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.
- The exact engine verified copper per net and dropped a whole net on any
conflict: a 25-pin +3V3 net lost every connection to one bad segment.
Verify and accept per ratsnest connection instead.
- Pad and keepout cells were rounded outward, blocking cells up to half a
step clear of the copper; 62 of the 64 pins of a 0.5 mm pitch LQFP could
not start a route. Block only cells whose centre is inside the clearance
zone, and let a net walk along inside its own pad, which adds no copper.
- Routing was bounded by the outline's bounding box, so tracks cut across
rounded corners. Keep the DSN boundary as a polygon; the grid blocks cells
too close to it (scanline plus per-edge, precomputed for vias) and the
exact and room engines reject copper that is.
- --edge-clearance MM sets copper-to-edge clearance, e.g. KiCad's
min_copper_edge_clearance, which the DSN does not carry. Default 0.
On the TerraHawk rc4 power stage the exact engine now matches the
FreeRouting JAR: same open count, no DRC errors, with a 0.5 mm edge rule.
Ports the data model of the board Item hierarchy (Item base, Pin,
ObstacleArea/ConductionArea, Via, Trace) and BasicBoard (layers, nets,
clearance, bounding box, items with query helpers), then build_board:
the load-bearing integration that constructs a BasicBoard from a parsed
DsnBoard.
build_board maps layers -> LayerStructure, resolution -> transform,
default clearance rule -> ClearanceMatrix, nets -> Nets plus a
(component,pin)->net map, padstacks x placement -> Pin items, and
keepouts -> ObstacleArea items. Rectangle pads become exact IntBoxes,
convex polygon pads exact Simplexes, circle pads their bounding box
(documented approximation); every pad is centred on its pin location so
it contains that location by construction. Trace/Via are router-produced
and lightweight here (an imported unrouted board has none).
Validated on a real KiCad export (kicad_routable.dsn): layer/net/pin
counts match the parsed DSN, every pin's pad shape contains its origin,
every pin reports a valid net, and pin locations lie in the board
bounding box. An oracle-gated test cross-checks that every net the
reference FreeRouting JAR routes exists on the constructed board.