Feedback Pass for THREE.EffectComposer

FeedbackPass.js

import { Pass, RenderPass } from 'postprocessing';
const glslify = require('glslify');
const path = require('path');

export default class FeedbackPass extends Pass {
  constructor() {
    super("FeedbackPass");

    this.time = 0;
    this.lastUpdate = 0;

    this.bufferTexture = new THREE.WebGLRenderTarget( window.innerWidth, window.innerHeight, { minFilter: THREE.LinearFilter, magFilter: THREE.NearestFilter});
    this.bufferTexture2 = new THREE.WebGLRenderTarget( window.innerWidth, window.innerHeight, { minFilter: THREE.LinearFilter, magFilter: THREE.NearestFilter});
    
    this.renderPassLastBuffer = new RenderPass(this.scene, this.camera);
    
    this.quad.material = new THREE.ShaderMaterial({
      vertexShader: glslify(path.resolve(__dirname, '../shaders/noise.vert')),
      fragmentShader: glslify(path.resolve(__dirname, '../shaders/noise.frag')),
      uniforms: {
        time: { value: 0 },
        texture: { value: this.bufferTexture.texture, type: 't' },
        texture2: { value: null, type: 't' }
      }
    });
  }

  render(renderer, inputBuffer, outputBuffer, delta, stencilTest) {
    this.time += delta;
    
    this.quad.material.uniforms.time.value = this.time;
    this.quad.material.uniforms.texture2.value = inputBuffer.texture;

    renderer.render(this.scene, this.camera, this.bufferTexture2);

    var a = this.bufferTexture2;
    this.bufferTexture2 = this.bufferTexture;
    this.bufferTexture = a;
    this.quad.material.uniforms.texture.value = this.bufferTexture.texture;
    

    renderer.render(this.scene, this.camera, this.renderToScreen ? null : outputBuffer);
  }
}

noise.frag

#pragma glslify: snoise3 = require(glsl-noise/simplex/3d)

varying vec3 pos;
uniform sampler2D texture;
uniform sampler2D texture2;
uniform float time;

void main () {
  vec2 texCoord = .5 + pos.xy * .5;

  vec3 color = texture2D(texture, texCoord).rgb;
  color = texture2D(texture, texCoord + snoise3(pos.xyx + time) / (100. / color.r)).rgb;
  vec3 color2 = texture2D(texture2, texCoord).rgb;

  gl_FragColor = vec4(color * .98 + color2 * .5, 1.0);
}

noise.vert

varying vec3 pos;

void main () {
	pos = position.xyz;

  gl_Position = projectionMatrix * modelViewMatrix * vec4(pos, 1.0);
}