               x: source.x,
               y: source.y
             }
-            @diagonal({
+            @diagonalProjection({
               source: o,
               target: o
             })

      # Transition links to their new position.
      link.transition()
          .duration(NODE_TRANSITION_DURATION)
          .attr("d", @diagonal)

      # Transition exiting nodes to the parent's new position.
      link.exit().transition()

              x: source.x0,
              y: source.y0
            }
            @diagonalProjection({
              source: o,
              target: o
            })
