|The blinds can be translucent|
Should I make an .lcf a rather than just single object because the bamboo chik material with its alpha transparency is not part of ArchiCAD's default library. Tell me in the comments -- and if there are no comments, I'll assume nobody wants the object.
For future reference (and in case it helps someone else) here's the formula for determining the radius of the rolled up portion of the chiks:
I added a looseness factor to this formula, though, because such blinds are never very tightly rolled.