     uni.change = true
     [ @x, @y ] = location
     @velocity = [ 0, 0 ]
-    @radius ||= 5
+    @radius ?= 5
     @type = Thing
     @others = {}
     uni.addThing @ unless @dontAdd

    candidates = @cell.near @, @radius
    @universe.near @, @radius, 1, {}, candidates
  margins: ->
    m = @marges ||= []
    return m if m.length
    fi = Math.PI * @visualAngle() / 2
    t1 = @angle - fi

      @genes.maxAcceleration[0] = @genes.maxAcceleration[0]()
    else
      @genes.maxAcceleration[0]
  maxSpeed: -> @maxSp ?= @radius * 1.5
  react: ->
    super()
    x = 0
