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-rw-r--r--src/modules/Geometry.js233
-rw-r--r--src/modules/Geometry.test.js259
-rw-r--r--src/modules/Mouse.js53
-rw-r--r--src/modules/Util.js20
-rw-r--r--src/modules/Util.test.js23
-rw-r--r--src/modules/test-assert.js21
6 files changed, 0 insertions, 609 deletions
diff --git a/src/modules/Geometry.js b/src/modules/Geometry.js
deleted file mode 100644
index 43f277f..0000000
--- a/src/modules/Geometry.js
+++ /dev/null
@@ -1,233 +0,0 @@
-'use strict';
-
-function dist(a, b) {
- return Math.sqrt((a.x - b.x)**2 + (a.y - b.y)**2);
-}
-
-/* AABB - axis-aligned bounding box */
-class AABB {
- /* create a new AABB */
- constructor(x, y, width, height) {
- this.x = x; this.y = y;
- this.width = width; this.height = height;
- }
-
- /* check if a point is inside the box
- *
- * a "point" is any object with an x- and y-coordinate.
- * any other data in the object is ignored.
- *
- * returns true if the point is inside, and false otherwise.
- */
- contains(point) {
- if (point.x >= this.x && point.y >= this.y
- && point.x < this.x + this.width
- && point.y < this.y + this.height)
- return true;
- return false;
- }
-
- /* check if two AABBs overlap */
- intersects(aabb) {
- const overlap = (ax, arange, bx, brange) => {
- const range = ax < bx ? arange : brange;
- if (Math.abs(bx - ax) < range)
- return true;
- return false;
- };
-
- if (overlap(this.x, this.width, aabb.x, aabb.width) &&
- overlap(this.y, this.height, aabb.y, aabb.height))
- return true;
- return false;
- }
-}
-
-
-/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *
- * QUADTREE
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- */
-
-/* lil enum class for QTNode types */
-class QTNodeType {
- constructor(name) { this.name = name; }
- toString() { return `QTNode.${this.name}`; }
-}
-
-
-/* nodes in a quadtree
- *
- * they can be either "Empty" (no point),
- * "Leaf" (they contain a point and no sub-nodes),
- * or "Branch" (they contain no point and have sub-nodes).
- * There are no QTNodes with children and point data.
- */
-class QTNode {
- static Empty = new QTNodeType('Empty');
- static Leaf = new QTNodeType('Leaf');
- static Branch = new QTNodeType('Branch');
-
- constructor(x, y, width, height) {
- this.aabb = new AABB(x, y, width, height);
- /* all QTNodes start empty */
- this.type = QTNode.Empty;
- }
-
- /* insert a point into the tree, starting with this node
- *
- * as above, points are just objects with 'x' and 'y' values.
- * other data in the point is not examined and is incorporated into the
- * tree.
- *
- * this function returns false if the point was not contained in the bounding box,
- * and true otherwise. inserting a point may cause the node's type to change
- * (e.g. a Leaf node would become a Branch node and its point data would be
- * moved lower in the tree).
- */
- insert(point) {
- if (this.aabb.contains(point)) {
- if (this.type == QTNode.Empty) {
- /* empty nodes are easy -- just switch to Leaf and add the point */
- this.type = QTNode.Leaf;
- this.point = point;
- return true;
- }
- else if (this.type == QTNode.Leaf) {
- /* Leaf must become a Branch */
- this.type = QTNode.Branch;
- this.subdivide();
-
- /* move current point into a child */
- let result = this.insert(this.point);
- if (!result) return false;
- this.point = undefined;
-
- /* add new point */
- return this.insert(point);
- }
- else {
- /* This is a Branch, and we should insert into a child node */
- /* just try them all until we find one where the point can go */
- if (this.subnode[0].insert(point)) return true;
- if (this.subnode[1].insert(point)) return true;
- if (this.subnode[2].insert(point)) return true;
- if (this.subnode[3].insert(point)) return true;
- return false; // something strange has happened!!
- }
- }
- /* point not in this node, return false */
- return false;
- }
-
- /* subdivide the node into four child nodes
- *
- * under normal circumstances, the user should not call this function --
- * it's just meant to be used during insertion.
- */
- subdivide() {
- /* some useful constants */
- const x = this.aabb.x; const y = this.aabb.y;
- const w = this.aabb.width/2; const h = this.aabb.height/2;
-
- /* generate sub-nodes */
- this.subnode = [
- new QTNode(x, y, w, h),
- new QTNode(x+w, y, w, h),
- new QTNode(x, y+h, w, h),
- new QTNode(x+w, y+h, w, h),
- ];
- }
-
- /* query the tree for all points contained within a region recursively
- *
- * returns an array containing any points in the tree beneath this node
- * that are inside the supplied AABB.
- */
- getPointsInRegion(aabb) {
- if (this.type == QTNode.Empty) return [];
- if (!this.aabb.intersects(aabb)) return [];
- if (this.type == QTNode.Leaf) return [this.point];
-
- /* Branch - recusively query children */
- return [
- ...this.subnode[0].getPointsInRegion(aabb),
- ...this.subnode[1].getPointsInRegion(aabb),
- ...this.subnode[2].getPointsInRegion(aabb),
- ...this.subnode[3].getPointsInRegion(aabb),
- ];
- }
-}
-
-
-/* full-blown quadtree! */
-class QuadTree {
- /* create a new quadtree */
- constructor(width, height) {
- this.root = new QTNode(0, 0, width, height);
- }
-
- /* insert a point into the tree */
- insert(point) {
- return this.root.insert(point);
- }
-
- /* get the closest tree point to the given point */
- closest(point) {
- /* the algorithm goes like this:
- * 1. find the smallest node containing the point
- * 2. the closest point is within a box at most 4x the
- * size of that lowest node, so query all points within
- * such a region.
- * 3. brute-force within the list of points.
- */
-
- /* recursively find the node containing a point */
- const getLeaf = (point, node) => {
- /* is point in bounding box? */
- if (!node.aabb.contains(point)) return null;
- /* is this a Leaf or Empty node? */
- if (node.type == QTNode.Empty ||
- node.type == QTNode.Leaf) return node;
-
- /* this is a branch node, so recurse */
- for (let subnode of node.subnode) {
- const leaf = getLeaf(point, subnode);
- if (leaf !== null) return leaf;
- }
-
- /* should never get here */
- return null;
- }
-
- /* find the node, starting at the tree root */
- const leaf = getLeaf(point, this.root);
- if (leaf === null) return leaf;
-
- /* construct the 4x AABB, centered on the query point */
- const dim = 2*Math.max(leaf.aabb.width, leaf.aabb.height);
- const region = new AABB(point.x - dim, point.y - dim, 2*dim, 2*dim);
-
- /* get all points */
- const points = this.root.getPointsInRegion(region);
-
- /* brute force search within the small list */
- let closest = null;
- let min_dist = 100 * this.root.aabb.width * this.root.aabb.height;
- const dist = (a, b) => (a.x - b.x)**2 + (a.y - b.y)**2;
- for (let pt of points) {
- const d = dist(point, pt);
- if (d < min_dist) {
- closest = pt;
- min_dist = d;
- }
- }
-
- /* done! */
- return closest;
- }
-}
-
-export { dist, AABB, QTNode, QuadTree };
diff --git a/src/modules/Geometry.test.js b/src/modules/Geometry.test.js
deleted file mode 100644
index 925a53d..0000000
--- a/src/modules/Geometry.test.js
+++ /dev/null
@@ -1,259 +0,0 @@
-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('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();
diff --git a/src/modules/Mouse.js b/src/modules/Mouse.js
deleted file mode 100644
index 0b8f922..0000000
--- a/src/modules/Mouse.js
+++ /dev/null
@@ -1,53 +0,0 @@
-class Mouse {
- constructor(ct) {
- this.ct = ct;
- this.x = 0;
- this.y = 0;
- this.radius = 0.005;
- this.show = false;
- this.pressed = false;
- this.onMove = null;
-
- window.addEventListener('mousemove', e => {
- /* get current transform matrix */
- const matrix = this.ct.getTransform();
- matrix.invertSelf();
-
- const x = e.offsetX; const y = e.offsetY;
- this.x = matrix.a*x + matrix.b*y;
- this.y = matrix.c*x + matrix.d*y;
-
- if (this.onMove) this.onMove();
- });
-
- const root = document.getElementById('root');
-
- root.addEventListener('mouseover', e => {
- e = e ? e : window.event;
- this.show = true;
- });
-
- root.addEventListener('mouseout', e => {
- e = e ? e: window.event;
- this.show = false;
- });
- }
-
- render(ct) {
- if (!this.show) return;
- console.log(this.radius);
- ct.save();
-
- ct.strokeStyle = '#fff';
-
- ct.beginPath();
- ct.arc(this.x, this.y, this.radius, 0, 2*Math.PI);
- ct.closePath();
- ct.stroke();
-
- ct.restore();
- }
-}
-
-
-export default Mouse;
diff --git a/src/modules/Util.js b/src/modules/Util.js
deleted file mode 100644
index 165d1d0..0000000
--- a/src/modules/Util.js
+++ /dev/null
@@ -1,20 +0,0 @@
-function useAverage() {
- var avg = 0;
- let weight = 0;
- const append = value => {
- avg = (weight * avg) + value;
- weight += 1;
- avg = avg/weight;
- }
-
- return [() => avg, append];
-}
-
-function clamp(value, min, max) {
- return Math.min(Math.max(value, min), max);
-}
-
-function lerp(a, b, alpha) {
- return ((1-alpha)*a) + (alpha*b);
-}
-export { useAverage, clamp, lerp };
diff --git a/src/modules/Util.test.js b/src/modules/Util.test.js
deleted file mode 100644
index 000d54e..0000000
--- a/src/modules/Util.test.js
+++ /dev/null
@@ -1,23 +0,0 @@
-import { test, assert} from './test-assert.js';
-import { useAverage } from './Util.js';
-
-
-test('Average correctly accumulates an average', () => {
- let [avg, avg_append] = useAverage();
- let data = [];
- for (let i=0; i<5000; i++) {
- let d = Math.random();
- data.push(d);
- avg_append(d);
- }
-
- let manual_average = 0;
- for (let d of data) manual_average += d;
- manual_average /= data.length;
-
- const precision = (decimalPlaces, num) => {
- const theta = 10**decimalPlaces;
- return Math.floor(num * theta) / theta;
- };
- assert.equal(precision(5, avg()), precision(5, manual_average));
-});
diff --git a/src/modules/test-assert.js b/src/modules/test-assert.js
deleted file mode 100644
index 7be2989..0000000
--- a/src/modules/test-assert.js
+++ /dev/null
@@ -1,21 +0,0 @@
-import { strict as assert } from 'node:assert';
-
-function test(description, func)
-{
- process.stdout.write(description);
- let error = null;
- try {
- func();
- }
- catch(err) {
- error = err;
- }
-
- if (error) {
- console.log(' - FAIL');
- console.log(error);
- }
- else console.log(' - OK');
-}
-
-export { test, assert };
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