Nebulore

1"use client";
2 
3import { useEffect, useMemo, useRef } from "react";
4import { cn } from "@/lib/utils";
5 
6const vertexShaderGLSL = `
7attribute vec2 position;
8varying vec2 vUv;
9 
10void main() {
11  vUv = position * 0.5 + 0.5;
12  gl_Position = vec4(position, 0.0, 1.0);
13}
14`;
15 
16const fragmentShaderGLSL = `
17precision highp float;
18 
19varying vec2 vUv;
20 
21uniform vec2 u_resolution;
22uniform float u_time;
23uniform float u_speed;
24uniform float u_grain;
25uniform vec3 u_colors[3];
26 
27vec3 mod289(vec3 x) { return x - floor(x * (1.0 / 289.0)) * 289.0; }
28vec2 mod289(vec2 x) { return x - floor(x * (1.0 / 289.0)) * 289.0; }
29vec3 permute(vec3 x) { return mod289(((x * 34.0) + 1.0) * x); }
30 
31float snoise(vec2 v) {
32  const vec4 C = vec4(0.211324865405187, 0.366025403784439, -0.577350269189626, 0.024390243902439);
33  vec2 i = floor(v + dot(v, C.yy));
34  vec2 x0 = v - i + dot(i, C.xx);
35  vec2 i1 = (x0.x > x0.y) ? vec2(1.0, 0.0) : vec2(0.0, 1.0);
36  vec4 x12 = x0.xyxy + C.xxzz;
37  x12.xy -= i1;
38  i = mod289(i);
39  vec3 p = permute(permute(i.y + vec3(0.0, i1.y, 1.0)) + i.x + vec3(0.0, i1.x, 1.0));
40  vec3 m = max(0.5 - vec3(dot(x0, x0), dot(x12.xy, x12.xy), dot(x12.zw, x12.zw)), 0.0);
41  m = m * m;
42  m = m * m;
43  vec3 x = 2.0 * fract(p * C.www) - 1.0;
44  vec3 h = abs(x) - 0.5;
45  vec3 ox = floor(x + 0.5);
46  vec3 a0 = x - ox;
47  m *= 1.79284291400159 - 0.85373472095314 * (a0 * a0 + h * h);
48  vec3 g;
49  g.x = a0.x * x0.x + h.x * x0.y;
50  g.yz = a0.yz * x12.xz + h.yz * x12.yw;
51  return 130.0 * dot(m, g);
52}
53 
54float fbm(vec2 p) {
55  float value = 0.0;
56  float amplitude = 0.5;
57  mat2 rot = mat2(0.87, 0.48, -0.48, 0.87);
58 
59  for (int i = 0; i < 5; i++) {
60    value += amplitude * snoise(p);
61    p = rot * p * 2.05;
62    amplitude *= 0.5;
63  }
64 
65  return value;
66}
67 
68void main() {
69  vec2 uv = vUv;
70  float ratio = u_resolution.x / max(u_resolution.y, 1.0);
71  vec2 p = (uv - 0.5) * vec2(ratio, 1.0);
72  float t = u_time * u_speed;
73 
74  vec2 warp = vec2(
75    fbm(p * 1.4 + vec2(t * 0.08, t * 0.04)),
76    fbm(p * 1.4 + vec2(-t * 0.06, t * 0.05) + 4.2)
77  );
78  vec2 q = p + warp * 0.35;
79 
80  float ribbonA = abs(snoise(vec2(q.x * 1.8 + t * 0.12, q.y * 2.4 - t * 0.08)));
81  float ribbonB = abs(snoise(vec2(q.x * 2.6 - t * 0.1, q.y * 1.6 + t * 0.06 + ribbonA)));
82  float nebula = pow(1.0 - smoothstep(0.0, 0.55, ribbonA + ribbonB * 0.6), 2.2);
83 
84  float drift = fbm(p * 0.9 + vec2(t * 0.05, -t * 0.03));
85  nebula *= smoothstep(-0.4, 0.8, drift + 0.2);
86  nebula *= smoothstep(0.05, 0.55, uv.y) * smoothstep(1.0, 0.35, uv.y);
87 
88// … truncated