Page 514 - ProShow Producer Manual

514 18. Modifiers

The basic rule is this: if you try to say that value A is A, ProShow has no idea
what the value for A is, and cannot use it. This works no matter how many
steps you have in the equation. If you try to say that A is B, but B is A, you
still have the same problem. When you create these kinds of loops, you
enter what is called a recursive cycle. ProShow will warn you if you try to use
a recursive value as you set up the modifier. Just be aware of it, and avoid it,
as it can cause completely unpredictable results – or just break.

Note: there is a limitation of modifiers applied to the zoom setting for
layers. The short version of this is “modifying zoom might be tricky.” Zoom
modification won’t always work as expected because of the internal design
of ProShow. For example, adding a zoom of 75% to a zoom setting of 200%
appears as expected in the modifier dialog and graphs, but will result in a
zoom of 150% instead of the expected 275%. In cases like this, it’s because
150% is 75% of 200%.
Although this unexpected result can happen, it usually doesn’t happen, and
most modifications of zoom will work as expected. The reasons for this
limitation are very complex and beyond the scope of this documentation. If
you encounter this kind of unexpected result, be aware that this is a hard
limitation and is not going to be changed in the near future.
Often, a different approach to accomplishing the same modification may be
the only way to work around this issue. This limitation is only present in the
zoom setting and shouldn’t affect the modification of any other settings.
Start experimenting with modifiers and see what else you can come up
with. Remember that if you have an idea for an effect that seems difficult
because it would take entirely too many keyframes, start looking into
modifiers.