Module inspect 

Built-tileset inspection: per-zoom directory stats, per-column compressed byte attribution, dedup and compression ratios.

Library port of the packed-stats and point_column_stats stt-core examples. Directory-derived stats (per-zoom, dedup, wire totals) are always computed over EVERY entry — they cost no payload reads. Only the expensive Arrow decode + per-column re-encode is optionally restricted to a deterministic sample (mirroring stt-validate --sample semantics).

Per-column attribution re-encodes each decoded column alone (Arrow IPC + zstd-19) to get a fair compressed-byte share. The per-column sum exceeds the whole-tile size (lost cross-column sharing + per-column IPC framing), so it is used for shares, not absolute wire accounting. The technique is geometry-agnostic: every column — point/line/polygon geometry included — is a plain Arrow array that a single-column RecordBatch can carry.

Structs

ColumnCost

Compressed-byte attribution for one column (merged by name across layers and decoded tiles).

DecodeStats

Decode-pass statistics (the only part of the report that reads payloads).

DedupStats

Entries-vs-blobs dedup accounting over the whole directory.

InspectReport

Full inspection report for a packed tileset.

ZoomStats

Directory statistics for one zoom level.

Functions

format_text

Render the report as compact aligned text.

inspect

Inspect a packed tileset.