Showcase 17 · Timeline
Once More
Three suns pull on each other while their motion is recorded. Drag back along the timeline below to any moment and give one sun a single different push there. From that point a new future unfolds – the old one stays beside it as a ghost trail.
The live demo needs JavaScript. The explanation below is readable without it.
- Timeline
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- Pushes
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- Distance to the old future
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- Frames/s
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How it works
The three suns are three bodies of equal mass that attract each other according to Newton. They start on a slightly disturbed figure eight: calm at first, then increasingly chaotic. The whole evolution is computed in advance in small steps and stored as a recording; the timeline only moves a playhead along it. That is why going back is exact and the same moment always looks the same.
A push takes the state at the current moment, changes the velocity of a single sun and computes a new future from there. Up to that moment both timelines are identical; afterwards they drift apart – barely noticeable at first, then faster and faster. The old future stays visible as a dashed ghost trail, and on the timeline its line lifts further away the larger the distance between the two futures. A soft edge keeps the suns on the stage; it exists only here, not in physics. All colours come from the design tokens.