.p-summary
  h1 Particles

canvas(id="canvas-webgl", class="p-canvas-webgl")

script(id="vs-physics-renderer" type="x-shader/x-vertex").
  varying vec2 vUv;

  void main(void) {
    vUv = uv;
    gl_Position = vec4(position, 1.0);
  }

script(id="fs-physics-renderer-velocity-init" type="x-shader/x-fragment").
  uniform sampler2D velocity;

  varying vec2 vUv;

  void main(void) {
    gl_FragColor = texture2D(velocity, vUv);
  }

script(id="fs-physics-renderer-velocity" type="x-shader/x-fragment").
  uniform sampler2D velocity;
  uniform sampler2D acceleration;
  uniform float time;

  varying vec2 vUv;

  vec3 polar(float radian1, float radian2, float radius) {
    return vec3(
      cos(radian1) * cos(radian2) * radius,
      sin(radian1) * radius,
      cos(radian1) * sin(radian2) * radius
    );
  }

  void main(void) {
    vec3 v = texture2D(acceleration, vUv).xyz + texture2D(velocity, vUv).xyz;
    float vStep = step(1000.0, length(v));
    gl_FragColor = vec4(
      v * (1.0 - vStep) + normalize(v + polar(time, -time, 1.0)) * 80.0 * vStep,
      1.0
    );
  }

script(id="fs-physics-renderer-acceleration" type="x-shader/x-fragment").
  uniform vec2 resolution;
  uniform sampler2D velocity;
  uniform sampler2D acceleration;
  uniform float time;
  uniform vec2 vTouchMove;

  varying vec2 vUv;

  //
  // GLSL textureless classic 3D noise "cnoise",
  // with an RSL-style periodic variant "pnoise".
  // Author:  Stefan Gustavson (stefan.gustavson@liu.se)
  // Version: 2011-10-11
  //
  // Many thanks to Ian McEwan of Ashima Arts for the
  // ideas for permutation and gradient selection.
  //
  // Copyright (c) 2011 Stefan Gustavson. All rights reserved.
  // Distributed under the MIT license. See LICENSE file.
  // https://github.com/ashima/webgl-noise
  //

  vec3 mod289(vec3 x)
  {
    return x - floor(x * (1.0 / 289.0)) * 289.0;
  }

  vec4 mod289(vec4 x)
  {
    return x - floor(x * (1.0 / 289.0)) * 289.0;
  }

  vec4 permute(vec4 x)
  {
    return mod289(((x*34.0)+1.0)*x);
  }

  vec4 taylorInvSqrt(vec4 r)
  {
    return 1.79284291400159 - 0.85373472095314 * r;
  }

  vec3 fade(vec3 t) {
    return t*t*t*(t*(t*6.0-15.0)+10.0);
  }

  // Classic Perlin noise
  float cnoise(vec3 P)
  {
    vec3 Pi0 = floor(P); // Integer part for indexing
    vec3 Pi1 = Pi0 + vec3(1.0); // Integer part + 1
    Pi0 = mod289(Pi0);
    Pi1 = mod289(Pi1);
    vec3 Pf0 = fract(P); // Fractional part for interpolation
    vec3 Pf1 = Pf0 - vec3(1.0); // Fractional part - 1.0
    vec4 ix = vec4(Pi0.x, Pi1.x, Pi0.x, Pi1.x);
    vec4 iy = vec4(Pi0.yy, Pi1.yy);
    vec4 iz0 = Pi0.zzzz;
    vec4 iz1 = Pi1.zzzz;

    vec4 ixy = permute(permute(ix) + iy);
    vec4 ixy0 = permute(ixy + iz0);
    vec4 ixy1 = permute(ixy + iz1);

    vec4 gx0 = ixy0 * (1.0 / 7.0);
    vec4 gy0 = fract(floor(gx0) * (1.0 / 7.0)) - 0.5;
    gx0 = fract(gx0);
    vec4 gz0 = vec4(0.5) - abs(gx0) - abs(gy0);
    vec4 sz0 = step(gz0, vec4(0.0));
    gx0 -= sz0 * (step(0.0, gx0) - 0.5);
    gy0 -= sz0 * (step(0.0, gy0) - 0.5);

    vec4 gx1 = ixy1 * (1.0 / 7.0);
    vec4 gy1 = fract(floor(gx1) * (1.0 / 7.0)) - 0.5;
    gx1 = fract(gx1);
    vec4 gz1 = vec4(0.5) - abs(gx1) - abs(gy1);
    vec4 sz1 = step(gz1, vec4(0.0));
    gx1 -= sz1 * (step(0.0, gx1) - 0.5);
    gy1 -= sz1 * (step(0.0, gy1) - 0.5);

    vec3 g000 = vec3(gx0.x,gy0.x,gz0.x);
    vec3 g100 = vec3(gx0.y,gy0.y,gz0.y);
    vec3 g010 = vec3(gx0.z,gy0.z,gz0.z);
    vec3 g110 = vec3(gx0.w,gy0.w,gz0.w);
    vec3 g001 = vec3(gx1.x,gy1.x,gz1.x);
    vec3 g101 = vec3(gx1.y,gy1.y,gz1.y);
    vec3 g011 = vec3(gx1.z,gy1.z,gz1.z);
    vec3 g111 = vec3(gx1.w,gy1.w,gz1.w);

    vec4 norm0 = taylorInvSqrt(vec4(dot(g000, g000), dot(g010, g010), dot(g100, g100), dot(g110, g110)));
    g000 *= norm0.x;
    g010 *= norm0.y;
    g100 *= norm0.z;
    g110 *= norm0.w;
    vec4 norm1 = taylorInvSqrt(vec4(dot(g001, g001), dot(g011, g011), dot(g101, g101), dot(g111, g111)));
    g001 *= norm1.x;
    g011 *= norm1.y;
    g101 *= norm1.z;
    g111 *= norm1.w;

    float n000 = dot(g000, Pf0);
    float n100 = dot(g100, vec3(Pf1.x, Pf0.yz));
    float n010 = dot(g010, vec3(Pf0.x, Pf1.y, Pf0.z));
    float n110 = dot(g110, vec3(Pf1.xy, Pf0.z));
    float n001 = dot(g001, vec3(Pf0.xy, Pf1.z));
    float n101 = dot(g101, vec3(Pf1.x, Pf0.y, Pf1.z));
    float n011 = dot(g011, vec3(Pf0.x, Pf1.yz));
    float n111 = dot(g111, Pf1);

    vec3 fade_xyz = fade(Pf0);
    vec4 n_z = mix(vec4(n000, n100, n010, n110), vec4(n001, n101, n011, n111), fade_xyz.z);
    vec2 n_yz = mix(n_z.xy, n_z.zw, fade_xyz.y);
    float n_xyz = mix(n_yz.x, n_yz.y, fade_xyz.x);
    return 2.2 * n_xyz;
  }

  #define PRECISION 0.000001
  vec3 drag(vec3 a, float value) {
    return normalize(a * -1.0 + PRECISION) * length(a) * value;
  }

  void main(void) {
    vec3 v = texture2D(velocity, vUv).xyz;
    vec3 a = texture2D(acceleration, vUv).xyz;
    vec3 d = drag(a, 0.02);
    float fx = cnoise(vec3(time * 0.1, v.y / 500.0, v.z / 500.0));
    float fy = cnoise(vec3(v.x / 500.0, time * 0.1, v.z / 500.0));
    float fz = cnoise(vec3(v.x / 500.0, v.y / 500.0, time * 0.1));
    vec3 f1 = vec3(fx, fy, fz) * 0.12;
    vec3 f2 = vec3(vTouchMove * 10.0, 0.0);
    gl_FragColor = vec4(a + f1 + f2 + d, 1.0);
  }

script(id="vs-points" type="x-shader/x-vertex").
  attribute vec3 position;
  attribute vec2 uvVelocity;

  uniform mat4 modelViewMatrix;
  uniform mat4 projectionMatrix;
  uniform float time;
  uniform sampler2D acceleration;
  uniform sampler2D velocity;

  varying vec3 vAcceleration;

  void main() {
    vec3 a = texture2D(acceleration, uvVelocity).xyz;
    vec3 v = texture2D(velocity, uvVelocity).xyz;
    vec4 mvPosition = modelViewMatrix * vec4(v, 1.0);
    vAcceleration = a;
    gl_PointSize = 1.0 * (1200.0 / length(mvPosition.xyz));
    gl_Position = projectionMatrix * mvPosition;
  }

script(id="fs-points" type="x-shader/x-fragment").
  precision highp float;

  uniform float time;

  varying vec3 vAcceleration;

  vec3 convertHsvToRgb(vec3 c) {
    vec4 K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
    vec3 p = abs(fract(c.xxx + K.xyz) * 6.0 - K.www);
    return c.z * mix(K.xxx, clamp(p - K.xxx, 0.0, 1.0), c.y);
  }

  void main() {
    float start = smoothstep(time, 0.0, 1.0);
    vec3 n;
    n.xy = gl_PointCoord * 2.0 - 1.0;
    n.z = 1.0 - dot(n.xy, n.xy);
    if (n.z < 0.0) discard;
    float aLength = length(vAcceleration);
    vec3 color = convertHsvToRgb(vec3(aLength * 0.08 + time * 0.05, 0.5, 0.8));
    gl_FragColor = vec4(color, 0.4 * start);
  }
View Compiled
@import url('https://fonts.googleapis.com/css?family=Homenaje');

.p-canvas-webgl {
  position: fixed;;
  z-index: 1;
  top: 0; left: 0;
}

.p-summary {
  position: absolute;
  top: 5%; left: 5%;
  z-index: 2;
  color: #fff;
  font-family: 'Homenaje', sans-serif;
  h1 {
    font-weight: 400;
    letter-spacing: 0.2em;
  }
  p {
    letter-spacing: 0.2em;
  }
  a {
    color: #fff;
  }
}
View Compiled
class PhysicsRenderer {
  constructor(aVertexShader, aFragmentShader, vVertexShader, vFragmentShader) {
    this.length = 0;
    this.aScene = new THREE.Scene();
    this.vScene = new THREE.Scene();
    this.camera = new THREE.PerspectiveCamera(45, 1, 1, 1000);
    this.option = {
      type: THREE.FloatType,
      minFilter: THREE.LinearFilter,
      magFilter: THREE.NearestFilter
    };
    this.acceleration = [
      new THREE.WebGLRenderTarget(length, length, this.option),
      new THREE.WebGLRenderTarget(length, length, this.option),
    ];
    this.velocity = [
      new THREE.WebGLRenderTarget(length, length, this.option),
      new THREE.WebGLRenderTarget(length, length, this.option),
    ];
    this.aUniforms = {
      resolution: {
        type: 'v2',
        value: new THREE.Vector2(window.innerWidth, window.innerHeight),
      },
      velocity: {
        type: 't',
        value: null,
      },
      acceleration: {
        type: 't',
        value: null,
      },
      time: {
        type: 'f',
        value: 0
      }
    };
    this.vUniforms = {
      resolution: {
        type: 'v2',
        value: new THREE.Vector2(window.innerWidth, window.innerHeight),
      },
      velocity: {
        type: 't',
        value: null,
      },
      acceleration: {
        type: 't',
        value: null,
      },
      time: {
        type: 'f',
        value: 0
      }
    };
    this.accelerationMesh = this.createMesh(
      this.aUniforms,
      aVertexShader,
      aFragmentShader
    );
    this.velocityMesh = this.createMesh(
      this.vUniforms,
      vVertexShader,
      vFragmentShader
    );
    this.uvs = [];
    this.targetIndex = 0;
  }
  init(renderer, velocityArrayBase) {
    this.length = Math.ceil(Math.sqrt(velocityArrayBase.length / 3));
    const velocityArray = [];
    for (var i = 0; i < Math.pow(this.length, 2) * 3; i += 3) {
      if(velocityArrayBase[i] != undefined) {
        velocityArray[i + 0] = velocityArrayBase[i + 0];
        velocityArray[i + 1] = velocityArrayBase[i + 1];
        velocityArray[i + 2] = velocityArrayBase[i + 2];
        this.uvs[i / 3 * 2 + 0] = (i / 3) % this.length / (this.length - 1);
        this.uvs[i / 3 * 2 + 1] = Math.floor((i / 3) / this.length) / (this.length - 1);
      } else {
        velocityArray[i + 0] = 0;
        velocityArray[i + 1] = 0;
        velocityArray[i + 2] = 0;
      }
    }
    const velocityInitTex = new THREE.DataTexture(new Float32Array(velocityArray), this.length, this.length, THREE.RGBFormat, THREE.FloatType);
    velocityInitTex.needsUpdate = true;
    const velocityInitMesh = new THREE.Mesh(
      new THREE.PlaneBufferGeometry(2, 2),
      new THREE.ShaderMaterial({
        uniforms: {
          velocity: {
            type: 't',
            value: velocityInitTex,
          },
        },
        vertexShader: document.getElementById('vs-physics-renderer').textContent,
        fragmentShader: document.getElementById('fs-physics-renderer-velocity-init').textContent,
      })
    );
    for (var i = 0; i < 2; i++) {
      this.acceleration[i].setSize(this.length, this.length);
      this.velocity[i].setSize(this.length, this.length);
    }
    this.vScene.add(this.camera);
    this.vScene.add(velocityInitMesh);
    renderer.render(this.vScene, this.camera, this.velocity[0]);
    renderer.render(this.vScene, this.camera, this.velocity[1]);
    this.vScene.remove(velocityInitMesh);
    this.vScene.add(this.velocityMesh);
    this.aScene.add(this.accelerationMesh);
  }
  createMesh(uniforms, vs, fs) {
    return new THREE.Mesh(
      new THREE.PlaneBufferGeometry(2, 2),
      new THREE.ShaderMaterial({
        uniforms: uniforms,
        vertexShader: vs,
        fragmentShader: fs,
      })
    );
  }
  render(renderer, time) {
    const prevIndex = Math.abs(this.targetIndex - 1);
    const nextIndex = this.targetIndex;
    this.aUniforms.acceleration.value = this.acceleration[prevIndex].texture;
    this.aUniforms.velocity.value = this.velocity[nextIndex].texture;
    renderer.render(this.aScene, this.camera, this.acceleration[nextIndex]);
    this.vUniforms.acceleration.value = this.acceleration[nextIndex].texture;
    this.vUniforms.velocity.value = this.velocity[nextIndex].texture;
    renderer.render(this.vScene, this.camera, this.velocity[prevIndex]);
    this.targetIndex = prevIndex;
    this.aUniforms.time.value += time;
    this.vUniforms.time.value += time;
  }
  getBufferAttributeUv() {
    return new THREE.BufferAttribute(new Float32Array(this.uvs), 2);
  }
  getCurrentVelocity() {
    return this.velocity[Math.abs(this.targetIndex - 1)].texture;
  }
  getCurrentAcceleration() {
    return this.acceleration[Math.abs(this.targetIndex - 1)].texture;
  }
  mergeAUniforms(obj) {
    this.aUniforms = Object.assign(this.aUniforms, obj);
  }
  mergeVUniforms(obj) {
    this.vUniforms = Object.assign(this.vUniforms, obj);
  }
  resize(length) {
    this.length = length;
    this.velocity[0].setSize(length, length);
    this.velocity[1].setSize(length, length);
    this.acceleration[0].setSize(length, length);
    this.acceleration[1].setSize(length, length);
  }
}

class Points {
  constructor() {
    this.uniforms = {
      time: {
        type: 'f',
        value: 0
      },
      velocity: {
        type: 't',
        value: null
      },
      acceleration: {
        type: 't',
        value: null
      }
    };
    this.physicsRenderer = null;
    this.vectorTouchMove = new THREE.Vector2(0, 0);
    this.vectorTouchMoveDiff = new THREE.Vector2(0, 0);
    this.obj = null;
  }
  init(renderer) {
    this.obj = this.createObj(renderer);
  }
  createObj(renderer) {
    const detail = (window.innerWidth > 768) ? 7 : 6;
    const geometry = new THREE.OctahedronBufferGeometry(400, detail);
    const verticesBase = geometry.attributes.position.array;
    const vertices = [];
    for (var i = 0; i < verticesBase.length; i+= 3) {
      vertices[i + 0] = verticesBase[i + 0] + (Math.random() * 2 - 1) * 400;
      vertices[i + 1] = verticesBase[i + 1] + (Math.random() * 2 - 1) * 400;
      vertices[i + 2] = verticesBase[i + 2] + (Math.random() * 2 - 1) * 400;
    }
    this.physicsRenderer = new PhysicsRenderer(
      document.getElementById('vs-physics-renderer').textContent,
      document.getElementById('fs-physics-renderer-acceleration').textContent,
      document.getElementById('vs-physics-renderer').textContent,
      document.getElementById('fs-physics-renderer-velocity').textContent,
    );
    this.physicsRenderer.init(renderer, vertices);
    this.physicsRenderer.mergeAUniforms({
      vTouchMove: {
        type: 'v2',
        value: this.vectorTouchMoveDiff
      }
    });
    this.uniforms.velocity.value = this.physicsRenderer.getCurrentVelocity();
    this.uniforms.acceleration.value = this.physicsRenderer.getCurrentAcceleration();
    geometry.addAttribute('uvVelocity', this.physicsRenderer.getBufferAttributeUv());
    return new THREE.Points(
      geometry,
      new THREE.RawShaderMaterial({
        uniforms: this.uniforms,
        vertexShader: document.getElementById('vs-points').textContent,
        fragmentShader: document.getElementById('fs-points').textContent,
        transparent: true,
        depthWrite: false,
        blending: THREE.AdditiveBlending,
      })
    )
  }
  render(renderer, time) {
    this.physicsRenderer.render(renderer, time);
    this.uniforms.time.value += time;
  }
  touchStart(v) {
    this.vectorTouchMove.copy(v);
  }
  touchMove(v) {
    this.vectorTouchMoveDiff.set(
      v.x - this.vectorTouchMove.x,
      v.y - this.vectorTouchMove.y
    );
    this.vectorTouchMove.copy(v);
  }
  touchEnd() {
    this.vectorTouchMove.set(0, 0);
    this.vectorTouchMoveDiff.set(0, 0);
  }
}

class ConsoleSignature {
  constructor() {
    this.message = `created by yoichi kobayashi`;
    this.url = `http://www.tplh.net`;
    this.show();
  }
  show() {
    if (navigator.userAgent.toLowerCase().indexOf('chrome') > -1) {
      const args = [
        `\n%c ${this.message} %c%c ${this.url} \n\n`,
        'color: #fff; background: #222; padding:3px 0;',
        'padding:3px 1px;',
        'color: #fff; background: #47c; padding:3px 0;',
      ];
      console.log.apply(console, args);
    } else if (window.console) {
      console.log(`${this.message} ${this.url}`);
    }
  }
}

const normalizeVector2 = function(vector) {
  vector.x = (vector.x / window.innerWidth) * 2 - 1;
  vector.y = - (vector.y / window.innerHeight) * 2 + 1;
};

const debounce = function(callback, duration) {
  var timer;
  return function(event) {
    clearTimeout(timer);
    timer = setTimeout(function(){
      callback(event);
    }, duration);
  };
}

const canvas = document.getElementById('canvas-webgl');
const renderer = new THREE.WebGLRenderer({
  antialias: false,
  canvas: canvas,
});
const scene = new THREE.Scene();
const camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 10000);
const clock = new THREE.Clock();

const vectorTouchStart = new THREE.Vector2();
const vectorTouchMove = new THREE.Vector2();
const vectorTouchEnd = new THREE.Vector2();
let isDrag = false;

const consoleSignature = new ConsoleSignature();

//
// process for this sketch.
//

const points = new Points();
points.init(renderer);

//
// common process
//
const resizeWindow = () => {
  canvas.width = window.innerWidth;
  canvas.height = window.innerHeight;
  camera.aspect = window.innerWidth / window.innerHeight;
  camera.updateProjectionMatrix();
  renderer.setSize(window.innerWidth, window.innerHeight);
}
const render = () => {
  const time = clock.getDelta();
  points.render(renderer, time);
  renderer.render(scene, camera);
}
const renderLoop = () => {
  render();
  requestAnimationFrame(renderLoop);
}
const touchStart = (isTouched) => {
  isDrag = true;
  points.touchStart(vectorTouchStart);
};
const touchMove = (isTouched) => {
  if (isDrag) points.touchMove(vectorTouchMove);
};
const touchEnd = (isTouched) => {
  isDrag = false;
  points.touchEnd();
};
const mouseOut = () => {
  isDrag = false;
  points.touchEnd();
};
const on = () => {
  window.addEventListener('resize', debounce(() => {
    resizeWindow();
  }), 1000);
  canvas.addEventListener('mousedown', function (event) {
    event.preventDefault();
    vectorTouchStart.set(event.clientX, event.clientY);
    normalizeVector2(vectorTouchStart);
    touchStart(false);
  });
  canvas.addEventListener('mousemove', function (event) {
    event.preventDefault();
    vectorTouchMove.set(event.clientX, event.clientY);
    normalizeVector2(vectorTouchMove);
    touchMove(false);
  });
  canvas.addEventListener('mouseup', function (event) {
    event.preventDefault();
    vectorTouchEnd.set(event.clientX, event.clientY);
    normalizeVector2(vectorTouchEnd);
    touchEnd(false);
  });
  canvas.addEventListener('touchstart', function (event) {
    event.preventDefault();
    vectorTouchStart.set(event.touches[0].clientX, event.touches[0].clientY);
    normalizeVector2(vectorTouchStart);
    touchStart(event.touches[0].clientX, event.touches[0].clientY, true);
  });
  canvas.addEventListener('touchmove', function (event) {
    event.preventDefault();
    vectorTouchMove.set(event.touches[0].clientX, event.touches[0].clientY);
    normalizeVector2(vectorTouchMove);
    touchMove(true);
  });
  canvas.addEventListener('touchend', function (event) {
    event.preventDefault();
    normalizeVector2(vectorTouchEnd);
    vectorTouchEnd.set(event.changedTouches[0].clientX, event.changedTouches[0].clientY);
    touchEnd(true);
  });
  window.addEventListener('mouseout', function () {
    event.preventDefault();
    vectorTouchEnd.set(0, 0);
    mouseOut();
  });
}

const init = () => {
  renderer.setSize(window.innerWidth, window.innerHeight);
  renderer.setClearColor(0x111111, 1.0);
  camera.position.set(0, 0, 1000);
  camera.lookAt(new THREE.Vector3());

  scene.add(points.obj);

  on();
  resizeWindow();
  renderLoop();
}
init();
View Compiled

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/three.js/84/three.min.js