       for t in candidates
         id = t.id
         continue if t.id == tid || seen[id]
-        data = @thingMap[id].others[tid]
+        data = thing.others[id]
         continue if data.tooFar
         if data.distance <= distance
           seen[id] = true

  constructor: ( location, options = {} ) ->
    throw "I need a universe!" unless options.universe
    @setAttributes options
    uni = @universe
    [ @x, @y ] = location
    @velocity = [ 0, 0 ]

    @maxDim = Math.max @width, @height
    @things = []
    @dotCache = {}
    @idBase = 0
    @tick   = 0
    @pause = options.pause || 0 
