Add AbstractConnectionPainter to enable custom connections

CMakeLists.txt

@@ -92,6 +92,7 @@ set(CPP_SOURCE_FILES
 )
 
 set(HPP_HEADER_FILES
+  include/QtNodes/internal/AbstractConnectionPainter.hpp
   include/QtNodes/internal/AbstractGraphModel.hpp
   include/QtNodes/internal/AbstractNodeGeometry.hpp
   include/QtNodes/internal/AbstractNodePainter.hpp

include/QtNodes/AbstractConnectionPainter

@@ -0,0 +1 @@
+#include "internal/AbstractConnectionPainter.hpp"

include/QtNodes/internal/AbstractConnectionPainter.hpp

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <QPainter>
+
+#include "Export.hpp"
+
+class QPainter;
+
+namespace QtNodes {
+
+class ConnectionGraphicsObject;
+
+/// Class enables custom painting for connections.
+class NODE_EDITOR_PUBLIC AbstractConnectionPainter
+{
+public:
+    virtual ~AbstractConnectionPainter() = default;
+
+    /**
+   * Reimplement this function in order to have a custom connection painting.
+   *
+   */
+    virtual void paint(QPainter *painter, ConnectionGraphicsObject const &cgo) const = 0;
+
+    virtual QPainterPath getPainterStroke(ConnectionGraphicsObject const &cgo) const = 0;
+};
+} // namespace QtNodes

include/QtNodes/internal/BasicGraphicsScene.hpp

@@ -21,6 +21,7 @@ class QUndoStack;
 
 namespace QtNodes {
 
+class AbstractConnectionPainter;
 class AbstractGraphModel;
 class AbstractNodePainter;
 class ConnectionGraphicsObject;
@@ -49,8 +50,12 @@ class NODE_EDITOR_PUBLIC BasicGraphicsScene : public QGraphicsScene
 
     AbstractNodePainter &nodePainter();
 
+    AbstractConnectionPainter &connectionPainter();
+
     void setNodePainter(std::unique_ptr<AbstractNodePainter> newPainter);
 
+    void setConnectionPainter(std::unique_ptr<AbstractConnectionPainter> newPainter);
+
     QUndoStack &undoStack();
 
 public:
@@ -168,6 +173,8 @@ public Q_SLOTS:
 
     std::unique_ptr<AbstractNodePainter> _nodePainter;
 
+    std::unique_ptr<AbstractConnectionPainter> _connectionPainter;
+
     bool _nodeDrag;
 
     QUndoStack *_undoStack;

src/BasicGraphicsScene.cpp

@@ -5,6 +5,7 @@
 #include "ConnectionIdUtils.hpp"
 #include "DefaultHorizontalNodeGeometry.hpp"
 #include "DefaultNodePainter.hpp"
+#include "ConnectionPainter.hpp"
 #include "DefaultVerticalNodeGeometry.hpp"
 #include "GraphicsView.hpp"
 #include "NodeGraphicsObject.hpp"
@@ -36,6 +37,7 @@ BasicGraphicsScene::BasicGraphicsScene(AbstractGraphModel &graphModel, QObject *
     , _graphModel(graphModel)
     , _nodeGeometry(std::make_unique<DefaultHorizontalNodeGeometry>(_graphModel))
     , _nodePainter(std::make_unique<DefaultNodePainter>())
+    , _connectionPainter(std::make_unique<ConnectionPainter>())
     , _nodeDrag(false)
     , _undoStack(new QUndoStack(this))
     , _orientation(Qt::Horizontal)
@@ -101,11 +103,21 @@ AbstractNodePainter &BasicGraphicsScene::nodePainter()
     return *_nodePainter;
 }
 
+AbstractConnectionPainter &BasicGraphicsScene::connectionPainter()
+{
+    return *_connectionPainter;
+}
+
 void BasicGraphicsScene::setNodePainter(std::unique_ptr<AbstractNodePainter> newPainter)
 {
     _nodePainter = std::move(newPainter);
 }
 
+void BasicGraphicsScene::setConnectionPainter(std::unique_ptr<AbstractConnectionPainter> newPainter)
+{
+    _connectionPainter = std::move(newPainter);
+}
+
 QUndoStack &BasicGraphicsScene::undoStack()
 {
     return *_undoStack;

src/ConnectionGraphicsObject.cpp

@@ -128,7 +128,7 @@ QPainterPath ConnectionGraphicsObject::shape() const
     //return path;
 
 #else
-    return ConnectionPainter::getPainterStroke(*this);
+    return nodeScene()->connectionPainter().getPainterStroke(*this);
 #endif
 }
 
@@ -198,7 +198,7 @@ void ConnectionGraphicsObject::paint(QPainter *painter,
 
     painter->setClipRect(option->exposedRect);
 
-    ConnectionPainter::paint(painter, *this);
+    nodeScene()->connectionPainter().paint(painter, *this);
 }
 
 void ConnectionGraphicsObject::mousePressEvent(QGraphicsSceneMouseEvent *event)

src/ConnectionPainter.cpp

@@ -11,7 +11,7 @@
 
 namespace QtNodes {
 
-static QPainterPath cubicPath(ConnectionGraphicsObject const &connection)
+QPainterPath ConnectionPainter::cubicPath(ConnectionGraphicsObject const &connection)
 {
     QPointF const &in = connection.endPoint(PortType::In);
     QPointF const &out = connection.endPoint(PortType::Out);
@@ -26,7 +26,7 @@ static QPainterPath cubicPath(ConnectionGraphicsObject const &connection)
     return cubic;
 }
 
-QPainterPath ConnectionPainter::getPainterStroke(ConnectionGraphicsObject const &connection)
+QPainterPath ConnectionPainter::getPainterStroke(ConnectionGraphicsObject const &connection) const
 {
     auto cubic = cubicPath(connection);
 
@@ -78,15 +78,15 @@ static void debugDrawing(QPainter *painter, ConnectionGraphicsObject const &cgo)
 
 #endif
 
-static void drawSketchLine(QPainter *painter, ConnectionGraphicsObject const &cgo)
+void ConnectionPainter::drawSketchLine(QPainter *painter, ConnectionGraphicsObject const &cgo)
 {
     ConnectionState const &state = cgo.connectionState();
 
     if (state.requiresPort()) {
         auto const &connectionStyle = QtNodes::StyleCollection::connectionStyle();
 
         QPen pen;
-        pen.setWidth(connectionStyle.constructionLineWidth());
+        pen.setWidth(static_cast<int>(connectionStyle.constructionLineWidth()));
         pen.setColor(connectionStyle.constructionColor());
         pen.setStyle(Qt::DashLine);
 
@@ -100,7 +100,7 @@ static void drawSketchLine(QPainter *painter, ConnectionGraphicsObject const &cg
     }
 }
 
-static void drawHoveredOrSelected(QPainter *painter, ConnectionGraphicsObject const &cgo)
+void ConnectionPainter::drawHoveredOrSelected(QPainter *painter, ConnectionGraphicsObject const &cgo)
 {
     bool const hovered = cgo.connectionState().hovered();
     bool const selected = cgo.isSelected();
@@ -112,7 +112,7 @@ static void drawHoveredOrSelected(QPainter *painter, ConnectionGraphicsObject co
         double const lineWidth = connectionStyle.lineWidth();
 
         QPen pen;
-        pen.setWidth(2 * lineWidth);
+        pen.setWidth(static_cast<int>(2 * lineWidth));
         pen.setColor(selected ? connectionStyle.selectedHaloColor()
                               : connectionStyle.hoveredColor());
 
@@ -125,7 +125,7 @@ static void drawHoveredOrSelected(QPainter *painter, ConnectionGraphicsObject co
     }
 }
 
-static void drawNormalLine(QPainter *painter, ConnectionGraphicsObject const &cgo)
+void ConnectionPainter::drawNormalLine(QPainter *painter, ConnectionGraphicsObject const &cgo)
 {
     ConnectionState const &state = cgo.connectionState();
 
@@ -227,7 +227,7 @@ static void drawNormalLine(QPainter *painter, ConnectionGraphicsObject const &cg
     }
 }
 
-void ConnectionPainter::paint(QPainter *painter, ConnectionGraphicsObject const &cgo)
+void ConnectionPainter::paint(QPainter *painter, ConnectionGraphicsObject const &cgo) const
 {
     drawHoveredOrSelected(painter, cgo);
 

src/ConnectionPainter.hpp

@@ -3,19 +3,25 @@
 #include <QtGui/QPainter>
 #include <QtGui/QPainterPath>
 
+#include "AbstractConnectionPainter.hpp"
 #include "Definitions.hpp"
 
 namespace QtNodes {
 
 class ConnectionGeometry;
 class ConnectionGraphicsObject;
 
-class ConnectionPainter
+class ConnectionPainter : public AbstractConnectionPainter
 {
 public:
-    static void paint(QPainter *painter, ConnectionGraphicsObject const &cgo);
+    void paint(QPainter *painter, ConnectionGraphicsObject const &cgo) const override;
+    QPainterPath getPainterStroke(ConnectionGraphicsObject const &cgo) const override;
 
-    static QPainterPath getPainterStroke(ConnectionGraphicsObject const &cgo);
+private:
+    static QPainterPath cubicPath(ConnectionGraphicsObject const &connection);
+    static void drawSketchLine(QPainter *painter, ConnectionGraphicsObject const &cgo);
+    static void drawHoveredOrSelected(QPainter *painter, ConnectionGraphicsObject const &cgo);
+    static void drawNormalLine(QPainter *painter, ConnectionGraphicsObject const &cgo);
 };
 
 } // namespace QtNodes