AutomationEditor: add option for smooth lines and curves

Besides discrete automation it's now possible to setup interpolation
modes such as linear and cubic-hermite.

Signed-off-by: Tobias Doerffel <tobias.doerffel@gmail.com>

src/core/AutomationPattern.cpp

@@ -41,7 +41,9 @@
 AutomationPattern::AutomationPattern( AutomationTrack * _auto_track ) :
 	trackContentObject( _auto_track ),
 	m_autoTrack( _auto_track ),
-	m_objects()
+	m_objects(),
+	m_tension( "1.0" ),
+	m_progressionType( DiscreteProgression )
 {
 	changeLength( midiTime( 1, 0 ) );
 }
@@ -52,12 +54,15 @@ AutomationPattern::AutomationPattern( AutomationTrack * _auto_track ) :
 AutomationPattern::AutomationPattern( const AutomationPattern & _pat_to_copy ) :
 	trackContentObject( _pat_to_copy.m_autoTrack ),
 	m_autoTrack( _pat_to_copy.m_autoTrack ),
-	m_objects( _pat_to_copy.m_objects )
+	m_objects( _pat_to_copy.m_objects ),
+	m_tension( _pat_to_copy.m_tension ),
+	m_progressionType( _pat_to_copy.m_progressionType )
 {
 	for( timeMap::const_iterator it = _pat_to_copy.m_timeMap.begin();
 				it != _pat_to_copy.m_timeMap.end(); ++it )
 	{
 		m_timeMap[it.key()] = it.value();
+		m_tangents[it.key()] = _pat_to_copy.m_tangents[it.key()];
 	}
 }
 
@@ -115,6 +120,35 @@ void AutomationPattern::addObject( AutomatableModel * _obj, bool _search_dup )
 
 
 
+void AutomationPattern::setProgressionType(
+					ProgressionTypes _new_progression_type )
+{
+	if ( _new_progression_type == DiscreteProgression ||
+		_new_progression_type == LinearProgression ||
+		_new_progression_type == CubicHermiteProgression )
+	{
+		m_progressionType = _new_progression_type;
+		emit dataChanged();
+	}
+}
+
+
+
+
+void AutomationPattern::setTension( QString _new_tension )
+{
+	bool ok;
+	float nt = _new_tension.toFloat( & ok );
+
+	if( ok && nt > -0.01 && nt < 1.01 )
+	{
+		m_tension = _new_tension;
+	}
+}
+
+
+
+
 const AutomatableModel * AutomationPattern::firstObject() const
 {
 	AutomatableModel * m;
@@ -159,6 +193,12 @@ midiTime AutomationPattern::putValue( const midiTime & _time,
 		_time;
 
 	m_timeMap[newTime] = _value;
+	timeMap::const_iterator it = m_timeMap.find( newTime );
+	if( it != m_timeMap.begin() )
+	{
+		it--;
+	}
+	generateTangents(it, 3);
 
 	// we need to maximize our length in case we're part of a hidden
 	// automation track as the user can't resize this pattern
@@ -180,6 +220,13 @@ void AutomationPattern::removeValue( const midiTime & _time )
 	cleanObjects();
 
 	m_timeMap.remove( _time );
+	m_tangents.remove( _time );
+	timeMap::const_iterator it = m_timeMap.lowerBound( _time );
+	if( it != m_timeMap.begin() )
+	{
+		it--;
+	}
+	generateTangents(it, 3);
 
 	if( getTrack() &&
 		getTrack()->type() == track::HiddenAutomationTrack )
@@ -214,7 +261,68 @@ float AutomationPattern::valueAt( const midiTime & _time ) const
 		return 0;
 	}
 
-	return (v-1).value();
+	return valueAt( v-1, _time - (v-1).key() );
+}
+
+
+
+
+float AutomationPattern::valueAt( timeMap::const_iterator v, int offset ) const
+{
+	if( m_progressionType == DiscreteProgression || v == m_timeMap.end() )
+	{
+		return v.value();
+	}
+	else if( m_progressionType == LinearProgression )
+	{
+		float slope = ((v+1).value() - v.value()) /
+							((v+1).key() - v.key());
+		return v.value() + offset * slope;
+	}
+	else /* CubicHermiteProgression */
+	{
+		// Implements a Cubic Hermite spline as explained at:
+		// http://en.wikipedia.org/wiki/Cubic_Hermite_spline#Unit_interval_.280.2C_1.29
+		//
+		// Note that we are not interpolating a 2 dimensional point over
+		// time as the article describes.  We are interpolating a single
+		// value: y.  To make this work we map the values of x that this
+		// segment spans to values of t for t = 0.0 -> 1.0 and scale the
+		// tangents _m1 and _m2
+		int numValues = ((v+1).key() - v.key());
+		float t = (float) offset / (float) numValues;
+		float m1 = (m_tangents[v.key()]) * numValues
+							* m_tension.toFloat();
+		float m2 = (m_tangents[(v+1).key()]) * numValues
+							* m_tension.toFloat();
+
+		return ( 2*pow(t,3) - 3*pow(t,2) + 1 ) * v.value()
+				+ ( pow(t,3) - 2*pow(t,2) + t) * m1
+				+ ( -2*pow(t,3) + 3*pow(t,2) ) * (v+1).value()
+				+ ( pow(t,3) - pow(t,2) ) * m2;
+	}
+}
+
+
+
+
+float *AutomationPattern::valuesAfter( const midiTime & _time ) const
+{
+	timeMap::ConstIterator v = m_timeMap.lowerBound( _time );
+	if( v == m_timeMap.end() || (v+1) == m_timeMap.end() )
+	{
+		return NULL;
+	}
+
+	int numValues = (v+1).key() - v.key();
+	float *ret = new float[numValues];
+
+	for( int i = 0; i < numValues; i++ )
+	{
+		ret[i] = valueAt( v, i );
+	}
+
+	return ret;
 }
 
 
@@ -225,6 +333,8 @@ void AutomationPattern::saveSettings( QDomDocument & _doc, QDomElement & _this )
 	_this.setAttribute( "pos", startPosition() );
 	_this.setAttribute( "len", trackContentObject::length() );
 	_this.setAttribute( "name", name() );
+	_this.setAttribute( "prog", QString::number( progressionType() ) );
+	_this.setAttribute( "tens", getTension() );
 
 	for( timeMap::const_iterator it = m_timeMap.begin();
 						it != m_timeMap.end(); ++it )
@@ -256,6 +366,9 @@ void AutomationPattern::loadSettings( const QDomElement & _this )
 
 	movePosition( _this.attribute( "pos" ).toInt() );
 	setName( _this.attribute( "name" ) );
+	setProgressionType( static_cast<ProgressionTypes>( _this.attribute(
+							"prog" ).toInt() ) );
+	setTension( _this.attribute( "tens" ) );
 
 	for( QDomNode node = _this.firstChild(); !node.isNull();
 						node = node.nextSibling() )
@@ -282,6 +395,7 @@ void AutomationPattern::loadSettings( const QDomElement & _this )
 		len = length();
 	}
 	changeLength( len );
+	generateTangents();
 }
 
 
@@ -442,6 +556,7 @@ void AutomationPattern::resolveAllIDs()
 void AutomationPattern::clear()
 {
 	m_timeMap.clear();
+	m_tangents.clear();
 
 	emit dataChanged();
 
@@ -476,6 +591,7 @@ void AutomationPattern::objectDestroyed( jo_id_t _id )
 
 
 
+
 void AutomationPattern::cleanObjects()
 {
 	for( objectVector::iterator it = m_objects.begin(); it != m_objects.end(); )
@@ -492,5 +608,47 @@ void AutomationPattern::cleanObjects()
 }
 
 
-#include "moc_AutomationPattern.cxx"
 
+
+void AutomationPattern::generateTangents()
+{
+	generateTangents(m_timeMap.begin(), m_timeMap.size());
+}
+
+
+
+
+void AutomationPattern::generateTangents( timeMap::const_iterator it,
+							int numToGenerate )
+{
+	if( m_timeMap.size() < 2 )
+	{
+		m_tangents[it.key()] = 0;
+		return;
+	}
+
+	for( int i = 0; i < numToGenerate; i++ )
+	{
+		if( it == m_timeMap.begin() )
+		{
+			m_tangents[it.key()] =
+					( (it+1).value() - (it).value() ) /
+						( (it+1).key() - (it).key() );
+		}
+		else if( it+1 == m_timeMap.end() )
+		{
+			m_tangents[it.key()] = 0;
+			return;
+		}
+		else
+		{
+			m_tangents[it.key()] =
+					( (it+1).value() - (it-1).value() ) /
+						( (it+1).key() - (it-1).key() );
+		}
+		it++;
+	}
+}
+
+
+#include "moc_AutomationPattern.cxx"

src/gui/AutomationEditor.cpp

@@ -169,8 +169,6 @@ AutomationEditor::AutomationEditor() :
 		tr( "Click here if you want to stop playing of the "
 			"current pattern." ) );
 
-
-
 	removeSelection();
 
 	// init scrollbars
@@ -241,6 +239,70 @@ AutomationEditor::AutomationEditor() :
 			"mode. You can also press 'Shift+M' on your keyboard "
 			"to activate this mode." ) );
 
+	m_discreteButton = new toolButton( embed::getIconPixmap(
+						"progression_discrete" ),
+					tr( "Discrete progression" ),
+					this, SLOT( discreteButtonToggled() ),
+					m_toolBar );
+	m_discreteButton->setCheckable( true );
+	m_discreteButton->setChecked( true );
+
+	m_linearButton = new toolButton( embed::getIconPixmap(
+							"progression_linear" ),
+					tr( "Linear progression" ),
+					this, SLOT( linearButtonToggled() ),
+					m_toolBar );
+	m_linearButton->setCheckable( true );
+
+	m_cubicHermiteButton = new toolButton( embed::getIconPixmap(
+						"progression_cubic_hermite" ),
+					tr( "Cubic Hermite progression" ),
+					this, SLOT(
+						cubicHermiteButtonToggled() ),
+					m_toolBar );
+	m_cubicHermiteButton->setCheckable( true );
+
+	// setup tension-stuff
+	m_tensionComboBox = new comboBox( m_toolBar );
+	m_tensionComboBox->setFixedSize( 60, 22 );
+
+	for( int i = 0; i < 4; ++i )
+	{
+		m_tensionModel.addItem( "0." + QString::number( 25 * i ) );
+	}
+	m_tensionModel.addItem( "1.0" );
+	m_tensionModel.setValue( m_tensionModel.findText( "1.0" ) );
+
+	m_tensionDisabledModel.addItem( "-----" );
+	disableTensionComboBox();
+
+	connect( &m_tensionModel, SIGNAL( dataChanged() ),
+			this, SLOT( tensionChanged() ) );
+	
+	tool_button_group = new QButtonGroup( this );
+	tool_button_group->addButton( m_discreteButton );
+	tool_button_group->addButton( m_linearButton );
+	tool_button_group->addButton( m_cubicHermiteButton );
+	tool_button_group->setExclusive( true );
+
+	m_discreteButton->setWhatsThis(
+		tr( "Click here to choose discrete progressions for this "
+			"automation pattern.  The value of the connected "
+			"object will remain constant between control points "
+			"and be set immediately to the new value when each "
+			"control point is reached." ) );
+	m_linearButton->setWhatsThis(
+		tr( "Click here to choose linear progressions for this "
+			"automation pattern.  The value of the connected "
+			"object will change at a steady rate over time "
+			"between control points to reach the correct value at "
+			"each control point without a sudden change." ) );
+	m_cubicHermiteButton->setWhatsThis(
+		tr( "Click here to choose cubic hermite progressions for this "
+			"automation pattern.  The value of the connected "
+			"object will change in a smooth curve and ease in to "
+			"the peaks and valleys." ) );
+
 	m_cutButton = new toolButton( embed::getIconPixmap( "edit_cut" ),
 					tr( "Cut selected values (Ctrl+X)" ),
 					this, SLOT( cutSelectedValues() ),
@@ -335,6 +397,12 @@ AutomationEditor::AutomationEditor() :
 	tb_layout->addWidget( m_selectButton );
 	tb_layout->addWidget( m_moveButton );
 	tb_layout->addSpacing( 10 );
+	tb_layout->addWidget( m_discreteButton );
+	tb_layout->addWidget( m_linearButton );
+	tb_layout->addWidget( m_cubicHermiteButton );
+	tb_layout->addSpacing( 5 );
+	tb_layout->addWidget( m_tensionComboBox );
+	tb_layout->addSpacing( 10 );
 	tb_layout->addWidget( m_cutButton );
 	tb_layout->addWidget( m_copyButton );
 	tb_layout->addWidget( m_pasteButton );
@@ -385,6 +453,7 @@ AutomationEditor::~AutomationEditor()
 {
 	m_zoomingXModel.disconnect();
 	m_zoomingYModel.disconnect();
+	m_tensionModel.disconnect();
 }
 
 
@@ -455,6 +524,29 @@ void AutomationEditor::updateAfterPatternChange()
 		return;
 	}
 
+	if( m_pattern->progressionType() ==
+				AutomationPattern::DiscreteProgression && 
+				!m_discreteButton->isChecked() )
+	{
+		m_discreteButton->setChecked( true );
+	}
+
+	if( m_pattern->progressionType() ==
+				AutomationPattern::LinearProgression &&
+				!m_linearButton->isChecked() )
+	{
+		m_linearButton->setChecked( true );
+	}
+
+	if( m_pattern->progressionType() ==
+				AutomationPattern::CubicHermiteProgression &&
+				!m_cubicHermiteButton->isChecked() )
+	{
+		m_cubicHermiteButton->setChecked( true );
+	}
+
+	m_tensionModel.setValue( m_tensionModel.findText(
+						m_pattern->getTension() ) );
 	m_minLevel = m_pattern->firstObject()->minValue<float>();
 	m_maxLevel = m_pattern->firstObject()->maxValue<float>();
 	m_step = m_pattern->firstObject()->step<float>();
@@ -487,28 +579,6 @@ void AutomationEditor::update()
 
 
 
-inline void AutomationEditor::drawValueRect( QPainter & _p,
-						int _x, int _y,
-						int _width, int _height,
-						const bool _is_selected )
-{
-	QColor current_color( 0xFF, 0xB0, 0x00 );
-	if( _is_selected == TRUE )
-	{
-		current_color.setRgb( 0x00, 0x40, 0xC0 );
-	}
-	_p.fillRect( _x, _y, _width, _height, current_color );
-
-	_p.drawLine( _x - 1, _y, _x + 1, _y );
-	_p.drawLine( _x, _y - 1, _x, _y + 1 );
-//	_p.setPen( QColor( 0xFF, 0x9F, 0x00 ) );
-
-//	_p.setPen( QColor( 0xFF, 0xFF, 0x40 ) );
-}
-
-
-
-
 void AutomationEditor::removeSelection()
 {
 	m_selectStartTick = 0;
@@ -727,6 +797,19 @@ void AutomationEditor::drawLine( int _x0, float _y0, int _x1, float _y1 )
 
 
 
+void AutomationEditor::disableTensionComboBox()
+{
+	m_tensionComboBox->setEnabled( false );
+	m_tensionComboBox->setModel( &m_tensionDisabledModel );
+	m_tensionComboBox->setToolTip(
+			tr( "Choose Cubic Hermite progression to enable" ) );
+	m_tensionComboBox->setWhatsThis(
+		tr( "Choose Cubic Hermite progression to enable" ) );
+}
+
+
+
+
 void AutomationEditor::mousePressEvent( QMouseEvent * _me )
 {
 	QMutexLocker m( &m_patternMutex );
@@ -1446,103 +1529,74 @@ void AutomationEditor::paintEvent( QPaintEvent * _pe )
 
 	if( validPattern() )
 	{
+		Sint32 len_ticks = 4;
 		timeMap & time_map = m_pattern->getTimeMap();
 		timeMap::iterator it = time_map.begin();
 		p.setPen( QColor( 0xFF, 0xDF, 0x20 ) );
 
-		while( it != time_map.end() )
+		while( it+1 != time_map.end() )
 		{
-			Sint32 len_ticks = 4;
+			// skip this section if it occurs completely before the
+			// visible area
+			int next_x = xCoordOfTick( (it+1).key() );
+			if( next_x < 0 )
+			{
+				++it;
+				continue;
+			}
 
-			const float level = it.value();
-
-			Sint32 pos_ticks = it.key();
-
-			const int x = ( pos_ticks - m_currentPosition ) *
-						m_ppt / DefaultTicksPerTact;
-			if( x > width() - VALUES_WIDTH )
+			int x = xCoordOfTick( it.key() );
+			if( x > width() )
 			{
 				break;
 			}
 
-			int rect_width;
-			if( it+1 != time_map.end() )
+			bool is_selected = FALSE;
+			// if we're in move-mode, we may only draw
+			// values in selected area, that have originally
+			// been selected and not values that are now in
+			// selection because the user moved it...
+			if( m_editMode == MOVE )
 			{
-				timeMap::iterator it_prev = it+1;
-				Sint32 next_pos_ticks = it_prev.key();
-				int next_x = ( next_pos_ticks
-					- m_currentPosition ) * m_ppt /
-							DefaultTicksPerTact;
-				// skip this value if not in visible area at all
-/*				if( next_x > width() )
-				{
-					break;
-				}*/
-				rect_width = next_x - x;
-			}
-			else
-			{
-				rect_width = width() - x;
-			}
-
-			// is the value in visible area?
-			if( ( level >= m_bottomLevel && level <= m_topLevel )
-				|| ( level > m_topLevel && m_topLevel >= 0 )
-				|| ( level < m_bottomLevel
-						&& m_bottomLevel <= 0 ) )
-			{
-				bool is_selected = FALSE;
-				// if we're in move-mode, we may only draw
-				// values in selected area, that have originally
-				// been selected and not values that are now in
-				// selection because the user moved it...
-				if( m_editMode == MOVE )
-				{
-					if( m_selValuesForMove.contains(
-								it.key() ) )
-					{
-						is_selected = TRUE;
-					}
-				}
-				else if( level >= selLevel_start &&
-					level <= selLevel_end &&
-					pos_ticks >= sel_pos_start &&
-					pos_ticks + len_ticks <=
-								sel_pos_end )
+				if( m_selValuesForMove.contains( it.key() ) )
 				{
 					is_selected = TRUE;
 				}
-
-				// we've done and checked all, lets draw the
-				// value
-				int y_start;
-				int rect_height;
-				if( m_y_auto )
-				{
-					y_start = (int)( grid_bottom
-						- ( grid_bottom - TOP_MARGIN )
-						* ( level - m_minLevel )
-						/ ( m_maxLevel - m_minLevel ) );
-					int y_end = (int)( grid_bottom
-						+ ( grid_bottom - TOP_MARGIN )
-						* m_minLevel
-						/ ( m_maxLevel - m_minLevel ) );
-					rect_height = y_end - y_start;
-				}
-				else
-				{
-					y_start = (int)( grid_bottom - ( level
-							- m_bottomLevel )
-							* m_y_delta );
-					rect_height = (int)( level * m_y_delta );
-				}
-				drawValueRect( p, x + VALUES_WIDTH, y_start,
-							rect_width, rect_height,
-							is_selected );
 			}
-			else printf("not in range\n");
+			else if( it.value() >= selLevel_start &&
+				it.value() <= selLevel_end &&
+				it.key() >= sel_pos_start &&
+				it.key() + len_ticks <= sel_pos_end )
+			{
+				is_selected = TRUE;
+			}
+
+			float *values = m_pattern->valuesAfter( it.key() );
+			for( int i = 0; i < (it+1).key() - it.key(); i++ )
+			{
+				drawLevelTick( p, it.key() + i, values[i],
+								is_selected );
+			}
+			delete [] values;
+			
+			// Draw cross
+			int y = yCoordOfLevel( it.value() );
+			p.drawLine( x - 1, y, x + 1, y );
+			p.drawLine( x, y - 1, x, y + 1 );
+		//	_p.setPen( QColor( 0xFF, 0x9F, 0x00 ) );
+		//	_p.setPen( QColor( 0xFF, 0xFF, 0x40 ) );
+
 			++it;
 		}
+
+		for( int i = it.key(), x = xCoordOfTick( i ); x <= width();
+						i++, x = xCoordOfTick( i ) )
+		{
+			// TODO: Find out if the section after the last control
+			// point is able to be selected and if so set this
+			// boolean correctly
+			drawLevelTick( p, i, it.value(), false );
+		}
 	}
 	else
 	{
@@ -1611,6 +1665,79 @@ void AutomationEditor::paintEvent( QPaintEvent * _pe )
 
 
 
+int AutomationEditor::xCoordOfTick( int _tick )
+{
+	return VALUES_WIDTH + ( ( _tick - m_currentPosition )
+						* m_ppt / DefaultTicksPerTact );
+}
+
+
+
+
+int AutomationEditor::yCoordOfLevel( float _level )
+{
+	int grid_bottom = height() - SCROLLBAR_SIZE - 1;
+	if( m_y_auto )
+	{
+		return (int)( grid_bottom - ( grid_bottom - TOP_MARGIN )
+						* ( _level - m_minLevel )
+						/ ( m_maxLevel - m_minLevel ) );
+	}
+	else
+	{
+		return (int)( grid_bottom - ( _level - m_bottomLevel )
+								* m_y_delta );
+	}
+}
+
+
+
+
+void AutomationEditor::drawLevelTick( QPainter & _p, int _tick, float _level,
+							bool _is_selected )
+{
+	int grid_bottom = height() - SCROLLBAR_SIZE - 1;
+	const int x = xCoordOfTick( _tick );
+	int rect_width = xCoordOfTick( _tick+1 ) - x;
+
+	// is the level in visible area?
+	if( ( _level >= m_bottomLevel && _level <= m_topLevel )
+			|| ( _level > m_topLevel && m_topLevel >= 0 )
+			|| ( _level < m_bottomLevel && m_bottomLevel <= 0 ) )
+	{
+		int y_start = yCoordOfLevel( _level );
+		int rect_height;
+
+		if( m_y_auto )
+		{
+			int y_end = (int)( grid_bottom
+						+ ( grid_bottom - TOP_MARGIN )
+						* m_minLevel
+						/ ( m_maxLevel - m_minLevel ) );
+
+			rect_height = y_end - y_start;
+		}
+		else
+		{
+			rect_height = (int)( _level * m_y_delta );
+		}
+
+		QColor current_color( 0xFF, 0xB0, 0x00 );
+		if( _is_selected == TRUE )
+		{
+			current_color.setRgb( 0x00, 0x40, 0xC0 );
+		}
+		_p.fillRect( x, y_start, rect_width, rect_height, current_color );
+	}
+	else
+	{
+		printf("not in range\n");
+	}
+}
+
+
+
+
 // responsible for moving/resizing scrollbars after window-resizing
 void AutomationEditor::resizeEvent( QResizeEvent * )
 {
@@ -1858,6 +1985,71 @@ void AutomationEditor::moveButtonToggled()
 
 
 
+void AutomationEditor::discreteButtonToggled()
+{
+	if ( validPattern() )
+	{
+		QMutexLocker m( &m_patternMutex );
+		disableTensionComboBox();
+		m_pattern->setProgressionType(
+				AutomationPattern::DiscreteProgression );
+		engine::getSong()->setModified();
+		update();
+	}
+}
+
+
+
+
+void AutomationEditor::linearButtonToggled()
+{
+	if ( validPattern() )
+	{
+		QMutexLocker m( &m_patternMutex );
+		disableTensionComboBox();
+		m_pattern->setProgressionType(
+					AutomationPattern::LinearProgression );
+		engine::getSong()->setModified();
+		update();
+	}
+}
+
+
+
+
+void AutomationEditor::cubicHermiteButtonToggled()
+{
+	if ( validPattern() )
+	{
+		QMutexLocker m( &m_patternMutex );
+		m_tensionComboBox->setEnabled( true );
+		m_tensionComboBox->setModel( &m_tensionModel );
+		m_tensionComboBox->setToolTip(
+					tr( "Tension value for spline" ) );
+		m_tensionComboBox->setWhatsThis(
+			tr( "A higher tension value may make a smoother curve "
+				"but overshoot some values.  A low tension "
+				"value will cause the slope of the curve to "
+				"level off at each control point." ) );
+		m_pattern->setProgressionType(
+				AutomationPattern::CubicHermiteProgression );
+		engine::getSong()->setModified();
+		update();
+	}
+}
+
+
+
+
+void AutomationEditor::tensionChanged()
+{
+	m_pattern->setTension( m_tensionModel.currentText() );
+	update();
+}
+
+
+
+
 void AutomationEditor::selectAll()
 {
 	QMutexLocker m( &m_patternMutex );

src/gui/AutomationPatternView.cpp

@@ -237,28 +237,39 @@ void AutomationPatternView::paintEvent( QPaintEvent * )
 	QLinearGradient lin2grad( 0, min, 0, max );
 	const QColor cl = QColor( 255, 224, 0 );
 	const QColor cd = QColor( 229, 158, 0 );
-	
+
 	lin2grad.setColorAt( 1, cl );
 	lin2grad.setColorAt( 0, cd );
 
+	// TODO: skip this part for patterns or parts of the pattern that will
+	// not be on the screen
 	for( AutomationPattern::timeMap::const_iterator it =
 						m_pat->getTimeMap().begin();
 					it != m_pat->getTimeMap().end(); ++it )
 	{
-		const float x1 = x_base + it.key() * ppt /
+		if( it+1 == m_pat->getTimeMap().end() )
+		{
+			const float x1 = x_base + it.key() * ppt /
 						midiTime::ticksPerTact();
-		float x2;
-		if( it+1 != m_pat->getTimeMap().end() )
-		{
-		 	x2 = x_base + (it+1).key() * ppt /
-						midiTime::ticksPerTact() + 1;
+			const float x2 = (float)( width() - TCO_BORDER_WIDTH );
+			p.fillRect( QRectF( x1, 0.0f, x2-x1, it.value() ),
+								lin2grad );
+			break;
 		}
-		else
+
+		float *values = m_pat->valuesAfter( it.key() );
+		for( int i = it.key(); i < (it+1).key(); i++ )
 		{
-			x2 = (float)( width() - TCO_BORDER_WIDTH );
+			float value = values[i - it.key()];
+			const float x1 = x_base + i * ppt /
+						midiTime::ticksPerTact();
+			const float x2 = x_base + (i+1) * ppt /
+						midiTime::ticksPerTact();
+
+			p.fillRect( QRectF( x1, 0.0f, x2-x1, value ),
+								lin2grad );
 		}
-		p.fillRect( QRectF( x1, 0.0f, x2-x1, it.value() ),
-							lin2grad );
+		delete [] values;
 	}
 
 	p.resetMatrix();