Swinging Sign:: Any Tuts or Suggestions?

[Jacob Wessler]

I ran into a similar situation a while back and here is my somewhat “broad-stroke” solution.

I had to create a comp that had two ladybugs carrying a sign and “dropping” it into place so it hung below some lettering.

I used the “beam” effect to generate the cable. While it’s not as nice looking as a chain element, it provided a lot of flexibility.

Using expressions, I connected the beginning point of each of two beam effects to the position of my ladybugs. I then linked the end point of each beam effect to a null object placed at the correct corner of my sign. (One null object parented to the top left corner and another null object parented to the top right corner).

Once that was all set up, I just had to animate the position of the lady bug flying across the screen as well as the position of the sign. Moving the sign back and forth would create the illusion of it lagging behind the ladybugs and then swinging in front of them. Slower movements looked “heavier” while quick movements looked like a “lighter” sign.

It’s a different approach but worked well and didn’t involve a terrible amount of keyframing. The beams just went where they needed to.

Just another idea.

Jacob

[Nick Pitcavage]

I am quite the opposite. I can think of many ways to do this stuff in 3d, but when it comes to AE, I have to re-train my mind to think in a different space. I love the flexibility and ability to maneuver through your workspace in Maya, for example. I with AE was a little easier to move around inside the 3d layers.

Back to the sign project…

I got it to work FLAWLESSLY with tracking… the problem is all the time it takes to track. yikes!

I am resorting to the expression pick whip and running into some problems.

I got the basic pick whip thing, but when I apply the ROTATE of the chord to the POSITION of the sign, the sign doesn’t move at all. (yes, ‘X’ is the correct axis for my sign to move)

I used this:
x = (thisComp.layer(“cables”).transform.zRotation)*-1;

value + [x,0,0]

and I understand the basic expression, but what does this mean?

value + [x,0,0]
and why do you use x = at the very begining?

[Nick Pitcavage]

Jacob, thanks for the insight.

Can you explain the ‘Beam’ effect a little more?
I’ll have to research it a little, sounds like it could’ve worked here.. although, my cables are already mounted and the signs are just rocking in place…

I did get the expression to work. Just some basic oversight on my part. The interesting thing is that I had to use FIVE times as much movement for the sign to stay in the proper place.

so the final script looks like:

x = (thisComp.layer(‘Chord02/simpleChristmasMG.psd’).transform.zRotation)*-5;

value + [x,0,0]

I still am a little unsure what “x =” and “value + [x,0,0]” are exactly.

[David Bogie]

Nick, sorry, I’ve got to refer you to the major expression sites.
Expressions make my brain hurt.

I see you applied a multiplier to get a reasonable swing.

bogiesan

This is my standard sigfile so do not take it personally: “For crying out loud, read the freakin’ manual.”

[Jacob Wessler]

Nick,

I’ll have to wait until later to comment on the beam effect, but I’ll post exactly how I did it when I get home from work.

As for the expression, it’s a way of linking information between layers and properties on your comp.

I can’t tell from your post what property you are applying your expression to, but I’m going to assume it’s the orientation because you are using an array ([x, 0, 0]).

Let’s break down your expression:
x = (thisComp.layer(‘Chord02/simpleChristmasMG.psd’).transform.zRotation)*-5;

value + [x,0,0]

You are defining a variable “x” for later use in your expression. You define this variable as the Z rotation property for the layer ‘Chord02/simplechristmasMG.psd’. This part of the expression will look at the ‘Chord02/simple…’ layer and pick out the Z rotation value at each and every frame and insert it into your expression. You then modify that value with the *-5. This multiplies the value by -5. So, a value of 2 becomes -10. So, your x variable is now defined as -10.

The next line of the expression uses the current value of the property in which your expression is located (I am assuming that you are using orientation because it is a three variable property for rotation. You could also use the axis-specific “Rotation” properties and achieve a similar effect).

So, you take the current value of your property and add your variable x. BUT, since the orientation property has three values – x, y, and z, you need to define WHICH variable you are adding your “x” value to. You could just have easily had “value + [x,x,0]”. This would have added “-10” to BOTH the x and y variables of the orientation.

An orientation value of “[5, 5, 5]” now becomes [-5, 5, 5] because we subtracted 10 from the x value of 5.

Check out Dan Ebbert’s EXCELLENT guide at http://www.motionscript.com. You can also post expression questions in the AE Expressions forum. They are a powerful way to integrate and animate.

Anyway, I’ll post more info on the Beam effect when I get home. Hopefully, this gives you a good place to start.

Jacob

[Jacob Wessler]

Nick,

Okay, the beam effect.

This effect needs to be applied to a solid layer. It really doesn’t matter what color the solid is because you can generate the inside and outside colors of the beam. Add a new solid to your comp and go to “Effect>Generate>Beam.”

Hit F3 to open the Effect Controls panel and you’ll see all the options. If you “alt-click” on the stopwatch, you can add an expression to it. Use the pickwhip to select the position property of the null object you already placed at the correct corner of your sign. (The position property of the null object should be pickwhipped to your sign with adjustments to put it in the top left or right hand corner).

You can adjust the beam thickness to taste. A smaller width will look more like a cable. Can’t do chains with this effect, but it’s quick and dirty.

Keyframe your sign and the ropes will follow along.

Hopefully this makes some sense. If you want a peek at a sample project, I can e-mail you one. Send me a message through my profile.

Good Luck!!!

Jacob