diff --git a/libs/canvas/rectangle.cc b/libs/canvas/rectangle.cc
index c79416921f..7c033d447e 100644
--- a/libs/canvas/rectangle.cc
+++ b/libs/canvas/rectangle.cc
@@ -243,5 +243,8 @@ Rectangle::vertical_fraction (double y) const
                 return 0;
         }
 
-        return (i.y - bbox.y0) / bbox.height();
+        /* convert to fit Cairo origin model (origin at upper left)
+         */
+
+        return 1.0 - ((i.y - bbox.y0) / bbox.height());
 }