A molecular scene can contain all the right structural information and still be hard to read. Ribbons overlap, a protein seems to float in front of a surface, or the edges of a model look jagged. Often the problem is not the model—it is that the viewport is missing useful visual cues.
SAMSON’s real-time rendering effects can help make depth, separation, and shape easier to interpret. Rather than switching on every effect at once, treat them as a small set of tools: start with the cue that addresses the problem you see, then check whether the result is clearer.
Start with depth and contact
Ambient occlusion darkens regions that are less accessible to light, helping the eye distinguish recessed areas. Screen-space ambient occlusion is an efficient approximation, though its appearance is sensitive to camera distance. Object-space ambient occlusion is more realistic but slower. For an interactive first pass, try screen-space ambient occlusion and compare the scene with it off and on.
This comparison uses the Ribbons model of 1AF6. The point is not simply to make the image darker: look for whether folds and overlaps become easier to distinguish.
For a scene involving a molecule near another object, shadows can help communicate relative position. Compare the examples below: the graphene sheet behind 1YRF is easier to place in relation to the molecule when shadows are enabled. If performance is a concern, the documentation notes that older graphics cards may benefit from disabling shadows or choosing a lower preset.
Separate shapes without changing the model
Silhouettes can make regions at different depths easier to separate visually. They are especially worth testing when a ribbon structure blends into nearby parts of the scene. The documentation’s example uses the Ribbons visual model for 1YRF with silhouette thickness set to 1. As with other effects, compare the result against the unmodified view: the useful setting is the one that clarifies structure without distracting from it.
Anti-aliasing solves a different problem. It smooths jagged edges and reduces visible pixel boundaries. FXAA is described as an efficient option for many recent graphics cards; combining it with a multisampling factor of 2 corresponds to the “Higher quality” preset in the example. The tradeoff is GPU work, which may slow visualization for large systems. If responsiveness matters more than smooth edges, “Best speed” uses a multisampling factor of 1 with FXAA off.
Keep the background and lighting in service of the scene
A background is part of the visual explanation, not just decoration. SAMSON provides its default background, black, white, a user-defined gradient, and an image background. If the model is difficult to distinguish from the current background, try another option or adjust the custom gradient’s top and bottom colors.
Lighting offers more detailed control. Two point lights each have color, intensity, specular intensity, specular power, and position controls. High specular intensity can make surfaces look plastic; lower values make them look matte. Global Fresnel and ambient-light settings also affect the overall appearance. To reproduce the documented flat-lighting setup, set both light intensities to zero, ambient light to 0.8, and Fresnel power to zero.
A useful quick workflow is to identify the visual problem first, then test one relevant effect: ambient occlusion for recessed depth, shadows for relative positions, silhouettes for separating regions, or anti-aliasing for jagged edges. Switch effects on and off while viewing the same scene and camera angle. You can toggle many effects and presets through Visualization > Options; detailed parameters are in Preferences > Rendering.
For the complete reference to these effects, see Rendering effects in the SAMSON documentation.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON.