When you’re crafting a molecular animation—perhaps to highlight a binding site, depict a conformational change, or simply help your peers better understand motion in a protein—it’s not always about rotating or dragging atoms. Sometimes, you just want a subtle, naturalistic movement. That’s where the Rock animation in SAMSON comes in.
Many molecular modelers struggle to strike a balance between clarity and aesthetics when creating animations. A static model can feel lifeless, but an overdone rotation might distract from the point. The Rock animation solves this by gently moving a group of particles back and forth around their centroid in a way that mimics natural oscillation—like a biological molecule breathing, swaying, or responding to energy changes. It’s particularly useful in presentations or teaching, where dynamic visualization can make abstract molecular events more accessible to both scientists and students.
How it works
The Rock animation works on a selected group of particles and makes them oscillate around an axis that’s collinear with the Z-axis and goes through their geometric center. This motion is not arbitrary: it introduces a centered, balanced effect that draws attention without being intense or overwhelming.
Adding the rock effect to your animation
- Select the group of atoms or particles you want to animate. You can refer to SAMSON’s selection tools described here.
- Go to the Animation panel in the Animator workspace.
- Double-click the Rock animation effect. It will be applied to your selected particle group.
- Adjust the keyframes to control the timing and duration of the rocking motion. You can do this by dragging the keyframes in the timeline.
For finer control over the movement, you can change how the interpolation occurs between frames by modifying the easing curve. This allows you to dictate whether the motion starts slow and ends fast—or vice versa—adding personality to your animation.
When and why to use it
This subtle oscillation is perfect for emphasizing a group of atoms without rotating them out of view. It’s useful in situations such as:
- Highlighting flexible domains in a protein
- Showing small conformational shifts between different structural states
- Giving motion to a frame during a presentation to keep viewers’ focus
Unlike Rotate or Move animations, Rock gives a sense of energy without displacing the model too much. For that reason, it’s especially valuable in demonstration materials and teaching.
Want to see it in action?
Here’s an example from a presentation document available on SAMSON Connect: 2BRD – Rock animation.
To explore this animation feature further and learn the full steps, visit the official documentation page: https://documentation.samson-connect.net/users/latest/animations/rock/.
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON at www.samson-connect.net.