sign hanging from wires

[Ultancourtney]

What you’re asking may be more complicated than what I’ve described:

…but can you not just parent the two wires to the sign and use the top, side, bottom camera views to ensure that the wires intersect whatever they are hanging from in the composition. Then perhaps make a precomp of three layers (wire+wire+sign, and then control click on this comp’s anchor point to move it to the perimeter edge, where the two wires hang from. Then, in 3-D space, rotate the sign to swing over and back. It will then pivot from these wires (ie where the anchor point now lies). Is that what you’re asking?

[Mike Clasby]

Ok, if the wires are rigid, try this.

Overview: Moving Anchor Points, parenting and a few expressions.

I made my 2D Sign from a red Solid (300×200). The wires are two blue solids (I made one and Duplicated it) 4 pixels wide and 300 pixels in height.

Move (drag) the sign into position, and the wires where you want them to start (hanging straight up and down I assumed). With the Pan behind Toll, move the anchor points of the wires to the top of each wire. And move the anchor point of the Sign to the top right corner (or where the Right Wire connects to the sign. When I say left and right I mean as I see the screen.

Add a Null (Layer>New>Null Object) and move it so that it’s anchor point was over the top of the left wire (where the wire’s anchor point was moved to).

Make the Null the parent of the two wire layers (Parent pickwhip (looks like @) from the wire to the null). Make the Right Wire the parent of the Sign.

So the layers look like this:

LAYERS PARENT
1 – Null 1 1. Null 1
2 – Left Wire 1. Null 1
3 – Right Wire 3. Right Wire
4 – Sign

Add these expressions. To the Right Wire’s Rotation, “R” brings up the Rotation Stopwatch, (Alt Click the Rotation Stopwatch and Paste it in):

thisComp.layer(“Left Wire”).rotation

You could have also gotten this by Alt clicking the Right Wire’s Rotation stopwatch then pickwhipping to the Left Wire’s Rotation Stopwatch. The expression just tells the Right Wire to use the left Wire’s Rotation as it’s own.

Add this expression to the Sign’s Rotation:

– thisComp.layer(“Left Wire”).rotation

That just tells the Sign to rotate equally but opposite of the left wire, again created with the pickwhip from Sign’s rotation with the left wire’s rotation, then adding a minus sign in front of the express (to get the opposite rotation).

Now don’t touch the null (lock and shy it if you like).

If you rotate the left wire, the second layer’s rotation, the whole setup will make the sign swing left and right with the wires staying attached as they should.

If you want to find an expression solution ask here:

https://forums.creativecow.net/viewforum/227

[Mike Clasby]

Ooops! I didn’t see you wanted 3D, mine is a 2D solution. You’d better go ask at the Cow Expression Forum.

[Mike Clasby]

Ok, you could use my 2D setup in a limited 3D way. Just add that comp with the my 2D solution to you 3D comp (or precomp the 2D elements). Make that precomp 3D. Now add a camera. When you rotate the Left Wire in the 2D comp, it will work up in your 3D comp, but it will only swing in that 3D Z plane. If you move the anchor point of the precomp in the 3D comp to the level of where the wires attach, you can now rotate it’s X rotation to get it to rotate on that plane. So you can move it on two axis.

For a real 3D solution ask over at the AE Expression Forum, listed in my first post.

[Foureyez]

Hi Yikes 🙂

First of, thanx a lot. As soon as I’m at the office, I’ll give your solution a go!
The project doesn’t have to be in 3D, so your first post will do.
I’ll keep you posted!

[Foureyez]

Just tested your post. Works like a charm! Thanx a lot.