A molecular scene can become difficult to follow when every structure, region, or annotation remains visible at once. Hiding elements manually may help while editing, but it can interrupt the flow of a presentation. The Flash animation offers a simple alternative: it changes whether selected nodes are visible at particular keyframes, so you can briefly reveal a part of a scene and then hide it again.
This is useful when a viewer needs to notice a specific component without permanently cluttering the molecular view. For example, you might use a flash to draw attention to a selected group, then return the scene to its less crowded state. The key point is that Flash controls visibility, not transparency. A node is shown or hidden; it does not gradually become translucent.
What the four keyframes do
Flash uses four keyframes to define a short visibility sequence:
- Between keyframes 1 and 2: the selected nodes stay hidden.
- At keyframe 2: they become visible, and remain visible between keyframes 2 and 3.
- At keyframe 3: they become hidden, and stay hidden between keyframes 3 and 4.
Thinking of the animation as a timed reveal helps when planning a presentation: the nodes are hidden before the reveal, visible for a span of the animation, then hidden afterward. The keyframes give you control over where that span falls in your sequence.
Set it up around the point you want to make
- Select the nodes you want the animation to affect. Consider selecting only the parts needed to make the point, so the reveal remains easy to interpret.
- Add Flash by double-clicking the effect in the Animation panel of the Animator.
- Position the keyframes to fit the surrounding presentation. The keyframes can be moved, so you can adjust when the nodes appear and disappear rather than rebuilding the animation.
- Preview the sequence and check whether the visible interval gives viewers enough time to identify the selected nodes. If the reveal feels rushed or out of place, adjust the keyframe positions.
A practical way to use Flash is to treat it like a visual cue, not a decoration. Ask what the audience should notice while the nodes are visible, and whether hiding them afterward makes the next part of the scene clearer. Because the effect switches visibility rather than transparency, it is best suited to a clear on/off reveal—not to showing a structure through another one.
Fine-tune the timing
You can change how parameters are interpolated between frames by modifying the animation’s Easing curve. If you are adjusting the animation’s feel, review the result in context with the rest of the sequence. The keyframes establish the hidden and visible portions; moving them is the direct way to change when those portions occur.
The Inspector also shows the Flash animation options:
Use Flash when a scene benefits from a timed, unambiguous reveal and disappearance. If your goal instead involves changing opacity, remember that Flash works through node visibility, not transparency. For the complete instructions, see the Flash animation documentation.
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