When analyzing molecular simulations or designing dynamic molecular experiences, it's often helpful to explore how systems behave in reverse. Whether you want to retrace a folding pathway, investigate a transition state return, or simply generate a looping presentation between conformations, reversing a trajectory becomes essential. In SAMSON, this is made possible using the Play reverse path animation.
Why play a path in reverse?
Let’s say you’ve generated a molecular trajectory—using molecular dynamics, a morphing tool, or any simulation that outputs a conformation path—and you want to analyze how it might behave when reversed. Perhaps you want an animation that cycles back and forth between two important configurations. Or maybe you want to synchronize multiple reversed paths for a presentation or video. SAMSON’s Play reverse path effect provides a focused solution.
Getting started
To create a reverse animation in SAMSON, follow these steps:
- Select the path (or multiple paths) you want to animate in reverse. These paths are typically present in your document as “path nodes”—data structures that store trajectories.
- Open the Animation panel within the Animator.
- Double-click on Play reverse path to add the effect. This will create a new animation track between two default keyframes.
- Adjust the keyframes as needed in the timeline to change the duration or timing of the reverse animation.
Customizing the interpolation
If the number of frames in your animation and the number of frames in the path do not match, SAMSON will attempt to smooth the path by interpolating poses. This ensures visual continuity, but you can disable this smoothing if you want a strict reverse of existing frames. Just go to the Inspector panel and uncheck the smoothing option.
Additionally, the Easing Curve settings allow you to fine-tune how parameters such as speed vary across the animation. For example, you may prefer a constant reverse playback speed or apply smooth acceleration and deceleration at the ends for a more polished effect. You can access this setting through the same Inspector panel.
Synchronizing multiple reversed paths
If you select several paths and apply the Play reverse path animation at once, SAMSON will synchronize them. This can be particularly useful in comparative motion studies or illustrating ensemble behaviors such as coordinated folding or binding events.
Practical tip
Want your animation to loop back and forth continuously? Simply combine Play path and Play reverse path effects with carefully timed keyframes. This is a clean technique for visualizations and presentations that require smooth, repeating motion between two states.
To learn more or try this in your project, visit the original documentation here: https://documentation.samson-connect.net/users/latest/animations/play-reverse-path/
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON at https://www.samson-connect.net.