{
  "id": "wall-street",
  "name": "Wall Street",
  "group": "Inside the amphitheater",
  "center": [
    -112.16635,
    37.6212
  ],
  "width_m": 320,
  "priority": 1,
  "source_ids": [
    "nps-navajo",
    "nps-sunset"
  ],
  "question": "How much of a narrow passage can an aircraft see?",
  "interaction": "returns",
  "theme": "A gap between walls",
  "view_yaw": 1.1,
  "view_pitch": 0.74,
  "schema": 1,
  "kind": "landscape-study",
  "checked_at": "2026-10-02",
  "surface_method": "upper-envelope",
  "geometry_status": "Derived from measured airborne returns; upper-envelope terrain study, not a closed rock scan",
  "coordinate_system": {
    "native_horizontal": "NAD83(2011) / UTM 12N (EPSG:6341)",
    "ept_horizontal": "WGS84 Pseudo-Mercator (EPSG:3857)",
    "export_horizontal": "WGS84 / UTM 12N (EPSG:32612)",
    "vertical": "NAVD88, Geoid12B; source heights retained",
    "units": "metres",
    "axes": "x east, y up from base_m, z south",
    "base_m": 2300,
    "center_utm": [
      397071.2696665937,
      4164427.2992813718
    ],
    "bounds_utm": [
      396911.2696665937,
      4164267.2992813718,
      397231.2696665937,
      4164587.2992813718
    ],
    "bounds_wgs84": [
      -112.16818527973027,
      37.61974020971908,
      -112.16451479025862,
      37.62265976393044
    ],
    "vertical_exaggeration": 1,
    "transform_note": "EPT projection transformed with pyproj; no claim of survey-grade datum alignment. Centimetre export quantization is not source accuracy."
  },
  "statistics": {
    "returns_in_crop": 3699389,
    "density_returns_per_m2": 36.127,
    "ground_returns": 391121,
    "retained_returns": 2108936,
    "vegetation_candidate_returns": 1590453,
    "excluded_noise_or_other": 694,
    "directly_observed_node_fraction": 0.9747880639437015,
    "interpolated_node_fraction": 0.025211936056298425,
    "unsupported_node_fraction": 0.0,
    "isolated_high_cells_repaired": 25,
    "maximum_nearest_fill_m": 3.0,
    "cell_m": 0.625,
    "source_heights_m": [
      2315.050048828125,
      2455.320068359375
    ],
    "surface_heights_m": [
      2315.110107421875,
      2453.22998046875
    ],
    "intensity_display_percentiles": [
      3696.0,
      12912.0
    ],
    "vertical_surfaces": "An upper envelope can join returns across a steep face; it cannot recover undercuts, windows, or unseen interiors.",
    "surface_method": "upper-envelope"
  },
  "levels": [
    {
      "file": "small.glb.gz",
      "bytes": 441952,
      "uncompressed_bytes": 1127292,
      "sha256": "fe24bf65fc072910404c16afc4a0130f1cc0a2b1833624d9a03e1f88fa0c6026",
      "id": "small",
      "vertices": 16641,
      "triangles": 32768,
      "grid_nodes": 129,
      "spacing_m": 2.5,
      "degenerate_triangles": 0,
      "downward_triangles": 0
    },
    {
      "file": "balanced.glb.gz",
      "bytes": 1693870,
      "uncompressed_bytes": 4480904,
      "sha256": "5026680de4e89e8cca1ada597e75fcdcfe2ace3d378fbaa7a010b4a505054fa7",
      "id": "balanced",
      "vertices": 66049,
      "triangles": 131072,
      "grid_nodes": 257,
      "spacing_m": 1.25,
      "degenerate_triangles": 0,
      "downward_triangles": 0
    },
    {
      "file": "detailed.glb.gz",
      "bytes": 6650413,
      "uncompressed_bytes": 17872792,
      "sha256": "cc186c747a9243457f3fb99d7df8b49b91647ee7534ba03570a5d42efa142ae1",
      "id": "detailed",
      "vertices": 263169,
      "triangles": 524288,
      "grid_nodes": 513,
      "spacing_m": 0.625,
      "degenerate_triangles": 0,
      "downward_triangles": 0
    }
  ],
  "returns": {
    "file": "returns.glb.gz",
    "bytes": 1212272,
    "uncompressed_bytes": 2881236,
    "sha256": "7fbd91a67f351cb2b676ab65cd9d1bcfabb09d568b237c77d278eee6217bb0a3",
    "count": 120000,
    "sampling": "fixed seed 20261002, uniform without replacement from valid crop returns"
  },
  "profiles": "profiles.json.gz",
  "camera": {
    "yaw": 1.1,
    "pitch": 0.74,
    "distance_m": 640,
    "target": [
      0,
      72.43994140625,
      0
    ]
  },
  "bounds_local": [
    [
      -160.0,
      15.110107421875,
      -160.0
    ],
    [
      160.0,
      153.22998046875,
      160.0
    ]
  ],
  "source_dataset": {
    "id": "USGS_LPC_UT_Southern_QL1_2018_LAS_2019",
    "acquired": "2018-04-27 / 2018-07-29 project interval",
    "published": "2019-06-03",
    "url": "https://registry.opendata.aws/usgs-lidar/",
    "license": "US Government Public Domain",
    "credit": "Map services and data available from U.S. Geological Survey, National Geospatial Program."
  },
  "processing": {
    "mesh": "Vegetation heuristic applied to an upper envelope. Highest retained return per nearest grid node; nearest interpolation up to 3 m; isolated spikes exceeding all 8 neighbors by 6 m lowered to neighbor maximum. No morphological closing.",
    "vegetation": "Source classes 3/4/5 plus low-intensity multiple echoes and low-intensity raised returns over nearby gentle classified ground are excluded. This is an imperfect heuristic, not a species/rock classifier.",
    "lighting": "Normals and static 12-direction terrain occlusion are derived; material color, studio lighting and display category colors are illustrative.",
    "detail": "Three nested node grids; no-data cells omitted at every LOD; low LOD can omit extra edge triangles to preserve holes."
  },
  "limitations": [
    "Hidden rock surfaces, undercuts and windows are not reconstructed.",
    "A vertical face is an interpolated connection between top-surface samples, not a wall scan.",
    "Vegetation filtering can leave crowns or remove dark rock; inspect the return view.",
    "NAIP is overhead imagery from a different year; it cannot supply photographic detail on vertical faces.",
    "The cut boundary is an editorial crop; there is no modeled geology beneath it.",
    "No route, current condition, erosion rate or collapse forecast is inferred."
  ],
  "posters": {
    "large": "poster.webp",
    "small": "poster-small.webp"
  },
  "quality_status": "accepted_educational_landscape",
  "quality_record": "quality.json",
  "textures": [
    {
      "file": "aerial.webp",
      "width": 534,
      "height": 534,
      "bytes": 103996,
      "sha256": "396a3aad85f35e8ae55a4e836f1eaa892c3eebe9ebef40dee57fd89d84ad3e81",
      "source": "imagery.json",
      "license": "US Government Public Domain, USDA NAIP"
    },
    {
      "file": "aerial-small.webp",
      "width": 512,
      "height": 512,
      "bytes": 75970,
      "sha256": "65a5fb23aada597e578e9eb1a8965ddb57bab74b8e86cd28690ec02284a4d3e4",
      "source": "imagery.json",
      "license": "US Government Public Domain, USDA NAIP"
    }
  ]
}