Shape layer overview - After Effects Tutorial

- [Instructor] Shape layers are a crucial component in the After Effects tool set. They are non-destructive by design. Meaning that we can always go back to their initial state to make changes, which ultimately opens up for experimentation. In some ways, it's a lot like a little animatable version of Adobe illustrator, directly inside of After Effects. By grouping these visual building blocks, we can create more complex pieces to use in our projects. And this movie, we'll take a look at what makes shape layers unique. One characteristic is that shape layers are scalable to any size. To show you what I mean, let's come over here to the second composition. And both on the left and right, we have similar looking bits of artwork, except one is made mathematical with vectors on the left, and on the right, we have the artwork created with pixels or a bitmap image. Now, the difference between the two isn't readily obvious, until we take both of these and scale 'em up to, say, 500% here. You can see that on the left, the vector version that's created with shape layers is much sharper than the version that's created on the right with pixels. With a scaling up of 500%, we're telling After Effects to take the existing detail in the bitmap image and create detail where there is none. And that's what's creating this stair-stepping or aliasing effect. It's a quality degradation that doesn't exist with vectors. Now, that's not to say that shape layers are to be used 100% of the time. In fact, both vectors and bitmaps have their pluses and minuses. And it's up to you to decide which best to use in your given situation. It's just important to note here that once we scale past 100%, vectors will always retain their quality. Another thing to note about shape layers is that the same tools used to create them can also be used to create masks. And just like in Photoshop, masks can be used to hide or reveal portions of a layer. Here, we have a shape in the form of a star, and underneath, if we twirl this down, you can see that here's our shape layer, and past that, we have a mask. Both of these were created with the same tools, as found up here. Depending on the context, we can use them to create, either a brand new shape layer or a new mask. We'll get into the specifics on how to build each of these in a later movie. But for now, it's just important to know that these tools can do two different jobs. Another important distinction is that shape layers are considered live. And what I mean by that is that we can go back at any point and change up the initial properties of the shape. So here in our shape layer, let's twirl this down, and under Contents, here's our shape, the Polystar path. And here's all the properties that create this particular star. Right now, it has five points, but I can always go back and change this up to something like 10. And maybe we want to have instead of pointed corners, we want rounded corners. That's one of the major advantages to shape layers is that you can always go back and change it, and you can keyframe this over time to create an animation. Another important characteristic is that we can have one shape per layer. In my timeline here, I have three layers. Inside each of these layers is one shape. So under my Square, for instance, you can see I have a Polystar that is set to four points to create a square. That same Polystar can be used inside of another layer. And instead of four points, we can have one that's created with 12 in order to create a circle. And likewise, we can use three points to create a triangle. Now's probably a good time to clarify some of this terminology I've been using. I've used layer and shape layer. Those two terms can be confusing, since they both used the word layer. In After Effects, a layer can be an audio file, a Photoshop file, a cinema 4D file. There are pretty much any external file that you'll bring to After Effects, versus shape layers which are created internally. Layers are what you'll find in the timeline as number, 1, 2, 3, and so on. Shape layers, on the other hand, live inside of a layer. As we've seen so far, if you want to find a shape layer, twirl down the layer, and you'll find the contents, and inside there, will live the shapes. One good way to look at it is that shapes live inside of layers, layers live inside of compositions. If we hit spacebar to play this animation, you can see that these shapes move, and that's because we have key frames on these layers. To see those key frames, select all three layers, and come over here to Animation, and down here towards the bottom, we have Reveal Properties with Keyframes. In this case, the keyframes are on the layer itself and not the shape layers. And that's something we'll explore further in another movie. That same animation can be recreated using one layer with multiple shapes. So here in this example, I've got one top level layer. And if we twirl this up, and reveal the contents of this one layer, you can see I have a shape layer for my square, here's a shape layer for a circle, and another one for a triangle. Each of these are shapes that live inside of one layer. And if I play this back, you can see that the animation plays somewhat similar to the last one, except now everything lives inside of one top level layer. Here, we saw that shape layers offer enormous flexibility to create elements inside of After Effects, with the added benefit of being able to manipulate those elements in a non-destructive nature.