Creates a box, ellipse, circle, heart, diamond or cloud shape for text backgrounds that auto-resize with the text. Just connect the first parameter to a text layer (or also any other layer) and apply the expression to a path property on a shape layer. This will create a shape that resizes based on the size of the text layer.

The expression offers many options to customize the shape. Boxes can have rounded corners and a minimum and maximum sizes, for example, and offer rotation and shear controls.

Usage

  1. Select the text layer (or other layer whose size should be measured) and click the "connect" button at the "Target Layer" parameter of the iExpression.
  2. Create a new shape with the pen tool and select its path property (or select any other existing shape or mask path that you want to overwrite).
  3. Adjust the other iExpressions parameters however you want (choose the shape type you want, add margins etc)
  4. Apply the iExpression to the path.

Now the path is replaced by a background shape whose size and location follows the target layer.

Auto-Resizing Background Shape iExpression

can be applied to: 
paths
iExpression Bundle: 
Download at aescripts.com

What are iExpressions?

iExpressions are After Effects expressions with an easy to use interface.