isOpeningWidth function
Whether w is a width the tools and the panel may give an opening of
kind (spec 08 D6): finite and greater than wallJoin.linear, or than
4 × wallJoin.linear for a gap, whose threshold line is inset from each
jamb (D10). A loaded opening may still hold any width.
Implementation
bool isOpeningWidth(OpeningKind kind, double w) =>
w.isFinite &&
w > (kind == OpeningKind.gap ? 4 * wallJoin.linear : wallJoin.linear);