Auto orient to camera plane (not camera!)

[Dan Ebberts]

Try this orientation expression:


L = thisComp.layer("Camera 1");
u = fromWorldVec(L.toWorldVec([1,0,0]));
v = fromWorldVec(L.toWorldVec([0,1,0]));
w = normalize(fromWorldVec(L.toWorldVec([0,0,1])));

sinb = clamp(w[0],-1,1);
b = Math.asin(sinb);
cosb = Math.cos(b);
if (Math.abs(cosb) > .0005){
c = -Math.atan2(v[0],u[0]);
a = -Math.atan2(w[1],w[2]);
}else{
a = (sinb < 0 ? -1 : 1)*Math.atan2(u[1],v[1]);
c = 0;
}
[radiansToDegrees(a),radiansToDegrees(b),radiansToDegrees(c)]


Dan

[Tim Drage]

Useful, thanks!

[Jim Darski]

Thanks so much Dan!
This expression work really well. Got sidetracked by several other projects, thus the delay in reply. Anyway, this is a really nice expression. AE should incorporate in the auto orient settings!
J.

[Johannes Eichberger]

Thanks, Dan – really a great expression.

[Nate Mulliken]

Awesome! Dan you are the best.
For those that may have made it this far and need that extra helping hand, it may be good to mention to make sure you zero out all orientation and rotation parameters first. Then lay this expression into the orientation parameter making sure that the name of your comp camera matches the camera name in pasted expression.

Obvious stuff for some but my first question was “where do I put it?”
once I got it in it works great.

Hopefully this is all correct information.

[Jim Darski]

I have no idea why but I getting an error on your expression:

Please help!

[Dan Ebberts]

Hard to say without seeing a project file with the broken expression.

Dan

[Nick Ll]

Thanks for the additional tips Nate! Im new to expressions so that a helped me out. An additional question I have is there any way to use the “Active Camera” rather than the specific camera. Im switching between multiple cameras in my animation but get the sides of objects when i switch, and my futile attempt to put “Active Camera” as the camera name gives me an error. Is there any simple solution if not I could work around it.

[Nate Mulliken]

Nick,
It has been a long time since I have looked into this. I like the idea of using the active camera.
Not sure how Dan’s expression would respond to that.

Is there perhaps a way to use your muli-cam set up as a reference then manually mimic the cuts with new cameras and/or subcomps once you have a lock on your shots?

Then you’d be able to enter the expression on each one?

I realize this is obvious and very clunky not to mention a nightmare to edit if your cuts were to change.

[Nate Mulliken]

Also not sure how you tried to enter active camera in the expression. for example typed out like “activeCamera”

Perhaps look up how to create global variables in After Effects using a controller layer. You may be able to use the expression in some form of controller layer that looks for activeCamera.

-Nate