Convex Hull Construction Screensaver
The Convex Hull Construction screensaver runs a real live Graham scan, building the tightest polygon that wraps a random point cloud, step by step. It is free, runs in your browser, and ESC exits.
How the Convex Hull Construction screensaver works
The saver scatters a real random cloud of points, then sorts them by angle around the lowest point, exactly as a real Graham scan requires.
It then walks the sorted points, pushing each onto a stack and popping back whenever three consecutive points would turn the wrong way.
Each push and pop is drawn live, so you watch the real hull boundary tighten into shape point by point.
Once the full convex hull is closed, it holds briefly, then a fresh random point cloud and hull build begins.
A worked example
A point that sits just inside the current boundary gets popped back off the hull the moment a later point makes the turn direction invalid, exactly matching the real Graham scan rule.
Settings & tips
- Accent recolours the hull boundary.
- The point cloud is real and randomized every run.
- A fresh point cloud generates automatically once the hull closes.
Frequently asked questions
- Is this a real computational geometry algorithm?
- Yes — a real, correct Graham scan implementation, run live on a randomized point cloud.
- What is a convex hull?
- The smallest convex polygon that contains every point in the set — a real, well-defined geometric shape.
- Is a key needed?
- No — it is a pure local computation.
- Is it free?
- Yes — free, no download, in your browser.