If you’ve ever spent hours building a complex molecular model only to realize that a few clicks wrecked it — you’re not alone. One of the recurring challenges in molecular modeling is the risk of losing work due to unintended changes. Whether it’s deleting a node, applying the wrong transformation, or selecting the wrong tool, the ability to step back in time — or forward again — is more than a convenience. It’s a necessity.
Thankfully, SAMSON comes with a built-in solution to this: a powerful undo/redo system that tracks your modeling history.
Working with a Dedicated History Per Document
Each time you create or open a document in SAMSON, the system automatically begins tracking your actions — from structural edits to viewing changes — in a separate, document-specific history list. This means you can explore different modeling pathways and safely revert, navigate, or redo steps as needed, without affecting other documents.
To view and interact with your history, use the Interface > History menu or press:
- Ctrl + 3 on Windows or Linux
- Cmd + 3 on Mac
This opens the History View, a panel that visualizes all of your actions as a chronological list.
Undo and Redo: Going Back (and Forth) Safely
Since modeling involves experimentation, it’s essential to have the confidence to try out different ideas. The typical keyboard shortcuts for undo and redo work just as you’d expect:
- Undo: Ctrl + Z (Windows/Linux) or Cmd + Z (Mac)
- Redo: Ctrl + Y (Windows/Linux) or Cmd + Y (Mac)
Alternatively, you can click on individual steps in the History View. This lets you visually scan and jump to a previous state, without needing to undo multiple actions sequentially.
Point-and-Click – Your Time Machine for Molecules
This animated view makes it clear: you can use your document like a timeline, navigating backward to revert a misstep or forward to relive structural forks. This accelerates your modeling workflow, encourages creative trial, and reduces anxiety about making costly mistakes.
One Limitation to Keep in Mind
While most operations in SAMSON are undoable, not all of them are. If you insert a non-undoable command in the middle of a sequence (for example, importing certain extensions or data types), it may prevent earlier actions from being undone. Always test new features in a separate document when possible.
Takeaways
The undo/redo system and History View in SAMSON are more than just convenient. They are essential tools for iterative modeling, safe experimentation, and overall peace of mind.
To learn more, visit the official SAMSON documentation.
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON at https://www.samson-connect.net.