• Adobe After Effects

  to.world expression for pointing at a layer

  Posted by Greg Howell on October 18, 2020 at 1:18 am

  Hi,

  Using an expression, I can quite easily have layer A point to layer B, but if layer A is parented to a moving layer (layer C), it no longer works properly. How do I get around this?

  I think its something to do with a to.world expression. I dont know anything about this expression though. Does anyone have any ideas?

  thanks,

  Greg

  Greg Howell replied 5 years, 7 months ago 3 Members · 6 Replies
• 6 Replies

• 

  Walter Soyka

  October 18, 2020 at 2:34 am

  Sure. toWorld is exactly what you want — it translates a point from a layer’s local space to world space.

  This expression should point one layer at another, irrespective of their parenting chains (ancestry?):

  lookAt(thisLayer.toWorld(thisLayer.transform.anchorPoint), thisComp.layer("Target").toWorld(thisComp.layer("Target").transform.anchorPoint));
• 

  Greg Howell

  October 18, 2020 at 2:55 am

  Hi Walter,

  Thanks for your help. Do I paste this in the pointers rotational value?, because it doesn’t seem to work..
• 

  Walter Soyka

  October 18, 2020 at 3:41 am

  It’s for the Orientation property.
• 

  Greg Howell

  October 18, 2020 at 4:02 am

  Do you mean the anchor point property?, because theres only an orientation property in 3d. This is 2d. I pasted it in, but it doesn’t point at the target. See attached.. thanks!

  
• 

  Dan Ebberts

  October 18, 2020 at 10:19 pm

  Probably like this rotation expression (you may have to add or subtract 90, depending on how you have your pointer set up):

  T = thisComp.layer("Target");
  v = T.toComp(T.anchorPoint) - toComp(anchorPoint);
  radiansToDegrees(Math.atan2(v[1],v[0]))
• 

  Greg Howell

  October 18, 2020 at 10:23 pm

  This works perfectly. Thankyou!

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