I'm attaching a beam effect to a track. I know one method that works is:
-Create two control nulls
-Parent the nulls to a track null
-On another layer, attach the start and end points of a beam effect to the positions of the control nulls (using an expression to convert the position values toComp space).
However, can you achieve the same result in the following way?
-Create a new solid with two point controls on it. Turn off the solid's visibility.
-Parent the solid to a track null
-Use an expression to attach the start and end points of the beam to the global positions of the point controls
This would give full control of the beam using one layer instead of two separate nulls. But is it even possible to extract the world or comp position of the control points in this way?
on Oct 16, 2017 at 6:03:08 pm Last Edited By Brendon Murphy on Oct 16, 2017 at 6:04:22 pm
Figured this one out - there was a simple error in my expression that kept it from reading properly. Here are the steps, for anyone who is interested:
-Create a solid and turn it off in the timeline. This is the control layer.
-Add control points to the solid
-Parent the solid to your track
-Add the expression in the format below to the beam effect's start and end points
controlPoint = thisComp.layer("name of control layer");
controlPoint.toComp(controlPoint.effect("name of point control")("Point"));