Simple drawing example.

src/visual_elements/GeometryNode.h

@@ -10,7 +10,9 @@ public:
         Path,
         Rectangle,
         Circle,
-        Arc
+        Arc,
+        Line,
+        Polyline
     };
 
 public:
@@ -29,4 +31,19 @@ protected:
     bool mGeometryIsDirty{true};
 };
 
+class LineNode : public GeometryNode
+{
+public:
+    LineNode(const DiscretePoint& location)
+    :    GeometryNode(location)
+    {
+
+    }
+
+    Type getType()
+    {
+        return Type::Line;
+    }
+};
+
 using GeometryNodePtr = std::unique_ptr<GeometryNode>;