Tracks and vias already on the board were ignored, so other nets could
be routed straight through them (the flight controller's 82 GND
stitching vias and its guard tracks). They are now copper of their net:
other nets keep a pad's distance from them in the grid, the exact check
and the room engine, and they add no connections to route.
freeroute ignored the DSN's planes (KiCad's zones), so it never knew that
pads in a pour are joined by it. On the rc4 power stage those pads sit
inside "keep router off" areas as well, and every connection to them was
dropped without a word.
- Read (plane <net> <shape>) and put each zone on the board as a
ConductionArea of its net. Zones are not obstacles: KiCad refills them
around other nets' copper.
- The grid groups each net's pads and zone pieces that copper already
joins (a pad in a zone, two zones sharing a pad) and routes only between
groups. A connection may end on a zone by a via inside its copper, or by
a track where tracks are allowed.
- wire_keepout now blocks traces only, as KiCad's "no tracks" rule area
does; via_keepout only vias; keepout both, in the grid and in the exact
verifier.
rc4 power stage, exact engine, resolution 2: 2 unconnected, down from 8
(FreeRouting JAR: 12), no DRC errors.
On the TerraHawk rc4 power stage every engine misread the board's rule areas:
- A no-track ring along the board edge arrives as one keyhole polygon, and
keepout polygons were wrapped in a single convex tile, so the ring became
the whole board. Split keepout polygons into convex pieces instead.
- The grid engine rasterized an area by its overall bounding box, which for
that ring is again the whole board; it routed nothing. Rasterize per tile.
- "Keep router off" rule areas arrive as wire_keepout, which the reader did
not know, so tracks ran through them (172 DRC items_not_allowed). Read it
at board and image level. For now it blocks vias too, which is stricter
than KiCad and cannot create a violation.
- place_keepout only restricts part placement; stop treating it as copper.
The oracle now runs the JAR headless; it was opening FreeRouting's GUI on
the desktop for every oracle test.
Ports the read path of FreeRouting's io/specctra/parser package to a
Java-free Python implementation:
- tokenizer: S-expression lexer mirroring SpecctraFileDescription.flex
(comments, quoted strings, the string_quote IGNORE_QUOTE directive,
case-insensitive keywords, and hash-prefixed names)
- sexp: nested S-expression tree builder
- shapes: rect/circle/polygon/path plus area-with-holes scopes
- model: typed dataclasses for layers, padstacks, images, placements,
nets, net classes, rules, keepouts
- reader: recursive-descent scope readers producing a DsnBoard, one
_read_* function per FreeRouting read_scope method
46 pytest cases cover the tokenizer, tree, shapes, and end-to-end
parsing against hand-crafted fixtures modeled on FreeRouting's own
test DSN files. Parses 90 of 91 upstream fixtures (the one failure is
a binary OLE file, not text DSN).
rsp2k