When studying complex biological systems and molecules in motion, scientists often rely on simulations that produce long trajectories. These trajectories help uncover how molecules transition between conformations, interact, and function. However, navigating and presenting these paths effectively can quickly become difficult, especially when you want to highlight a specific part of a simulation or visualize pathways in a controlled way.
This is where the Play reverse path animation in SAMSON really shines. It offers a simple way to play back transformations or trajectories — but crucially, in reverse — without having to recompute anything. This is particularly useful when you want to focus on the return path of a simulation or better understand reversible processes at the molecular level.
Why reverse animations matter
For molecular modelers working with conformational changes, seeing a molecule evolve from state A to B is only part of the story. Often, understanding what happens as it returns to a previous state is just as crucial. Playing animations in reverse can help:
- Inspect reversible conformational changes step-by-step
- Communicate pathways or transitions in presentations more clearly
- Synchronize multiple reverse trajectories
How to use Play Reverse Path in SAMSON
First, select the path(s) you want to animate. In SAMSON, a path node stores a trajectory, like a conformational change or a simulation result. You can select one or more of these paths that you wish to play in reverse. If you select multiple paths, SAMSON synchronizes them automatically for playback consistency.
Next, open the Animation panel in SAMSON’s Animator. Simply double-click on the Play reverse path animation effect to apply it to your selected paths. This creates a new animation between two keyframes where the path will be played backward.
You can move the keyframes as needed to control the timing, e.g., to highlight important parts of the trajectory or synchronize with other animations.
Smoothing and interpolation
When the animation frames don’t perfectly match the number of path frames, SAMSON performs a smoothing operation automatically. This makes transitions look continuous, but you can turn off smoothing in the Inspector if precise frame-to-frame correspondence is required.
Additionally, SAMSON allows you to control how the animation progresses over time using the Easing curve. This is useful if you want to make the animation accelerate, decelerate, or follow a custom interpolation pattern between frames.
Example
Below is an example showing how a path is played in reverse. It helps visualize the motion of a molecule retracing its transformation, highlighting structural changes that are easily overlooked when watching a standard forward playback.
Conclusion
The Play reverse path animation in SAMSON helps researchers and educators present molecular motions interactively and intuitively. Whether you’re reviewing pathway reversibility or preparing a visual demonstration for others, it’s a valuable option to consider during your animation workflow.
To learn more, visit the official documentation page: Play reverse path animation – SAMSON Documentation.
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON at https://www.samson-connect.net.