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import { test, assert } from '../test-assert.js';
import { AABB, QTNode, QuadTree } from './Geometry.js';
const RUN_BENCHMARKS = false;
test('AABB correctly contains/excludes points', () => {
const box = new AABB(0, 0, 1, 1);
// interior
assert.ok(box.contains({ x: 0.5, y: 0.5 }));
// upper left
assert.ok(!box.contains({ x: -1, y: -1 }));
// above
assert.ok(!box.contains({ x: 0.5, y: -1}));
// upper right
assert.ok(!box.contains({ x: 2, y: -1 }));
// left
assert.ok(!box.contains({ x: -1, y: 0.5 }));
// right
assert.ok(!box.contains({ x: 2, y: 0.5}));
// lower left
assert.ok(!box.contains({ x: -1, y: 2 }));
// below
assert.ok(!box.contains({ x: 0.5, y: 2}));
// lower right
assert.ok(!box.contains({ x: 2, y: 2 }));
});
test('AABB correctly intersects other AABBs', () => {
const box = new AABB(1, 1, 4, 4);
// interior
assert.ok(box.intersects(new AABB(2, 2, 2, 2,)));
// upper left
assert.ok(box.intersects(new AABB(0, 0, 4, 4)));
assert.ok(!box.intersects(new AABB(0, 0, 0.5, 0.5)));
// above
assert.ok(box.intersects(new AABB(2, 0, 2, 2)));
assert.ok(!box.intersects(new AABB(2, 0, 2, 0.5)));
// upper right
assert.ok(box.intersects(new AABB(2, 0, 4, 2)));
assert.ok(!box.intersects(new AABB(6, 0, 4, 2)));
// left
assert.ok(box.intersects(new AABB(0, 2, 2, 2)));
assert.ok(!box.intersects(new AABB(0, 2, 0.5, 2)));
// right
assert.ok(box.intersects(new AABB(4, 2, 2, 2)));
assert.ok(!box.intersects(new AABB(6, 2, 2, 2)));
// lower left
assert.ok(box.intersects(new AABB(0, 4, 4, 4)));
assert.ok(!box.intersects(new AABB(0, 6, 0.5, 0.5)));
// below
assert.ok(box.intersects(new AABB(2, 4, 2, 2)));
assert.ok(!box.intersects(new AABB(2, 6, 2, 0.5)));
// lower right
assert.ok(box.intersects(new AABB(2, 4, 4, 2)));
assert.ok(!box.intersects(new AABB(6, 6, 4, 2)));
});
test('AABB correctly handles points at the edges', () => {
const box = new AABB(0, 0, 1, 1);
assert.ok(box.contains({ x: 0, y: 0 }));
assert.ok(box.contains({ x: 0.5, y: 0 }));
assert.ok(box.contains({ x: 0, y: 0.5 }));
// bad corners
assert.ok(!box.contains({ x: 1, y: 0 }));
assert.ok(!box.contains({ x: 0, y: 1 }));
assert.ok(!box.contains({ x: 1, y: 1 }));
// bad edges
assert.ok(!box.contains({ x: 1, y: 0.5 }));
assert.ok(!box.contains({ x: 0.5, y: 1 }));
});
test('QTNode correctly inserts points', () => {
const node = new QTNode(0, 0, 1, 1);
assert.equal(node.type.toString(), 'QTNode.Empty');
let result = node.insert({ x: -1, y: -1 }); // out of range, should not insert
assert.ok(!result);
assert.equal(node.type.toString(), 'QTNode.Empty');
result = node.insert({ x: 0.5, y: 0.5 }); // in range
assert.ok(result);
assert.equal(node.type.toString(), 'QTNode.Leaf');
assert.deepEqual(node.point, { x: 0.5, y: 0.5 });
});
test('QTNode correctly subdivides', () => {
const node = new QTNode(0, 0, 2, 2);
assert.ok(!node.subnode);
node.subdivide();
assert.equal(node.subnode.length, 4);
assert.deepEqual(node.subnode[0], new QTNode(0, 0, 1, 1));
assert.deepEqual(node.subnode[1], new QTNode(1, 0, 1, 1));
assert.deepEqual(node.subnode[2], new QTNode(0, 1, 1, 1));
assert.deepEqual(node.subnode[3], new QTNode(1, 1, 1, 1));
});
test('QTNode correctly inserts multiple points', () => {
const node = new QTNode(0, 0, 2, 2);
const p0 = { x: 1, y: 1 };
const p1 = { x: 0.5, y: 0.5 };
const oob = { x: 10, y: 15 };
assert.ok(node.insert(p0));
assert.ok(node.insert(p1));
assert.ok(!node.insert(oob));
assert.equal(node.type.toString(), 'QTNode.Branch');
assert.equal(node.subnode[0].type.toString(), 'QTNode.Leaf');
assert.deepEqual(node.subnode[0].point, p1);
assert.equal(node.subnode[1].type.toString(), 'QTNode.Empty');
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);
});
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('QTNode correctly removes immediate child point', () => {
const node = new QTNode(0, 0, 1, 1);
const pt = randomPoint();
node.insert(pt);
assert.deepEqual(node.type, QTNode.Leaf);
const pt2 = randomPoint();
node.remove(pt2);
assert.deepEqual(node.type, QTNode.Leaf);
assert.deepEqual(node.point, pt);
node.remove(pt);
assert.deepEqual(node.type, QTNode.Empty);
assert.equal(node.point, undefined);
});
test('QTNode correctly removes point from branch', () => {
for (let i=0; i<100; i++) {
const node = new QTNode(0, 0, 1, 1);
const pt1 = randomPoint();
const pt2 = randomPoint();
const pt3 = randomPoint();
node.insert(pt1); node.insert(pt2); node.insert(pt3);
assert.deepEqual(node.type, QTNode.Branch);
node.remove(pt1);
// should still be a branch because there are two child points yet
assert.deepEqual(node.type, QTNode.Branch);
node.remove(pt2);
// just one now, should be a leaf
assert.deepEqual(node.type, QTNode.Leaf);
node.remove(pt3);
// empty
assert.deepEqual(node.type, QTNode.Empty);
}
});
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);
}
if (RUN_BENCHMARKS)
closest_benchmark();
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