Ryan Malloy
0bee385e71
Adds route/exact_router.py: routes with the grid track's rip-up/multi-layer/ via topology search in orthogonal mode (axis-aligned segments -> exact IntBox copper), then verifies clearance exactly against a ShapeSearchTree. A net whose copper would come closer than the clearance to any accepted item is dropped, so the emitted geometry is DRC-clean by construction; endpoints stay exactly on pads and vias at real layer transitions. GridRouter gains a non-breaking orthogonal option (4-connected). The pipeline gains an engine= selector: 'grid' (default, unchanged, highest coverage) or 'exact' (DRC-verified). The grid MVP stays the fallback. On the designed boards the exact track routes every net DRC-clean; on the real KiCad board it matches the grid's connectivity (4/4 multi-pin nets) and is DRC-clean where the grid MVP's widened centrelines are not. Deferred: shove, and 45-degree/IntOctagon trace caps. Tests: the exact router's output has no clearance violation (exact IntBox check) on every fixture; endpoints on pads; traces orthogonal; crossing uses a via; and a direct comparison showing the exact track is clean where the grid MVP violates on the real board. Oracle-gated parity for engine='exact'.
freeroute
A native Python PCB autorouter — a Java-free port of the FreeRouting engine.
Why
kicad-mcp currently autoroutes by shelling out to freerouting.jar, which
drags in a JVM dependency. freeroute reimplements the routing engine in
pure Python so the toolchain needs no Java at all.
The contract
The entire integration surface is two Specctra files:
board.dsn ──▶ freeroute ──▶ board.ses
(unrouted) (routed session: traces + vias)
kicad-cli already exports .dsn and imports .ses, so freeroute is a
drop-in replacement for the JAR step — nothing else in the pipeline changes.
Status
Pre-alpha. Under active development. See docs/PORTING_PLAN.md
for the architecture and porting roadmap.
Usage (target)
freeroute board.dsn -o board.ses
Development
uv sync
uv run pytest
uv run ruff check src/ tests/
License
GPL-3.0-or-later, matching the FreeRouting source it is ported from.