Join George Maestri for an in-depth discussion in this video Rigging replacement animation in After Effects, part of 2D Character Animation.
Once you have the basic hierarchy set up in your After Effects character, you can set up replacement animation. Now, how this is done is by just swapping out the individual mouths that we have. In fact, if I go back to the original Photoshop file, you can see them all laid out. I have all of these individual mouths. What I need to do is be able to swap those in and out to create the illusion of his mouth moving. In other words, we're going to replace this mouth with one of these other ones.
We can automate that to some degree in After Effects. So let me show you how this is done. When I brought in that Photoshop file, you'll notice that we have all of them still in these layers here. So, for example, I've everything that starts with Snout, Snout_Closed, Snout_cons (consonant), Snout_E, Snout_F, Snout_M, all of the different consonants and phonemes that the character will need to speak. Now I need to bring these together into a composition and then I can bring them back into my main character.
So what I've done is I've created a basic composition here, and actually it's blank right now but it's just big enough to hold all of those mouth objects that I have. In fact, I can just take all of them and highlight them, just Shift+Select them and drag them into my Timeline here. Once I have them here I need to make sure that my composition is big enough to hold all of these. Now, I have nine mouths, 1 through9, and I have ten frames.
So that is exactly enough. So the next step is to just animate these so they animate one per frame. So I'm going to go ahead and select all of these layers here, and then I'm going to slide them down so that they're only one to frame long. Then I'm going to go to Animation > Keyframe Assistant > Sequence Layers. When I hit OK, you'll see what happens. It will sequence these layers one per frame, pretty simple.
So I have my animation pretty much in place. But I actually want this to start with the closed mouth. So I'm actually going to go ahead and move this layer up and then just go ahead and swap those, so it starts with this Closed layer. So what you'll notice is that as this moves, that nose is kind of bouncing around little bit. You can see how it moves up and down. So I need to align these to my master frame, which is going to be my closed mouth. So I'm going to go ahead and just slide that layer so that it's all the way across the timeline. You can see how this is all moving against it.
So all I have to do is go one at a time and just select these and then just move them so that that nose lines up. So just go a frame at a time and select the underlying layer, make sure that nose is pretty much registered with that first mouth. Really it's just not going to take all that long.
We've got one more here. Now once I have them aligned, I'm just going to go ahead and slide this one back on the top so that it's back to being one frame and then we'll just do a quick test. You can see how it's pretty much aligned. It's bouncing a little bit, we can tweak this, but for our purposes, it's good enough. So now I have a composition that animates over ten frames, all of them mouths with a blank at the end. So now I'm going to go to my main composition here, I'm going to go to Bear, and I'm going to take this mouth and I'm going to keep it there for just a second while I line up the new mouth here, which is this composition.
I'm going to drag this in and drag it over the original mouth to make sure that I've aligned it. Then I'm just going to go ahead and take this one and I can either turn it off or delete it. I'm just going to go ahead and turn this one off. So now I have the mouths. You can see they're all animating, which is great. The next thing I need to do is be able to control that animation so I can actually do lip sync or something like that. So I'm going to keep this layer selected, then I'm just going to go to Layer > Time and just do Enable Time Remapping.
Now, what this does is it actually sets up a situation where I can actually type in the frame number. And this frame number corresponds to the frame number in this little animation. So when I hit 6, it brings up frame 6, which is in this case the Oh mouth. So if I delete this final keyframe here and just stretch this out, you can see now all I have to do is just type in the number or even use it as a slider and you can just animate whatever mouth you want.
This is a great way to set up this sort of animation. And again, I still need to link this to the head. Now you can use this for mouths, but you can also use it for a lot of other things. In fact, I have a final file that we can open here. I'm just going to go ahead and Open Project, and we're going to open this file called Bear_Rigged. That has pretty much everything set up. So I've got the Mouths set up on this Time Remap, just like we had before, but I also have things like eyelids, so we can actually blink his eyes.
I also have hands. So if you scroll down, for example, to the right hand, you can see how I can time remap his hands so that he can actually make different hand positions. And again, this works for a lot of different things. So keep this in mind as you set up your characters to get them ready to animate.
- Creating character joints that really work
- Building with the Puppet tool in After Effects
- Understanding internal versus external forces in movement
- Reading tracks and assigning mouth shapes for dialogue
- Setting up a scene in both After Effects and Flash
Skill Level Advanced
Q: In the chapter "Creating joints that work,” the author uses a circular point for the joints in the arm animation. Do circles need to be drawn in the joints while tracing the character, or there is another method that can be used?
A: It doesn't absolutely have to be a circle, as shown in the video. However, that method is show because it’s the easiest way to make sure the joints will rotate easily.
It’s a matter of personal preference, so use whatever method will work best for each character.