Comment 3 for bug 1676814

I guess the question here is how much overlap there should be between the dimension items (permanent "drawing" items that can go on real layers) and ruler overlays that are on the special GAL overlay layer, and aren't really part of the PCB.

Dimension items are specified in the format quite precisely:

  (dimension 68.685752 (width 0.3) (layer F.SilkS)
    (gr_text "2.7042 in" (at 127.262453 64.490833 356.8201699) (layer F.SilkS)
      (effects (font (size 1.5 1.5) (thickness 0.3)))
    )
    (feature1 (pts (xy 160.02 93.98) (xy 161.627338 65.047912)))
    (feature2 (pts (xy 91.44 90.17) (xy 93.047338 61.237912)))
    (crossbar (pts (xy 92.897569 63.933755) (xy 161.477569 67.743755)))
    (arrow1a (pts (xy 161.477569 67.743755) (xy 160.320271 68.266786)))
    (arrow1b (pts (xy 161.477569 67.743755) (xy 160.385328 67.09575)))
    (arrow2a (pts (xy 92.897569 63.933755) (xy 93.98981 64.58176)))
    (arrow2b (pts (xy 92.897569 63.933755) (xy 94.054867 63.410724)))
  )

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