For molecular modelers, accurately representing depth in molecular structures can be a challenge. When analyzing intricate molecular assemblies, it’s easy to lose the sense of spatial relationships, especially when viewing complex 3D models on a 2D screen. Ambient occlusion is here to help solve this issue by enhancing depth perception with realistic shading effects. If you’re striving to create clear and visually compelling molecular visualizations, understanding and leveraging ambient occlusion can make a significant difference.
What is Ambient Occlusion?
Ambient occlusion is a rendering technique that improves depth perception by simulating how light interacts with concave and obscured areas of objects. The idea is simple: deeper, less accessible regions in a molecule are darker because they receive less light. This subtle shading makes it easier to distinguish overlapping structures and spatial arrangements in your molecular models.
In SAMSON, two types of ambient occlusion are available:
- Screen-space ambient occlusion (SSAO): This efficient option provides an approximate simulation of ambient occlusion. It’s quick and suitable for real-time rendering, but it relies on the distance between the molecule and the viewport camera.
- Object-space ambient occlusion: A more realistic but computationally slower method. It’s ideal for producing high-quality images but might not be as responsive for interactive visualization.
Customizing Ambient Occlusion in SAMSON
With SAMSON, you have full control over the ambient occlusion settings. You can toggle it on or off or adjust specific parameters to suit your visualization goals:
- Change the settings in the Rendering > Ambient occlusion section of the Preferences panel.
- Quickly enable or disable ambient occlusion using the Visualization > Options menu for real-time comparisons.
For screen-space ambient occlusion, you can adjust the intensity to find the perfect balance between subtle hints and stronger contrasts that suit your visualization.
Visual Comparisons: The Impact of Ambient Occlusion
To illustrate the benefits of ambient occlusion, consider the Ribbons visual model of a protein (PDB code 1AF6):
Without ambient occlusion:
With screen-space ambient occlusion enabled:
Notice how the second image reveals depth more effectively. The darker recesses in the model create a natural 3D effect, helping you understand its structural composition with ease.
Why Use Ambient Occlusion?
Ambient occlusion is extremely useful when:
- Interpreting complex structures where molecules overlap extensively.
- Creating publication-ready visuals with realistic depth shading.
- Sharing insightful visualizations in presentations or collaborative works.
Even a basic application of screen-space ambient occlusion can significantly enhance clarity and visual aesthetics. Molecular modelers looking to stay productive while delivering high-quality results should consider making ambient occlusion a default part of their toolkit.
Discover more about ambient occlusion and additional rendering effects by visiting the official SAMSON documentation.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use.