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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <script type="x-shader/x-fragment" id="reset-velocity">
  precision highp float;

  void main () {
    gl_FragColor = vec4(vec3(0.), 1.);
  }
</script>

<script type="x-shader/x-fragment" id="reset-position">
  precision highp float;

  uniform vec2 size;

  // https://github.com/mattdesl/glsl-random
  highp float random(vec2 co)
  {
      highp float a = 12.9898;
      highp float b = 78.233;
      highp float c = 43758.5453;
      highp float dt= dot(co.xy ,vec2(a,b));
      highp float sn= mod(dt,3.14);
      return fract(sin(sn) * c);
  }

  void main () {
    vec2 nPosition = gl_FragCoord.st / size * 2. - 1.;
    vec4 position = vec4(
      nPosition * size,
      0.,
      random(nPosition)
    );
    gl_FragColor = position;
  }
</script>

<script type="x-shader/x-fragment" id="velocity">
  precision highp float;

  uniform vec2 size;
  uniform sampler2D prevVelocityTexture;
  uniform sampler2D prevPositionTexture;

  //
  // Description : Array and textureless GLSL 2D/3D/4D simplex
  //               noise functions.
  //      Author : Ian McEwan, Ashima Arts.
  //  Maintainer : ijm
  //     Lastmod : 20110822 (ijm)
  //     License : Copyright (C) 2011 Ashima Arts. 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;
  }

  float snoise(vec3 v)
    {
    const vec2  C = vec2(1.0/6.0, 1.0/3.0) ;
    const vec4  D = vec4(0.0, 0.5, 1.0, 2.0);

  // First corner
    vec3 i  = floor(v + dot(v, C.yyy) );
    vec3 x0 =   v - i + dot(i, C.xxx) ;

  // Other corners
    vec3 g = step(x0.yzx, x0.xyz);
    vec3 l = 1.0 - g;
    vec3 i1 = min( g.xyz, l.zxy );
    vec3 i2 = max( g.xyz, l.zxy );

    //   x0 = x0 - 0.0 + 0.0 * C.xxx;
    //   x1 = x0 - i1  + 1.0 * C.xxx;
    //   x2 = x0 - i2  + 2.0 * C.xxx;
    //   x3 = x0 - 1.0 + 3.0 * C.xxx;
    vec3 x1 = x0 - i1 + C.xxx;
    vec3 x2 = x0 - i2 + C.yyy; // 2.0*C.x = 1/3 = C.y
    vec3 x3 = x0 - D.yyy;      // -1.0+3.0*C.x = -0.5 = -D.y

  // Permutations
    i = mod289(i);
    vec4 p = permute( permute( permute(
                i.z + vec4(0.0, i1.z, i2.z, 1.0 ))
              + i.y + vec4(0.0, i1.y, i2.y, 1.0 ))
              + i.x + vec4(0.0, i1.x, i2.x, 1.0 ));

  // Gradients: 7x7 points over a square, mapped onto an octahedron.
  // The ring size 17*17 = 289 is close to a multiple of 49 (49*6 = 294)
    float n_ = 0.142857142857; // 1.0/7.0
    vec3  ns = n_ * D.wyz - D.xzx;

    vec4 j = p - 49.0 * floor(p * ns.z * ns.z);  //  mod(p,7*7)

    vec4 x_ = floor(j * ns.z);
    vec4 y_ = floor(j - 7.0 * x_ );    // mod(j,N)

    vec4 x = x_ *ns.x + ns.yyyy;
    vec4 y = y_ *ns.x + ns.yyyy;
    vec4 h = 1.0 - abs(x) - abs(y);

    vec4 b0 = vec4( x.xy, y.xy );
    vec4 b1 = vec4( x.zw, y.zw );

    //vec4 s0 = vec4(lessThan(b0,0.0))*2.0 - 1.0;
    //vec4 s1 = vec4(lessThan(b1,0.0))*2.0 - 1.0;
    vec4 s0 = floor(b0)*2.0 + 1.0;
    vec4 s1 = floor(b1)*2.0 + 1.0;
    vec4 sh = -step(h, vec4(0.0));

    vec4 a0 = b0.xzyw + s0.xzyw*sh.xxyy ;
    vec4 a1 = b1.xzyw + s1.xzyw*sh.zzww ;

    vec3 p0 = vec3(a0.xy,h.x);
    vec3 p1 = vec3(a0.zw,h.y);
    vec3 p2 = vec3(a1.xy,h.z);
    vec3 p3 = vec3(a1.zw,h.w);

  //Normalise gradients
    vec4 norm = taylorInvSqrt(vec4(dot(p0,p0), dot(p1,p1), dot(p2, p2), dot(p3,p3)));
    p0 *= norm.x;
    p1 *= norm.y;
    p2 *= norm.z;
    p3 *= norm.w;

  // Mix final noise value
    vec4 m = max(0.6 - vec4(dot(x0,x0), dot(x1,x1), dot(x2,x2), dot(x3,x3)), 0.0);
    m = m * m;
    return 42.0 * dot( m*m, vec4( dot(p0,x0), dot(p1,x1),
                                  dot(p2,x2), dot(p3,x3) ) );
    }

  // https://www.npmjs.com/package/glsl-curl-noise
  vec3 snoiseVec3( vec3 x ){

    float s  = snoise(vec3( x ));
    float s1 = snoise(vec3( x.y - 19.1 , x.z + 33.4 , x.x + 47.2 ));
    float s2 = snoise(vec3( x.z + 74.2 , x.x - 124.5 , x.y + 99.4 ));
    vec3 c = vec3( s , s1 , s2 );
    return c;

  }


  vec3 curlNoise( vec3 p ){

    const float e = .1;
    vec3 dx = vec3( e   , 0.0 , 0.0 );
    vec3 dy = vec3( 0.0 , e   , 0.0 );
    vec3 dz = vec3( 0.0 , 0.0 , e   );

    vec3 p_x0 = snoiseVec3( p - dx );
    vec3 p_x1 = snoiseVec3( p + dx );
    vec3 p_y0 = snoiseVec3( p - dy );
    vec3 p_y1 = snoiseVec3( p + dy );
    vec3 p_z0 = snoiseVec3( p - dz );
    vec3 p_z1 = snoiseVec3( p + dz );

    float x = p_y1.z - p_y0.z - p_z1.y + p_z0.y;
    float y = p_z1.x - p_z0.x - p_x1.z + p_x0.z;
    float z = p_x1.y - p_x0.y - p_y1.x + p_y0.x;

    const float divisor = 1.0 / ( 2.0 * e );
    return normalize( vec3( x , y , z ) * divisor );

  }

  const float speed = 2.;
  const float density = 0.007;
  const float ease = 0.02;

  void main () {
    vec2 uv = gl_FragCoord.st / size;
    vec4 velocity = texture2D(prevVelocityTexture, uv);
    vec3 prevPosition = texture2D(prevPositionTexture, uv).xyz;
    velocity.xyz += curlNoise(prevPosition * density) * speed;
    velocity.xyz *= velocity.w;
    if (velocity.w > 0.01) {
      velocity.w -= velocity.w * ease;
    } else {
      velocity.w = 1.;
    }
    gl_FragColor = velocity;
  }
</script>

<script type="x-shader/x-fragment" id="position">
  precision highp float;

  uniform vec2 size;
  uniform sampler2D prevPositionTexture;
  uniform sampler2D velocityTexture;

  void main () {
    vec2 uv = gl_FragCoord.st / size;
    vec4 prevPosition = texture2D(prevPositionTexture, uv);
    vec4 velocity = texture2D(velocityTexture, uv);

    vec3 position;
    if (velocity.w == 1.) {
      vec2 nPosition = uv * 2. - 1.;
      position = vec3(nPosition * size, 0.);
    } else {
      position = prevPosition.xyz + velocity.xyz;
    }

    gl_FragColor = vec4(position, prevPosition.w);
  }
</script>

<script type="x-shader/x-vertex" id="main-vs">
  attribute vec3 position;
  attribute vec3 normal;
  attribute vec2 instancedUv;

  uniform sampler2D positionTexture;
  uniform sampler2D velocityTexture;
  uniform mat4 mvpMatrix;
  uniform mat4 invMatrix;
  uniform vec3 lightDirection;
  uniform vec3 ambientColor;
  uniform vec3 eyeDirection;
  uniform float time;

  varying vec4 vColor;

  // https://github.com/yuichiroharai/glsl-y-rotate#readme
  mat3 rotateQ(vec3 axis, float rad) {
    float hr = rad / 2.0;
    float s = sin( hr );
    vec4 q = vec4(axis * s, cos( hr ));
    vec3 q2 = q.xyz + q.xyz;
    vec3 qq2 = q.xyz * q2;
    vec2 qx = q.xx * q2.yz;
    float qy = q.y * q2.z;
    vec3 qw = q.w * q2.xyz;

    return mat3(
        1.0 - (qq2.y + qq2.z),  qx.x - qw.z,            qx.y + qw.y,
        qx.x + qw.z,            1.0 - (qq2.x + qq2.z),  qy - qw.x,
        qx.y - qw.y,            qy + qw.x,              1.0 - (qq2.x + qq2.y)
    );
  }

  // https://github.com/mattdesl/glsl-random
  highp float random(vec2 co)
  {
      highp float a = 12.9898;
      highp float b = 78.233;
      highp float c = 43758.5453;
      highp float dt= dot(co.xy ,vec2(a,b));
      highp float sn= mod(dt,3.14);
      return fract(sin(sn) * c);
  }

  vec3 hsv(float h, float s, float v) {
    vec4 t = vec4(1., 2. / 3., 1. / 3., 3.);
    vec3 p = abs(fract(vec3(h) + t.xyz) * 6. - vec3(t.w));
    return v * mix(vec3(t.x), clamp(p - vec3(t.x), 0., 1.), s);
  }

  const float PI = 3.1415926;
  const float PI2 = PI * 2.;

  const float colorInterval = PI2 * 10.;
  const float scale = 2.;
  const float maxScaleRate = 1.4;
  const float rotationSpeed = 100.;
  const float minRotationSpeed = 0.1;

  void main () {
    vec3 modelPosition = position;
    vec4 instancedPosition = texture2D(positionTexture, instancedUv);
    float randomValue = instancedPosition.w;

    float velocity = texture2D(velocityTexture, instancedUv).w;
    float life = smoothstep(0.01, 0.04, velocity);

    float cScale = scale;
    cScale *= life;
    cScale *= mix(1., maxScaleRate, (instancedPosition.z - 1.) * 0.01);
    modelPosition *= 0.5 * cScale;

    vec3 axis = normalize(vec3(
      random(vec2(randomValue, 0.)),
      random(vec2(0., randomValue)),
      random(vec2(randomValue, 1.))
    ));
    float radian = PI2 * random(vec2(randomValue));
    radian += velocity * mix(minRotationSpeed, rotationSpeed, randomValue);
    mat3 rotate = rotateQ(axis, radian);
    modelPosition *= rotate;

    vec3 cNormal = normalize(normal);
    cNormal *= rotate;
    vec3 invLight = normalize(invMatrix * vec4(lightDirection, 0.)).rgb;
    vec3 invEye = normalize(invMatrix * vec4(eyeDirection, 0.)).rgb;
    vec3 halfLE = normalize(invLight + invEye);
    float diffuse = clamp(dot(cNormal, invLight), 0.1, 1.);
    float specular = pow(clamp(dot(cNormal, halfLE), 0., 1.), 50.);

    float colorNTime = mod(time * 0.001, colorInterval) / colorInterval;
    float alpha = 1.;
    vColor = vec4(hsv(colorNTime * PI2, 0.25 + 0.7 * colorNTime, 0.85 + 0.1 * colorNTime), alpha);
    vColor.rgb *= vec3(diffuse + specular);
    vColor.rgb += ambientColor;
    vColor.rgb *= mix(0.2, 1., clamp(((instancedPosition + 100.) / 200.).z, 0., 1.));
    vColor.rgb *= life;

    gl_Position = mvpMatrix * (vec4(modelPosition + instancedPosition.xyz, 1.));
  }
</script>

<script type="x-shader/x-fragment" id="main-fs">
  precision highp float;

  varying vec4 vColor;

  void main () {
    gl_FragColor = vColor;
  }
</script>

<script type="x-shader/x-fragment" id="texture">
  precision highp float;

  uniform vec2 resolution;
  uniform sampler2D texture;

  void main() {
    gl_FragColor = texture2D(texture, gl_FragCoord.st / resolution);
  }
</script>

            
          
!
            
              html,
body {
  height: 100%;
}
body {
  overflow: hidden;
  margin: 0;
}
canvas {
  width: 100%;
  height: 100%;
}

            
          
!
            
              // using original library https://github.com/ko-yelie/kgl

const width = 100
const height = 100

const sizeUniform = [width, height]
const particleUv = []

for (let j = 0; j < height; j++) {
  for (let i = 0; i < width; i++) {
    particleUv.push(i / (width - 1), 1 - j / (height - 1))
  }
}

const webgl = new Kgl({
  cameraPosition: [0, 0, 480.],
  fov: 50,
  programs: {
    resetVelocity: {
      fragmentShaderId: 'reset-velocity',
      isFloats: true,
    },
    resetPosition: {
      fragmentShaderId: 'reset-position',
      uniforms: {
        size: sizeUniform,
      },
      isFloats: true,
    },
    velocity: {
      fragmentShaderId: 'velocity',
      uniforms: {
        size: sizeUniform,
        prevVelocityTexture: 'framebuffer',
        prevPositionTexture: 'framebuffer',
      },
      isFloats: true,
    },
    position: {
      fragmentShaderId: 'position',
      uniforms: {
        size: sizeUniform,
        prevPositionTexture: 'framebuffer',
        velocityTexture: 'framebuffer',
      },
      isFloats: true,
    },
    main: {
      vertexShaderId: 'main-vs',
      fragmentShaderId: 'main-fs',
      attributes: {
        position: {
          value: [1, 1, -1, 1, 1, 1, 1, -1, 1, 1, -1, -1, -1, 1, 1, -1, 1, -1, -1, -1, -1, -1, -1, 1, -1, 1, 1, 1, 1, 1, 1, 1, -1, -1, 1, -1, -1, -1, -1, 1, -1, -1, 1, -1, 1, -1, -1, 1, 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, 1, -1, 1, 1, -1, 1, -1, -1, -1, -1, -1],
          size: 3,
        },
        normal: {
          value: [1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1],
          size: 3
        },
        indices: {
          value: [0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, 8, 9, 10, 8, 10, 11, 12, 13, 14, 12, 14, 15, 16, 17, 18, 16, 18, 19, 20, 21, 22, 20, 22, 23],
          isIndices: true
        },
      },
      instancedAttributes: {
        instancedUv: {
          value: particleUv,
          size: 2
        }
      },
      uniforms: {
        positionTexture: 'framebuffer',
        velocityTexture: 'framebuffer',
        time: 0,
      },
      isDepth: true,
      isTransparent: true,
    },
    texture: {
      fragmentShaderId: 'texture',
      uniforms: {
        texture: 'framebuffer'
      },
      clearedColor: [0, 0, 0, 1],
      isTransparent: true
    }
  },
  framebuffers: [
    'scene',
  ],
  framebufferFloats: {
    velocity0: {
      width,
      height
    },
    velocity1: {
      width,
      height
    },
    position0: {
      width,
      height
    },
    position1: {
      width,
      height
    }
  },
  isAutoStart: false
})

let loopCount = 0
let targetbufferIndex
let prevbufferIndex
let i

targetbufferIndex = loopCount++ % 2

{
  webgl.bindFramebuffer('velocity' + targetbufferIndex)
  webgl.programs['resetVelocity'].draw()
}

{
  webgl.bindFramebuffer('position' + targetbufferIndex)
  webgl.programs['resetPosition'].draw()
}

const draw = time => {
  targetbufferIndex = loopCount++ % 2
  prevbufferIndex = 1 - targetbufferIndex

  {
    webgl.bindFramebuffer('velocity' + targetbufferIndex)

    webgl.programs['velocity'].draw({
      prevVelocityTexture: 'velocity' + prevbufferIndex,
      prevPositionTexture: 'position' + prevbufferIndex,
    })
  }

  {
    webgl.bindFramebuffer('position' + targetbufferIndex)

    webgl.programs['position'].draw({
      prevPositionTexture: 'position' + prevbufferIndex,
      velocityTexture: 'velocity' + targetbufferIndex,
    })
  }

  {
    webgl.bindFramebuffer('scene')

    webgl.programs['main'].draw({
      positionTexture: 'position' + targetbufferIndex,
      velocityTexture: 'velocity' + targetbufferIndex,
      time,
    })
  }

  {
    webgl.unbindFramebuffer()

    webgl.programs['texture'].draw({
      texture: 'scene',
    })
  }

  requestAnimationFrame(draw)
}
requestAnimationFrame(draw)

            
          
!
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