Okay, so I'm gonna go to File, Open, what we're gonna do is we're gonna talk about something called nesting compositions, nesting compositions, I'm gonna go to this file, nesting compositions. So, what nesting compositions is about, it's about using entire compositions as a layer in other compositions. So let's say we made a really big animation that's really complex with text animation and shape animation and all these different things, we can take that entire composition and put that like in a TV in another composition. You know, like, if somehow you got footage of somebody watching TV, we take that whole animated composition with all those different layers, put it into one composition and then use it in another composition. So this is a really, really powerful tool when using After Effects. So, we're gonna start by looking at something called precomposing. I have here the superhero scene, and let's say this meteor right here, and there's also fire from the meteor, two different laye...
rs. Now, if I wanted to just duplicate this, let's say I wanted other to make this scene more perilous for our hero, I wanted to put more meteors, like maybe in the background or beneath the clouds, on top of the clouds, just wanted to make a scene like an onslaught, and he's just happened to take the biggest one out right here. So what I can do is I can press Command + D on the Mac or Control + D on the PC for duplicate, and then we can duplicate those. And so now we can move those around and whatnot, and that's fine, but another thing that we can do is precompose these. So we're gonna be looking at a couple different variations of nested compositions, and one of them is precomposing. So with these two layers selected I'm going to go to Layer, Pre-compose, Layer, Pre-compose. Seems like this should be in the Composition menu 'cause it's one of the things that a composition does, but they put it in the Pre-compose, in the Layer menu for some reason. So, I'm gonna choose Pre-compose, and I'm going to call this PRECOMP meteor. I always name my precomps like all caps PRECOMP. It's just so I can instantly recognize that they are precomposed things, and so now this meteor with the fire is now one object, and we could apply other things to this. So one of the things that could apply is glow, which is a very common effect. If you're used to Photoshop, the glow in Photoshop like Outer Glow is a little bit outdated. It was very common decades ago, and it just creates an outer glow around things in the back, and it's kind of hard to do that tastefully these days. It can be done, but it's a little bit more of a challenge to do things tastefully with Outer Glow. But this glow in After Effects, it's a much more real glow. So if you had something like this fire, and you wanted to make it feel like it's alive, you could apply this glow effect. It was the same thing I applied to the light bulb at the beginning of the day. So I can apply this to the meteor and look at that. And we could increase the glow, and now that glow kind of comes around the meteor a little bit. It just feels really organic, it feels like we're getting some, like, heat right around here, you know what I mean, and if I click this effects icon, this is before, after, no different, I mean no comparison how different that is. I mean that's just so much more full of life and energy, and you couldn't get this separately 'cause the magic is wrapping the fire around the meteor. So you kinda have to apply a glow to both. So that's what precomposing does, and not only is it nice for housekeeping because you don't have a bunch of duplicates of a million different layers, but now the meteor and the fire can be treated as a group. At any point I can double click on this precomposed layer and get access to that composition. I could also go back to my project panel, to the PRECOMP meteor, and I could drag this into any composition that I want. I could add more PRECOMP meteors if I want to. But now I could shrink this down, put it in another place in the layer stack, whatever I wanna do, and both of these layers are treated as one. So if you wanted a group of things. One time I made an army on the floor of a castle or on the front yard of the castle, whatever that's called. (laughs) I don't know all of my castle terminology, guys. So a big army and then I precomposed all of the little men, and so then you could duplicate 'em and just make a massive army at once, which is really, really cool. So precomposing is a great thing. Now, another thing we can do with precomposing is that we can do the nested composition thing. So when we have something really complicated like our superhero scene, which also now contains other compositions as layers, we can put that as another layer inside of this scene. So I'm in my library scene, I just drag and drop the superhero scene, and I could now open up the basic transforms for this layer, which layer is really a composition in itself, a whole composition. So I can scale this entire composition at once. I can rotate this entire composition at once. I could fade out the entire composition at once, and that becomes really powerful. So I'm going to scale this back up, and I'm going to call that the end of nesting compositions.