--- a/Framework/Scene2D/ICompositor.h	Wed Dec 04 19:12:08 2019 +0100
+++ b/Framework/Scene2D/ICompositor.h	Wed Dec 04 20:12:15 2019 +0100
@@ -1,6 +1,7 @@
 #pragma once
 
 #include "Scene2D.h"
+#include "ScenePoint2D.h"
 
 #include <EmbeddedResources.h>
 
@@ -32,5 +33,18 @@
                          unsigned int fontSize,
                          Orthanc::Encoding codepage) = 0;
 #endif
+
+    // Get the center of the given pixel, in canvas coordinates
+    ScenePoint2D GetPixelCenterCoordinates(int x, int y) const
+    {
+      return ScenePoint2D(
+        static_cast<double>(x) + 0.5 - static_cast<double>(GetCanvasWidth()) / 2.0,
+        static_cast<double>(y) + 0.5 - static_cast<double>(GetCanvasHeight()) / 2.0);
+    }
+
+    void FitContent(Scene2D& scene) const
+    {
+      scene.FitContent(GetCanvasWidth(), GetCanvasHeight());
+    }
   };
 }