# Out-of-Focus Bokeh Lights A shadcn/ui block from the [@weinc](https://we.inc/components?utm_source=shadcn.exchange) registry, listed on [shadcn.exchange](https://shadcn.exchange/r/weinc/out-of-focus-bokeh-lights-particle-background). - Page, with a live preview: https://shadcn.exchange/r/weinc/out-of-focus-bokeh-lights-particle-background - Screenshot: https://shadcn.exchange/shot/weinc/out-of-focus-bokeh-lights-particle-background/light.png - Registry item: https://we.inc/r/out-of-focus-bokeh-lights-particle-background.json - Listed: 2026-10-28, source last changed 2026-10-28 ## Install ```bash npx shadcn@latest add https://shadcn.exchange/r/weinc/out-of-focus-bokeh-lights-particle-background.json ``` Run it in a project that has shadcn/ui set up. It adds the files below and installs what they depend on. ## Files ### `components/we-inc/out-of-focus-bokeh-lights-particle-background.tsx` ```tsx import { useEffect, useRef } from "react"; // Out-of-Focus Bokeh Lights: a canvas 2D particle background behind a small hero. // Sprites are drawn once to small offscreen canvases, motion is scaled by frame // time, the loop stops off screen, and reduced motion gets one settled frame. // Values worth changing: const LIGHTS_PER_MPX = 48; // out-of-focus lights per million pixels const COLOURS = ["255,186,104", "255,226,182", "238,142,118", "150,196,214"]; // light colours, as r,g,b const DRIFT = 1; // how fast the lights float const FOCUS_BREATH = 1; // how much the lens seems to breathe in and out of focus const WARMUP = 1; // frames simulated before the first paint type Ptr = { x: number; y: number; on: boolean }; type Scene = { update: (dt: number, t: number) => void; draw: (c: CanvasRenderingContext2D, t: number) => void }; function glow(size: number, rgb: string, stops: number[][]): HTMLCanvasElement { const c = document.createElement("canvas"); c.width = c.height = size; const g = c.getContext("2d")!; const r = size / 2; const grd = g.createRadialGradient(r, r, 0, r, r, r); for (const [o, a] of stops) grd.addColorStop(o, `rgba(${rgb},${a})`); g.fillStyle = grd; g.fillRect(0, 0, size, size); return c; } function mount(canvas: HTMLCanvasElement, root: HTMLElement): () => void { const ctx = canvas.getContext("2d"); if (!ctx) return () => {}; const still = window.matchMedia("(prefers-reduced-motion: reduce)").matches; const ptr: Ptr = { x: -1e4, y: -1e4, on: false }; let w = 0, h = 0, t = 0, last = 0, raf = 0, seen = true; let scene: Scene | null = null; const fit = () => { const r = canvas.getBoundingClientRect(); if (scene && Math.abs(r.width - w) < 1 && Math.abs(r.height - h) < 1) return; const dpr = Math.min(window.devicePixelRatio || 1, 1.5); w = Math.max(1, r.width); h = Math.max(1, r.height); canvas.width = Math.round(w * dpr); canvas.height = Math.round(h * dpr); ctx.setTransform(dpr, 0, 0, dpr, 0, 0); scene = createScene(w, h, ptr); for (let i = 0; i < WARMUP; i++) { t += 1 / 30; scene.update(1 / 30, t); } scene.draw(ctx, t); }; const frame = (now: number) => { const dt = Math.min(0.05, Math.max(0, (now - last) / 1000)); last = now; t += dt; if (scene) { scene.update(dt, t); scene.draw(ctx, t); } raf = requestAnimationFrame(frame); }; const run = () => { cancelAnimationFrame(raf); raf = 0; if (!still && seen && !document.hidden) { last = performance.now(); raf = requestAnimationFrame(frame); } }; const ro = new ResizeObserver(fit); ro.observe(canvas); const io = new IntersectionObserver((es) => { seen = es[es.length - 1].isIntersecting; run(); }); io.observe(canvas); document.addEventListener("visibilitychange", run); fit(); run(); return () => { cancelAnimationFrame(raf); ro.disconnect(); io.disconnect(); document.removeEventListener("visibilitychange", run); }; } function createScene(w: number, h: number, _ptr: Ptr): Scene { const area = (w * h) / 1e6; // Real lens bokeh is a flat disc with a slightly brighter rim, not a soft blob. const disc = (rgb: string, edge: number) => { const c = document.createElement("canvas"); c.width = c.height = 128; const g = c.getContext("2d")!; const grd = g.createRadialGradient(64, 64, 0, 64, 64, 62); grd.addColorStop(0, `rgba(${rgb},0.30)`); grd.addColorStop(0.78, `rgba(${rgb},0.36)`); grd.addColorStop(0.93 - edge, `rgba(${rgb},0.62)`); grd.addColorStop(1, `rgba(${rgb},0)`); g.fillStyle = grd; g.beginPath(); g.arc(64, 64, 62, 0, 7); g.fill(); return c; }; const sharp = COLOURS.map((rgb) => disc(rgb, 0)); const soft = COLOURS.map((rgb) => glow(128, rgb, [[0, 0.3], [0.6, 0.22], [1, 0]])); const ps = Array.from({ length: Math.max(14, Math.min(90, Math.round(area * LIGHTS_PER_MPX))) }, () => { const z = Math.random(); return { x: Math.random() * w, y: h * (0.15 + Math.random() * 0.9), z, k: Math.floor(Math.random() * COLOURS.length), s: Math.random() * 99, a: 0.35 + Math.random() * 0.55 }; }).sort((a, b) => a.z - b.z); return { update(dt, t) { for (const p of ps) { p.x += (3 + p.z * 9) * DRIFT * dt; p.y += Math.sin(t * 0.2 + p.s) * 3 * DRIFT * dt; if (p.x > w + 120) { p.x = -120; p.y = h * (0.15 + Math.random() * 0.9); } } }, draw(c, t) { c.clearRect(0, 0, w, h); c.globalCompositeOperation = "lighter"; const focus = Math.sin(t * 0.18) * FOCUS_BREATH; for (const p of ps) { const s = (24 + p.z * 120) * (1 + focus * 0.1 * p.z); c.globalAlpha = p.a * (0.55 + 0.45 * Math.sin(t * 0.5 + p.s)) * (1 - p.z * 0.35); c.drawImage(p.z > 0.7 ? soft[p.k] : sharp[p.k], p.x - s / 2, p.y - s / 2, s, s); } c.globalAlpha = 1; c.globalCompositeOperation = "source-over"; }, }; } export default function OutOfFocusBokehLights() { const canvasRef = useRef(null); const rootRef = useRef(null); useEffect(() => { if (!canvasRef.current || !rootRef.current) return; return mount(canvasRef.current, rootRef.current); }, []); return (
); } ```