{
  "finding": "STD2-030",
  "title": "Mirrored turn family",
  "recorded_result": "All three correspond under those transforms: 289 points / 512 triangles. Partial overlap with selected t4way reaches 134 points / 73 triangles in the recorded test.",
  "checking_steps": [
    "Compare Lturn with X-reflected Rturn and untransformed S90turn2 using unique point and unordered triangle-coordinate sets at five decimals.",
    "This ignores winding, materials and duplicated coordinates. It establishes one geometric family, not three byte-identical files or wholly novel terrain."
  ],
  "limitations": "Partial selected-geometry overlap exists. The family is not three independent removed pieces.",
  "scope": "The recorded result and checking steps summarize preserved excavation research. The source observations below were recomputed for publication review; they do not rerun the earlier geometry fits, UV checks, reference scans or original-x86 experiments.",
  "source_observations": [
    {
      "archive": "edpieces",
      "name": "Lturn.lwo",
      "size": 10400,
      "sha256": "fbca6305970046882744891f16a802d898b72da8a138e862f8750fc30d2ed3d9",
      "identity": "edpieces/Lturn.lwo",
      "mesh": {
        "format": "LWOB",
        "vertices": 289,
        "polygon_records": 512,
        "polygon_vertex_counts": {
          "3": 512
        },
        "fan_triangles_excluding_lines_points": 512,
        "PNTS_sha256": "149b69b2e3f04c6f97d53bd3ab6575eca5ae0e6eb11a81ce8201f5acd40a3fb1",
        "POLS_sha256": "aca2c3cc2776dc56b19a97b84b160d05cab28a957872144243378620ce666557"
      }
    },
    {
      "archive": "edpieces",
      "name": "Rturn.lwo",
      "size": 10400,
      "sha256": "7cc343bcb5661ff75443822c638d4ba9974fbe0b88c8ca1e258dac4db8125e33",
      "identity": "edpieces/Rturn.lwo",
      "mesh": {
        "format": "LWOB",
        "vertices": 289,
        "polygon_records": 512,
        "polygon_vertex_counts": {
          "3": 512
        },
        "fan_triangles_excluding_lines_points": 512,
        "PNTS_sha256": "f67e451c2fc429984fd7b844eec94774d413725ff945fa6c8e3f5a45f87f7b31",
        "POLS_sha256": "797108ade3eee21b3dde02afff3663ee23b1fb44c100f12d65671517e03a04e0"
      }
    },
    {
      "archive": "edpieces",
      "name": "S90turn2.lwo",
      "size": 10400,
      "sha256": "f77d7b912c87012c8d5016052e595866cbc34f011c9f26cd6f9721c7bcc6aca6",
      "identity": "edpieces/S90turn2.lwo",
      "mesh": {
        "format": "LWOB",
        "vertices": 289,
        "polygon_records": 512,
        "polygon_vertex_counts": {
          "3": 512
        },
        "fan_triangles_excluding_lines_points": 512,
        "PNTS_sha256": "149b69b2e3f04c6f97d53bd3ab6575eca5ae0e6eb11a81ce8201f5acd40a3fb1",
        "POLS_sha256": "2d5c381e12fe9eff80578435942ebb6235ff36eec02c4d9d563603231f97ea8b"
      }
    }
  ],
  "source_selection": "Files named in the canonical research note, including related models and controls. This is not a claim that every listed file is unused or a complete dependency closure.",
  "preserved_research_records": [
    {
      "record": "LOOSE_TURN_FAMILY.md",
      "sha256": "a7f59685ba801839bded32489e3a5895d3dde4698b5395c50334c5cb2dd127bc"
    },
    {
      "record": "loose_turn_reference_audit.json",
      "sha256": "81aad10f6f015ea4ad4cd9b981217424d8dd5fde0d8fd715c28633d070f57fe7"
    },
    {
      "record": "loose_turn_selected_geometry.json",
      "sha256": "233c8661ccb76d341e1d0158e659a6e9401dbcfed1e5b5b596c271a64570a485"
    },
    {
      "record": "loose_turn_excavation_comparison.json",
      "sha256": "0e77b6d24217b6cb1a2af57e49567160398453717f247b943785ca4f63f5916f"
    }
  ],
  "record_provenance": "Research-record hashes bind this summary to preserved local records. They do not make those internal records downloadable or replace the original source checks.",
  "fresh_audit": "/evidence/stunt-track-driver-2/source-audit.json",
  "bounded_relationship_audit": "/evidence/stunt-track-driver-2/relationship-audit.json"
}