Keep the source unchanged
The original GeoJSON is retained as a read-only source. Derived tiles, previews and statistics must carry their input hash and build record.
原始 GeoJSON 只读保留；派生瓦片、预览图和统计结果都要记录输入哈希与构建信息。
METHODS / 方法
Evidence before visualisation先核验，再可视化
BeijingData keeps the original source, derived browsing assets and audit record separate.
BeijingData 将原始数据、浏览派生资源和审计记录分开保存。
Check geometry and meaning
Full geometry validity, duplicate IDs, coordinate range, provenance, licence and the meaning of height are checked before a public download is enabled.
公开下载前，必须核查全量几何、重复 ID、坐标范围、来源、许可和 height 的定义。
Load only what is visible
The planned map uses local vector tiles and view-dependent loading. Overview, neighbourhood and single-building scales have different display budgets.
计划采用本地矢量瓦片和按视野加载；全城、片区和单栋尺度使用不同显示预算。
Make every release traceable
Each local build records source, method, output hashes, checks and the exact files changed. Online release remains a separate approval step.
每次本地构建都记录来源、方法、输出哈希、检查结果和变化文件；上线仍需单独授权。
CURRENT LIMITS / 当前限制
What this prototype does not claim
- Height: raw integer values are preserved; no unit, floors or official measured height is claimed.
- Boundary: the six-ring boundary is not included as an authoritative companion file yet.
- Date: the file modification time is not treated as the dataset acquisition date.
- Publication: the source file and derived map tiles are not publicly downloadable in this local prototype.