A molecular structure can be scientifically correct and still be difficult to present. When you need to shift attention from one part of a scene to another, abruptly hiding a model can make the transition feel jarring. A gradual fade offers a calmer option: the structure remains visible while it becomes less prominent, then disappears.
In SAMSON, the Disappear animation progressively changes the transparency of selected nodes. It can help when you want to clear visual space during a presentation, guide attention between stages, or make a model’s exit easier to follow. The key is to apply it to the right kind of node and give the fade enough room to read clearly.
Choose the right target
Start by selecting the nodes you want to fade. Disappear works on nodes that have a transparency attribute, including structural models, visual models, meshes, and labels. There is an important detail for molecular scenes: individual atoms and bonds do not have an opacity attribute. Their structural models do. If your goal is to fade atoms and bonds, apply the animation to the relevant structural model rather than selecting individual atoms or bonds.
For nodes without a transparency attribute, Disappear behaves similarly to the Hide animation. So if a selected object vanishes rather than gradually fading, check whether that node type supports transparency.
What the four keyframes do
After selecting the nodes, double-click Disappear in the Animation panel of the Animator. The effect contains four keyframes, with three distinct phases:
- Keyframes 1–2: the selected nodes remain fully opaque.
- Keyframes 2–3: their transparency increases progressively.
- Keyframes 3–4: they remain fully transparent.
This structure is useful for planning the transition. The first interval gives the model time to be seen before the fade starts. The middle interval is where the disappearance happens. The final interval leaves the objects transparent. You can move the keyframes to adjust when these phases occur in your presentation.
Make the transition easier to follow
Before changing the timing, decide what you want viewers to notice. If the model is important context, leave enough time for it to be visible before fading. If the fade is meant to make room for a different view or explanation, place the transition where that change makes sense. These are presentation choices rather than fixed settings: the animation’s keyframes can be moved to suit the sequence you are building.
You can also change how parameter values are interpolated between frames by modifying the animation’s easing curve. This affects the way the transition progresses between keyframes. If the fade feels too abrupt or too gradual, the easing curve is one of the available properties to review, alongside the keyframe positions.
A quick troubleshooting checklist: confirm that you selected the structural model if you want atoms and bonds to fade; check that the target node supports transparency; and review the positions of the four keyframes if the timing does not fit your sequence. Animation effects are available from the Animator’s Animation panel.
For the full instructions, see the SAMSON Disappear animation documentation.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON.