The graph a V tuft makes
The above-and-below graph of a pile fabric, which has three thread systems and therefore no matrix. The ground ends and picks sit above; the pile end below, with a heavy edge to each pick it passes beneath and a faint one to each it lies over. The criterion is the same one every other draft is decided by.
2 essays call
pile-graph. 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.
Where it is called
Changing this generator changes every one of these figures.
Pile is a third thread system
Velvet, corduroy, plush and carpet all carry threads that are not woven into the ground in the ordinary sense. Two of the three systems make a perfectly good matrix and the third is not in it — so the encoding this whole site rests on has nothing to say about the part of the fabric a hand actually touches.
Velvet is cut apart
Two ground cloths are woven face to face with a pile warp shuttling between them, and while it does the whole thing is one cloth — the criterion says so, and the pile is the only reason it is true. Then a knife runs down the middle and the same criterion says two. The manufacture is the deliberate destruction of cloth integrity.