When working with molecular simulations, one of the most common goals is to visualize how a molecular system evolves over time. Whether you’re cycling through protein conformations or presenting the movement of atoms along a simulated trajectory, making the motion clear and smooth is essential for communication and understanding.
To address this, SAMSON offers the Play path animation feature — a tool specifically designed to help modelers animate molecular paths between two keyframes. If you’re looking to synchronize or playback one or more trajectories intuitively, this feature may provide just the kind of control you need without manual frame-by-frame editing.
What is the ‘Play path’ Animation?
The Play path animation allows you to animate the transformation along one or more paths, which in SAMSON terminology refers to stored trajectories of molecular structures between conformations or simulation states.
When multiple paths are selected, they are synchronized during playback. This is especially helpful when comparing multiple molecular processes or showing the effect of different parameters across the same structural regions.
How It Helps: A Typical Scenario
Let’s say you’ve simulated the folding of a protein and stored the trajectory in a path node. Previously, showing this trajectory smoothly would require setting up each structural frame manually on your timeline. With Play path, this becomes much more streamlined:
- Select the path or paths you want to animate.
- Go to the Animation panel inside the Animator.
- Double-click Play path — a new animation effect is added.
- Use keyframes to define the start and end of the animation. SAMSON will interpolate frames along the path.
That’s it — now the selected path will be played between your chosen keyframes.
Handling Frame Mismatches and Smoothing
If the number of keyframes in your animation doesn’t match the number of frames in your underlying path, SAMSON automatically smooths the animation. This can be a real time saver for simplifying rough or discrete paths into continuous ones.
Prefer to keep the transitions exact? You can disable the smoothing in the Inspector panel and control the playback precisely as per your original data.
Fine-tuning Animation with Easing Curves
By default, animations in SAMSON use linear interpolation, but sometimes a more natural motion may require acceleration or deceleration. You can edit the Easing curve to interpolate the parameters in a non-linear way. For example, starting the animation slowly and then speeding it up can enhance the visual impact when showing long trajectories.
Simple to Set Up, Easy to Reuse
The beauty of Play path lies in its simplicity. Once set up, it’s easy to return to, adjust, or use across multiple animation sequences. Here’s an illustrative example from the documentation:
Conclusion
If you’re preparing a molecular presentation or trying to better understand structural dynamics, using the Play path animation helps you bring your trajectory data to life in a controlled, repeatable, and efficient way.
Learn more about the ‘Play path’ animation in the SAMSON documentation
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON at https://www.samson-connect.net.