From 8ba6a5f89e044bfcb893455f6ac146e2eb7e2aac Mon Sep 17 00:00:00 2001
From: Lost Robot <34612565+LostRobotMusic@users.noreply.github.com>
Date: Sat, 18 Feb 2023 07:22:16 -0800
Subject: [PATCH] Draggable effects (#6648)

Reorder effects in Mixer with the mouse via click and drag
---
 include/EffectView.h   |  9 ++++++++
 src/gui/EffectView.cpp | 51 ++++++++++++++++++++++++++++++++++++++----
 2 files changed, 56 insertions(+), 4 deletions(-)

diff --git a/include/EffectView.h b/include/EffectView.h
index 90bb54896..b2b5985ad 100644
--- a/include/EffectView.h
+++ b/include/EffectView.h
@@ -30,6 +30,7 @@
 #include "PluginView.h"
 #include "Effect.h"
 
+class QGraphicsOpacityEffect;
 class QGroupBox;
 class QLabel;
 class QPushButton;
@@ -61,6 +62,11 @@ public:
 	}
 
 	static constexpr int DEFAULT_WIDTH = 215;
+	static constexpr int DEFAULT_HEIGHT = 60;
+	
+	void mouseMoveEvent(QMouseEvent* event) override;
+	void mousePressEvent(QMouseEvent* event) override;
+	void mouseReleaseEvent(QMouseEvent* event) override;
 
 public slots:
 	void editControls();
@@ -90,6 +96,9 @@ private:
 	Knob * m_gate;
 	QMdiSubWindow * m_subWindow;
 	EffectControlDialog * m_controlView;
+	
+	bool m_dragging;
+	QGraphicsOpacityEffect* m_opacityEffect;
 
 } ;
 
diff --git a/src/gui/EffectView.cpp b/src/gui/EffectView.cpp
index fed1ce4e9..f2caaadd5 100644
--- a/src/gui/EffectView.cpp
+++ b/src/gui/EffectView.cpp
@@ -23,9 +23,11 @@
  *
  */
 
+#include <QGraphicsOpacityEffect>
+#include <QLayout>
+#include <QMouseEvent>
 #include <QPushButton>
 #include <QPainter>
-#include <QLayout>
 
 #include "EffectView.h"
 #include "DummyEffect.h"
@@ -47,9 +49,10 @@ EffectView::EffectView( Effect * _model, QWidget * _parent ) :
 	PluginView( _model, _parent ),
 	m_bg( embed::getIconPixmap( "effect_plugin" ) ),
 	m_subWindow( nullptr ),
-	m_controlView( nullptr )
+	m_controlView(nullptr),
+	m_dragging(false)
 {
-	setFixedSize( EffectView::DEFAULT_WIDTH, 60 );
+	setFixedSize(EffectView::DEFAULT_WIDTH, EffectView::DEFAULT_HEIGHT);
 
 	// Disable effects that are of type "DummyEffect"
 	bool isEnabled = !dynamic_cast<DummyEffect *>( effect() );
@@ -116,7 +119,10 @@ EffectView::EffectView( Effect * _model, QWidget * _parent ) :
 			m_subWindow->hide();
 		}
 	}
-
+	
+	m_opacityEffect = new QGraphicsOpacityEffect(this);
+	m_opacityEffect->setOpacity(1);
+	setGraphicsEffect(m_opacityEffect);
 
 	//move above vst effect view creation
 	//setModel( _model );
@@ -208,6 +214,43 @@ void EffectView::contextMenuEvent( QContextMenuEvent * )
 
 
 
+void EffectView::mousePressEvent(QMouseEvent* event)
+{
+	if (event->button() == Qt::LeftButton)
+	{
+		m_dragging = true;
+		m_opacityEffect->setOpacity(0.3);
+		QCursor c(Qt::SizeVerCursor);
+		QApplication::setOverrideCursor(c);
+		update();
+	}
+}
+
+void EffectView::mouseReleaseEvent(QMouseEvent* event)
+{
+	if (event->button() == Qt::LeftButton)
+	{
+		m_dragging = false;
+		m_opacityEffect->setOpacity(1);
+		QApplication::restoreOverrideCursor();
+		update();
+	}
+}
+
+void EffectView::mouseMoveEvent(QMouseEvent* event)
+{
+	if (!m_dragging) { return; }
+	if (event->pos().y() < 0)
+	{
+		moveUp();
+	}
+	else if (event->pos().y() > EffectView::DEFAULT_HEIGHT)
+	{
+		moveDown();
+	}
+}
+
+
 
 void EffectView::paintEvent( QPaintEvent * )
 {