3D stroke Attach a light or null object to follow the end point of Stroke (using Red Giant 3D stroke

[electricpalmtrees]

Quite a simple one. using Red Giant 3D stroke i have an elipse. I'd like to add nulls and light to the end point, example so a lens flare will follow the keframes from the 0 to 100 growth.

I've done this before but my mind of wiped.

Anyone help me out? It's an expression i'm sure

thanks

Graham 

[Rick Gerard]

You have a couple of options. First, open Window/Create Nulls From Paths, select the path, then press Trace. This will give you a null that follows a vector path. The null won't follow a path that has been distorted by Trapcode 3D Stroke. If it is possible to have the null follow the 3D distortions available with the plugin, you will need some crazy math expressions to make it work. It's way above my head.

The other option is to select the mask path, set a keyframe so you are sure you have the path, then cut it (or if you want to gamble, select the path and copy), then select a null and Paste. The null will follow the path accurately if the layer's transform properties are all at their default values. Again, you're going to have a very difficult time making the null follow a distorted path. 

Attaching anything else to the null is as easy as Shift + Parent or a Pickwhip expression.

If we knew your design goals, we could give you more detailed suggestions.

[electricpalmtrees]

Hi there,

thank you. I have some orbit ring made in 3D stroke and i'm just wanting to attached a lens flare or particles to the absolute 'end' of the stroke growth (so i'll also maybe using wiggle expressions / sliders for some crazy irratic results) no distortion on the 3D path, its just in 3D space (not flat) and has some XYZ rotations going on.

i think you've answered the question. big thank you 🙂

[Rick Gerard]

You can make the null created by the script 3D, then add another null in the center of the ellipse, and make that one 3D, then parent the null created by the script to the new 3D null.  Name the Parent null "Master."

Then you have to use expressions to tie the transform properties of the new "Master" 3D null to the 3D Stroke 3d Properties. 3D Stroke only rotates in Z, but if you add a 3D camera to the scene, the null keeps the other effects tied to the Trace Null lined up in 3D space.

[electricpalmtrees]

many thanks. the 'create nulls from paths' is a good quick workaround for this job. you have to reset the script if you tweak. I will def take this on board for more explorations of further 3D stroke work. 23 years in motion graphics 🙂 we still keep learning stuff. enjoy the day