diff --git a/dgl/Geometry.hpp b/dgl/Geometry.hpp
index 580bd318..6ad966e8 100644
--- a/dgl/Geometry.hpp
+++ b/dgl/Geometry.hpp
@@ -458,6 +458,11 @@ public:
     */
     void draw();
 
+   /**
+      Draw lines (outline of this rectangle) using the current OpenGL state.
+    */
+    void drawOutline();
+
     Rectangle<T>& operator=(const Rectangle<T>& rect) noexcept;
     Rectangle<T>& operator*=(const T& m) noexcept;
     Rectangle<T>& operator/=(const T& d) noexcept;
@@ -467,6 +472,8 @@ public:
 private:
     Point<T> fPos;
     Size<T>  fSize;
+
+    void _draw(const bool isOutline);
 };
 
 // -----------------------------------------------------------------------
diff --git a/dgl/src/Geometry.cpp b/dgl/src/Geometry.cpp
index c3954895..600685ac 100644
--- a/dgl/src/Geometry.cpp
+++ b/dgl/src/Geometry.cpp
@@ -621,46 +621,13 @@ bool Rectangle<T>::containsY(const T& y) const noexcept
 template<typename T>
 void Rectangle<T>::draw()
 {
-#if 0
-    typedef void (*glVextex2Func)(T x, T y);
-
-    static bool needsSetup = true;
-    static glVextex2Func glVextex2fn = (glVextex2Func)glVertex2i;
-
-    if (needsSetup)
-    {
-#if 0
-        // TODO
-
-        if (0)
-            glVextex2fn = (glVextex2Func)glVertex2d;
-        else if (0)
-            glVextex2fn = (glVextex2Func)glVertex2f;
-        else if (0)
-            glVextex2fn = (glVextex2Func)glVertex2s;
-#endif
-
-        needsSetup = false;
-    }
-#endif
-
-    glBegin(GL_QUADS);
-
-    {
-        glTexCoord2f(0.0f, 0.0f);
-        glVertex2i(fPos.fX, fPos.fY);
-
-        glTexCoord2f(1.0f, 0.0f);
-        glVertex2i(fPos.fX+fSize.fWidth, fPos.fY);
-
-        glTexCoord2f(1.0f, 1.0f);
-        glVertex2i(fPos.fX+fSize.fWidth, fPos.fY+fSize.fHeight);
-
-        glTexCoord2f(0.0f, 1.0f);
-        glVertex2i(fPos.fX, fPos.fY+fSize.fHeight);
-    }
+    _draw(false);
+}
 
-    glEnd();
+template<typename T>
+void Rectangle<T>::drawOutline()
+{
+    _draw(true);
 }
 
 template<typename T>
@@ -699,6 +666,28 @@ bool Rectangle<T>::operator!=(const Rectangle<T>& rect) const noexcept
     return !operator==(rect);
 }
 
+template<typename T>
+void Rectangle<T>::_draw(const bool isOutline)
+{
+    glBegin(isOutline ? GL_LINE_LOOP : GL_QUADS);
+
+    {
+        glTexCoord2f(0.0f, 0.0f);
+        glVertex2i(fPos.fX, fPos.fY);
+
+        glTexCoord2f(1.0f, 0.0f);
+        glVertex2i(fPos.fX+fSize.fWidth, fPos.fY);
+
+        glTexCoord2f(1.0f, 1.0f);
+        glVertex2i(fPos.fX+fSize.fWidth, fPos.fY+fSize.fHeight);
+
+        glTexCoord2f(0.0f, 1.0f);
+        glVertex2i(fPos.fX, fPos.fY+fSize.fHeight);
+    }
+
+    glEnd();
+}
+
 // -----------------------------------------------------------------------
 // Possible template data types