LENGTH + 2 ); i++)
 163                 ( (QPointF &) shape.at(i) ).setX( i - 1 ); /*move back values*/
 164             historymergepointer++;
 165             if ( historymergepointer > ( STATS_LENGTH - 1 ) )
 166             {
 167                 historymergepointer = 0;
 168                 next_blocksize = ( blocksize << 1 );
 169             }
 170         }
 171
 172         shape.insert( shape.end() - 1, QPointF( count, value ) );
 173         ( (QPointF &) shape.last() ).setX( count );
 174     }
 175     else
 176         ( (QPointF &) shape.last() ).setX( count - 1 );
 177
 178     historyShape->setPolygon( shape );
 179
 180     blocksize = next_blocksize;
 181 }