# preparing the canvas
update_canvas = () ->
  canvas.width = config.map.width*config.pixelsize+config.map.origin.x
  canvas.height = config.map.height*config.pixelsize+config.map.origin.y
update_canvas()

map_range = (from, to, s) ->
  to[0] + (s-from[0]) * (to[1] - to[0]) / (from[1] - from[0])