To have Beam’s Starting and Ending Points follow a 3D layer, start by applying the following Expression to the Starting Point parameter –
—
StartTarget = thisComp.layer(“Null 01”);
StartTarget.toComp([0,0,0])
—
Where Null 01 corresponds to the Null representing the start point. Then, analogously, the Expression for the Ending Point parameter
is –
—
EndTarget = thisComp.layer(“Null 01”);
EndTarget.toComp([0,0,0])
—
The trick now is to get the bend. AE’s distort tools will only allow you to anchor one end of the Beam while the other end will drift, depending on your settings. Turbulent Displace seems to have the best ‘control’ (Pin All Locked option) over this but again, it all depends on the how much you distort.
A fool-proof method would be to create a mask shape with two vertices representing the two Nulls you have. You will first have to convert the 3D Null positional values into 2D. Then link each point to its respective Mask’s vertex.
This final step requires a Script – more info here https://provideocoalition.com/index.php/mchristiansen/story/tip_track_a_mask_in_after_effects_with_trackerviz/
Once you’ve got the two mask vertices properly tracked, All you need to do is to convert the default linear mask vertices into bezier mask vertices – this is to convert the straight line into a curve. Of course, apply the Stroke effect to view the line in the Comp Panel.
Kinda long-winded way but it does provide the most control.
HTH
RoRK
Intensive AE & Mocha Training in Asia.