discontinuedPackage jet_cad_floor_plan has been discontinued and replaced by jet_cad_2d_plan.

preview method

  1. @override
List<(EntityKind, GeometryPayload)> preview(
  1. DraftDocument d,
  2. Handle group,
  3. Grip grip,
  4. Vector2 world,
)

What drag would draw, in world: the pieces a reshape preview paints, computed once per pointer move, never per frame. Empty when there is nothing to show. world is only read during the call.

Implementation

@override
List<(EntityKind, GeometryPayload)> preview(
    DraftDocument d, Handle group, Grip grip, Vector2 world) {
  if (!identical(d, _draggingDocument) || !identical(grip, _draggingGrip)) {
    _dragging = _Label.of(d, group);
    _draggingDocument = d;
    _draggingGrip = grip;
  }
  final s = _dragging;
  if (s == null) return const [];
  final next = s.labelAt(world, aperture());
  if (next == null) return const [];
  final (dx, dy) = next;
  return [
    (
      EntityKind.line,
      linePayload(
          s.poleW, s.toWorld.transformPoint(s.poleL + Vector2(dx, dy))),
    ),
  ];
}