A molecular model can contain all the right structural information and still be hard to read. At a glance, nearby and distant regions may blend together, ribbon edges can look jagged, and overlapping parts may be difficult to distinguish. Before changing the visual model or rearranging the scene, try tuning a few real-time rendering effects that address these specific problems.
In SAMSON, quick switches and presets are available under Visualization > Options. For finer adjustments, open Interface > Preferences > Rendering. A useful approach is to change one effect at a time: it makes the visual difference easier to judge and helps prevent a clear view from becoming unnecessarily dark or busy.
1. Add depth with ambient occlusion
Ambient occlusion darkens regions that are less exposed to light, helping the eye perceive depth and contact. It can be especially useful when a molecule’s folds or neighboring parts appear to run together. SAMSON offers screen-space ambient occlusion, which is efficient but sensitive to camera distance, and object-space ambient occlusion, which is more realistic but slower.
For a quick first test, switch on screen-space ambient occlusion in Visualization > Options. Compare the same view with the effect off and on. The goal is to make structural depth easier to read—not simply to make every groove as dark as possible.
2. Separate overlapping regions with silhouettes
When regions at different depths meet visually, silhouettes can make their boundaries easier to follow. This is useful for ribbon representations, where a clear outline can help distinguish one structural element from another. Enable silhouettes from Visualization > Options, then adjust their settings in Preferences > Rendering > Silhouettes. The documentation’s example uses a thickness of 1; treat that as a starting point, then check whether the outlines clarify the structure without dominating it.
3. Smooth edges without ignoring performance
Jagged pixel boundaries can distract from the shape of a molecule, especially in curved ribbons and diagonal edges. Anti-aliasing reduces this effect. Fast Approximate Anti-Aliasing (FXAA) is typically efficient, and the Higher quality preset combines FXAA with a multisampling factor of 2. By comparison, Best speed uses a multisampling factor of 1 and no FXAA.
There is a trade-off: anti-aliasing requires additional GPU rendering and may slow visualization for large systems. If interaction becomes sluggish, try a faster setting and see whether the improved responsiveness is more valuable for the current task than smoother edges.
A practical order for tuning
- Choose a view and visual model that show the structural feature you want to inspect.
- Try ambient occlusion to strengthen depth cues.
- Add silhouettes if neighboring regions still run together.
- Adjust anti-aliasing to balance smooth edges with responsive interaction.
- Toggle each effect off and on in the same view to check that it genuinely improves readability.
These effects change how the viewport is presented; they do not replace choosing an appropriate visual model or camera view. For interactive appearance settings and additional effects, see the SAMSON rendering effects documentation.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON.