/**
* @param points An array of [X, Y] coordinates
*/
function* convexHull(points) {
points.sort(function(a, b) {
return a[0] == b[0] ? a[1] - b[1] : a[0] - b[0];
});
var lower = [];
for (var i = 0; i < points.length; i++) {
while (
lower.length >= 2 &&
cross(lower[lower.length - 2], lower[lower.length - 1], points[i]) <= 0
) {
lower.pop();
}
lower.push(points[i]);
yield lower;
}
var upper = [];
for (var i = points.length - 1; i >= 0; i--) {
while (
upper.length >= 2 &&
cross(upper[upper.length - 2], upper[upper.length - 1], points[i]) <= 0
) {
upper.pop();
}
upper.push(points[i]);
yield lower.concat(upper);
}
lower.pop();
yield lower.concat(upper);
}
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
