I'm new to Graphvis, but I love it. I am mapping my JavaScript code, and so far I have:

digraph G {
  graph [fontsize=24]
  edge [fontsize=24]
  node [fontsize=24]
  ranksep = 1.5
  nodesep = .25
  edge [style="setlinewidth(3)"]
  a[label="$scope.$on(\"playing\")"]
  b[label="$scope.app.adjust"]
  c[label="$scope.app.beforeProceeding"]
  b->c
  a -> playingOrStopped
  HowToShowOp -> image_btn_array
  playingOrStopped -> image_btn_array
}

This gives me a nice diagram in http://magjac.com/graphviz-visual-editor/ however the diagram flows from top to bottom. Does anyone know how to make it flow from left to right instead?