{
  "schemaVersion": 1,
  "date": "2026-10-15",
  "provenance": {
    "creator": "TraceDXF project",
    "license": "CC0-1.0",
    "licenseUrl": "https://creativecommons.org/publicdomain/zero/1.0/",
    "source": "Self-authored deterministic geometry and diagram. References are generated by our script, not AutoCAD/PEDIT/JOIN outputs.",
    "softwareImport": "No AutoCAD or LightBurn execution, import or machining performed."
  },
  "verification": {
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    "method": "Independent reparse of LF ASCII DXF. Coordinates, Z, topology flags and endpoint distances are measured from the reparsed entities. Strict site parser is deliberately not a dependency because its 2D/unit contract is being repaired separately.",
    "precision": "Coordinates are serialized without decimal rounding. 0.04 mm is the authored decimal gap; parsed arithmetic uses JavaScript double precision."
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      "terminalDistanceNote": "Distance between first and last stored vertices; for a closed polyline the closing edge spans this distance, so it is not a missing segment.",
      "closedPolylineCount": 0
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      "bounds2dNote": "Not applicable as a flat XY engineering contour: nonzero Z is preserved in coordinateBounds3dMm, not discarded.",
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      "nonzeroInternalChainGapCount": 0,
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      "terminalDistanceNote": "Distance between first and last stored vertices; for a closed polyline the closing edge spans this distance, so it is not a missing segment.",
      "closedPolylineCount": 0
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  "diagram": {
    "file": "comparison.svg",
    "sha256": "dca61c2fb9b25eee4f957d0b38ee0ffe9f8223f38dd20e7f5bf2a3d1cee44feb",
    "bytes": 1538,
    "captionMapping": {
      "A": "Three separate touching LINE entities, an open chain.",
      "B": "One authored open LWPOLYLINE reference with identical geometry; joining need not close a contour.",
      "C": "One authored closed LWPOLYLINE reference; dashed edge marks the added closing segment, 70 mm long."
    },
    "limitations": "Illustrative geometry only. A/B/C are references, not recorded software before/after results. Colors and dash pattern are explanation styling. No embedded English body copy; article must provide translated caption."
  },
  "limitations": "A known gap does not establish a safe universal fuzz distance or software join success. Open contours can be intentional. Noncoplanar linear objects may produce 3D output in CAD; do not project them silently into XY. No automatic join, close or repair capability is added to TraceDXF."
}