import { useEffect, useRef } from "react";
// The drifting icon field from the marketing site (owpengram-site's
// BgIcons.vue), ported so the console's sign-in screen looks like the same
// product rather than a different one.
//
// Same 28 particles, same sizes, speeds, opacities and repulsion as the
// original -- this is meant to match, not to be a second interpretation of the
// idea.
// Inner markup for each icon, drawn as strokes on a 24x24 viewBox. These are
// source constants, never anything a user supplied, which is what makes
// injecting them as HTML below safe.
const ICON_PATHS = [
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];
const PARTICLE_COUNT = 28;
type Particle = {
x: number;
y: number;
vx: number;
vy: number;
size: number;
rot: number;
rotSpeed: number;
};
export function BgIcons() {
const hostRef = useRef(null);
useEffect(() => {
const host = hostRef.current;
if (!host) return;
// Someone who asked the system for less motion gets a still field rather
// than twenty-eight things drifting across their screen.
if (window.matchMedia?.("(prefers-reduced-motion: reduce)").matches) {
return;
}
const nodes = Array.from(host.querySelectorAll(".bg-icon"));
let particles: Particle[] = [];
function seed() {
const w = window.innerWidth;
const h = window.innerHeight;
const margin = 60;
particles = nodes.map((node) => {
const size = 22 + Math.random() * 30;
node.style.width = `${size}px`;
node.style.height = `${size}px`;
node.style.opacity = String(0.18 + Math.random() * 0.12);
return {
x: margin + Math.random() * Math.max(1, w - margin * 2),
y: margin + Math.random() * Math.max(1, h - margin * 2),
vx: (Math.random() - 0.5) * 0.3,
vy: (Math.random() - 0.5) * 0.3,
size,
rot: Math.random() * 360,
rotSpeed: (Math.random() - 0.5) * 0.08
};
});
}
let frame = 0;
function tick() {
const w = window.innerWidth;
const h = window.innerHeight;
for (let i = 0; i < particles.length; i++) {
const a = particles[i];
a.x += a.vx;
a.y += a.vy;
a.rot += a.rotSpeed;
// Bounce off the viewport edges so the field stays on screen.
const half = a.size / 2;
if (a.x < half) { a.x = half; a.vx *= -1; }
if (a.x > w - half) { a.x = w - half; a.vx *= -1; }
if (a.y < half) { a.y = half; a.vy *= -1; }
if (a.y > h - half) { a.y = h - half; a.vy *= -1; }
// Gentle mutual repulsion: without it the drift eventually clumps the
// icons into a corner and the field stops reading as a field.
for (let j = i + 1; j < particles.length; j++) {
const b = particles[j];
const dx = b.x - a.x;
const dy = b.y - a.y;
const dist = Math.sqrt(dx * dx + dy * dy);
const minDist = (a.size + b.size) / 2 + 20;
if (dist < minDist && dist > 0.01) {
const force = ((minDist - dist) / minDist) * 0.02;
const nx = dx / dist;
const ny = dy / dist;
a.vx -= nx * force;
a.vy -= ny * force;
b.vx += nx * force;
b.vy += ny * force;
}
}
}
// Written straight to the nodes: this runs every frame, and putting 28
// positions through React state would re-render the sign-in form sixty
// times a second to move some background art.
for (let i = 0; i < nodes.length; i++) {
const p = particles[i];
nodes[i].style.transform = `translate(${p.x}px, ${p.y}px) rotate(${p.rot}deg)`;
}
frame = requestAnimationFrame(tick);
}
seed();
frame = requestAnimationFrame(tick);
window.addEventListener("resize", seed);
return () => {
cancelAnimationFrame(frame);
window.removeEventListener("resize", seed);
};
}, []);
return (