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示例

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/88/three.min.js">script>
<script id="vertexShader" type="x-shader/x-vertex">
    void main() {
        gl_Position = vec4( position, 1.0 );
    }
script>
<script id="fragmentShader" type="x-shader/x-fragment">
  uniform vec2 u_resolution;
  uniform vec2 u_mouse;
  uniform float u_time;
  uniform sampler2D u_noise;
  
  #define PI 3.141592653589793
  #define TAU 6.283185307179586
  
  const int octaves = 2;
  const float seed =43758.5453123;
  const float seed2 = 73156.8473192;
    
  // float r1 = 0.1 + ((u_mouse.y + 0.5) * .1);
  // float r2 = 0.4 + (u_mouse.x * .2);
  float r1 = 0.2;
  float r2 = 0.9;
  
  // These awesome complex Math functions curtesy of 
  // https://github.com/mkovacs/reim/blob/master/reim.glsl
  vec2 cCis(float r);
  vec2 cLog(vec2 c); // principal value
  vec2 cInv(vec2 c);
  float cArg(vec2 c);
  float cAbs(vec2 c);
  
  vec2 cMul(vec2 a, vec2 b);
  vec2 cDiv(vec2 a, vec2 b);

  vec2 cCis(float r)
  {
    return vec2( cos(r), sin(r) );
  }
  vec2 cExp(vec2 c)
  {
    return exp(c.x) * cCis(c.y);
  }
  vec2 cConj(vec2 c)
  {
    return vec2(c.x, -c.y);
  }
  vec2 cInv(vec2 c)
  {
    return cConj(c) / dot(c, c);
  }
  vec2 cLog(vec2 c)
  {
    return vec2( log( cAbs(c) ), cArg(c) );
  }
  float cArg(vec2 c)
  {
    return atan(c.y, c.x);
  }
  float cAbs(vec2 c)
  {
    return length(c);
  }
  vec2 cMul(vec2 a, vec2 b)
  {
    return vec2(a.x*b.x - a.y*b.y, a.x*b.y + a.y*b.x);
  }
  vec2 cDiv(vec2 a, vec2 b)
  {
    return cMul(a, cInv(b));
  }

  float hash(float p)
  {
    vec2 o = texture2D( u_noise, vec2((p+0.5)/256.0), -100.0 ).xy;
    return o.x;
  }
  vec2 hash(vec2 p)
  {
    vec2 o = texture2D( u_noise, (p+0.5)/256.0, -100.0 ).xy;
    return o - .5;
  }
  vec3 hash3(vec2 p)
  {
    vec3 o = texture2D( u_noise, (p+0.5)/256.0, -100.0 ).xyz;
    return o;
  }
  vec4 hash4(vec2 p)
  {
    vec4 o = texture2D( u_noise, (p+0.5)/256.0, -100.0 );
    return o;
  }

  // LUT Noise by Inigo Quilez - iq/2013
  // https://www.shadertoy.com/view/4sfGzS
  float noiseLUT( in vec3 x )
  {
    vec3 p = floor(x);
    vec3 f = fract(x);
    f = f*f*(3.0-2.0*f);
    vec2 uv = (p.xy+vec2(37.0,17.0)*p.z) + f.xy;
    vec2 rg = texture2D(u_noise, (uv+0.5)/256.0).yx - .5;
    return mix( rg.x, rg.y, f.z );
  }

  float fbm1(in vec2 _st, float seed) {
    float v = 0.0;
    float a = 0.5;
    vec2 shift = vec2(100.0);
    // Rotate to reduce axial bias
    mat2 rot = mat2(cos(0.5), sin(0.5),
                    -sin(0.5), cos(0.50));
    for (int i = 0; i < octaves; ++i) {
        v += a * noiseLUT(vec3(_st, 1.));
        // v += a * noise(_st, seed);
        _st = rot * _st * 2.0 + shift;
        a *= 0.4;
    }
    return v;
  }

  float pattern(vec2 uv, float seed, float time, inout vec2 q, inout vec2 r) {

    q = vec2( fbm1( uv + vec2(0.0,0.0), seed ),
                   fbm1( uv + vec2(5.2,1.3), seed ) );

    r = vec2( fbm1( uv + 4.0*q + vec2(1.7 - time / 2.,9.2), seed ),
                   fbm1( uv + 4.0*q + vec2(8.3 - time / 2.,2.8), seed ) );

    return fbm1( uv + 4.0*r, seed );
  }

  vec2 hash2(vec2 p)
  {
    vec2 o = texture2D( u_noise, (p+0.5)/256.0, -100.0 ).xy;
    return o;
  }
  
  vec3 hsb2rgb( in vec3 c ){
    vec3 rgb = clamp(abs(mod(c.x*6.0+vec3(0.0,4.0,2.0),
                             6.0)-3.0)-1.0,
                     0.0,
                     1.0 );
    rgb = rgb*rgb*(3.0-2.0*rgb);
    return c.z * mix( vec3(1.0), rgb, c.y);
  }
  
  vec3 domain(vec2 z){
    return vec3(hsb2rgb(vec3(atan(z.y,z.x)/TAU,1.,1.)));
  }
  vec3 colour(vec2 z) {
      return domain(z);
  }
  
  vec2 Droste(vec2 uv) {
    
    // 5. Take the tiled strips back to ordinary space.
    uv = cLog(uv); 
    // 4. Scale and rotate the strips
    float scale = log(r2/r1);
    float angle = atan(scale/(2.0*PI));
    uv = cDiv(uv, cExp(vec2(0,angle))*cos(angle)); 
    // 3. this simulates zooming in the tile
    uv -= u_time * .2;
    // 2. Tile the strips
    uv.x = mod(uv.x,log(r2/r1)); 
    // 1. Take the annulus to a strip
    uv = cExp(uv)*r1;
    
    return uv;
  }

  void main() {
    vec2 uv = (gl_FragCoord.xy - 0.5 * u_resolution.xy) / min(u_resolution.y, u_resolution.x);
    uv *= 2.;
    vec2 _uv = uv;
    vec2 polar = vec2(length(_uv), atan(uv.y, uv.x));
    
    uv = Droste(uv);
    
    float rInv = 1./length(uv);
    uv = uv * rInv - vec2(rInv, 1.);
    
    vec2 p;
    vec2 q;
    float pat = pattern(uv * 5., seed, u_time * 5., p, q);
    
    vec3 fragcolour = mix(
      mix(
        vec3(.9, .7, 0.),
        vec3(1., .55, 0.1),
        abs(q.x*p.y)*20.),
      vec3(.5, .3, 0.),
      pat
    );
    fragcolour -= smoothstep(-.1, .9, p.x) * .5;
    fragcolour += smoothstep(-.1, .5, p.y) * .5;
    
    fragcolour += (1. - length(_uv * 2.)) *.5 ;
    float lcol = clamp(length((_uv) * 4.) - .2, 0., 1.);
    
    float raynoise = fbm1(polar*10.-u_time*2., seed);
    
    fragcolour = mix(
      fragcolour, 
      vec3(sin(p.y * 10.), cos(q.y * 10.), pat * 2.) * .5 + 1.5, 
      clamp(
        abs(
          sin(polar.y * 50.)
        ) * 1. / length(_uv * _uv * 3.) * raynoise - .2, 
        0., 
        1.) * .2);
    
    fragcolour = mix(vec3(1.), fragcolour, lcol);
    

    gl_FragColor = vec4(fragcolour,1.0);
  }
script>


<div id="container" touch-action="none">div>

CSS

body {
  margin: 0;
  padding: 0;
}

#container {
  position: fixed;
  touch-action: none;
}

JS

/*
Most of the stuff in here is just bootstrapping. Essentially it's just
setting ThreeJS up so that it renders a flat surface upon which to draw 
the shader. The only thing to see here really is the uniforms sent to 
the shader. Apart from that all of the magic happens in the HTML view
under the fragment shader.
*/

let container;
let camera, scene, renderer;
let uniforms;

let loader=new THREE.TextureLoader();
let texture;
loader.setCrossOrigin("anonymous");
loader.load(
  'https://s3-us-west-2.amazonaws.com/s.cdpn.io/982762/noise.png',
  function do_something_with_texture(tex) {
    texture = tex;
    texture.wrapS = THREE.RepeatWrapping;
    texture.wrapT = THREE.RepeatWrapping;
    texture.minFilter = THREE.LinearFilter;
    init();
    animate();
  }
);

function init() {
  container = document.getElementById( 'container' );

  camera = new THREE.Camera();
  camera.position.z = 1;

  scene = new THREE.Scene();

  var geometry = new THREE.PlaneBufferGeometry( 2, 2 );

  uniforms = {
    u_time: { type: "f", value: 1.0 },
    u_resolution: { type: "v2", value: new THREE.Vector2() },
    u_noise: { type: "t", value: texture },
    u_mouse: { type: "v2", value: new THREE.Vector2() }
  };

  var material = new THREE.ShaderMaterial( {
    uniforms: uniforms,
    vertexShader: document.getElementById( 'vertexShader' ).textContent,
    fragmentShader: document.getElementById( 'fragmentShader' ).textContent
  } );
  material.extensions.derivatives = true;

  var mesh = new THREE.Mesh( geometry, material );
  scene.add( mesh );

  renderer = new THREE.WebGLRenderer();
  renderer.setPixelRatio( window.devicePixelRatio );

  container.appendChild( renderer.domElement );

  onWindowResize();
  window.addEventListener( 'resize', onWindowResize, false );

  document.addEventListener('pointermove', (e)=> {
    let ratio = window.innerHeight / window.innerWidth;
    uniforms.u_mouse.value.x = (e.pageX - window.innerWidth / 2) / window.innerWidth / ratio;
    uniforms.u_mouse.value.y = (e.pageY - window.innerHeight / 2) / window.innerHeight * -1;
    
    e.preventDefault();
  });
}

function onWindowResize( event ) {
  renderer.setSize( window.innerWidth, window.innerHeight );
  // renderer.setSize( 1000, 1000 );
  uniforms.u_resolution.value.x = renderer.domElement.width;
  uniforms.u_resolution.value.y = renderer.domElement.height;
}

function animate(delta) {
  requestAnimationFrame( animate );
  render(delta);
}






let capturer = new CCapture( { 
  verbose: true, 
  framerate: 30,
  // motionBlurFrames: 4,
  quality: 90,
  format: 'webm',
  workersPath: 'js/'
 } );
let capturing = false;

isCapturing = function(val) {
  if(val === false && window.capturing === true) {
    capturer.stop();
    capturer.save();
  } else if(val === true && window.capturing === false) {
    capturer.start();
  }
  capturing = val;
}
toggleCapture = function() {
  isCapturing(!capturing);
}

window.addEventListener('keyup', function(e) { if(e.keyCode == 68) toggleCapture(); });

let then = 0;
function render(delta) {
  
  uniforms.u_time.value = -11000 + delta * 0.0005;
  renderer.render( scene, camera );
  
  if(capturing) {
    capturer.capture( renderer.domElement );
  }
}