WarpTunnel

1"use client"
2 
3import * as React from "react"
4import { useFrame } from "@react-three/fiber"
5import * as THREE from "three"
6 
7import {
8  SceneContainer,
9  type SceneContainerProps,
10} from "@/components/threecn/scene-container"
11import {
12  useShadcnTheme,
13  type ThemeMode,
14} from "@/components/hooks/use-shadcn-theme"
15 
16const NEAR_Z = 5
17const FAR_Z = -45
18 
19function randomStreak(spread: number, out: Float32Array, offset: number, z?: number) {
20  // Bias stars away from the exact center so the camera has a clear "eye".
21  const r = 0.4 + Math.sqrt(Math.random()) * spread
22  const a = Math.random() * Math.PI * 2
23  const x = Math.cos(a) * r
24  const y = Math.sin(a) * r * 0.65
25  const zz = z ?? FAR_Z + Math.random() * (NEAR_Z - FAR_Z)
26  const len = 1 + Math.random() * 1.6
27  out[offset] = x
28  out[offset + 1] = y
29  out[offset + 2] = zz
30  out[offset + 3] = x
31  out[offset + 4] = y
32  out[offset + 5] = zz - len
33}
34 
35function seedStreaks(count: number, spread: number) {
36  const positions = new Float32Array(count * 6)
37  for (let i = 0; i < count; i++) randomStreak(spread, positions, i * 6)
38  return positions
39}
40 
41function Streaks({
42  count,
43  speed,
44  spread,
45  theme,
46}: {
47  count: number
48  speed: number
49  spread: number
50  theme: ThemeMode
51}) {
52  const { primaryColor, foregroundColor, isDark } = useShadcnTheme(theme)
53  const geoRef = React.useRef<THREE.BufferGeometry>(null)
54 
55  const positions = React.useMemo(
56    () => seedStreaks(count, spread),
57    [count, spread]
58  )
59  const colors = React.useMemo(() => new Float32Array(count * 6), [count])
60 
61  // Head = bright (foreground tinted with primary), tail = dim primary so
62  // additive blending fades the streak out naturally.
63  React.useLayoutEffect(() => {
64    const geo = geoRef.current
65    if (!geo) return
66    const colorAttr = geo.getAttribute("color") as THREE.BufferAttribute
67    const arr = colorAttr.array as Float32Array
68    const head = new THREE.Color()
69      .copy(foregroundColor)
70      .lerp(primaryColor, 0.4)
71    const tail = new THREE.Color()
72      .copy(primaryColor)
73      .multiplyScalar(isDark ? 0.12 : 0.55)
74    for (let i = 0; i * 6 < arr.length; i++) {
75      const o = i * 6
76      arr[o] = head.r
77      arr[o + 1] = head.g
78      arr[o + 2] = head.b
79      arr[o + 3] = tail.r
80      arr[o + 4] = tail.g
81      arr[o + 5] = tail.b
82    }
83    colorAttr.needsUpdate = true
84  }, [count, primaryColor, foregroundColor, isDark])
85 
86  useFrame((_, delta) => {
87    const geo = geoRef.current
88    if (!geo) return
89// … truncated