When creating scientific presentations or explanatory animations in molecular modeling, it’s often tempting to jump directly to full rotations to highlight structures. However, small periodic motions can be much more effective in some contexts, especially for drawing attention subtly or showcasing molecular flexibility without losing spatial cues. This is where the Rock animation in SAMSON becomes a helpful alternative.
Why not always rotate?
Full rotation can be visually disruptive when presenting crowded molecular environments or large complexes. For smaller groups of atoms or when you want to emphasize a particular region of a molecule, a rotational animation might make it harder for your audience to track what’s happening. The Rock animation, on the other hand, makes the selected atoms move back and forth in a subtle angular motion—much like gently twisting an object in place without taking it for a spin. This keeps the attention centered and the spatial references stable.
How the Rock animation works
When applied, SAMSON computes the centroid of the selected group of particles and rocks them around a vector collinear with the global Z-axis. This produces a subtle wobbling effect that can highlight conformational movement or bring motion to an otherwise static presentation.
You can control how this movement looks over time by adjusting keyframes and using easing curves to interpolate the rocking motion smoothly.
How to set it up
- Select a group of particles you want to animate.
- In the Animation panel found in the Animator, double-click on the Rock animation effect.
- The system adds two keyframes by default. Move them to set the duration and timing of the rocking motion.
- To customize the look and feel of the animation’s flow, adjust the Easing curve.
When to use Rock
- Presenting binding sites with small ligand motions.
- Showing slow-scale, subtle conformational flexibility.
- Adding life to visuals without overwhelming the audience.
- Highlighting portions of a molecule without major repositioning.
In Practice: See it in action
Here is an example of a Rock animation applied to a molecular structure. You can clearly see the back-and-forth movement about the central Z-axis, allowing for a dynamic yet grounded visual:
Example document
If you’re curious to see how this is used in a full presentation context, check out this document on SAMSON Connect:
The Rock effect might seem minor, but for molecular modelers aiming for precise and digestible communication, it’s a valuable resource. Used strategically, it helps your audience stay oriented and focused on the molecular story you’re telling.
Learn more about the Rock animation in the official documentation: https://documentation.samson-connect.net/users/latest/animations/rock/
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