教程:如何使你的Logo在Adobe After Effects 2015中摆动

欢迎来到本教程，使用Adobe After Effects Creative Cloud 2015为您的徽标添加摆动效果. 摆动效果是一种常见的外观，编辑使用它来增强和添加一些随机性到徽标中, text, or graphics. 我将向您展示两种快速完成这种外观的方法.

First, let’s start with a new After Effects project. 我已经创建了一个合成，其中有一段库存素材作为我的背景(Figure 1, below). 正如你在这篇文章的视频中看到的，在0点30分的地方, this stock footage has a high-paced energy to it, and the wiggle effect will match up perfectly with this. I have a logo that's sitting on top of this background, and right now, the logo doesn't have any kind of movement applied to it.

Figure 1. The After Effects comp we’ll use in this example. Click the image to see it at full size.

Using Expressions

我可以给logo添加摆动效果的第一种方法是使用Expressions. 简而言之，这些都是数学公式，你可以在After Effects中使用它们来动画对象. 现在，它可能听起来令人生畏，但它真的很容易，和After Effects为我们做数学.

在图层上按P键打开logo的位置属性. 然后按“Option”键(Mac OS)或“Alt”键(Windows)，选择“Stopwatch”按钮. 如果操作正确，您将看到位置值将变为红色.

Next, click in the area where it says Transform Position. Here we will enter our expression. 我将输入“wiggle”，然后是公式[4,25]，如图所示 Figure 2 (below). 通过输入这些，我已经告诉After Effects以25像素的速度每秒摆动4次徽标.

Figure 2. Entering the Expression. Click the image to see it at full size.

输入值后，单击框外区域以应用它们. 你可以在1:31的教程视频中看到这个效果的RAM预览. Now, you can adjust the formula as needed. Of course, we could have also done this manually with keyframes, but you can see how much quicker using an Expression was. 有很多复杂的表达方式可供你使用. 只需搜索“After Effects expressions”即可开始探索它们.

s for videos, looping logos, and even events. Give it a try in your next creative project.