@chestnutlabs/toolpath-core

Neutral ToolpathIR and capability model for the Chestnut Labs G-code Preview toolpath stack. This is the replacement seam for the whole stack: the parser writes it, renderers and analyzers read it. See docs/design/DD-001.

Design rules

• The canonical IR is plain, transferable data — a small header plus structure-of-arrays typed buffers (not object graphs). Positions are Float32 deltas relative to a Float64 originOffset (floating origin, DD-001 §4.6).
• Unknown is a valid state. Optional/derived data carries a Confidence (known | inferred | approximated | unavailable); missing values are sentinels (NaN, 0), never fabricated data.
• This package depends on nothing — no three, DOM, Vue, or AnyBridge (DD-002 boundary).

Contents (scaffold)

• ir.ts — ToolpathIR, header, segments (SoA), layers/tools/objects, capabilities, MoveKind, FeatureRole, IR_SCHEMA_VERSION.
• builder.ts — ToolpathIRBuilder (accumulate segments → canonical typed-array IR).
• source-index.ts — buildSourceIndex / segmentAtByte (byte offset → segment; live-progress input).
• bounds.ts — extrude-only and travel-inclusive bounds.

npm run build      -w @chestnutlabs/toolpath-core   # tsc -> dist
npm run typecheck  -w @chestnutlabs/toolpath-core
npm test           -w @chestnutlabs/toolpath-core

Status: scaffold (E1, issue #32). The builder accumulates into number arrays and converts to typed arrays in finalize(); E2's worker parser will write directly into growable typed buffers. Package extraction/publish is gated by DD-002 §7 and the release DD (E7/DD-008).