Rotate a layer to be perpendicular to a path?

[Dan Ebberts]

What’s the expression you’re using to determine the layer’s position?

[Riccardo Sinti]

I’ve got a pre-comp with the path I’m referencing then on the position of the layers that are aligned on the path I have this expression:

PathPercent=effect(“Path Percent”)(“Slider”);
PathLength=comp(“PATH”).duration;
PathCalc=(PathLength*PathPercent)/100;
PathPos = comp(“PATH”).layer(“PATH”).position.valueAtTime(PathCalc);

then on the “Path Percent” “Slider” I have this to control spacing and offset along the path

f = index*thisComp.layer(“OFFSET”).effect(“FACTOR”)(“Slider”);
f + thisComp.layer(“OFFSET”).effect(“OFFSET”)(“Slider”);

So this rig has allowed me to position the people on the perimeter of my logo shape (which is defined by the PATH) and control the space between them with the FACTOR.

Does that make sense?

[Dan Ebberts]

Try this for rotation (not tested, but should be close):

PathPercent=effect(“Path Percent”)(“Slider”);
PathLength=comp(“PATH”).duration;
PathCalc=(PathLength*PathPercent)/100;
v = comp(“PATH”).layer(“PATH”).position.velocityAtTime(PathCalc);
radiansToDegrees(Math.atan2(v[1],v[0]))

Dan

[Riccardo Sinti]

PERFECT!

You are the best!

Thanks so much!