{
  "title": "Walking-distance planting and street furniture",
  "source": "Original procedural geometry and canvas textures authored for Shanghai for You; no third-party plant or lamp models are bundled.",
  "generator": "../street-detail.js and ../seasonal-particles.js",
  "geometry": {
    "trees": "Two reusable irregular mature broadleaf templates, each 16,912 triangles: rooted trunk, connected spreading boughs and 110 attached leaf sprays. Thirty-two smaller interior forks fill four staggered crown levels while retaining a clear lower trunk. This is a 41.9% increase from the prior 11,920-triangle tree template, within the requested 25–50% budget. Autumn morphs the canopy to a broad three-lobed plane-leaf interpretation and uses predominantly bright yellow/gold with a smaller amber variation per leaf. Spring reduces green leaf area while separate cherry blossoms grow along the same twigs. These are distinct seasonal interpretations, not a claim that one botanical species changes into another.",
    "shrubs": "Connected woody stems and opaque shaped leaf sprays, 1,092 triangles per reusable template. No opaque canopy spheres in the active walking scene.",
    "perennials": "Three connected branching stems ending in small leafy tips in Today. Only the short upper flower stalks and petals belong to Bloom, so hidden flowers do not leave bare needles. Reused in circular planters and the seasonal meadow.",
    "pole_lantern": "Original1720triangle model with recessed foot, anchor bolts, collars, tapered pole, framed glazing, roof and internal diffuser;16instances at existing lamp positions.",
    "hanging_lantern": "Original1328triangle model with curved ribs, glazing, metal caps, suspension eye and internal diffuser;9instances.",
    "planters": "Rounded36segment stone vessels with coping, inset48segment soil surfaces and recessed feet. Existing source CC0 concrete normal texture reused.",
    "cherry_blossoms": "2,256 modeled five-petal pink/white flowers per tree: 24 connected blossoms along each of 78 outer flowering twigs and 12 along each of 32 smaller interior twigs. Outward-facing cups give eye-level coverage; no opaque canopy balls or billboard discs. Each flower uses 12 petal triangles plus a four-triangle crossed stalk, totaling 36,096 triangles per tree. All blossom meshes are hidden outside Spring. Flowers grow from their own twig attachment, avoiding transparency sorting holes.",
    "seasonal_drift": "The original baseline retains288 camera-local instanced particles anchored to nearby trees. Spring uses folded pink/ivory petals; Autumn uses broad lobed yellow/golden leaves. Baseline particles fall for roughly10–14seconds, rest20.9–29.7seconds, then42percent can lift and carry1.2–2.9metres in a gust before an opaque screen-door fade. Other particles fade in place. Exact landing anchors and lifted corridors use caller-provided walkable-ground and surface-height callbacks. Autumn behavior is unchanged by the additional Spring gust system.",
    "far_bank_seasons": "Existing mapped/inferred opposite-bank tree geometry and coordinates remain fixed. Distant Spring crowns use pink/ivory, Autumn crowns use yellow/gold, with a restrained seasonal planting-belt grade. These low-detail distant crowns are an authored seasonal interpretation, not a botanical survey.",
    "autumn_leaf_lighting": "Bright golden/amber per-leaf pigment with warm golden transmitted light and a small daylight front-face lift. Removes the earlier green-biased backscatter in Autumn while retaining seasonal geometry, branch structure and triangle counts. This is an inexpensive artistic lighting approximation.",
    "spring_crown_gusts": "A separate Spring-only opaque instanced mesh adds352 reusable slots in two176-petal cohorts. Every22seconds a four-second gust releases one cohort from nearby tree crowns; each petal follows a curved, fluttering6.5–9.2second flight, rests motionless on validated paving for17–21seconds, and fades over2.2seconds. Each gust selects at most four nearest tree crowns within24metres, preserving the wider58metre baseline field. Principal direction follows the avenue, with smooth changes between gusts, while the landing stream is concentrated on validated paving within11metres of the selection-time walker position. A soft rose palette improves contrast against light stone without changing petal dimensions. Slot reuse occurs only after the prior full lifecycle. Maximum combined field640particles; the hard limit remains650if the baseline count is increased. Reduced motion disables these extra gusts and freezes the baseline. No particle objects or typed arrays are created in the animation loop. Natural folded petal shapes are slightly enlarged for walking-distance readability; this is an authored seasonal effect, not a wind simulation."
  },
  "runtime_counts": {
    "revision": 7,
    "trees": 54,
    "shrubs": 125,
    "perennials": 261,
    "lamps": 16,
    "hanging_lanterns": 9,
    "allocated_triangles": 3132472,
    "base_triangles": 1183288,
    "spring_only_blossom_triangles": 1949184,
    "allocated_draw_calls": 39,
    "spring_only_blossom_draw_calls": 6,
    "seasonal_particle_count": 288,
    "seasonal_particle_max_active_draw_calls": 2,
    "seasonal_particle_allocated_triangles": 6144,
    "cherry_flowers_per_tree": 2256,
    "cherry_flowers_total": 121824,
    "flowering_twigs_per_tree": 110,
    "interior_sprays_per_tree": 32,
    "geometry_revision": 6,
    "seasonal_particle_maximum_active_count": 640,
    "spring_gust_capacity": 352,
    "spring_gust_cohort": 176,
    "spring_gust_extra_draw_calls": 1,
    "spring_gust_extra_allocated_triangles": 2112
  },
  "textures": "Original leaf-vein, bark and root-contact textures generated once at startup;720896bytes of uncompressed RGBA source pixels before mipmaps. Foliage uses opaque shaped geometry without alpha cards. Lamp glazing and root contact shade use ordinary transparency.",
  "limits": [
    "Plant forms and lamp design are original interpretations, not surveyed replicas or botanical identification.",
    "Leaf back-light contribution is an inexpensive artistic approximation, not volumetric subsurface scattering.",
    "Shared instancing repeats two tree forms; orientation, height, crown width and color vary.",
    "Existing walking colliders, gift destinations and geographic paths are preserved."
  ],
  "seasonal_references": [
    {
      "url": "https://english.shanghai.gov.cn/en-CityTour/20250310/5d412a2720f84564b457f83178cc6fe7.html",
      "use": "Official Shanghai cherry-blossom season reference; the current promenade planting is an original seasonal interpretation, not a surveyed planting inventory."
    },
    {
      "url": "https://english.shanghai.gov.cn/en-Overview/20241225/ce046a2a1e754fde8c02804d6d66db18.html",
      "use": "Official seasonal guide identifies yellow plane leaves as a Shanghai autumn sight."
    },
    {
      "url": "https://english.shanghai.gov.cn/en-ClosetoNature-travelinshanghai/20251021/088fe91c0410464abf4f9c9baaa8fc9c.html",
      "use": "Official Shanghai autumn foliage story/photo reference for the warm leaf palette."
    }
  ],
  "validation": "Revision 7 keeps revision 6 tree geometry unchanged. Latest gust work passes nineteen focused CPU checks: six gust density/lifecycle/reduced-motion checks, nine seasonal geometry/baseline-lifecycle/bank-color checks, and four real-environment landing/pavilion/reduced-motion checks. Real-scene raycasts validate875 stationary baseline leaves and880 resting gust petals across seven route poses, plus31 explicit pavilion floor/inlay boundary samples. Existing atmosphere and route checks remain separate. GPU visual review is performed by app integration.",
  "landing_surfaces": {
    "walkable_area": "The real north-route containment and walking collider-clearance predicate determine permitted landing anchors and gust corridors.",
    "surface_heights_m": {
      "central_paving": 0,
      "north_path": 0.025,
      "memorial_annulus": 0.033,
      "west_lookout": 0.0355,
      "east_border": 0.0245,
      "east_inset_with_stone_joints": 0.046,
      "pavilion_outer_disk": 0.023,
      "pavilion_inner_disk": 0.035,
      "pavilion_marble": 0.04,
      "pavilion_center_jade": 0.041,
      "pavilion_inlays": 0.044
    },
    "clearance_m": 0.004,
    "selection": "North path and memorial use their actual polygon extents, with raised endpoints combined by maximum height. Pavilion landing height is evaluated against cached actual horizontal floor triangles, preserving polygonal disk edges and the individual inlay footprints rather than a broad clearance plane.",
    "validation": "Real-environment CPU tests raycast authored paving under875 stationary baseline leaves and880 resting gust petals across seven route poses. A31-sample regression checks actual pavilion outer-annulus, polygonal disk boundaries and inlay tops. Positions without nearby trees correctly suppress the field. Reduced motion freezes baseline matrices/fade and disables extra gusts."
  }
}