30:[] 2e:{"title":"Lightning","cells":[{"id":0,"value":"md`# Lightning`","pinned":false,"hidden":false,"mode":"ojs"},{"id":10,"value":"chart = chartOf(paths, {watermark: true, optimize:true, name:'lightning'})","pinned":false,"hidden":false,"mode":"ojs"},{"id":28,"value":"viewof seed = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":65,"value":"viewof periodx = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":148,"value":"viewof periody = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":164,"value":"viewof xdamp = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":54,"value":"viewof iter = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":188,"value":"viewof scale = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":173,"value":"viewof centre = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":81,"value":"viewof num = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":100,"value":"viewof rotmul = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":234,"value":"viewof xmul = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":229,"value":"viewof offx = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":231,"value":"viewof offy = html``","pinned":false,"hidden":false,"mode":"ojs"},{"id":4,"value":"paths = {\n noise.seed(seed)\n const TAU = Math.PI * 2\n\n const PERIODX = periodx\n const PERIODY = periody\n const particles = []\n const NUM=num\n const ITER=iter\n const ROTMULT = rotmul\n const SCALE = scale\n\n for (let i = 0; i < NUM; i++) {\n particles.push({\n x: centre,//(i/NUM * W - W/2) * 0.8,//Math.random() * W,\n // y: 0,// + Math.random() * 50,\n a: Math.PI * 2 * i / NUM,\n })\n }\n\n const abs = x => x < 0 ? -x : x\n\n const paths = particles.map(initial => {\n let pa = []\n\n let p = {x:initial.x, a:initial.a}\n for (let i = 0; i < ITER; i++) {\n const n = noise.simplex2(p.x * PERIODX, Math.sin(p.a) * PERIODY) * ROTMULT\n p.x += xmul * Math.cos(n)\n p.a += Math.sin(n) * xdamp\n\n pa.push([\n Math.sin(p.a + Math.PI / 2) * p.x * SCALE + offx,\n Math.cos(p.a + Math.PI / 2) * p.x * SCALE + offy\n ])\n }\n\n return pa\n })\n\n\n return paths\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":7,"value":"import {W, H, chartOf, lerp, download} from '@josephg/plotter-sketchpad'","pinned":false,"hidden":false,"mode":"ojs"},{"id":40,"value":"noise = require('https://bundle.run/simplenoise@1.0.1')","pinned":false,"hidden":false,"mode":"ojs"}],"files":"$W30","stdlib":"1","titling":"auto"}