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25 lines
807 B
JavaScript
25 lines
807 B
JavaScript
async function findConvexHull(pts) {
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const { sortBy, uniqWith, isEqual } = await import('https://cdn.jsdelivr.net/npm/lodash@4.17.21/+esm');
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const sorted = sortBy(uniqWith(pts, isEqual), ['x', 'y']);
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const cross = (a, b, c) => (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x);
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const hull = [];
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for (const p of sorted) {
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while (hull.length >= 2 && cross(hull[hull.length - 2], hull[hull.length - 1], p) <= 0) hull.pop();
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hull.push(p);
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}
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const lowerLen = hull.length;
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for (let i = sorted.length - 2; i >= 0; i--) {
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const p = sorted[i];
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while (hull.length > lowerLen && cross(hull[hull.length - 2], hull[hull.length - 1], p) <= 0) hull.pop();
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hull.push(p);
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}
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hull.pop();
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return hull;
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}
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export default findConvexHull;
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// Generation time: 1.322s
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// Result: FAIL
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