stack-changing-copies-of so that it can be used in the
following ways. Note that these examples all use
test-bb, but your procedure should work just as well for
any image. Similarly, all of these examples show a stack of height 6,
but your procedure should work for any height that is a positive
integer. All the stacks start with an unmodified image at the top,
and progressively change each copy of the image as you go down the
stack. The way in which the image changes is passed in as a
procedure. The last example, in which this procedure is
invert would have been useful in making checkerboard
quilts.
(stack-changing-copies-of 6 quarter-turn-left test-bb)produces
(stack-changing-copies-of 6 quarter-turn-right test-bb)produces
(stack-changing-copies-of 6 half-turn test-bb)produces
(stack-changing-copies-of 6 mirror-image test-bb)produces
(stack-changing-copies-of 6 invert test-bb)produces