Animations are crucial in molecular modeling, not only for presentations but also for understanding complex dynamic processes. Whether you’re illustrating a ligand docking, protein folding, or a simple conformational change, organization and control over your animations are essential. In SAMSON, animation nodes have their own attribute space in the Node Specification Language (NSL), which offers a convenient way to select, hide, or manage animations programmatically.
But what if you’re dealing with dozens of animations? Scrolling through animation nodes manually can become unmanageable. A simple NSL query can help you:
- Quickly find hidden animations
- Select animations by name pattern
- Filter animations by visibility or selection flags
This blog post explores the most useful animation attributes in NSL and how you can use them to gain better control over your molecular dynamics projects.
Why use NSL for Animation Nodes?
Animation nodes often accumulate during exploration and testing. The NSL animation attribute space (short name: an) allows you to filter these systematically. Although animations inherit attributes from general nodes, the NSL queries specific to an are optimized for animation-related use cases.
Key Attributes You Can Use
Here are some animation attributes you can immediately start using in your NSL queries:
an.h – Hidden
This boolean attribute tells you whether an animation is hidden. Use
an.h to select hidden animations, and not an.h to show only visible ones.
an.v – Visible
Similar to an.h, but this time focusing directly on visibility status. It can be handy in scripts or custom selection logic.
an.n – Name
You can search for specific animations using textual patterns. For instance:
|
1 |
an.n "Ligand*" |
This retrieves animation nodes whose names start with “Ligand”—great when animations follow naming conventions.
an.selected – Selected
Indicates whether the animation is currently selected in the GUI. You can also use not an.selected to find unselected animations.
an.sf – Selection Flag
This boolean flag controls whether an animation can be selected. If you want to disable selection for animations intended to remain static, use:
|
1 |
an.sf false |
an.vf – Visibility Flag
Controls whether visibility can be toggled for an animation. Use an.vf false to lock the visibility of certain animations during cleanup or analysis.
Example Use Case: Cleaning Up Your Animation Workspace
You’ve just completed a simulation session and created 30+ animation nodes, but you only want to keep visible and selected ones.
Here’s a query that gives you exactly that:
|
1 |
an.v and an.selected |
Now, combine that with filters for name patterns, and you’ll have a workspace that reflects your current focus, without unnecessary clutter.
How Are These Attributes Different?
While most attributes are inherited from the node space, an.selected notably lacks a short alias like s. This means you must spell it out as an.selected. It’s a reminder that although attributes look familiar, their behavior may subtly differ in specialized contexts like animations.
To learn more about working with animation attributes and other tools in NSL, visit the official documentation page.
SAMSON and all SAMSON Extensions are free for non-commercial use. Download SAMSON at https://www.samson-connect.net.