A molecular scene can contain all the right atoms and still be hard to interpret. Overlapping structures, crowded regions, and weak visual separation can make it difficult to tell what sits in front of what. Before changing the molecular model or reaching for a final render, try adjusting the real-time rendering effects: some are specifically useful for making depth and spatial relationships easier to read.
In SAMSON, quick switches and presets are available under Visualization > Options. For more control, open Preferences > Rendering. A useful approach is to change one effect at a time, so you can see whether it improves the particular problem in your scene.
Start with ambient occlusion for crowded regions
Ambient occlusion darkens areas that are less exposed to light. In a molecular view, this can make grooves, contacts, and tightly packed regions look more spatially defined. SAMSON provides screen-space and object-space ambient occlusion. Screen-space ambient occlusion is an efficient approximation, though its appearance depends on the camera distance. Object-space ambient occlusion is more realistic but slower.
For a quick first test, switch on screen-space ambient occlusion from Visualization > Options. Compare the same view with the effect off and on before deciding whether the extra shading helps. The example below shows a Ribbons model of 1AF6 without ambient occlusion and with screen-space ambient occlusion.
Use shadows to judge relative position
When one object is positioned near another—such as a protein close to a graphene sheet—it may be hard to judge their separation from shading alone. Shadows can provide an additional visual cue about relative position. Compare the two views below: the documentation example shows 1YRF relative to a graphene sheet, first without shadows and then with them.
Shadows can affect performance, particularly on older graphics cards. If the viewport becomes sluggish, try disabling them or choosing a lower preset rather than assuming the molecular scene itself is the problem.
Add silhouettes when boundaries disappear
Silhouettes help separate regions at different depths by emphasizing their outlines. They can be especially useful when a molecular representation has many overlapping curves or surfaces. Enable silhouettes from Visualization > Options, then adjust their settings under Preferences > Rendering > Silhouettes. The documentation’s example uses a Ribbons model of 1YRF with silhouette thickness set to 1.
A simple troubleshooting sequence
- Keep the camera fixed. Changing the view while comparing effects makes it harder to tell what each setting contributes.
- Try ambient occlusion first. Check whether additional shading clarifies packed or recessed regions.
- Add shadows for nearby objects. Use them when you need to judge how structures sit relative to a surface or to one another.
- Try silhouettes if outlines blend together. Adjust the effect until boundaries are visible without distracting from the structure.
- Check responsiveness. If the viewport slows down, turn off an effect or use a lower preset, especially with older graphics hardware.
These effects change the appearance of the interactive viewport; they do not replace choosing an appropriate molecular representation or arranging visibility. They are also distinct from offline, final-quality rendering. For more detail on these and other viewport effects, see the SAMSON rendering effects documentation.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON.