Join Dermot O' Connor for an in-depth discussion in this video Shape tweening hair, part of Flash Professional: Animation Tips and Tricks.
So this is a demonstration of a technique that I kind of stumbled across by accident, a few years ago. You tend to assume that some shapes are just too complicated to shape tween. And out of pure boredom or desperation, I tried shape tweening a really complicated shape, like this hair, for example, and to give an idea about the context of it. It's just a very simple, very rough hair outline; there is a quick sketch of the character beneath, and there's the hair. So let's -- actually we probably see it better if we look at it in outline mode. Let's play it. And there are no shape hints here; it's all happening without any hinting, which is really amazing.
And the thing that made it work was the use of the Envelope tool. So let me quickly demonstrate this. I will make a new layer. I am just going to copy the existing start position up here, and we will just get rid of the tweens for now. So here we have the outline. Now, if you want to follow along and you don't have the Exercise files, what I would do would be to just pick the Rectangle tool, pick any colors you like, doesn't really matter. Hold down the Alt key, and just make some complex shape that's got a lot of points, and lines, and geometry. And then once you're happy with the fact that it's probably pretty detailed then you can start playing along with this. And you know, obviously put some curves on it to make it feel a little more natural.
So anyway, that's what I would do if you have to generate the assets yourself. So once you have got your regular shape, let's make some keyframes, and I will show you exactly how I did the original. So let's click on Frame 10, and I am going to activate Free Transform, and down here we have the Envelope. So click on that, and you see immediately that the hair has suddenly got a nice little bounding box around it. And as you pull these points, you have access to these little spline handles, and you can just click and drag them. So I am just pulling them into various positions, and now we've made a nice transition.
If I hit Create Shape Tween, that's a smooth motion between that, and we simply repeat the process on the next key. Just do a different one this time. Now this isn't a magic bullet. At some point it's going to break, and it may break on you with a different shape, or a different direction if you pull this too far. If you're careful with it you can always go back to your original position, and work it back until you can get it working again.
So that's basically it; that's the process I have been using. This is very handy, as you can imagine, for things like clouds or natural effects and things. The big problem that you're seeing right here is that it is one continuous mass. So obviously, we would like these hair filaments to move at different speeds, and different directions, and overlapping timings, and so on. But still in all, this is a little more power than you would have if you were simply using motion tweening to stretch and squash the object.
So let me just play that again. And we have the original layer too. So that's a very useful tool. I would warn you of one thing that they seem to have changed in the new version. In the older versions you could select more than one layer, like this, and you could then use the Envelope tool. In the new version they've disabled that. So unfortunately, we can only apply this to one layer now. And that is a bit of problem. I don't know why, but people who have an old version lying around, or are wondering whether they should upgrade, might want to bear that in mind if this is important to them. But we can work around all these problems of course.
And in the next section, I'll show you how we can break apart the hair, and the different layers, and extract even more performance from this technique.
- Overlapping and animating colors
- Creating lens flares
- Animating hair with shape tweens
- Animating an explosion
- Animating smoke with particles
- Animating a scream
- Using Virtual Cam
- Lighting a 3D shot
- Animating cross dissolves