OPTICS: Reachability Plot & Varying-Density Clustering

OPTICS is the density-based clustering algorithm that fixes DBSCAN's biggest weakness: a single global radius that cannot fit clusters of very different densities at once. This simulator generates a point cloud with deliberately uneven density — a tight cluster, a loose cluster, a very sparse cluster and scattered noise — then runs the real OPTICS ordering algorithm on it, visualizing both the raw 3D point cloud (colored by the clusters your threshold extracts) and the reachability plot the algorithm actually produces, as a bar chart in the same scene. Adjust ε and MinPts to change what counts as a neighborhood and a core point, then slide the extraction threshold to watch clusters merge, split and turn to noise directly on the reachability bars — the same interactive read that a data scientist does on a real OPTICS reachability plot before picking a cut.