• Adobe After Effects Expressions

  extract a numerical value from another layer…

  Posted by Scott Mccall on January 16, 2009 at 5:17 am

  comp("comp1").layer("master").content("Shape 1").content("Path 1").path

  I have a shape thats being distorted by an expression. I have other shapes that are using the first shape’s path as their own via an expression on their path (see code)

  When I move the vertex points of the master path, the others follow suit.

  I now want to use some expressions to distort the master path, but the expression doesn’t alter the path’s actual vertex values so the other layers don’t follow…

  another example, if i do a simple wiggle expression on a shape’s position, is there a way to extract the shape’s altered position? is there a way to see the wiggle on the graph for instance?

  thanks in advance for any advice 🙂

  Scott Mccall replied 17 years, 6 months ago 2 Members · 5 Replies
• 5 Replies

• 

  Filip Vandueren

  January 16, 2009 at 3:20 pm

  There’s a small curve-like icon between to the “=” and the pick-whip “@” icon if you add an expression. Toggling this will show the post-expression-values in the graph-editor instead of the keyframed values.

  If you do a simple pick whip-expression from one property to another, you’ll always get the post-expression value. So just add a deform to the other paths and pickwhip to the first one.
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  Scott Mccall

  January 17, 2009 at 4:22 am

  thats exactly what i was searching for 🙂 thanks so much!
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  Scott Mccall

  January 17, 2009 at 11:40 am

  ok, i guess that works for parameters such as position, rotation, etc, but not for a path that is being deformed by an animation preset…

  am i out of luck on this one then?
• 

  Filip Vandueren

  January 17, 2009 at 12:07 pm

  Yeah,

  The result of an expression is normally a number,a string, or an array.

  So there are a few things you can keyframe but not script: the colorwheel of colorama, the all in one property of levels, the curves property of the curves effect, and sadly: mask and shape paths.
  Arguably these things could be described by arrays, or a javascript object, but adobe doesn’t support this.
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  Scott Mccall

  January 17, 2009 at 3:37 pm

  I guess what i am referrong to is, for example, if you apply the animation preset “wiggle – gelatin” to a shape, it alters the path of that shape eith expressions through a deform effect… there isn’t a way to get the result of the expressions applied to the shape’s path, I don’t think…

  I am fguring out some workarounds though, but it would have been much easier if I could just extract the resulting deformation. there are lots of deformation/transformation effects that change the shape or position of something, but then you’re left with its pre-effect shape instead of the resulting shape…

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