Auto Smear Frames for Blender

Last Updated 5-14-2025
Requires Blender 4.4+
Tested in 4.4
Please do not redistribute

2D style smear frames with 3D animation!

As an animator who started with 2D first, making loose and fluid motion is harder to achieve in 3D, and I'm always trying to find ways to bridge the gap.

This smear frame tool automatically places smears for you, but still gives you a lot of control over how they look and when they appear.
It uses the previous 2 frames to create round arc smears, but the accuracy depends on how dense the mesh is.
It works on individual objects as well as entire collections!
It's fast enough that you can view results in real time!

Drop the Blend file into your asset folder or append the asset collection to use these in any project.

3 Modes

Smear - makes a transition from the current frame to the two previous frames, with options for using a texture to add more style to the smear
Multiples - duplicates parts of the mesh and leaves trails of them behind. Can access the 3 previous frames to create longer trails
Smear + Multi - the two previous modes combined
Long Smear (Work in progress, not included) - uses a simulation to blend the current frame with the previous frames, this allows you to add smears to slow moving objects as well as smears that take many frames to resolve

Directions

Applying it to an object

To apply smears to your animation, drag the smear frame tool onto an object from the asset library, or append the smear frame node group from this file

Shading tips

You can use attributes in the shader editor to change how the smears and multiples look.

"smear" attribute can be used to control the smearing part of a mesh
"mask" can be used to control the parts of multiples that would be deleted
"factor" makes a gradient on multiples that becomes stronger the further away it gets from the original mesh

Best practice / limitations

On the timeline, set the playback to play every frame. This is the most accurate way to see the smear frames
Hide the smear modifier while animating and inserting keyframes, otherwise Blender may crash
Use a mesh with a consistent amount of geometry. This tool will not work with objects that add or remove points over time.
Bake before rendering. You can do this from the physics panel. You can also clear the cache here if the smear frame isn't updating properly. I usually turn caching off