{
  "description": "沅陵体育场东侧示范街区。roofPolygonPx 来自本地离线卫星拼图 north-satellite.png 的逐栋人工描绘；不含随机补点。屋顶视差及影像年代差异使描绘不能替代测绘足印。楼层/立面为视觉设计估计，逐项可修改。",
  "image": ".scratch/cockpit-shell-panel-layout/verify/artifacts/t35/imagery/north-satellite.png",
  "coordinateReference": "north-source.json provides XYZ z/x0/y0 (TMS reverseY read at stitch time); pixels are full mosaic, not cropped image coordinates",
  "roofs": [
    {"id":"trace-east-01","polygonPx":[[844,262],[923,245],[928,267],[849,284]],"floors":4,"archetype":"apartment"},
    {"id":"trace-east-02","polygonPx":[[839,313],[929,290],[935,313],[845,336]],"floors":5,"archetype":"apartment"},
    {"id":"trace-east-03","polygonPx":[[891,216],[934,203],[940,225],[897,238]],"floors":3,"archetype":"house"},
    {"id":"trace-east-04","polygonPx":[[1002,213],[1075,208],[1077,230],[1004,235]],"floors":5,"archetype":"apartment"},
    {"id":"trace-east-05","polygonPx":[[862,37],[929,23],[934,44],[867,58]],"floors":4,"archetype":"apartment"},
    {"id":"trace-east-06","polygonPx":[[968,409],[1053,388],[1058,408],[973,429]],"floors":4,"archetype":"apartment"},
    {"id":"trace-east-07","polygonPx":[[873,558],[963,535],[968,553],[878,576]],"floors":3,"archetype":"apartment"},
    {"id":"trace-east-08","polygonPx":[[941,816],[1004,814],[1005,834],[942,836]],"floors":4,"archetype":"apartment"},
    {"id":"trace-east-09","polygonPx":[[947,859],[1025,853],[1027,878],[949,884]],"floors":5,"archetype":"apartment"},
    {"id":"trace-east-10","polygonPx":[[989,894],[1146,857],[1153,884],[996,921]],"floors":6,"archetype":"apartment"},
    {"id":"trace-west-01","polygonPx":[[103,187],[134,177],[143,208],[112,218]],"floors":2,"archetype":"house"},
    {"id":"trace-west-02","polygonPx":[[232,380],[274,367],[282,393],[240,406]],"floors":3,"archetype":"house"},
    {"id":"trace-west-03","polygonPx":[[272,443],[382,441],[382,462],[272,464]],"floors":4,"archetype":"apartment"}
  ]
}