discontinuedPackage jet_cad_floor_plan has been discontinued and replaced by jet_cad_2d_plan.

trimSeparator function

(Vector2, Vector2)? trimSeparator(Vector2 a, Vector2 b, RoomInputs inputs, { required bool objectSnap, })

The separator a person draws from a to b, in world, as it is stored (spec 10 D20, R-21; Ruling 10-9): the one function the Separator tool and the separator grips call.

With objectSnap (F3), an end inside a wall's uncut band (inputs' closed inputs) moves back along the segment to the first point where the segment, walked from its other end as placed, enters that band: the stored end lies on the face, to rounding, so it joins the face (D5) and the separator does not draw into the wall. An end in open space stays where it was put. An end inside several bands (walls that overlap) stops at the first of their faces the walk meets. When the walk crosses into another band first and passes into the end's band through a joint (a mitre), the trimmed end lies in that other band: it is trimmed again, to where the walk enters that one, and so on while it lies in, or within roomTrace.linear of, a band not yet trimmed to (a mitre's end lies on the edge the two bands share, where the crossing number may count it out of either). Each round moves the end toward the other end along the segment and uses up at least one band, so it stops. Both ends inside one band: null.

Without objectSnap, (a, b) as placed: trimming is object snapping, and an end left inside a band still splits the face correctly.

Either way, a result no longer than roomTrace.linear is null: it would be a degenerate separator (D3).

Implementation

(Vector2, Vector2)? trimSeparator(Vector2 a, Vector2 b, RoomInputs inputs,
    {required bool objectSnap}) {
  var s = a, e = b;
  if (objectSnap) {
    final inA = _bandsHolding(a, inputs);
    final inB = _bandsHolding(b, inputs);
    if (inA.any(inB.contains)) return null;
    if (inB.isNotEmpty) e = _trimmed(a, b, inB, inputs);
    if (inA.isNotEmpty) s = _trimmed(b, a, inA, inputs);
  }
  if (!((e - s).length > roomTrace.linear)) return null;
  return (s, e);
}