1 files changed, 114 insertions, 2 deletions
diff --git a/modules/Geometry.test.js b/modules/Geometry.test.js
index b44f25d..bfac85f 100644
--- a/modules/Geometry.test.js
+++ b/modules/Geometry.test.js
@@ -1,6 +1,6 @@
 import { test, assert } from './test-assert.js';
 
-import { AABB, QTNode } from './Geometry.js';
+import { AABB, QTNode, QuadTree } from './Geometry.js';
 
 
 test('AABB correctly contains/excludes points', () => {
@@ -141,5 +141,117 @@ test('QTNode correctly inserts multiple points', () => {
 	assert.equal(node.subnode[2].type.toString(), 'QTNode.Empty');
 
 	assert.equal(node.subnode[3].type.toString(), 'QTNode.Leaf');
-	assert.deepEqual(node.subnode[3].point, p0);
+assert.deepEqual(node.subnode[3].point, p0);
 });
+
+
+const randomPoint = () => ({ x: Math.random(), y: Math.random() });
+
+
+test('QTNode correctly returns points in region', () => {
+	const node = new QTNode(0, 0, 1, 1);
+	let points = [];
+	for (let i=0; i<100; i++) {
+		const pt = randomPoint();
+		node.insert(pt);
+		points.push(pt);
+	}
+
+	const pointsInRegion = aabb => {
+		let pts = [];
+		for (let pt of points) {
+			if (aabb.contains(pt)) pts.push(pt);
+		}
+		return pts;
+	};
+
+	const region = new AABB(0.25, 0.25, 0.5, 0.5);
+	let bf_points = pointsInRegion(region);
+	let qt_points = node.getPointsInRegion(region);
+	const compare = (a, b) => {
+		if (a.x == b.x)
+			return b.y - a.y;
+		return b.x - a.x;
+	};
+	bf_points.sort(compare);
+	qt_points.sort(compare);
+	assert.deepEqual(bf_points, qt_points);});
+
+
+test('QuadTree correctly finds closest point for 10,000 random points', () => {
+	const tree = new QuadTree(1, 1);
+
+	let points = [];
+	for (let i=0; i<10000; i++) {
+		const pt = randomPoint();
+		tree.insert(pt);
+		points.push(pt);
+	}
+	
+	const distance = (a, b) => Math.sqrt((a.x - b.x)**2 + (a.y - b.y)**2);
+	const bf_closest = a => {
+		let closest = null;
+		let min_dist = 1000;
+		for (let b of points) {
+			let d = distance(a, b);
+			if (d < min_dist) {
+				min_dist = d;
+				closest = b;
+			}
+		}
+		return closest;
+	}
+
+	for (let i=0; i<10000; i++) {
+		const pt = randomPoint();
+		assert.deepEqual(bf_closest(pt), tree.closest(pt));
+	}
+});
+
+
+function benchmark(desc, f, iterations) {
+	process.stdout.write(`${desc}: `);
+	const start = process.uptime();
+	for (let i=0; i<iterations; i++) f();
+	const elapsed = process.uptime() - start;
+	console.log(`${elapsed} seconds`);
+}
+
+const closest_benchmark = () => {
+	const n_points = 1e5;
+	const iterations = 1e4;
+	console.log(`> benchmark get closest of ${n_points} random points ${iterations} times`);
+
+	const tree = new QuadTree(1, 1);
+	let points = [];
+	for (let i=0; i<n_points; i++) {
+		const pt = randomPoint();
+		tree.insert(pt);
+		points.push(pt);
+	}
+
+	const distance = (a, b) => Math.sqrt((a.x - b.x)**2 + (a.y - b.y)**2);
+	const bf_closest = a => {
+		let closest = null;
+		let min_dist = 1000;
+		for (let b of points) {
+			let d = distance(a, b);
+			if (d < min_dist) {
+				min_dist = d;
+				closest = b;
+			}
+		}
+		return closest;
+	}
+
+	benchmark('\tbrute force', () => {
+		const pt = randomPoint();
+		bf_closest(pt);
+	}, iterations);
+
+	benchmark('\tquadtree', () => {
+		const pt = randomPoint();
+		tree.closest(pt);
+	}, iterations);
+}
+closest_benchmark();