基础表达式AE教程 Skillshare – After Effects Size Expressions: Dynamic Text, Scaling, Images and Debugging着重讲解AE中关于大小的表达式控制，包括sourceRectAtTime表达式、文字或者图片表达式的使用等Working with sizes in expressions can be a bit of a challenge.

In this class I’ll unravel some of the confusing bits about sizing and scaling content.

You’ll learn how to dynamically size elements, a key aspect to building responsive templates.