A molecular scene can contain all the right structures and still be difficult to read. Overlapping regions may look like one surface, a molecule can seem to float in front of a sheet, or distant parts may compete for attention. These are often problems of visual depth, not missing molecular information.
In SAMSON, several real-time rendering effects can help make spatial relationships easier to see. The key is to choose an effect that addresses the problem you actually have—and to adjust effects one at a time, so you can tell what changed.
Start with the relationship you need to read
Before changing settings, identify what is hard to distinguish. Are neighboring regions blending together? Is it unclear which object is in front? Or are distant parts distracting from the area you are studying? Different effects help with different visual cues.
You can switch effects and presets quickly in Visualization > Options. For more control, open Interface > Preferences > Rendering and adjust the relevant section.
Use ambient occlusion for depth within a structure
Ambient occlusion darkens regions that are less accessible to light, adding shading that can make molecular shape easier to perceive. This can be a useful first step when a structure looks too flat.
SAMSON offers screen-space and object-space ambient occlusion. Screen-space ambient occlusion is efficient, though its appearance depends on camera distance. Object-space ambient occlusion is more realistic but slower. For an interactive view, try screen-space ambient occlusion first and check whether the result still reads well as you zoom or reposition the camera.
The comparison below shows a Ribbons model of 1AF6 without and with screen-space ambient occlusion.
Add shadows when relative position is unclear
Shading can suggest the shape of an object, but it may not be enough to show how two objects sit in relation to one another. Shadows provide another cue. They can make it easier to understand the position of a molecule relative to a surface behind it.
For example, the images below show 1YRF in relation to a graphene sheet. Compare the scene without shadows to the same scene with shadows, and look specifically at how clearly the separation between the molecule and sheet reads.
If performance is an issue on an older graphics card, the documentation recommends disabling shadows or choosing a lower preset.
Try silhouettes for overlapping regions
Silhouettes help separate regions at different depths by emphasizing their outlines. They can be useful when a molecular model has overlapping shapes or when the boundaries between regions are hard to follow. You can enable them from Visualization > Options, then adjust their settings in Preferences > Rendering > Silhouettes.
A practical test is to create a Ribbons visual model and enable silhouettes with the thickness set to 1. Check whether the outlines clarify the structure without distracting from the molecular detail.
Use fog to de-emphasize distant parts
Fog blends distant parts of the scene progressively with the background. It can help keep attention on the foreground when faraway objects are visually competing with it. The near and far distances define where fog begins and where nodes become invisible; strength controls how quickly the effect appears.
Because fog reduces the visibility of distant objects, use it when foreground focus is the goal—not when you need every part of the scene to remain equally prominent. Depth of field can also blur distant parts, but it simulates a camera effect rather than blending them with the background.
A simple adjustment order
- Improve shape: try ambient occlusion.
- Clarify object placement: enable shadows.
- Separate overlapping regions: try silhouettes.
- Reduce distant clutter: adjust fog, checking that important context remains visible.
Make one change at a time, then inspect the scene at the camera distance and angle you plan to use. A setting that helps at one zoom level may be less effective at another, particularly with screen-space ambient occlusion.
For more details on these controls and their settings, see the SAMSON rendering effects documentation.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON.