• Adobe After Effects Expressions

  If and Wait

  Posted by David Gray on April 16, 2009 at 1:01 pm

  Hey Guys,

  I’m new to expressions so don’t really know what i’m doing wrong or right. :p

  Basically I’m trying to get a layers opacity to go to 100 3 frames after another layers opacity has reached 100.

  Is there even a wait command?

  Text1 is the layer than i want to trigger ther
  opacity change in text2 in this example.

  I’m thinking it would be something along the lines of:

  if (thisComp.layer(“Text1”)opacity) =100) {wait = 3 then opacity =100}

  else

  {opacity = 100}

  Any and all help greatly appreciated.

  Cheers
  Dave G

  David Gray replied 17 years, 4 months ago 3 Members · 10 Replies
• 10 Replies

• 

  Dan Ebberts

  April 16, 2009 at 1:16 pm

  Would a 3-frame delay work?

  delay = 3;
  thisComp.layer(“Text1”).opacity.valueAtTime(time – framesToTime(delay))

  Dan
• 

  David Gray

  April 16, 2009 at 1:40 pm

  Hey Dan,

  Thanks for the help I think it should. I’m having some problems though probably just due to my lack of knowledge.

  At the moment the expression is(in texts 2 opacity):
  delay = 3;
  if (thisComp.layer(“Text1”)opacity.valueAtTIME)(time – framesToTime(delay) then {100} else {0};

  I’m getting the following error don’t think it is even getting to the delay.

  After Effects warning :Expected: )
  Expression disabled.
  Error occured at line 2.
  Comp: Comp 1
  Layer: 1 (‘text 2’)
  property: opacity

  So I guess I’m missing an ) from somewhere not sure where though.

  Cheers
  Dave
• 

  Dan Ebberts

  April 16, 2009 at 1:55 pm

  Just copy and paste this exactly (don’t add the else stuff):

  delay = 3;
  thisComp.layer(“Text1”).opacity.valueAtTime(time – framesToTime(delay))

  Dan
• 

  David Gray

  April 16, 2009 at 2:07 pm

  Oops yep is working now!

  Only Problem now (not a major one) is it fades in. Would there perhaps be a way for it to place another key frame on the second frame with opacity 0 and then jump up to 100?

  Thanks a lot so far though!

  Cheers
  Dave
• 

  David Gray

  April 16, 2009 at 2:09 pm

  Actually don’t worry it happens so fast you can’t really tell :p

  Though if there is a solution you can think of is always interesting to hear/learn

  Cheers
  Dave
• 

  Dan Ebberts

  April 16, 2009 at 2:26 pm

  This should work:

  delay = 3;
  opat = thisComp.layer(“Text1”).opacity.valueAtTime(time – framesToTime(delay));
  if (opat < 100) 0 else 100 Dan
• 

  David Gray

  April 16, 2009 at 9:46 pm

  Cheers Dan!

  You’ve been a great help.
• 

  David Gray

  April 17, 2009 at 1:20 pm

  Hey Dan,

  Back again for your excellent help :p

  I’m thinking that it would be possible to optimise this expression for my task my having it insert the name of the layer below automaticly. I had a quick google but no avail.

  So the code in layman’s terms
  delay = 3;
  thisComp.layer(“LAYERBELOW”).opacity.valueAtTime(time – framesToTime(delay))
• 

  Curious Turtle

  April 17, 2009 at 2:03 pm

  To look at the layer below you can use:

  delay = 3;
layerBelow = thisLayer.index+1;
thisComp.layer( layerBelow).opacity.valueAtTime(time - framesToTime(delay))

  Cheers,
  Ben

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• 

  David Gray

  April 19, 2009 at 1:14 am

  Thanks a lot mate! Working perfectly.

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