Free script: Prepare Soft Bodies

Prepare Soft Bodies is a small companion script for Newton3, the physics engine for After Effects.

This script prepares a shape layer (or multiple) for a soft body simulation in Newton. It creates many small solids and places them at regular distance along the shape. It also connects the original shape path to the solids using expression.
After running the script, open Newton and add the appropriate joints to create a soft body. When you are back to AE, the original shape will be automatically modified to follow the animation of the small solids.

User Parameters

The script provides a Preferences dialog that allows you to customize the following parameters:

  • distance between 2 consecutive solids
  • size of the solids
  • color of the solids label (fixed color or random color for each path)
  • Bezier tangents method in case of Bezier path (maintain the original tangents or choose adaptative/”auto-bezier” tangents)

Usage Tips

  • When a path is processed, the created solids have the same color so you can select them easily in Newton using the C shortcut.
  • Create a soft body in Newton by connecting the small solids with distance and/or pivot joints.
  • Use the Shift + Click shortcut to create a cycle of joints (i.e., an additional joint is created between the last and the first selected body).
  • In the Joint Properties panel:
    • Turn off Collide Connected
    • For pivot joints, turn on the Enable Limit parameter (you can try to change the limit values)
  • It often helps to increase the Sub-steps parameter in the Global Properties/Solver panel, and the Collision Tolerance too.
  • If your objects are moving too fast, use the Time Divider to slow down the simulation. You can speed it up back in AE.