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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;
  uniform sampler2D u_tile;
  
  #define PI 3.141592653589793
  #define TAU 6.283185307179586
  
  // 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));
  }

  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);
  }
  
  
	float ease(float t, float b, float c, float d) {
		return -c*.5 * (cos(PI*t/d) - 1.) + b;
	}
  
  vec2 sqdroste(vec2 z) {
    
    float angle = atan(log(2.)/(.5*PI));
    z = cExp(cDiv(cLog(z), cExp(vec2(0,angle))*cos(angle))); 
    
    float t = mod(u_time, 1.);
    float l = 1. + t;
    l = l*l*l + 1.3; // I have no idea why hthis works, but it seems to. So YAR! This magic number basically just accounts for the "easing" that comes about because of the scaling down of the texture.
    
    z /= l;
    
    vec2 a_z = abs(z);
    float scale = exp2(-floor(log2(max(a_z.y, a_z.x))));
    z *= scale;
    
    return z;
  }

  void main() {
    vec2 uv = (gl_FragCoord.xy - 0.5 * u_resolution.xy) / min(u_resolution.y, u_resolution.x);
    
    uv = sqdroste(uv);
    vec2 frac = fract(uv);
    
    vec3 fragcolour = texture2D(u_tile, frac).rgb;

    gl_FragColor = vec4(fragcolour*(fragcolour*1.6+.1)*1.5,1.0);
  }
</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, tile;
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;
    loader.load('https://s3-us-west-2.amazonaws.com/s.cdpn.io/982762/holzv2_12.jpg', (tex)=> {
      tile = tex;
      tile.wrapS = THREE.RepeatWrapping;
      tile.wrapT = THREE.RepeatWrapping;
      tile.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_tile: { type: "t", value: tile },
    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 );
  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: 60,
  // 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 = delta * 0.0005;
  renderer.render( scene, camera );
  
  if(capturing) {
    capturer.capture( renderer.domElement );
  }
}