Parts now plug INTO the breadboard instead of using it as a junction box:
- Drag magnetism: while dragging, the part's anchor pin snaps to the
nearest hole center (9 px range, 9.6 px grid) so parts land perfectly
aligned, like Wokwi.
- Seating: every pin within 4 px of a hole gets an invisible zero-length
wire (Wire.bb) from pin to hole — the exact model Wokwi persists as
["r1:1","bb1:6t.b","",["$bb"]]. Electrically they are ordinary
wires, so the netlist builder, digital trace and SPICE need zero
changes; they are simply not rendered and not hit-testable. Seating
re-computes on every move/rotation (updateComponent), and moving the
breadboard carries its seated parts along.
- Resistors auto-rotate to vertical when dragged over a breadboard
(their 58.8 px pin span bridges the center trench rows b-f exactly).
- Seat tolerance 4 px: absorbs the worst element pin-spacing residual
(~1.6 px) while staying under half the hole pitch, so a pin is never
ambiguous between holes.
Wokwi interchange fixes that fell out of the diagram.json research:
- import maps the top-level rotate attr onto properties.rotation
(previously every rotated part imported flat) and export emits it
back as rotate instead of leaking it into attrs;
- $bb / empty-color connections import as bb seating wires and export
back as ["$bb"] entries, so parts-on-breadboard projects round-trip;
- wokwi-breadboard-half aliases to the full breadboard (hole names are
a strict superset, so every connection stays valid).
Breadboard elements now export their pure hole grids and import cleanly
without a DOM (node tests); geometry + store seating covered by
breadboard-snap.test.ts and breadboard-seating.test.ts.
f98c3268fa