{
 "slug": "tunnel-portal",
 "triangles": 16614,
 "texture_px": 4096,
 "triangles_light": null,
 "texture_px_light": null,
 "files": {
  "glb": {
   "name": "tunnel-portal.glb",
   "bytes": 2970632
  },
  "blend": {
   "name": "tunnel-portal.blend",
   "bytes": 2352111
  },
  "fbx": {
   "name": "tunnel-portal.fbx",
   "bytes": 4590348
  },
  "obj": {
   "name": "tunnel-portal-obj.zip",
   "bytes": 2729689
  },
  "usdz": {
   "name": "tunnel-portal.usdz",
   "bytes": 4332853
  }
 },
 "extras": {
  "license": "CC0-1.0",
  "source": "grab3d.com",
  "dimensions_m": "10.500 x 8.000 x 8.507",
  "triangles": 16614,
  "textures": "PBR 4096px: base color, roughness, metallic, normal (baked)",
  "generator": "Created by grab3d",
  "created": "2026-10-25",
  "real_size": "stone railway tunnel portal, 10.0 m wide facade, 7.8 m high, round arch 4.9 m wide with 6.15 m crown height, 4 m tunnel tube, 8 m of track",
  "notes": "front faces -Y. Clearance fits every vehicle of the Cozy Trains kit: 4.90 m wide, vertical walls up to 3.70 m, crown 5.85 m above rail top (tallest car 5.15 m, raised pantograph 5.0 m, widest car 3.28 m). Ashlar masonry facade with cream voussoirs and keystone, quoins, cornices, pilasters, wing walls, grass on top; the tube darkens inside and is closed at 4 m by the separate dark node 'tunnel-portal_tunnel_shadow' (hide it to build a through tunnel). Track system (Z up): ballast bottom z = 0, rail top 0.30 m; track centre points relative to the model origin (bottom centre of the bounding box): front track end at x +0.000, y -4.000, z +0.000 m heading 180.0 deg; inner track end at x +0.000, y +4.000, z +0.000 m heading 0.0 deg",
  "set": "Cozy Trains & Railway Kit"
 },
 "origin": {
  "method": "procedural",
  "detail": "Built procedurally with Blender scripts. The scripts were written with the help of an AI coding assistant. No generative AI model produced the geometry or textures directly.",
  "ai_content": false,
  "ai_assisted_code": true
 }
}