--- a/Framework/Toolbox/ViewportGeometry.cpp	Fri Oct 19 14:44:12 2018 +0200
+++ b/Framework/Toolbox/ViewportGeometry.cpp	Sat Oct 20 18:26:05 2018 +0200
@@ -179,4 +179,22 @@
     zoom_ = zoom;
     ComputeTransform();
   }
+
+
+  Matrix ViewportGeometry::GetMatrix() const
+  {
+    Matrix m(3, 3);
+
+    m(0, 0) = transform_.xx;
+    m(0, 1) = transform_.xy;
+    m(0, 2) = transform_.x0;
+    m(1, 0) = transform_.yx;
+    m(1, 1) = transform_.yy;
+    m(1, 2) = transform_.y0;
+    m(2, 0) = 0;
+    m(2, 1) = 0;
+    m(2, 2) = 1;
+    
+    return m;
+  }
 }