Undo moves the event just as the drop did, so it now travels the same
way instead of the chip vanishing off the new day and reappearing on the
old one. The write signals when it starts, the controller puts a copy on
the chip's current seat, and the settle that follows is the drop's own —
glide onto the restored seat, ghost underneath, hand over there.
A week row now publishes what it draws along with where it draws it, so
the controller can find any moved event's seat itself rather than each
row scanning its own lanes.
Jean-Luc Makiola
e13b631e10