There are more than 1 slots available now.

code/studio/src/plugins/gui_editor/expression_editor.cpp

@@ -87,7 +87,12 @@ void ExpressionEditor::onDeleteSelection()
 		ExpressionNode *node = dynamic_cast< ExpressionNode* >( item );
 		if( node != NULL )		
 		{
-			ExpressionLink *link = node->link();
+			ExpressionLink *link = NULL;
+
+			int c = node->slotCount();
+			for( int i = 0; i < c; i++ )
+			{
+				link = node->link( i );
 				if( link != NULL )
 				{
 					link->unlink();
@@ -95,6 +100,7 @@ void ExpressionEditor::onDeleteSelection()
 					delete link;
 				}
 			}
+		}
 
 		m_scene->removeItem( item );
 		delete item;
@@ -113,7 +119,7 @@ void ExpressionEditor::onLinkItems()
 	ExpressionNode *from = static_cast< ExpressionNode* >( l[ 0 ] );
 	ExpressionNode *to = static_cast< ExpressionNode* >( l[ 1 ] );
 
-	if( ( from->link() != NULL ) || ( to->link() != NULL ) )
+	if( ( from->link( 0 ) != NULL ) || ( to->link( 0 ) != NULL ) )
 	{
 		QMessageBox::information( this,
 									tr( "Failed to link nodes" ),
@@ -122,7 +128,7 @@ void ExpressionEditor::onLinkItems()
 	}
 
 	ExpressionLink *link = new ExpressionLink();
-	link->link( from, to );
+	link->link( from, to, 0, 0 );
 
 	m_scene->addItem( link );
 }

code/studio/src/plugins/gui_editor/expression_link.cpp

@@ -35,20 +35,23 @@ ExpressionLink::~ExpressionLink()
 	unlink();
 }
 
-void ExpressionLink::link( ExpressionNode *from, ExpressionNode *to )
+void ExpressionLink::link( ExpressionNode *from, ExpressionNode *to, int fromSlot, int toSlot )
 {
 	m_from = from;
 	m_to = to;
-	m_from->setLink( this );
+	m_from->setLink( this, fromSlot );
-	m_to->setLink( this );
+	m_to->setLink( this, toSlot );
+
+	m_fromSlot = fromSlot;
+	m_toSlot = toSlot;
 
 	nodeMoved();
 }
 
 void ExpressionLink::unlink()
 {
-	m_from->setLink( NULL );
+	m_from->setLink( NULL, m_fromSlot );
-	m_to->setLink( NULL );
+	m_to->setLink( NULL, m_toSlot );
 }
 
 void ExpressionLink::nodeMoved()

code/studio/src/plugins/gui_editor/expression_link.h

@@ -29,7 +29,7 @@ public:
 	ExpressionLink( QGraphicsItem *parent = NULL );
 	~ExpressionLink();
 
-	void link( ExpressionNode *from, ExpressionNode *to );
+	void link( ExpressionNode *from, ExpressionNode *to, int fromSlot, int toSlot );
 	void unlink();
 
 	void nodeMoved();
@@ -40,6 +40,8 @@ private:
 	ExpressionNode *m_from;
 	ExpressionNode *m_to;
 
+	int m_fromSlot;
+	int m_toSlot;
 };
 
 #endif

code/studio/src/plugins/gui_editor/expression_node.cpp

@@ -98,12 +98,13 @@ private:
 ExpressionNode::ExpressionNode( QGraphicsItem *parent ) :
 QGraphicsItem( parent )
 {
-	m_link = NULL;
-	
 	m_w = 100;
 	m_h = 100;
 
 	createSlots();
+
+	for( int i = 0; i < 4; i++ )
+		m_links.push_back( NULL );
 }
 
 ExpressionNode::~ExpressionNode()
@@ -168,10 +169,26 @@ QPointF ExpressionNode::slotPos( int slot ) const
 	return mp;
 }
 
+void ExpressionNode::setLink( ExpressionLink *link, int slot )
+{
+	m_links[ slot ] = link;
+}
+
+ExpressionLink* ExpressionNode::link( int slot ) const
+{
+	return m_links[ slot ];
+}
+
 void ExpressionNode::mouseMoveEvent( QGraphicsSceneMouseEvent *e )
 {
-	if( m_link != NULL )
+	for( int i = 0; i < 4; i++ )
-		m_link->nodeMoved();
+	{
+		ExpressionLink *link = m_links[ i ];
+		if( link == NULL )
+			continue;
+
+		link->nodeMoved();
+	}
 
 	QGraphicsItem::mouseMoveEvent( e );
 }

code/studio/src/plugins/gui_editor/expression_node.h

@@ -35,11 +35,13 @@ public:
 	QRectF boundingRect() const;
 	void paint( QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget );
 
-	void setLink( ExpressionLink *link ){ m_link = link; }
+	void setLink( ExpressionLink *link, int slot );
-	ExpressionLink* link() const{ return m_link; }
+	ExpressionLink* link( int slot ) const;
 
 	QPointF slotPos( int slot ) const;
 
+	int slotCount() const{ return m_slots.count(); }
+
 protected:
 	void mouseMoveEvent( QGraphicsSceneMouseEvent *e );
 
@@ -47,12 +49,11 @@ private:
 	void createSlots();
 	void paintSlots( QPainter *painter );
 
-	ExpressionLink *m_link;
-
 	qreal m_w;
 	qreal m_h;
 
 	QList< NodeSlot* > m_slots;
+	QList< ExpressionLink* > m_links;
 };
 
 #endif