Add BarModelEditor and improve layouts

Add the new class `BarModelEditor` which is intended to become a new way
to adjust values of float models.

Simplify the layout in `LadspaMatrixControlDialog` by removing some
nested layouts. Remove the "Parameters" column.

Adjust `LadspaMatrixControlView` to implement the following changes:
* Show the name of the control next to toggle buttons (`LedCheckBox`).
* Use the new `BarModelEditor` for integer and float types.
* SHow the name of the control next to time based parameters that use
`TempoSyncKnob`.

The names are shown so that the "Parameters" column can be removed.

Technical details
------------------
The class `LadspaMatrixControlDialog` now creates a widget that contains
the matrix layout with the controls. This widget is then added to a
scroll area. The layout is populated in the new method
`arrangeControls`.

Add some helper methods to `LadspaMatrixControlDialog` which retrieve
the `LadspaControls` instance and the number of channels.

Add the implementation of `BarModelEditor` to `src/gui/CMakeLists.txt`.

TODOs
------
Extract common code out of the `Knob` class so that it can be reused by
`BarModelEditor`.

src/gui/CMakeLists.txt

@@ -95,6 +95,7 @@ SET(LMMS_SRCS
 
 	gui/widgets/AutomatableButton.cpp
 	gui/widgets/AutomatableSlider.cpp
+	gui/widgets/BarModelEditor.cpp
 	gui/widgets/CPULoadWidget.cpp
 	gui/widgets/CaptionMenu.cpp
 	gui/widgets/ComboBox.cpp

src/gui/LadspaMatrixControlView.cpp

@@ -29,10 +29,12 @@
 #include "LadspaControl.h"
 
 #include "LadspaBase.h"
+#include "BarModelEditor.h"
 #include "LedCheckBox.h"
 #include "TempoSyncKnob.h"
 
 #include <QLayout>
+#include <QLabel>
 
 
 namespace lmms::gui
@@ -51,12 +53,13 @@ LadspaMatrixControlView::LadspaMatrixControlView(QWidget * parent,
 	Knob * knob = nullptr;
 
 	buffer_data_t dataType = m_ladspaControl->port()->data_type;
+	QString const name = m_ladspaControl->port()->name;
 	switch (dataType)
 	{
 		case TOGGLED:
 		{
 			LedCheckBox * toggle = new LedCheckBox(
-				"", this, QString(), LedCheckBox::Green);
+				name, this, QString(), LedCheckBox::Green);
 			toggle->setModel(m_ladspaControl->toggledModel());
 			layout->addWidget(toggle);
 			setFixedSize(toggle->width(), toggle->height());
@@ -65,16 +68,20 @@ LadspaMatrixControlView::LadspaMatrixControlView(QWidget * parent,
 
 		case INTEGER:
 		case FLOATING:
-			knob = new Knob(knobBright_26, this, m_ladspaControl->port()->name);
+			/*knob = new Knob(knobBright_26, this, name);
 			knob->setModel(m_ladspaControl->knobModel());
+			knob->setLabel(name);*/
+			layout->addWidget(new BarModelEditor(name, m_ladspaControl->knobModel(), this));
 			break;
 
 		case TIME:
-			knob = new TempoSyncKnob(knobBright_26, this, m_ladspaControl->port()->name);
+			knob = new TempoSyncKnob(knobBright_26, this, name);
 			knob->setModel(m_ladspaControl->tempoSyncKnobModel());
+			knob->setLabel(name);
 			break;
 
 		default:
+			layout->addWidget(new QLabel(tr("%1 (unsupported)").arg(name), this));
 			break;
 	}
 

src/gui/widgets/BarModelEditor.cpp

@@ -0,0 +1,115 @@
+#include <BarModelEditor.h>
+
+#include "CaptionMenu.h"
+
+#include <QPainter>
+#include <QInputDialog>
+
+
+namespace lmms::gui
+{
+
+BarModelEditor::BarModelEditor(QString text, FloatModel * floatModel, QWidget * parent) :
+	QWidget(parent),
+	FloatModelView( floatModel, this ),
+	m_text(text)
+{
+	connectToModelSignals();
+}
+
+QSizePolicy BarModelEditor::sizePolicy() const
+{
+	return QSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
+}
+
+QSize BarModelEditor::minimumSizeHint() const
+{
+	auto const fm = fontMetrics();
+	return QSize(200, fm.height() * 1.3);
+}
+
+QSize BarModelEditor::sizeHint() const
+{
+	return minimumSizeHint();
+}
+
+void BarModelEditor::paintEvent(QPaintEvent *event)
+{
+	QWidget::paintEvent(event);
+
+	QColor const background(30, 40, 51);
+	QColor const foreground(3, 94, 97);
+	QColor const textColor(14, 192, 198);
+
+	auto const * mod = model();
+	auto const minValue = mod->minValue();
+	auto const maxValue = mod->maxValue();
+	auto const range = maxValue - minValue;
+
+	QRect const r = rect();
+
+	QPainter painter(this);
+	painter.setPen(background);
+	painter.setBrush(background);
+	painter.drawRect(r);
+
+	// Compute the percentage
+	// min + x * (max - min) = v <=> x = (v - min) / (max - min)
+	auto const percentage = range == 0 ? 1. : (mod->value() - minValue) / range;
+
+	int const margin = 2;
+	QMargins const margins(margin, margin, margin, margin);
+	QRect const valueRect = r.marginsRemoved(margins);
+
+	painter.setPen(foreground);
+	painter.setBrush(foreground);
+	painter.drawRect(QRect(valueRect.topLeft(), QPoint(valueRect.width() * percentage, valueRect.height())));
+
+	// Draw text
+	QRect const textRect = valueRect.marginsRemoved(margins);
+	painter.setPen(textColor);
+	painter.drawText(textRect, m_text);
+}
+
+void BarModelEditor::contextMenuEvent(QContextMenuEvent * me)
+{
+	CaptionMenu contextMenu(model()->displayName(), this);
+
+	addDefaultActions(&contextMenu);
+
+	contextMenu.addSeparator();
+	contextMenu.exec(QCursor::pos());
+}
+
+void BarModelEditor::mouseDoubleClickEvent(QMouseEvent * me)
+{
+	bool ok;
+
+	float new_val = QInputDialog::getDouble(
+		this, tr("Set value"),
+		tr("Please enter a new value between "
+		   "%1 and %2:").
+		arg(model()->minValue()).
+		arg(model()->maxValue()),
+		model()->getRoundedValue(),
+		model()->minValue(),
+		model()->maxValue(), model()->getDigitCount(), &ok);
+
+	if (ok)
+	{
+		model()->setValue(new_val);
+	}
+}
+
+void BarModelEditor::connectToModelSignals()
+{
+	auto * m = model();
+	if(m)
+	{
+		// TODO The first connection does a "friendly" update in Knob. Do we also have to do this?
+		QObject::connect(m, SIGNAL(dataChanged()), this, SLOT(update()));
+		QObject::connect(m ,SIGNAL(propertiesChanged()), this, SLOT(update()));
+	}
+}
+
+}