{
  "experiment": "Same front silhouette, different hidden depth",
  "schema_version": 1,
  "fixture_sha256": "97ca35c30f660618e3c81a9ffae2501bb12ba385404fc67e1e8a7a42f22f73e7",
  "provenance": "Original hand-authored synthetic integer-grid shapes. No AI model, reconstructed asset, third-party asset, or engine output.",
  "scope": "Binary orthographic silhouettes of two synthetic unit-voxel shapes; shared origin and scale; no camera fitting.",
  "not_evaluated": [
    "AI reconstruction quality",
    "perspective images",
    "materials",
    "mesh topology",
    "UVs",
    "game-engine import",
    "model benchmark performance"
  ],
  "empty_union_policy": "IoU = 1 when both masks are empty; IoU = 0 when exactly one is empty.",
  "shapes": [
    {
      "id": "compact",
      "voxel_count": 60
    },
    {
      "id": "deep_cap",
      "voxel_count": 108
    }
  ],
  "views": {
    "front": {
      "ray_parallel_to_axis": "y",
      "image_axes": [
        "x",
        "z"
      ],
      "a_cells": 30,
      "b_cells": 30,
      "intersection_cells": 30,
      "union_cells": 30,
      "a_only_cells": 0,
      "b_only_cells": 0,
      "iou": 1.0,
      "a_mask_cells": [
        [
          1,
          0
        ],
        [
          1,
          1
        ],
        [
          2,
          0
        ],
        [
          2,
          1
        ],
        [
          2,
          7
        ],
        [
          2,
          8
        ],
        [
          3,
          0
        ],
        [
          3,
          1
        ],
        [
          3,
          2
        ],
        [
          3,
          3
        ],
        [
          3,
          4
        ],
        [
          3,
          5
        ],
        [
          3,
          6
        ],
        [
          3,
          7
        ],
        [
          3,
          8
        ],
        [
          4,
          0
        ],
        [
          4,
          1
        ],
        [
          4,
          2
        ],
        [
          4,
          3
        ],
        [
          4,
          4
        ],
        [
          4,
          5
        ],
        [
          4,
          6
        ],
        [
          4,
          7
        ],
        [
          4,
          8
        ],
        [
          5,
          0
        ],
        [
          5,
          1
        ],
        [
          5,
          7
        ],
        [
          5,
          8
        ],
        [
          6,
          0
        ],
        [
          6,
          1
        ]
      ],
      "b_mask_cells": [
        [
          1,
          0
        ],
        [
          1,
          1
        ],
        [
          2,
          0
        ],
        [
          2,
          1
        ],
        [
          2,
          7
        ],
        [
          2,
          8
        ],
        [
          3,
          0
        ],
        [
          3,
          1
        ],
        [
          3,
          2
        ],
        [
          3,
          3
        ],
        [
          3,
          4
        ],
        [
          3,
          5
        ],
        [
          3,
          6
        ],
        [
          3,
          7
        ],
        [
          3,
          8
        ],
        [
          4,
          0
        ],
        [
          4,
          1
        ],
        [
          4,
          2
        ],
        [
          4,
          3
        ],
        [
          4,
          4
        ],
        [
          4,
          5
        ],
        [
          4,
          6
        ],
        [
          4,
          7
        ],
        [
          4,
          8
        ],
        [
          5,
          0
        ],
        [
          5,
          1
        ],
        [
          5,
          7
        ],
        [
          5,
          8
        ],
        [
          6,
          0
        ],
        [
          6,
          1
        ]
      ]
    },
    "side": {
      "ray_parallel_to_axis": "x",
      "image_axes": [
        "y",
        "z"
      ],
      "a_cells": 18,
      "b_cells": 30,
      "intersection_cells": 18,
      "union_cells": 30,
      "a_only_cells": 0,
      "b_only_cells": 12,
      "iou": 0.6,
      "a_mask_cells": [
        [
          0,
          0
        ],
        [
          0,
          1
        ],
        [
          0,
          2
        ],
        [
          0,
          3
        ],
        [
          0,
          4
        ],
        [
          0,
          5
        ],
        [
          0,
          6
        ],
        [
          0,
          7
        ],
        [
          0,
          8
        ],
        [
          1,
          0
        ],
        [
          1,
          1
        ],
        [
          1,
          2
        ],
        [
          1,
          3
        ],
        [
          1,
          4
        ],
        [
          1,
          5
        ],
        [
          1,
          6
        ],
        [
          1,
          7
        ],
        [
          1,
          8
        ]
      ],
      "b_mask_cells": [
        [
          0,
          0
        ],
        [
          0,
          1
        ],
        [
          0,
          2
        ],
        [
          0,
          3
        ],
        [
          0,
          4
        ],
        [
          0,
          5
        ],
        [
          0,
          6
        ],
        [
          0,
          7
        ],
        [
          0,
          8
        ],
        [
          1,
          0
        ],
        [
          1,
          1
        ],
        [
          1,
          2
        ],
        [
          1,
          3
        ],
        [
          1,
          4
        ],
        [
          1,
          5
        ],
        [
          1,
          6
        ],
        [
          1,
          7
        ],
        [
          1,
          8
        ],
        [
          2,
          7
        ],
        [
          2,
          8
        ],
        [
          3,
          7
        ],
        [
          3,
          8
        ],
        [
          4,
          7
        ],
        [
          4,
          8
        ],
        [
          5,
          7
        ],
        [
          5,
          8
        ],
        [
          6,
          7
        ],
        [
          6,
          8
        ],
        [
          7,
          7
        ],
        [
          7,
          8
        ]
      ]
    },
    "top": {
      "ray_parallel_to_axis": "z",
      "image_axes": [
        "x",
        "y"
      ],
      "a_cells": 12,
      "b_cells": 36,
      "intersection_cells": 12,
      "union_cells": 36,
      "a_only_cells": 0,
      "b_only_cells": 24,
      "iou": 0.3333333333333333,
      "a_mask_cells": [
        [
          1,
          0
        ],
        [
          1,
          1
        ],
        [
          2,
          0
        ],
        [
          2,
          1
        ],
        [
          3,
          0
        ],
        [
          3,
          1
        ],
        [
          4,
          0
        ],
        [
          4,
          1
        ],
        [
          5,
          0
        ],
        [
          5,
          1
        ],
        [
          6,
          0
        ],
        [
          6,
          1
        ]
      ],
      "b_mask_cells": [
        [
          1,
          0
        ],
        [
          1,
          1
        ],
        [
          2,
          0
        ],
        [
          2,
          1
        ],
        [
          2,
          2
        ],
        [
          2,
          3
        ],
        [
          2,
          4
        ],
        [
          2,
          5
        ],
        [
          2,
          6
        ],
        [
          2,
          7
        ],
        [
          3,
          0
        ],
        [
          3,
          1
        ],
        [
          3,
          2
        ],
        [
          3,
          3
        ],
        [
          3,
          4
        ],
        [
          3,
          5
        ],
        [
          3,
          6
        ],
        [
          3,
          7
        ],
        [
          4,
          0
        ],
        [
          4,
          1
        ],
        [
          4,
          2
        ],
        [
          4,
          3
        ],
        [
          4,
          4
        ],
        [
          4,
          5
        ],
        [
          4,
          6
        ],
        [
          4,
          7
        ],
        [
          5,
          0
        ],
        [
          5,
          1
        ],
        [
          5,
          2
        ],
        [
          5,
          3
        ],
        [
          5,
          4
        ],
        [
          5,
          5
        ],
        [
          5,
          6
        ],
        [
          5,
          7
        ],
        [
          6,
          0
        ],
        [
          6,
          1
        ]
      ]
    }
  },
  "interpretation": "Perfect agreement in one input silhouette does not uniquely identify hidden 3D shape. This is a constructed counterexample, not a model result."
}