         current = world.get('current')
         "#{current} #{current.get('i')}x#{current.get('j')} -> #{current.get('v_i')}x#{current.get('v_j')}"
     }
-    {
-      _LABEL: "LEFT"
-      row: 1, col: 0
-      name: "L"
-      action: {do: "turn", dir: 1}
-    }
-    {
-      _LABEL: "GO"
-      row: 1, col: 1
-      name: "Go"
-      action: {do: "go", dir: 1}
-    }
-    {
-      _LABEL: "RIGHT"
-      row: 1, col: 2
-      name: "R"
-      action: {do: "turn", dir: -1}
-    }
+    {_LABEL: "left", row: 1, col: 0}
+    {_LABEL: "front", row: 1, col: 1}
+    {_LABEL: "right", row: 1, col: 2}
     {
       row: 2, col: 0
       name: "Step"

    col: 0
    i: (world, args) -> offset(world, 'col')
    j: (world, args) -> offset(world, 'row')
    click: (world, args) ->
      action = world.get('action')
      current = world.get('current')
      #console.log "click #{world} -> #{current} do #{action}"
      current.call(action['do'], action)
  }
  _CHILDREN: [

    half = scale / 2
    "m#{-half},#{-half}  h#{scale} v#{scale} h-#{scale } v#{-scale}"
  signals: {
    left:  {name: "LL", do: "turn", dir: 1}
    right: {name: "RR", do: "turn", dir: -1}
    front: {name: "GO", do: "go", dir: 1}
    back: {name: "REV", do: "go", dir: -1}
    step: {name: "1>", do: "step", n: 1}
