Add the ability to zoom and scroll horizontally in the pattern editor

include/PatternEditor.h

@@ -27,19 +27,24 @@
 
 #include "Editor.h"
 #include "TrackContainerView.h"
+#include "AutomatableModel.h"
+
+class QLabel;
+class QScrollBar;
 
 namespace lmms
 {
 
+class IntModel;
 class PatternStore;
 
 namespace gui
 {
 
+class AutomatableSlider;
 class ComboBox;
 class TimeLineWidget;
 
-
 class PatternEditor : public TrackContainerView
 {
 	Q_OBJECT
@@ -65,18 +70,43 @@ public slots:
 	void cloneClip();
 	void updateMaxSteps();
 
+signals:
+	void zoomLevelChanged();
+	void offsetValueChanged();
+	void zoomControlsVisibilityChanged( bool show );
+
+protected:
+	double getZoom() const
+	{
+		// The zoom level is calculated such as exactly one bar is visible when the zoom slider is at its maximum value,
+		// and the whole pattern is visible when the zoom slider is at its minimum value.
+		return 1 + m_zoomingModel->value() * ( m_maxClipLength / TimePos::ticksPerBar() - 1 ) / static_cast<double>(m_zoomingModel->maxValue());
+	}
+
 protected slots:
 	void dropEvent(QDropEvent * de ) override;
 	void resizeEvent(QResizeEvent* de) override;
 	void updatePosition();
 	void updatePixelsPerBar();
+	void updateScrollBar();
 
 private:
+	void wheelEvent( QWheelEvent * we ) override;
+
+	IntModel* m_zoomingModel;
+	QScrollBar* m_leftRightScroll;
+
 	PatternStore* m_ps;
 	TimeLineWidget* m_timeLine;
 	int m_trackHeadWidth;
 	tick_t m_maxClipLength;
 	void makeSteps( bool clone );
+
+private slots:
+	void zoomingChanged();
+	void horizontalScrollChanged();
+
+	friend class PatternEditorWindow;
 };
 
 
@@ -89,14 +119,27 @@ Q_OBJECT
 
 	QSize sizeHint() const override;
 
+	double zoomLevel() const
+	{
+		return m_editor->getZoom();
+	}
+
+	double horizontalScrollValue() const;
+
 	PatternEditor* m_editor;
 
 public slots:
 	void play() override;
 	void stop() override;
 
+	void showZoomControls( bool show );
+
 private:
+	AutomatableSlider * m_zoomingSlider;
 	ComboBox* m_patternComboBox;
+
+	QAction* m_zoomIconAction;
+	QAction* m_zoomSliderAction;
 };
 
 

src/gui/clips/ClipView.cpp

@@ -42,6 +42,7 @@
 #include "KeyboardShortcuts.h"
 #include "lmms_math.h"
 #include "MidiClipView.h"
+#include "PatternEditor.h"
 #include "PatternClip.h"
 #include "PatternStore.h"
 #include "Song.h"
@@ -119,6 +120,8 @@ ClipView::ClipView( Clip * clip,
 	connect( m_clip, SIGNAL(lengthChanged()),
 			this, SLOT(updateLength()));
 	connect(getGUI()->songEditor()->m_editor, &SongEditor::pixelsPerBarChanged, this, &ClipView::updateLength);
+	connect(getGUI()->patternEditor()->m_editor, &PatternEditor::zoomLevelChanged, this, &ClipView::updateLength);
+	connect(getGUI()->patternEditor()->m_editor, &PatternEditor::offsetValueChanged, this, &ClipView::updatePosition);
 	connect( m_clip, SIGNAL(positionChanged()),
 			this, SLOT(updatePosition()));
 	connect( m_clip, SIGNAL(destroyedClip()), this, SLOT(close()));
@@ -314,7 +317,7 @@ void ClipView::updateLength()
 {
 	if( fixedClips() )
 	{
-		setFixedWidth( parentWidget()->width() );
+		setFixedWidth( parentWidget()->width() * getGUI()->patternEditor()->zoomLevel() );
 	}
 	else
 	{
@@ -337,10 +340,17 @@ void ClipView::updateLength()
  */
 void ClipView::updatePosition()
 {
-	m_trackView->getTrackContentWidget()->changePosition();
-	// moving a Clip can result in change of song-length etc.,
-	// therefore we update the track-container
-	m_trackView->trackContainerView()->update();
+	if ( fixedClips() )
+	{
+		move( -parentWidget()->width() * getGUI()->patternEditor()->horizontalScrollValue(), 0 );
+	}
+	else
+	{	
+		m_trackView->getTrackContentWidget()->changePosition();
+		// moving a Clip can result in change of song-length etc.,
+		// therefore we update the track-container
+		m_trackView->trackContainerView()->update();
+	}
 }
 
 void ClipView::selectColor()

src/gui/clips/MidiClipView.cpp

@@ -498,7 +498,8 @@ void MidiClipView::wheelEvent(QWheelEvent * we)
 	const auto pos = we->position().toPoint();
 	if(m_clip->m_clipType == MidiClip::Type::BeatClip &&
 				(fixedClips() || pixelsPerBar() >= 96) &&
-				pos.y() > height() - m_stepBtnOff.height())
+				pos.y() > height() - m_stepBtnOff.height() &&
+				!(we->modifiers() & (Qt::ControlModifier | Qt::ShiftModifier)))
 	{
 //	get the step number that was wheeled on and
 //	do calculations in floats to prevent rounding errors...

src/gui/editors/PatternEditor.cpp

@@ -25,8 +25,12 @@
 #include "PatternEditor.h"
 
 #include <QAction>
+#include <QLabel>
+#include <QScrollBar>
+#include <QSlider>
 #include <QVBoxLayout>
 
+#include "AutomatableSlider.h"
 #include "ClipView.h"
 #include "ComboBox.h"
 #include "DataFile.h"
@@ -48,6 +52,7 @@ namespace lmms::gui
 
 PatternEditor::PatternEditor(PatternStore* ps) :
 	TrackContainerView(ps),
+	m_zoomingModel(new IntModel(0, 0, 100, nullptr, tr("Zoom"))),
 	m_ps(ps),
 	m_trackHeadWidth(ConfigManager::inst()->value("ui", "compacttrackbuttons").toInt() == 1
 		? DEFAULT_SETTINGS_WIDGET_WIDTH_COMPACT + TRACK_OP_WIDTH_COMPACT
@@ -60,12 +65,33 @@ PatternEditor::PatternEditor(PatternStore* ps) :
 		Engine::getSong()->getTimeline(Song::PlayMode::Pattern),
 		m_currentPosition, this
 	);
+	connect(this, &TrackContainerView::positionChanged, m_timeLine, qOverload<>(&QWidget::update));
 	connect(m_timeLine->timeline(), &Timeline::positionChanged, this, &PatternEditor::updatePosition);
 	static_cast<QVBoxLayout*>(layout())->insertWidget(0, m_timeLine);
 
 	connect(m_ps, &PatternStore::trackUpdated,
 		this, &PatternEditor::updateMaxSteps);
 
+	// Set up zooming model
+	m_zoomingModel->setParent(this);
+	m_zoomingModel->setJournalling(false);
+	connect(m_zoomingModel, SIGNAL(dataChanged()), this, SLOT(zoomingChanged()));
+
+	connect(Engine::getSong(), &Song::stopped, this, [this]()
+	{
+		// Show zoom controls again as they are hidden during playback
+		emit zoomControlsVisibilityChanged( m_maxClipLength / TimePos::ticksPerBar() > 1 );
+	});
+
+	// Set up horizontal scroll bar
+	m_leftRightScroll = new QScrollBar( Qt::Horizontal, this );
+	m_leftRightScroll->setMinimum(0);
+	m_leftRightScroll->setMaximum(0);
+	m_leftRightScroll->setSingleStep(1);
+	m_leftRightScroll->setPageStep( m_maxClipLength );
+	static_cast<QVBoxLayout *>( layout() )->addWidget( m_leftRightScroll );
+	connect(m_leftRightScroll, SIGNAL(valueChanged(int)),this, SLOT(horizontalScrollChanged()));
+
 	setFocusPolicy(Qt::StrongFocus);
 	setFocus();
 }
@@ -206,7 +232,7 @@ void PatternEditor::updatePixelsPerBar()
 	setPixelsPerBar(m_maxClipLength != 0
 		? (width() - m_trackHeadWidth) * TimePos::ticksPerBar() / m_maxClipLength
 		: (width() - m_trackHeadWidth));
-	m_timeLine->setPixelsPerBar(pixelsPerBar());
+	m_timeLine->setPixelsPerBar(pixelsPerBar() * getZoom());
 }
 
 void PatternEditor::updateMaxSteps()
@@ -223,6 +249,41 @@ void PatternEditor::updateMaxSteps()
 		}
 	}
 	updatePixelsPerBar();
+	updateScrollBar();
+
+	// Show zoom controls if the pattern is longer than one bar, hide them otherwise as they would have no effect anyway
+	emit zoomControlsVisibilityChanged( m_maxClipLength / TimePos::ticksPerBar() > 1 );
+}
+
+
+void PatternEditor::updateScrollBar()
+{
+	m_leftRightScroll->setPageStep( m_maxClipLength / getZoom() );
+	m_leftRightScroll->setMaximum( m_maxClipLength - m_leftRightScroll->pageStep() );
+}
+
+
+void PatternEditor::wheelEvent( QWheelEvent * we )
+{
+	const auto posX = we->position().toPoint().x();
+	if ((we->modifiers() & Qt::ControlModifier) && (posX > m_trackHeadWidth))
+	{
+		// move zoom slider (pixelsPerBar will change automatically)
+		int step = we->modifiers() & Qt::ShiftModifier ? 1 : 5;
+		// when Alt is pressed, wheelEvent returns delta for x coordinate (mimics horizontal mouse wheel)
+		int direction = (we->angleDelta().y() + we->angleDelta().x()) > 0 ? 1 : -1;
+		m_zoomingModel->incValue(step * direction);
+	}
+	else if (we->modifiers() & Qt::ShiftModifier)
+	{
+		m_leftRightScroll->setValue( m_leftRightScroll->value() - we->angleDelta().y() );
+	}
+	else
+	{
+		we->ignore();
+		return;
+	}
+	we->accept();
 }
 
 
@@ -271,6 +332,23 @@ void PatternEditor::cloneClip()
 }
 
 
+void PatternEditor::zoomingChanged()
+{
+	updatePixelsPerBar();
+	updateScrollBar();
+
+	emit zoomLevelChanged();
+}
+
+void PatternEditor::horizontalScrollChanged()
+{
+	m_currentPosition = TimePos( m_leftRightScroll->value() );
+	updatePosition();
+
+	emit offsetValueChanged();
+}
+
+
 
 
 PatternEditorWindow::PatternEditorWindow(PatternStore* ps) :
@@ -327,6 +405,23 @@ PatternEditorWindow::PatternEditorWindow(PatternStore* ps) :
 	stretch->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
 	trackAndStepActionsToolBar->addWidget(stretch);
 
+	QLabel* zoom_lbl = new QLabel(m_toolBar);
+	zoom_lbl->setPixmap( embed::getIconPixmap( "zoom" ) );
+
+	// Set slider zoom
+	m_zoomingSlider = new AutomatableSlider(m_toolBar, tr("Zoom"));
+	m_zoomingSlider->setModel(m_editor->m_zoomingModel);
+	m_zoomingSlider->setOrientation(Qt::Horizontal);
+	m_zoomingSlider->setPageStep(1);
+	m_zoomingSlider->setFocusPolicy(Qt::NoFocus);
+	m_zoomingSlider->setFixedSize(100, 26);
+	m_zoomingSlider->setToolTip(tr("Zoom"));
+	m_zoomingSlider->setContextMenuPolicy(Qt::NoContextMenu);
+	connect(m_editor, &PatternEditor::zoomControlsVisibilityChanged, this, &PatternEditorWindow::showZoomControls);
+
+	m_zoomIconAction =  trackAndStepActionsToolBar->addWidget(zoom_lbl);
+	m_zoomSliderAction = trackAndStepActionsToolBar->addWidget(m_zoomingSlider);
+	showZoomControls( false );
 
 	// Step actions
 	trackAndStepActionsToolBar->addAction(embed::getIconPixmap("step_btn_remove"), tr("Remove steps"),
@@ -358,15 +453,28 @@ QSize PatternEditorWindow::sizeHint() const
 }
 
 
+double PatternEditorWindow::horizontalScrollValue() const
+{
+	return m_editor->m_leftRightScroll->value() / static_cast<double>(m_editor->m_leftRightScroll->pageStep());
+}
+
+
 void PatternEditorWindow::play()
 {
+	showZoomControls( false );
+
 	if (Engine::getSong()->playMode() != Song::PlayMode::Pattern)
 	{
+		m_zoomingSlider->setValue(0);
 		Engine::getSong()->playPattern();
 	}
 	else
 	{
 		Engine::getSong()->togglePause();
+		if ( Engine::getSong()->isPaused())
+		{
+			showZoomControls( true );
+		}
 	}
 }
 
@@ -377,4 +485,14 @@ void PatternEditorWindow::stop()
 }
 
 
+void PatternEditorWindow::showZoomControls( bool show )
+{
+	if ( !Engine::getSong()->isPlaying() )
+	{
+		m_zoomIconAction->setVisible( show );
+		m_zoomSliderAction->setVisible( show );
+	}
+}
+
+
 } // namespace lmms::gui

src/gui/tracks/TrackContentWidget.cpp

@@ -241,7 +241,6 @@ void TrackContentWidget::changePosition( const TimePos & newPos )
 		{
 			if (clipView->getClip()->startPosition().getBar() == curPattern)
 			{
-				clipView->move(0, clipView->y());
 				clipView->raise();
 				clipView->show();
 			}