fixes to make the source compile

nodes/node.cpp

@@ -38,6 +38,11 @@ int Node::ParameterCount()
   return parameters_.size();
 }
 
+double Node::Time()
+{
+  return 0;
+}
+
 void Node::Process(rational time)
 {
   Q_UNUSED(time)

nodes/node.h

@@ -22,13 +22,12 @@ public:
   NodeIO* Parameter(int i);
   int ParameterCount();
 
+  double Time();
+
   NodeGraph* ParentGraph();
 
   const QPointF& pos();
 
-protected:
-  virtual void GLContextChangeEvent();
-
 public slots:
   void SetPos(const QPointF& pos);