• Adobe After Effects

  Trying to parent “Bulge Center” of Bulge effect to tracking data.

  Posted by Dustin Bowser on September 6, 2011 at 3:21 am

  Hey,

  I’m trying to track a Bulge Effect to a point that I tracked in Mocha. The tracking data was brought into AE and is now sitting as position data on a null.

  I pick whipped the “Bulge Center” property to the “Position” property of my null, and now the Bulge effect is offset. Obviously this has something to do with the different sizes of my footage layer versus the size of the null, and the X,Y position values being different relative to each other, or something like that. I was wondering, how can I offset the Bulge property after I have it attached to the tracker data and moving around?

  I know that I can grab my null, select all of the position keyframes, and move the Null that way, but if possible I’d love to learn the more elegant solution, because I’ve also got other effects and stuff parented to this Null, so having the null “attached” to it’s proper position in the frame is just much easier for keeping everything straight visually. Otherwise later down the line I’m going to wonder what that Null is doing floating off to the left of the screen or whatever.

  I’m sure it’s a really simple expression fix with some Array or something. If anyone has any pointers, I’d really appreciate it. Thanks!

  Roland R. kahlenberg replied 15 years ago 3 Members · 3 Replies
• 3 Replies

• 

  Brian Charles

  September 6, 2011 at 4:25 am

  Not sure what you’re seeing. If you pick whip the Bulge Center to the Null Position there should not be any offset.

  (thisComp.layer(“Trackng Null”).transform.position)

  A Null Object’s anchor point is at 0,0 rather than the center of the Null, is that what you’re referring to?
• 

  Roland R. kahlenberg

  September 6, 2011 at 4:36 am

  Mocha (MochaAE and MochaPro) export 2-point (transformation) data into AE that include Anchor Point data that is identical to the Position data that is exported.

  Always, when exporting 2-point data from Mocha into a Null Layer, remove the Anchor Point keyframes and reset its value. This will set the Null’s value to its default value of 0.

  Now, when you pickwhip the Bulge Center property to the Null’s position, all will be fine and dandy – and Bob will continue to be your uncle and as long as Aunt Annie doesn’t grow a set of cajones, she’ll always be Aunt Annie. 🙂

  HTH
  RoRK

  Intensive AE & Mocha Training in Asia.
• 

  Roland R. kahlenberg

  September 6, 2011 at 5:12 am

  BTW, the following Expression script –
  fromWorld(thisComp.layer(“Null 1”).position)
  applied to the Bulge Center property works without having to mess with the Null’s Anchor Point keyframes.

  HTH
  RoRK

  Intensive AE & Mocha Training in Asia.

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