Hook up d2d offscreen rendering.

src/geometry/Rectangle.h

@@ -6,10 +6,10 @@
 template<class T>
 class Grid;
 
+namespace ntk{
 class Rectangle : public AbstractGeometricItem
 {
 public:
-
     Rectangle(const Point& bottomLeft, const Point& topRight);
     Rectangle(const Point& bottomLeft, double width, double height);
 
@@ -23,6 +23,11 @@ public:
 
     Rectangle getBounds() const;
 
+    Type getType() const
+    {
+        return AbstractGeometricItem::Type::RECTANGLE;
+    }
+
     void sample(Grid<unsigned char>* grid) const override;
 
 private:
@@ -30,3 +35,5 @@ private:
     double mWidth{0};
     double mHeight{0};
 };
+
+}