A memory-safe Rust layout geometry kernel: read/write GDSII and OASIS, do polygon boolean operations, and flatten a cell hierarchy — the substrate the other layout-side tools ride on.

Vyges open EDA tools. Commercial-grade silicon capability, built on open standards and plain file formats — accessible to everyone. vyges-layout is the geometry kernel under LVS extraction, DRC, fill, and the chip viewer.

Docs: docs.vyges.com — this engine's chapter and the cross-engine integration guide. In-repo: docs/engines-integration.md, docs/kernel-notes.md. Integrating and need help? → https://vyges.com/contact.

Everything on the layout side is geometry: LVS device extraction (GDS → devices + nets), DRC (width/spacing), metal fill, and viewing a die — they all need to read GDSII, do boolean operations on shapes, and flatten hierarchy. The open peers (KLayout's database, gdstk) are excellent but C++; vyges-layout is the clean-room, memory-safe Rust kernel, so the Vyges layout tools (and the chip viewer) build on a single, auditable base — and it's the dependency that unblocks vyges-lvs native extraction. It is dependency-light and pure-Rust: the only non-Vyges dependency is miniz_oxide (permissive, pure-Rust DEFLATE) for OASIS CBLOCK decompression — no C toolchain, no GPL.

cargo build --release            # pure-Rust; one small permissive dep (miniz_oxide)

vyges-layout info    block.gds                 # cells, layers, areas, bbox
vyges-layout info    block.gds --json
vyges-layout boolean block.gds --top top --op and --a 67/20 --b 68/20 --out 100/0 -o and.gds
vyges-layout flatten block.gds --top top -o flat.gds
vyges-layout flatten block.gds --top top -o flat.oas   # write OASIS (GDS→OASIS convert)
vyges-layout info    block.oas                          # …and read it back
vyges-layout demo                              # built-in, no files
# `L/D` is layer/datatype; boolean ops: and · or · not (A−B) · xor
# common flags: -o FILE · --json · -q/--quiet · -v/--verbose · -h/--help · -V/--version

A runnable example is generated by cargo run --example gen (committed as examples/two_box.gds): two overlapping metal boxes (for boolean) + two placements of a leaf cell (for flatten).

The kernel is pure geometry: layers, datatypes, and polygons. Nothing in read/write, boolean, or flatten knows or cares whether a shape is a standard cell or an analog device — so vyges-layout applies to digital, analog, and mixed-signal layouts identically.

• Digital: examples/two_box.gds — overlapping metal boxes + a placed leaf cell.
• Analog: examples/analog/ — a non-standard-cell block (a guard ring, a MIM capacitor, and a poly resistor snake). tests/analog.rs proves (a) the GDS write→read round-trips every shape and vertex exactly, and (b) a boolean across two layers is correct: MIM top-plate AND bottom-plate = the exact cap-overlap rectangle, and OR of the two guard-ring halves reunites the full rectilinear ring.

cargo run --example gen_analog   # (re)writes examples/analog/analog.gds
cargo test --test analog         # round-trip + cross-layer boolean on the analog block

The v0 boolean is Manhattan (rectilinear, exact on integer DBU) — that bound is about the geometry (general-angle clipping is the depth pass), not about the design domain; the analog shapes above are rectilinear and handled exactly.

• GDSII read/write — round-trips a library (BOUNDARY/PATH/SREF/AREF/BOX; the GDS real format for units). This replaces the vendored JS GDS parser in the chip viewer.
• OASIS read/write — the compact, modern layout interchange format (typically an order of magnitude smaller than the equivalent GDSII). Reads/writes the RECTANGLE / POLYGON / PLACEMENT subset onto the same in-memory model, so info, boolean, and flatten work on either format — and the tools double as a GDS↔OASIS converter (format picked by file extension: .gds vs .oas/.oasis).
• info — cells, per-cell element counts, layers present, per-layer boundary count and area, in text or JSON.
• boolean — AND / OR / NOT / XOR between two layers via a vertical scanline on rectilinear polygons (rectangles, L-shapes, holey/overlapping Manhattan shapes; integer coordinates → exact), output to a layer.
• flatten — expand SREF/AREF hierarchy into one cell (reflect → mag → rotate → translate, composed; AREF arrays expanded; cycles guarded).
• spatial index (index::RegionIndex) — a uniform-grid index over rectangles for fast region / overlap / spacing-halo queries (the "what's near this shape?" primitive DRC width/spacing, LVS net tracing, and the viewer need to scale beyond O(N²)). Library API; validated against brute force.

Honest bounds (depth reserved). v0 boolean is Manhattan — it handles any rectilinear polygon exactly, but the result is returned as a set of rectangles tiling the region (contour-tracing into merged polygons is depth), and general-angle geometry (a diagonal edge) is bbox-approximated and counted (never silently dropped). General clipping (Vatti) is the depth pass. Arbitrary reference angles round to integer DBU. The OASIS reader is full-coverage — RECTANGLE, POLYGON (with the manhattan implied-closure real writers use), PATH, TRAPEZOID, CTRAPEZOID, CIRCLE, TEXT, PLACEMENT, all repetition forms, properties/name tables, and CBLOCK (DEFLATE) compression — validated against a real third-party corpus: the sky130 standard-cell GDS converted to OASIS by gdstk (both compressed and raw) reads back geometry-identical to the source GDS, and a spread of gdstk trapezoids/triangles match by area. The writer emits the RECTANGLE / POLYGON / PLACEMENT subset (Path stroked to rectangles; Text not written; uncompressed). Remaining ingest gap: the rare CTRAPEZOID 2× isoceles-triangle types (20–23), which error clearly rather than guess. The RegionIndex spatial index provides region/overlap/spacing-halo queries; DRC width/spacing rules on top of it, rectangle sizing, and net tracing for device extraction (the piece vyges-lvs Phase 2 consumes) are reserved.

Apache-2.0, clean-room (no third-party EDA database). The peers (KLayout-db, gdstk) are libraries, not products; this is the Rust one.

GDSII and OASIS read/write (GDS↔OASIS convert), info, Manhattan boolean (and/or/not/xor), hierarchy flatten, and a uniform-grid spatial index for region/overlap/spacing queries; text + JSON; runnable example. Pure std, unit + example tested offline, no subprocess.