• Adobe After Effects Expressions

  general question about text selectors

  Posted by Mira Etler on October 28, 2008 at 9:15 pm

  I’m trying to add an expression selector to the “amount” prop of a text animator.

  What I’d really like is for someone (probably Dan, but anybody) to clearly explain what exactly the following 3 props are-

  textIndex (in concept I understand this, but I really don’t understand if this is only a getter and if so, what precisely it’s returning)
  textTotal (if this is a character array I do understand, but clarification would be nice)
  selectorValue (totally lost here- what exactly is the point of this, and why can’t it be clearly documented? the help on it is of no use, imho)

  My first indication based on the docs was that the 3rd is that the range selector would be defining this, but 99% of the scripts I’ve seen for this subject delete the range selector, so what’s up with that? Or am I correct in my assumption of it’s functionality?

  Also- How exactly do you get the same functionality of a range selector?

  thanks,
  mira

  Mira Etler replied 17 years, 6 months ago 2 Members · 3 Replies
• 3 Replies

• 

  Mira Etler

  October 28, 2008 at 10:20 pm

  to clarify:

  when i said:
  “My first indication based on the docs was that the 3rd is that the range selector would be defining this, ”

  i meant:
  “My first indication (based on the docs) of the selectorValue was that the range selector would be defining this value,”
• 

  Dan Ebberts

  October 29, 2008 at 2:52 am

  selectorValue represents the value coming into the Expression Selector from the previous Selector. If there is no previous Selector, the value will be 100. If you don’t include selectorValue in your expression, any upstream Selectors (within the same Animator) won’t have any effect on the text (so they might as well not be there).

  At each frame, the expression in an Expression Selector is executed once for each character. This is where textIndex comes into play. When the expression executes, textIndex is the index (starting at one) within the Source Text for the character that is currently being processed by the expression. textIndex is how you make different stuff happen for each character. If you’re using random(), textIndex is a good thing to stick into seedRandom() so that the results are different for each character.

  textTotal is simply the total number of characters in the Source Text, which comes in handy for some calculations.

  It is tricky to get your head wrapped around this stuff.

  Dan
• 

  Mira Etler

  November 10, 2008 at 1:01 am

  thanks dan.
  makes perfect sense, actually.

  m

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