const turtle = new Turtle(); let polygons = new Polygons(); const step = 5; // min=1, max=5, step=1 const density = 8; // min=4, max=10, step=1 const shape = 15; // min=10, max=20, step=1 const radius = 500; // min=100, max=3000, step=100 const seed = 2;// min=2, max=200, step=1 let groups; let points; let random; function init() { random = new Random(seed); groups = []; points = new PoissonDisc(random, [[0, 0]], density).addPoints(radius); polygons = new Polygons(); const takenPoints = []; loop1: for (let p1 of points) { if (takenPoints.indexOf(p1) < 0) { var group = []; loop2: for (let p2 of points) { if (takenPoints.indexOf(p2) < 0) { if (distance(p1, p2) < shape) { group.push(p2); if (takenPoints.indexOf(p1) < 0) { takenPoints.push(p1); } takenPoints.push(p2); if (group.length >= 10) { break loop2; } } } } if (group.length > 2) { var mid = [0, 0]; for (let p of group) { mid[0] += p[0]; mid[1] += p[1]; } mid[0] /= group.length; mid[1] /= group.length; group.sort((a, b) => (angle(mid,a) - Math.PI) - (angle(mid,b) - Math.PI)); groups.push({group: group, mid:mid}); } } } groups.sort((a, b) => a.mid[1] - b.mid[1]); } // let animation = 0; //min=0, max=1, step=0.01 function walk(i, anim) { // if (anim === 1) anim = animation; if (i == 0) init(); let _step = 1; switch (step) { case _step++: { if (points[i][2]) { turtle.jump(points[i]); turtle.circle(0.4); } return i < points.length - 1; } case _step++: { if (points[i][2]) { turtle.jump(points[i]); turtle.circle(0.4); } let g = groups.pop(); if (g != null) { let group = g.group; for (let j = 0; j < group.length; j++) { let p1 = group[j]; let p2 = group[(j + 1) % group.length]; turtle.jump(p2[0], p2[1]); turtle.goto(p1[0], p1[1]); turtle.goto(p2[0], p2[1]); } let p = group[0]; turtle.goto(p[0], p[1]); } return groups.length > 0 || i < points.length - 1; } case _step++: { let g = groups.pop(); if (g) { let group = g.group; let h = Math.min(distance([0, 0], group[0]) / (85), 1); h = 1 - Math.pow(1 - h, 1 + random.next()); h = 1 - h; h *= 100; h += 3; group.forEach(p => { p[1] += 45; p[1] /= 2; }); for (let j = 0; j < group.length; j++) { let p1 = group[j]; let p2 = group[(j + 1) % group.length]; turtle.jump(p2[0], p2[1]); turtle.goto(p2[0], p2[1] - h); turtle.goto(p1[0], p1[1] - h); turtle.goto(p1[0], p1[1]); turtle.goto(p2[0], p2[1]); } let p = group[0]; turtle.goto(p[0], p[1]); } return groups.length > 0; } case _step++: case _step++: { let g = groups.pop(); if (g ) { let group = g.group; if (g.mid[0]>-100 && g.mid[0]<100) { let h = Math.min(distance([0, 0], group[0]) / (85), 1); h = 1 - Math.pow(1 - h, 1 + random.next()); h -= (0.5 + Math.sin(groups.length + anim*Math.PI*2)/2) / 6 * (1-anim); h = 1 - h; h *= 100; h += 3; group.forEach(p => { p[1] += 45; p[1] /= 2; }); const roofShape = polygons.create(); group.forEach((_, j) => roofShape.addPoints([group[j][0], group[j][1] - h]) ); roofShape.addOutline(); polygons.draw(turtle, roofShape, true); const segments = []; group.forEach((_, i) => segments.push( [group[i], group[(i+1) % group.length]] )); segments.sort( (s0, s1) => Math.max(s1[0][1], s1[1][1]) - Math.max(s0[0][1], s0[1][1])); segments.forEach( segment => { const p1 = segment[0]; const p2 = segment[1]; if ( p2[0]-p1[0] < 0 ) { const shape = polygons.create(); shape.addPoints( [p2[0], p2[1]], [p2[0], p2[1] - h], [p1[0], p1[1] - h], [p1[0], p1[1]], [p2[0], p2[1]] ); if (step > 4) { const v = [p2[0] - p1[0], p2[1] - p1[1]]; const length = distance(v); const normal = [v[1] / length, -v[0] / length]; let lightAngle = 2.1; // min=0, max=7, step=0.01 lightAngle += anim * Math.PI*2; const lightDirection = [Math.sin(lightAngle), Math.cos(lightAngle)]; const diff = lightDirection[0] * normal[0] + lightDirection[1] * normal[1]; let hatching = 0.2 + (0.5 + diff * 0.5) * 2; // 0.2 - 2 // make light parts super light if (hatching > 1.4) { let d = (hatching - 1.4) * 2; const ease = t => Math.pow(2, 10.0 * (t - 1.0)); hatching = hatching-0.5 + ease(d) * 0.5; } if (hatching < 9) { shape.addHatching(Math.PI/4, hatching); } } shape.addOutline(); polygons.draw(turtle, shape, true); } }); } } return groups.length > 0; } } } function modulo(i, n) { // positive modulo return (n + (i % n)) % n; } const __EMPTY_ = [0,0]; function distance(p1, p2 = __EMPTY_) { var delta = [p1[0] - p2[0], p1[1] - p2[1]]; return Math.sqrt(delta[0] * delta[0] + delta[1] * delta[1]); } function angle(a, b) { return Math.atan2(a[1] - b[1], a[0] - b[0]); } // Seeded random - Mulberry32 function Random(seed) { class Random { constructor(seed) { this.seed = seed; } next() { var t = this.seed += 0x6D2B79F5; t = Math.imul(t ^ t >>> 15, t | 1); t ^= t + Math.imul(t ^ t >>> 7, t | 61); return ((t ^ t >>> 14) >>> 0) / 4294967296; } shuffle(arr) { for (let i = arr.length - 1; i > 0; i--) { const j = Math.floor(this.next() * (i + 1)); [arr[i], arr[j]] = [arr[j], arr[i]]; } return arr; } } return new Random(seed); } // Forked from "Poisson- Disc Grow Patterns" by reinder // https://turtletoy.net/turtle/b5510898dc //////////////////////////////////////////////////////////////// // Poisson-Disc utility code. Created by Reinder Nijhoff 2019 // https://turtletoy.net/turtle/b5510898dc //////////////////////////////////////////////////////////////// function PoissonDisc(random, startPoints, radius) { class PoissonDiscGrid { constructor(sp, radius) { this.cellSize = 1/Math.sqrt(2)/radius; this.radius2 = radius*radius; this.cells = []; sp.forEach( p => this.insert(p) ); } insert(p) { const x = p[0]*this.cellSize|0, y=p[1]*this.cellSize|0; for (let xi = x-1; xi<=x+1; xi++) { for (let yi = y-1; yi<=y+1; yi++) { const ps = this.cell(xi,yi); for (let i=0; i<ps.length; i++) { if ((ps[i][0]-p[0])**2 + (ps[i][1]-p[1])**2 < this.radius2) { return false; } } } } this.cell(x, y).push(p); return true; } cell(x,y) { const c = this.cells; return (c[x]?c[x]:c[x]=[])[y]?c[x][y]:c[x][y]=[]; } } class PoissonDisc { constructor(random, sp, radius) { this.result = [...sp]; this.active = [...sp]; this.grid = new PoissonDiscGrid(sp, radius); this.random = random; } addPoints(count, maxTries=16, loosePacking=0, randomGrowOrder=0) { mainLoop: while (this.active.length > 0 && count > 0) { const index = (this.random.next() * this.active.length * randomGrowOrder) | 0; const point = this.active[index]; for (let i=0; i < maxTries; i++) { const a = this.random.next() * 2 * Math.PI; const d = (this.random.next()*loosePacking + 1) * radius; const p = [point[0] + Math.cos(a)*d, point[1] + Math.sin(a)*d, point]; if (this.grid.insert(p)) { this.result.push(p); this.active.push(p); count--; continue mainLoop; } } this.active.splice(index, 1); } return this.result; } } return new PoissonDisc(random, startPoints, radius); } //////////////////////////////////////////////////////////////// // Polygon Clipping utility code - Created by Reinder Nijhoff 2019 // https://turtletoy.net/turtle/a5befa1f8d //////////////////////////////////////////////////////////////// function Polygons() { const polygonList = []; const Polygon = class { constructor() { this.cp = []; // clip path: array of [x,y] pairs this.dp = []; // 2d lines [x0,y0],[x1,y1] to draw this.aabb = []; // AABB bounding box } addPoints(...points) { // add point to clip path and update bounding box let xmin = 1e5, xmax = -1e5, ymin = 1e5, ymax = -1e5; (this.cp = [...this.cp, ...points]).forEach( p => { xmin = Math.min(xmin, p[0]), xmax = Math.max(xmax, p[0]); ymin = Math.min(ymin, p[1]), ymax = Math.max(ymax, p[1]); }); this.aabb = [(xmin+xmax)/2, (ymin+ymax)/2, (xmax-xmin)/2, (ymax-ymin)/2]; } addSegments(...points) { // add segments (each a pair of points) points.forEach(p => this.dp.push(p)); } addOutline() { for (let i = 0, l = this.cp.length; i < l; i++) { this.dp.push(this.cp[i], this.cp[(i + 1) % l]); } } draw(t) { for (let i = 0, l = this.dp.length; i < l; i+=2) { t.jump(this.dp[i]), t.goto(this.dp[i + 1]); } } addHatching(a, d) { const tp = new Polygon(); tp.cp.push([-1e5,-1e5],[1e5,-1e5],[1e5,1e5],[-1e5,1e5]); const dx = Math.sin(a) * d, dy = Math.cos(a) * d; const cx = Math.sin(a) * 200, cy = Math.cos(a) * 200; for (let i = 0.5; i < 150 / d; i++) { tp.dp.push([dx * i + cy, dy * i - cx], [dx * i - cy, dy * i + cx]); tp.dp.push([-dx * i + cy, -dy * i - cx], [-dx * i - cy, -dy * i + cx]); } tp.boolean(this, false); this.dp = [...this.dp, ...tp.dp]; } inside(p) { let int = 0; // find number of i ntersection points from p to far away for (let i = 0, l = this.cp.length; i < l; i++) { if (this.segment_intersect(p, [0.1, -1000], this.cp[i], this.cp[(i + 1) % l])) { int++; } } return int & 1; // if even your outside } boolean(p, diff = true) { // bouding box optimization by ge1doot. if (Math.abs(this.aabb[0] - p.aabb[0]) - (p.aabb[2] + this.aabb[2]) >= 0 && Math.abs(this.aabb[1] - p.aabb[1]) - (p.aabb[3] + this.aabb[3]) >= 0) return this.dp.length > 0; // polygon diff algorithm (narrow phase) const ndp = []; for (let i = 0, l = this.dp.length; i < l; i+=2) { const ls0 = this.dp[i]; const ls1 = this.dp[i + 1]; // find all intersections with clip path const int = []; for (let j = 0, cl = p.cp.length; j < cl; j++) { const pint = this.segment_intersect(ls0, ls1, p.cp[j], p.cp[(j + 1) % cl]); if (pint !== false) { int.push(pint); } } if (int.length === 0) { // 0 intersections, inside or outside? if (diff === !p.inside(ls0)) { ndp.push(ls0, ls1); } } else { int.push(ls0, ls1); // order intersection points on line ls.p1 to ls.p2 const cmpx = ls1[0] - ls0[0]; const cmpy = ls1[1] - ls0[1]; int.sort( (a,b) => (a[0] - ls0[0]) * cmpx + (a[1] - ls0[1]) * cmpy - (b[0] - ls0[0]) * cmpx - (b[1] - ls0[1]) * cmpy); for (let j = 0; j < int.length - 1; j++) { if ((int[j][0] - int[j+1][0])**2 + (int[j][1] - int[j+1][1])**2 >= 0.001) { if (diff === !p.inside([(int[j][0]+int[j+1][0])/2,(int[j][1]+int[j+1][1])/2])) { ndp.push(int[j], int[j+1]); } } } } } return (this.dp = ndp).length > 0; } //port of http://paulbourke.net/geometry/pointlineplane/Helpers.cs segment_intersect(l1p1, l1p2, l2p1, l2p2) { const d = (l2p2[1] - l2p1[1]) * (l1p2[0] - l1p1[0]) - (l2p2[0] - l2p1[0]) * (l1p2[1] - l1p1[1]); if (d === 0) return false; const n_a = (l2p2[0] - l2p1[0]) * (l1p1[1] - l2p1[1]) - (l2p2[1] - l2p1[1]) * (l1p1[0] - l2p1[0]); const n_b = (l1p2[0] - l1p1[0]) * (l1p1[1] - l2p1[1]) - (l1p2[1] - l1p1[1]) * (l1p1[0] - l2p1[0]); const ua = n_a / d; const ub = n_b / d; if (ua >= 0 && ua <= 1 && ub >= 0 && ub <= 1) { return [l1p1[0] + ua * (l1p2[0] - l1p1[0]), l1p1[1] + ua * (l1p2[1] - l1p1[1])]; } return false; } }; return { list: () => polygonList, create: () => new Polygon(), draw: (turtle, p, addToVisList=true) => { for (let j = 0; j < polygonList.length && p.boolean(polygonList[j]); j++); p.draw(turtle); if (addToVisList) polygonList.push(p); } }; }