Cursor Comet

1"use client";
2 
3import * as React from "react";
4 
5import { cn } from "@/lib/utils";
6import { useReducedMotion, useVisibilityPause } from "@/lib/motiq";
7 
8/* -------------------------------------------------------------------------- */
9/* Types                                                                      */
10/* -------------------------------------------------------------------------- */
11 
12export interface CursorCometProps extends React.HTMLAttributes<HTMLDivElement> {
13  /** Fixed particle pool size (clamped 24–800). No allocation happens per frame. */
14  particleBudget?: number;
15  /** 0–1 fraction of pointer velocity each particle inherits, reversed. */
16  velocityGain?: number;
17  /** Exponential drag coefficient, per second. */
18  drag?: number;
19  /** Head/young-particle color — any CSS color, resolved from tokens by default. */
20  headColor?: string;
21  /** Tail/old-particle color. */
22  tailColor?: string;
23  /** Ionization spark color — the rare signature moment. */
24  sparkColor?: string;
25  /** Pointer speed (px/s) above which coral sparks ignite at the head. */
26  sparkThreshold?: number;
27  /** Coil the particles into an ambient orbit ring when the pointer is away. */
28  idleOrbit?: boolean;
29  /** Deterministic seed for the particle jitter (SSR-stable markup). */
30  seed?: number;
31  /** Stop the rAF loop when scrolled offscreen or the tab is hidden. */
32  pauseWhenHidden?: boolean;
33  /** Force the static, motion-free variant regardless of system preference. */
34  reducedMotion?: boolean;
35}
36 
37/* -------------------------------------------------------------------------- */
38/* Helpers                                                                    */
39/* -------------------------------------------------------------------------- */
40 
41const clamp = (v: number, a: number, b: number) => (v < a ? a : v > b ? b : v);
42 
43/** mulberry32 — deterministic jitter, no Math.random at render or module scope. */
44function makeRng(seed: number) {
45  let a = seed >>> 0;
46  return () => {
47    a = (a + 0x6d2b79f5) | 0;
48    let t = Math.imul(a ^ (a >>> 15), 1 | a);
49    t = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t;
50    return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
51  };
52}
53 
54/** Resolve any computed CSS color string (rgb/rgba/#hex) to an [r,g,b] triple. */
55function parseRgb(input: string): [number, number, number] {
56  const c = input.trim();
57  if (c.startsWith("#")) {
58    let h = c.slice(1);
59    if (h.length === 3) h = h.split("").map((d) => d + d).join("");
60// … truncated