A preform through its thickness, and whether it is one piece

An orthogonal three-dimensional preform in section, with the binder's path, beside the digraph the integrity criterion consumes: one node per level, an arrow from each level to the one above it, and the binder's own contacts. The warp and weft here are straight and do not interlace at all, so the whole of the connectivity is the binder — and the count of separable pieces is what the criterion returns, unchanged from the weave it was written for.

1 essay calls preform3d. The drawing above is what it returns with no arguments at all; every call below passes it something, because a placement that passes nothing draws whichever member of the family the generator happens to default to rather than the weave its essay argues about.