Currently, calling ‘init-auto-scrollbars’ with a virtual canvas size larger 
than a million signals a contract error:

../draw.rkt:231:6: init-auto-scrollbars in canvas%: contract violation
  expected: (integer-in 1 1000000)
  given: 1638400

This arises when scrolling through zoomed-in sounds using ‘rsound’. The limit 
of 1M along with the standard sample rate of 44.1KHz means that you can’t zoom 
in to 1 sample per pixel on sounds longer than 22 seconds.

It seems reasonable to me that there should be some limit, and that I’ll have 
to check for it either way, but in this case, it seems like the 1M limit could 
perhaps be raised without ill effect. Maybe 100M?

Looking at the docs, I see that there’s the notion of a ‘dimension-integer’ 
that’s fairly pervasive. In this case, I can see that changing this might 
impact the scroll-thumb-size computation, and possibly the “page left/page 
right” computation.

John Clements
____________________
  Racket Users list:
  http://lists.racket-lang.org/users

Reply via email to