{
  "revision": "bund-soft-grazing-uplights-v4",
  "geometry": "All 27 existing source models retain positions, normals, indices, architectural relief and geographic transform. Only material assignments, metric UVs and pane lighting attributes change.",
  "stone": "Inferred metre-scale ashlar joints, slight block/patina variation and fine roughness/normal response. Carved trim retains continuous grain without extra block joints.",
  "texture_source": {
    "provider": "Poly Haven",
    "url": "https://polyhaven.com/a/smooth_concrete_floor",
    "license": "CC0-1.0",
    "files": [
      "../materials/smooth_concrete_floor_nor_gl_1k.jpg",
      "../materials/smooth_concrete_floor_rough_1k.jpg"
    ],
    "use": "Existing local micro-normal and roughness maps, softly adapted as non-color surface grain. This is not a photograph or measured texture of any Bund facade.",
    "hash_manifest": "../materials/PROVENANCE.json"
  },
  "glass": "Opaque depth-writing dielectric glass with IOR1.52, nonmetallic Fresnel response and a ray-box interior approximation using actual source-pane coordinates. Rooms, curtains, wall panels, depth and occupancy are invented; no surveyed interiors or transparent room geometry are claimed.",
  "night": "Authored warm grazing uplight rows use soft overlapping cones and source-normal incidence to distinguish pilasters, down-facing cornices, stone and dark recesses. Two source-height tiers light the lower facade and upper relief without repeating horizontal bands. Selected actual low central glass panes receive a restrained warm lobby boost. These colors, fixture positions and room occupancy are artistic interpretations, not surveyed lighting or measured photometry.",
  "shadows": "Only four central nearby buildings' nonglass meshes cast into the existing cached directional shadow map; its coverage and resolution remain controlled by the atmosphere module. None of the six new local lights casts shadows or adds a shadow map.",
  "limits": [
    "Texture detail is inferred material characterization, not scanned heritage fabric.",
    "Interior mapping is a view-dependent depth cue, not accessible room geometry.",
    "Night fixture locations and warm color are authored, not a survey of individual heritage buildings.",
    "The bounded real lights omit local shadow maps; occlusion and full indirect illumination are not simulated."
  ],
  "nearby_fixtures": {
    "real_lights": 6,
    "spot_lights": 4,
    "forecourt_fill_lights": 2,
    "new_shadow_maps": 0,
    "placement": "Two spots and one low spill light on each of the two nearby frontages. Positions and aiming points derive from actual loaded world bounds, outside their river-facing -Z edge. The pool is fixed in size; lights fade out before switching buildings, with distance hysteresis. No visible cone geometry is added.",
    "day_behavior": "All additional intensities are zero and the light group is hidden at night=0. Day material parameters and source geometry remain unchanged."
  }
}