QtCollider/widgets/QcRangeSlider.cpp

   1 /************************************************************************
   2 *
   3 * Copyright 2010 Jakob Leben (jakob.leben@gmail.com)
   4 *
   5 * This file is part of SuperCollider Qt GUI.
   6 *
   7 * This program is free software: you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License as published by
   9 * the Free Software Foundation, either version 3 of the License, or
  10 * (at your option) any later version.
  11 *
  12 * This program is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 *
  20 ************************************************************************/
  21
  22 #include "QcRangeSlider.h"
  23 #include "../QcWidgetFactory.h"
  24
  25 #include <QKeyEvent>
  26 #include <QMouseEvent>
  27 #include <QApplication>
  28 #include <QPainter>
  29
  30 static QcWidgetFactory<QcRangeSlider> factory;
  31
  32 QcRangeSlider::QcRangeSlider() :
  33   _lo( 0.f ),
  34   _hi( 1.f ),
  35   _step( 0.01f ),
  36   mouseMode( None )
  37 {
  38   setFocusPolicy( Qt::StrongFocus );
  39   setOrientation( Qt::Vertical );
  40 }
  41
  42 void QcRangeSlider::setOrientation( Qt::Orientation o )
  43 {
  44   _ort = o;
  45
  46   if( _ort == Qt::Horizontal ) {
  47     setSizePolicy( QSizePolicy::Expanding, QSizePolicy::Preferred );
  48   }
  49   else {
  50     setSizePolicy( QSizePolicy::Preferred, QSizePolicy::Expanding );
  51   }
  52
  53   updateGeometry();
  54   update();
  55 }
  56
  57 void QcRangeSlider::setLoValue( float val )
  58 {
  59   val = qMax( 0.f, qMin( 1.f, val ) );
  60   if( val <= _hi ) {
  61     _lo = val;
  62   }
  63   else {
  64     _lo = _hi;
  65     _hi = val;
  66   }
  67   update();
  68 }
  69
  70 void QcRangeSlider::setHiValue( float val )
  71 {
  72   val = qMax( 0.f, qMin( 1.f, val ) );
  73   if( val >= _lo ) {
  74     _hi = val;
  75   }
  76   else {
  77     _hi = _lo;
  78     _lo = val;
  79   }
  80   update();
  81 }
  82
  83 QSize QcRangeSlider::sizeHint() const
  84 {
  85   return ( _ort == Qt::Horizontal ? QSize( 100, 20 ) : QSize( 20, 100 ) );
  86 }
  87
  88 QSize QcRangeSlider::minimumSizeHint() const
  89 {
  90   return ( _ort == Qt::Horizontal ? QSize( 30, 10 ) : QSize( 10, 30 ) );
  91 }
  92
  93 void QcRangeSlider::increment( double factor )
  94 {
  95   moveBy( factor * _step );
  96 }
  97
  98 void QcRangeSlider::decrement( double factor )
  99 {
 100   moveBy( -factor * _step );
 101 }
 102
 103 void QcRangeSlider::increment()
 104 {
 105   float step = _step;
 106   modifyStep( &step );
 107   moveBy( step );
 108 }
 109
 110 void QcRangeSlider::decrement()
 111 {
 112   float step = _step;
 113   modifyStep( &step );
 114   moveBy( -step );
 115 }
 116
 117 QRect QcRangeSlider::thumbRect()
 118 {
 119   QRect r;
 120
 121   if( _ort == Qt::Horizontal ) {
 122     r.setX( _lo * width() );
 123     r.setRight( _hi * width() );
 124     r.setHeight( height() );
 125   }
 126   else {
 127     r.setY( (1.f - _hi) * height() );
 128     r.setBottom( (1.f - _lo ) * height() );
 129     r.setWidth( width() );
 130   }
 131
 132   return r;
 133 }
 134
 135 float QcRangeSlider::valueFromPos( const QPoint& pos )
 136 {
 137   float val = _ort == Qt::Horizontal ?
 138               (float)pos.x() / width() :
 139               1.f - ((float)pos.y() / height());
 140   return val;
 141 }
 142
 143 void QcRangeSlider::moveBy( float dif )
 144 {
 145   if( _lo + dif < 0.f ) {
 146     _hi += 0.f - _lo;
 147     _lo = 0.f;
 148   }
 149   else if( _hi + dif > 1.f ) {
 150     _lo += 1.f - _hi;
 151     _hi = 1.f;
 152   }
 153   else {
 154     _lo += dif;
 155     _hi += dif;
 156   }
 157   update();
 158 }
 159
 160 void QcRangeSlider::mouseMoveEvent ( QMouseEvent * e )
 161 {
 162   if( mouseMode == Drag ) {
 163       QPoint pt = e->pos() + dragOffset;
 164       float dif;
 165       if( _ort == Qt::Horizontal )
 166         dif = ( (float)pt.x() / width() ) - _lo;
 167       else
 168         dif = 1.f - ( (float)pt.y() / height() ) - _hi;
 169
 170       if( dif == 0.f ) return;
 171
 172       moveBy( dif );
 173   }
 174   else {
 175     float val = valueFromPos( e->pos() );
 176     if( mouseMode == SetLo ) {
 177       if( val > _hi ) mouseMode = SetHi;
 178       setLoValue( val );
 179     }
 180     else if( mouseMode == SetHi ) {
 181       if( val < _lo ) mouseMode = SetLo;
 182       setHiValue( val );
 183     }
 184   }
 185
 186   Q_EMIT( action() );
 187 }
 188
 189 void QcRangeSlider::mousePressEvent ( QMouseEvent * e )
 190 {
 191   QRect r = thumbRect();
 192   if( e->modifiers() & Qt::ShiftModifier ) {
 193     float center = (_hi + _lo) * 0.5;
 194     float val = valueFromPos( e->pos() );
 195     if( val < center ) {
 196       mouseMode = SetLo;
 197       setLoValue( val );
 198     }
 199     else {
 200       mouseMode = SetHi;
 201       setHiValue( val );
 202     }
 203     Q_EMIT( action() );
 204   }
 205   else if( r.contains( e->pos() ) ){
 206     mouseMode = Drag;
 207     dragOffset = r.topLeft() - e->pos();
 208   }
 209   else {
 210     _lo = _hi = valueFromPos( e->pos() );
 211     update();
 212     mouseMode = SetHi;
 213     Q_EMIT( action() );
 214   }
 215 }
 216
 217 void QcRangeSlider::mouseReleaseEvent ( QMouseEvent * e )
 218 {
 219   Q_UNUSED(e);
 220   mouseMode = None;
 221 }
 222
 223 void QcRangeSlider::keyPressEvent ( QKeyEvent *e )
 224 {
 225   switch( e->key() ) {
 226     case Qt::Key_Up:
 227     case Qt::Key_Right:
 228       increment(); break;
 229     case Qt::Key_Down:
 230     case Qt::Key_Left:
 231       decrement(); break;
 232     case Qt::Key_A:
 233       _lo = 0.f; _hi = 1.f; update(); break;
 234     case Qt::Key_N:
 235       _lo = 0.f; _hi = 0.f; update(); break;
 236     case Qt::Key_X:
 237       _lo = 1.f; _hi = 1.f; update(); break;
 238     case Qt::Key_C:
 239       _lo = 0.5; _hi = 0.5; update(); break;
 240     default:
 241       return QWidget::keyPressEvent( e );
 242   }
 243   Q_EMIT( action() );
 244 }
 245
 246 void QcRangeSlider::paintEvent ( QPaintEvent *e )
 247 {
 248   Q_UNUSED(e);
 249   QPainter p;
 250   p.begin(this);
 251
 252   QPalette plt = palette();
 253
 254   p.setBrush( plt.color( QPalette::Base ) );
 255   p.setPen( plt.color( QPalette::Mid ) );
 256   p.drawRect( rect().adjusted(0,0,-1,-1) );
 257
 258   p.fillRect( thumbRect(), plt.color( QPalette::Text ) );
 259   p.end();
 260 }