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Revisions

  1. @patriciogonzalezvivo patriciogonzalezvivo renamed this gist Oct 18, 2014. 1 changed file with 28 additions and 28 deletions.
    56 changes: 28 additions & 28 deletions Noise.md → GLSL-Noise.md
    Original file line number Diff line number Diff line change
    @@ -1,31 +1,3 @@
    Articles:

    * Improving Noise, Ken Perlin <http://mrl.nyu.edu/~perlin/paper445.pdf>

    * Perlin Noise, Hugo Elias <http://freespace.virgin.net/hugo.elias/models/m_perlin.htm>

    * Implementation of Perlin Noise on GPU, Leena Kora <http://www.sci.utah.edu/~leenak/IndStudy_reportfall/Perlin%20Noise%20on%20GPU.html>

    * Implementing Improved Perlin Noise, Simon Green <http://http.developer.nvidia.com/GPUGems2/gpugems2_chapter26.html>

    * Perlin Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Perlin.php#.U7Fvs41dVhs>

    * Simplex Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Simplex.php#.U7FwI41dVhs>

    * Voronoise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Voronoi.php#.U7FwM41dVhs>

    * Voronoise, inigo quilez <http://iquilezles.org/www/articles/voronoise/voronoise.htm>

    * Voronoi Noise, <http://www.pixeleuphoria.com/node/34>

    * Mosaic Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Mosaic.php#.U7FwZo1dVhs>

    * Inigo Quilez <http://iquilezles.org/www/articles/morenoise/morenoise.htm>

    Examples:

    * Andrew Baldwin <http://thndl.com/?15>

    ## Generic 1,2,3 Noise

    ```
    @@ -1110,3 +1082,31 @@ float fbm( in vec2 p ){
    return f/0.9375;
    }
    ```

    Articles:

    * Improving Noise, Ken Perlin <http://mrl.nyu.edu/~perlin/paper445.pdf>

    * Perlin Noise, Hugo Elias <http://freespace.virgin.net/hugo.elias/models/m_perlin.htm>

    * Implementation of Perlin Noise on GPU, Leena Kora <http://www.sci.utah.edu/~leenak/IndStudy_reportfall/Perlin%20Noise%20on%20GPU.html>

    * Implementing Improved Perlin Noise, Simon Green <http://http.developer.nvidia.com/GPUGems2/gpugems2_chapter26.html>

    * Perlin Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Perlin.php#.U7Fvs41dVhs>

    * Simplex Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Simplex.php#.U7FwI41dVhs>

    * Voronoise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Voronoi.php#.U7FwM41dVhs>

    * Voronoise, inigo quilez <http://iquilezles.org/www/articles/voronoise/voronoise.htm>

    * Voronoi Noise, <http://www.pixeleuphoria.com/node/34>

    * Mosaic Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Mosaic.php#.U7FwZo1dVhs>

    * Inigo Quilez <http://iquilezles.org/www/articles/morenoise/morenoise.htm>

    Examples:

    * Andrew Baldwin <http://thndl.com/?15>
  2. @patriciogonzalezvivo patriciogonzalezvivo revised this gist Jul 2, 2014. 1 changed file with 0 additions and 2 deletions.
    2 changes: 0 additions & 2 deletions Noise.md
    Original file line number Diff line number Diff line change
    @@ -1,5 +1,3 @@
    # NOISE

    Articles:

    * Improving Noise, Ken Perlin <http://mrl.nyu.edu/~perlin/paper445.pdf>
  3. @patriciogonzalezvivo patriciogonzalezvivo revised this gist Jul 1, 2014. 1 changed file with 0 additions and 61 deletions.
    61 changes: 0 additions & 61 deletions Noise.md
    Original file line number Diff line number Diff line change
    @@ -145,67 +145,6 @@ float noise(vec3 x) {
    }
    ```


    ## IQ NOISES
    by inigo quilez


    ```
    // <https://www.shadertoy.com/view/MdX3Rr>
    // by inigo quilez
    //
    float hash(float n){ return fract(sin(n) * 43758.5453123);}
    float noise(vec2 x){
    vec2 p = floor(x);
    vec2 f = fract(x);
    f = f*f*(3.0-2.0*f);
    float n = p.x + p.y*57.0;
    float res = mix(mix( hash(n+ 0.0), hash(n+ 1.0),f.x),
    mix( hash(n+ 57.0), hash(n+ 58.0),f.x),f.y);
    return res;
    }
    ```

    ```
    // <https://www.shadertoy.com/view/XslGRr>
    // by inigo quilez
    //
    float hash(float n){ return fract(sin(n) * 43758.5453123);}
    float noise(vec3 x){
    vec3 p = floor(x);
    vec3 f = fract(x);
    f = f*f*(3.0-2.0*f);
    float n = p.x + p.y*157.0 + 113.0*p.z;
    return mix(mix(mix( hash(n+ 0.0), hash(n+ 1.0),f.x),
    mix( hash(n+157.0), hash(n+158.0),f.x),f.y),
    mix(mix( hash(n+113.0), hash(n+114.0),f.x),
    mix( hash(n+270.0), hash(n+271.0),f.x),f.y),f.z);
    }
    ```

    ```
    // <https://www.shadertoy.com/view/MdX3Rr>
    // by inigo quilez
    //
    float hash(float n){ return fract(sin(n) * 43758.5453123);}
    vec3 noised( vec2 x ){
    vec2 p = floor(x);
    vec2 f = fract(x);
    vec2 u = f*f*(3.0-2.0*f);
    float n = p.x + p.y*57.0;
    float a = hash(n+ 0.0);
    float b = hash(n+ 1.0);
    float c = hash(n+ 57.0);
    float d = hash(n+ 58.0);
    return vec3(a+(b-a)*u.x+(c-a)*u.y+(a-b-c+d)*u.x*u.y,
    30.0*f*f*(f*(f-2.0)+1.0)*(vec2(b-a,c-a)+(a-b-c+d)*u.yx));
    }
    ```

    ## Perlin Noise

    ```
  4. @patriciogonzalezvivo patriciogonzalezvivo revised this gist Jul 1, 2014. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion Noise.md
    Original file line number Diff line number Diff line change
    @@ -1162,7 +1162,7 @@ float fbm(vec3 x) {
    // <https://www.shadertoy.com/view/MdX3Rr>
    // by inigo quilez
    //
    const mat2 m2 = mat2(1.6,-1.2,1.2,1.6);
    const mat2 m2 = mat2(0.8,-0.6,0.6,0.8);
    float fbm( in vec2 p ){
    float f = 0.0;
    f += 0.5000*noise( p ); p = m2*p*2.02;
  5. @patriciogonzalezvivo patriciogonzalezvivo revised this gist Jun 30, 2014. 1 changed file with 0 additions and 78 deletions.
    78 changes: 0 additions & 78 deletions Noise.md
    Original file line number Diff line number Diff line change
    @@ -970,84 +970,6 @@ float snoiseFractal(vec3 m) {
    ```

    ## NOISE SubTypes

    ```
    // Blur noise
    //
    float smooth_noise(vec2 pos){
    return ( noise(pos + vec2(1,1)) + noise(pos + vec2(1,1)) + noise(pos + vec2(1,1)) + noise(pos + vec2(1,1)) ) / 16.0
    + ( noise(pos + vec2(1,0)) + noise(pos + vec2(-1,0)) + noise(pos + vec2(0,1)) + noise(pos + vec2(0,-1)) ) / 8.0
    + noise(pos) / 4.0;
    }
    // Linear interpolation
    //
    float interpolate_noise(vec2 pos){
    float a, b, c, d;
    a = smooth_noise(floor(pos));
    b = smooth_noise(vec2(floor(pos.x+1.0), floor(pos.y)));
    c = smooth_noise(vec2(floor(pos.x), floor(pos.y+1.0)));
    d = smooth_noise(vec2(floor(pos.x+1.0), floor(pos.y+1.0)));
    a = mix(a, b, fract(pos.x));
    b = mix(c, d, fract(pos.x));
    a = mix(a, b, fract(pos.y));
    return a;
    }
    ```

    ```
    // Noise Flow <https://www.shadertoy.com/view/lslXRS>
    // by nimitz (stormoid.com) (twitter: @stormoid)
    //
    mat2 makem2(in float theta){float c = cos(theta);float s = sin(theta);return mat2(c,-s,s,c);}
    vec2 gradn(vec2 p){
    float ep = .09;
    float gradx = noise(vec2(p.x+ep,p.y))-noise(vec2(p.x-ep,p.y));
    float grady = noise(vec2(p.x,p.y+ep))-noise(vec2(p.x,p.y-ep));
    return vec2(gradx,grady);
    }
    float flow(vec2 p){
    float z=2.;
    float rz = 0.;
    vec2 bp = p;
    for (float i= 1.;i < 7.;i++ ){
    //primary flow speed
    p += time*1.5;
    //secondary flow speed (speed of the perceived flow)
    bp += time*2.;
    //displacement field (try changing time multiplier)
    vec2 gr = gradn(i*p*.34+time*1.);
    //rotation of the displacement field
    gr*=makem2(time*10.-(0.05*p.x+0.03*p.y)*40.);
    //displace the system
    p += gr*.5;
    //add noise octave
    rz+= (sin(noise(p)*7.)*0.5+0.5)/z;
    //blend factor (blending displaced system with base system)
    //you could call this advection factor (.5 being low, .95 being high)
    p = mix(bp,p,.8);
    //intensity scaling
    z *= 1.4;
    //octave scaling
    p *= 2.;
    bp *= 1.9;
    }
    return rz;
    }
    ```

    ### NormalMap Noise

  6. @patriciogonzalezvivo patriciogonzalezvivo revised this gist Jun 30, 2014. 1 changed file with 1 addition and 0 deletions.
    1 change: 1 addition & 0 deletions Noise.md
    Original file line number Diff line number Diff line change
    @@ -698,6 +698,7 @@ float cnoise(vec4 P, vec4 rep){
    float n_xyzw = mix(n_yzw.x, n_yzw.y, fade_xyzw.x);
    return 2.2 * n_xyzw;
    }
    ```

    ### [Simplex Noise](http://en.wikipedia.org/wiki/Simplex_noise)

  7. @patriciogonzalezvivo patriciogonzalezvivo created this gist Jun 30, 2014.
    1,252 changes: 1,252 additions & 0 deletions Noise.md
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,1252 @@
    # NOISE

    Articles:

    * Improving Noise, Ken Perlin <http://mrl.nyu.edu/~perlin/paper445.pdf>

    * Perlin Noise, Hugo Elias <http://freespace.virgin.net/hugo.elias/models/m_perlin.htm>

    * Implementation of Perlin Noise on GPU, Leena Kora <http://www.sci.utah.edu/~leenak/IndStudy_reportfall/Perlin%20Noise%20on%20GPU.html>

    * Implementing Improved Perlin Noise, Simon Green <http://http.developer.nvidia.com/GPUGems2/gpugems2_chapter26.html>

    * Perlin Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Perlin.php#.U7Fvs41dVhs>

    * Simplex Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Simplex.php#.U7FwI41dVhs>

    * Voronoise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Voronoi.php#.U7FwM41dVhs>

    * Voronoise, inigo quilez <http://iquilezles.org/www/articles/voronoise/voronoise.htm>

    * Voronoi Noise, <http://www.pixeleuphoria.com/node/34>

    * Mosaic Noise <http://mines.lumpylumpy.com/Electronics/Computers/Software/Cpp/Graphics/Bitmap/Textures/Noise/Mosaic.php#.U7FwZo1dVhs>

    * Inigo Quilez <http://iquilezles.org/www/articles/morenoise/morenoise.htm>

    Examples:

    * Andrew Baldwin <http://thndl.com/?15>

    ## Generic 1,2,3 Noise

    ```
    float rand(float n){return fract(sin(n) * 43758.5453123);}
    float noise(float p){
    float fl = floor(p);
    float fc = fract(p);
    return mix(rand(fl), rand(fl + 1.0), fc);
    }
    float noise(vec2 n) {
    const vec2 d = vec2(0.0, 1.0);
    vec2 b = floor(n), f = smoothstep(vec2(0.0), vec2(1.0), fract(n));
    return mix(mix(rand(b), rand(b + d.yx), f.x), mix(rand(b + d.xy), rand(b + d.yy), f.x), f.y);
    }
    ```

    ```
    float rand(vec2 n) {
    return fract(sin(dot(n, vec2(12.9898, 4.1414))) * 43758.5453);
    }
    float noise(vec2 p){
    vec2 ip = floor(p);
    vec2 u = fract(p);
    u = u*u*(3.0-2.0*u);
    float res = mix(
    mix(rand(ip),rand(ip+vec2(1.0,0.0)),u.x),
    mix(rand(ip+vec2(0.0,1.0)),rand(ip+vec2(1.0,1.0)),u.x),u.y);
    return res*res;
    }
    ```

    ```
    float mod289(float 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 perm(vec4 x){return mod289(((x * 34.0) + 1.0) * x);}
    float noise(vec3 p){
    vec3 a = floor(p);
    vec3 d = p - a;
    d = d * d * (3.0 - 2.0 * d);
    vec4 b = a.xxyy + vec4(0.0, 1.0, 0.0, 1.0);
    vec4 k1 = perm(b.xyxy);
    vec4 k2 = perm(k1.xyxy + b.zzww);
    vec4 c = k2 + a.zzzz;
    vec4 k3 = perm(c);
    vec4 k4 = perm(c + 1.0);
    vec4 o1 = fract(k3 * (1.0 / 41.0));
    vec4 o2 = fract(k4 * (1.0 / 41.0));
    vec4 o3 = o2 * d.z + o1 * (1.0 - d.z);
    vec2 o4 = o3.yw * d.x + o3.xz * (1.0 - d.x);
    return o4.y * d.y + o4.x * (1.0 - d.y);
    }
    ```

    ```
    // <https://www.shadertoy.com/view/4dS3Wd>
    // By Morgan McGuire @morgan3d, http://graphicscodex.com
    //
    float hash(float n) { return fract(sin(n) * 1e4); }
    float hash(vec2 p) { return fract(1e4 * sin(17.0 * p.x + p.y * 0.1) * (0.1 + abs(sin(p.y * 13.0 + p.x)))); }
    float noise(float x) {
    float i = floor(x);
    float f = fract(x);
    float u = f * f * (3.0 - 2.0 * f);
    return mix(hash(i), hash(i + 1.0), u);
    }
    float noise(vec2 x) {
    vec2 i = floor(x);
    vec2 f = fract(x);
    // Four corners in 2D of a tile
    float a = hash(i);
    float b = hash(i + vec2(1.0, 0.0));
    float c = hash(i + vec2(0.0, 1.0));
    float d = hash(i + vec2(1.0, 1.0));
    // Simple 2D lerp using smoothstep envelope between the values.
    // return vec3(mix(mix(a, b, smoothstep(0.0, 1.0, f.x)),
    // mix(c, d, smoothstep(0.0, 1.0, f.x)),
    // smoothstep(0.0, 1.0, f.y)));
    // Same code, with the clamps in smoothstep and common subexpressions
    // optimized away.
    vec2 u = f * f * (3.0 - 2.0 * f);
    return mix(a, b, u.x) + (c - a) * u.y * (1.0 - u.x) + (d - b) * u.x * u.y;
    }
    // This one has non-ideal tiling properties that I'm still tuning
    float noise(vec3 x) {
    const vec3 step = vec3(110, 241, 171);
    vec3 i = floor(x);
    vec3 f = fract(x);
    // For performance, compute the base input to a 1D hash from the integer part of the argument and the
    // incremental change to the 1D based on the 3D -> 1D wrapping
    float n = dot(i, step);
    vec3 u = f * f * (3.0 - 2.0 * f);
    return mix(mix(mix( hash(n + dot(step, vec3(0, 0, 0))), hash(n + dot(step, vec3(1, 0, 0))), u.x),
    mix( hash(n + dot(step, vec3(0, 1, 0))), hash(n + dot(step, vec3(1, 1, 0))), u.x), u.y),
    mix(mix( hash(n + dot(step, vec3(0, 0, 1))), hash(n + dot(step, vec3(1, 0, 1))), u.x),
    mix( hash(n + dot(step, vec3(0, 1, 1))), hash(n + dot(step, vec3(1, 1, 1))), u.x), u.y), u.z);
    }
    ```


    ## IQ NOISES
    by inigo quilez


    ```
    // <https://www.shadertoy.com/view/MdX3Rr>
    // by inigo quilez
    //
    float hash(float n){ return fract(sin(n) * 43758.5453123);}
    float noise(vec2 x){
    vec2 p = floor(x);
    vec2 f = fract(x);
    f = f*f*(3.0-2.0*f);
    float n = p.x + p.y*57.0;
    float res = mix(mix( hash(n+ 0.0), hash(n+ 1.0),f.x),
    mix( hash(n+ 57.0), hash(n+ 58.0),f.x),f.y);
    return res;
    }
    ```

    ```
    // <https://www.shadertoy.com/view/XslGRr>
    // by inigo quilez
    //
    float hash(float n){ return fract(sin(n) * 43758.5453123);}
    float noise(vec3 x){
    vec3 p = floor(x);
    vec3 f = fract(x);
    f = f*f*(3.0-2.0*f);
    float n = p.x + p.y*157.0 + 113.0*p.z;
    return mix(mix(mix( hash(n+ 0.0), hash(n+ 1.0),f.x),
    mix( hash(n+157.0), hash(n+158.0),f.x),f.y),
    mix(mix( hash(n+113.0), hash(n+114.0),f.x),
    mix( hash(n+270.0), hash(n+271.0),f.x),f.y),f.z);
    }
    ```

    ```
    // <https://www.shadertoy.com/view/MdX3Rr>
    // by inigo quilez
    //
    float hash(float n){ return fract(sin(n) * 43758.5453123);}
    vec3 noised( vec2 x ){
    vec2 p = floor(x);
    vec2 f = fract(x);
    vec2 u = f*f*(3.0-2.0*f);
    float n = p.x + p.y*57.0;
    float a = hash(n+ 0.0);
    float b = hash(n+ 1.0);
    float c = hash(n+ 57.0);
    float d = hash(n+ 58.0);
    return vec3(a+(b-a)*u.x+(c-a)*u.y+(a-b-c+d)*u.x*u.y,
    30.0*f*f*(f*(f-2.0)+1.0)*(vec2(b-a,c-a)+(a-b-c+d)*u.yx));
    }
    ```

    ## Perlin Noise

    ```
    float rand(vec2 c){
    return fract(sin(dot(c.xy ,vec2(12.9898,78.233))) * 43758.5453);
    }
    float noise(vec2 p, float freq ){
    float unit = screenWidth/freq;
    vec2 ij = floor(p/unit);
    vec2 xy = mod(p,unit)/unit;
    //xy = 3.*xy*xy-2.*xy*xy*xy;
    xy = .5*(1.-cos(PI*xy));
    float a = rand((ij+vec2(0.,0.)));
    float b = rand((ij+vec2(1.,0.)));
    float c = rand((ij+vec2(0.,1.)));
    float d = rand((ij+vec2(1.,1.)));
    float x1 = mix(a, b, xy.x);
    float x2 = mix(c, d, xy.x);
    return mix(x1, x2, xy.y);
    }
    float pNoise(vec2 p, int res){
    float persistance = .5;
    float n = 0.;
    float normK = 0.;
    float f = 4.;
    float amp = 1.;
    int iCount = 0;
    for (int i = 0; i<50; i++){
    n+=amp*noise(p, f);
    f*=2.;
    normK+=amp;
    amp*=persistance;
    if (iCount == res) break;
    iCount++;
    }
    float nf = n/normK;
    return nf*nf*nf*nf;
    }
    ```

    ```
    #define M_PI 3.14159265358979323846
    float rand(vec2 co){return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453);}
    float rand (vec2 co, float l) {return rand(vec2(rand(co), l));}
    float rand (vec2 co, float l, float t) {return rand(vec2(rand(co, l), t));}
    float perlin(vec2 p, float dim, float time) {
    vec2 pos = floor(p * dim);
    vec2 posx = pos + vec2(1.0, 0.0);
    vec2 posy = pos + vec2(0.0, 1.0);
    vec2 posxy = pos + vec2(1.0);
    float c = rand(pos, dim, time);
    float cx = rand(posx, dim, time);
    float cy = rand(posy, dim, time);
    float cxy = rand(posxy, dim, time);
    vec2 d = fract(p * dim);
    d = -0.5 * cos(d * M_PI) + 0.5;
    float ccx = mix(c, cx, d.x);
    float cycxy = mix(cy, cxy, d.x);
    float center = mix(ccx, cycxy, d.y);
    return center * 2.0 - 1.0;
    }
    // p must be normalized!
    float perlin(vec2 p, float dim) {
    /*vec2 pos = floor(p * dim);
    vec2 posx = pos + vec2(1.0, 0.0);
    vec2 posy = pos + vec2(0.0, 1.0);
    vec2 posxy = pos + vec2(1.0);
    // For exclusively black/white noise
    /*float c = step(rand(pos, dim), 0.5);
    float cx = step(rand(posx, dim), 0.5);
    float cy = step(rand(posy, dim), 0.5);
    float cxy = step(rand(posxy, dim), 0.5);*/
    /*float c = rand(pos, dim);
    float cx = rand(posx, dim);
    float cy = rand(posy, dim);
    float cxy = rand(posxy, dim);
    vec2 d = fract(p * dim);
    d = -0.5 * cos(d * M_PI) + 0.5;
    float ccx = mix(c, cx, d.x);
    float cycxy = mix(cy, cxy, d.x);
    float center = mix(ccx, cycxy, d.y);
    return center * 2.0 - 1.0;*/
    return perlin(p, dim, 0.0);
    }
    ```

    ## Classic Perlin Noise

    ```
    // Classic Perlin 2D Noise
    // by Stefan Gustavson
    //
    vec2 fade(vec2 t) {return t*t*t*(t*(t*6.0-15.0)+10.0);}
    float cnoise(vec2 P){
    vec4 Pi = floor(P.xyxy) + vec4(0.0, 0.0, 1.0, 1.0);
    vec4 Pf = fract(P.xyxy) - vec4(0.0, 0.0, 1.0, 1.0);
    Pi = mod(Pi, 289.0); // To avoid truncation effects in permutation
    vec4 ix = Pi.xzxz;
    vec4 iy = Pi.yyww;
    vec4 fx = Pf.xzxz;
    vec4 fy = Pf.yyww;
    vec4 i = permute(permute(ix) + iy);
    vec4 gx = 2.0 * fract(i * 0.0243902439) - 1.0; // 1/41 = 0.024...
    vec4 gy = abs(gx) - 0.5;
    vec4 tx = floor(gx + 0.5);
    gx = gx - tx;
    vec2 g00 = vec2(gx.x,gy.x);
    vec2 g10 = vec2(gx.y,gy.y);
    vec2 g01 = vec2(gx.z,gy.z);
    vec2 g11 = vec2(gx.w,gy.w);
    vec4 norm = 1.79284291400159 - 0.85373472095314 *
    vec4(dot(g00, g00), dot(g01, g01), dot(g10, g10), dot(g11, g11));
    g00 *= norm.x;
    g01 *= norm.y;
    g10 *= norm.z;
    g11 *= norm.w;
    float n00 = dot(g00, vec2(fx.x, fy.x));
    float n10 = dot(g10, vec2(fx.y, fy.y));
    float n01 = dot(g01, vec2(fx.z, fy.z));
    float n11 = dot(g11, vec2(fx.w, fy.w));
    vec2 fade_xy = fade(Pf.xy);
    vec2 n_x = mix(vec2(n00, n01), vec2(n10, n11), fade_xy.x);
    float n_xy = mix(n_x.x, n_x.y, fade_xy.y);
    return 2.3 * n_xy;
    }
    ```

    ```
    // Classic Perlin 3D Noise
    // by Stefan Gustavson
    //
    vec4 permute(vec4 x){return mod(((x*34.0)+1.0)*x, 289.0);}
    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);}
    float cnoise(vec3 P){
    vec3 Pi0 = floor(P); // Integer part for indexing
    vec3 Pi1 = Pi0 + vec3(1.0); // Integer part + 1
    Pi0 = mod(Pi0, 289.0);
    Pi1 = mod(Pi1, 289.0);
    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 / 7.0;
    vec4 gy0 = fract(floor(gx0) / 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 / 7.0;
    vec4 gy1 = fract(floor(gx1) / 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;
    }
    ```

    ```
    // Classic Perlin 3D Noise
    // by Stefan Gustavson
    //
    vec4 permute(vec4 x){return mod(((x*34.0)+1.0)*x, 289.0);}
    vec4 taylorInvSqrt(vec4 r){return 1.79284291400159 - 0.85373472095314 * r;}
    vec4 fade(vec4 t) {return t*t*t*(t*(t*6.0-15.0)+10.0);}
    float cnoise(vec4 P){
    vec4 Pi0 = floor(P); // Integer part for indexing
    vec4 Pi1 = Pi0 + 1.0; // Integer part + 1
    Pi0 = mod(Pi0, 289.0);
    Pi1 = mod(Pi1, 289.0);
    vec4 Pf0 = fract(P); // Fractional part for interpolation
    vec4 Pf1 = Pf0 - 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 = vec4(Pi0.zzzz);
    vec4 iz1 = vec4(Pi1.zzzz);
    vec4 iw0 = vec4(Pi0.wwww);
    vec4 iw1 = vec4(Pi1.wwww);
    vec4 ixy = permute(permute(ix) + iy);
    vec4 ixy0 = permute(ixy + iz0);
    vec4 ixy1 = permute(ixy + iz1);
    vec4 ixy00 = permute(ixy0 + iw0);
    vec4 ixy01 = permute(ixy0 + iw1);
    vec4 ixy10 = permute(ixy1 + iw0);
    vec4 ixy11 = permute(ixy1 + iw1);
    vec4 gx00 = ixy00 / 7.0;
    vec4 gy00 = floor(gx00) / 7.0;
    vec4 gz00 = floor(gy00) / 6.0;
    gx00 = fract(gx00) - 0.5;
    gy00 = fract(gy00) - 0.5;
    gz00 = fract(gz00) - 0.5;
    vec4 gw00 = vec4(0.75) - abs(gx00) - abs(gy00) - abs(gz00);
    vec4 sw00 = step(gw00, vec4(0.0));
    gx00 -= sw00 * (step(0.0, gx00) - 0.5);
    gy00 -= sw00 * (step(0.0, gy00) - 0.5);
    vec4 gx01 = ixy01 / 7.0;
    vec4 gy01 = floor(gx01) / 7.0;
    vec4 gz01 = floor(gy01) / 6.0;
    gx01 = fract(gx01) - 0.5;
    gy01 = fract(gy01) - 0.5;
    gz01 = fract(gz01) - 0.5;
    vec4 gw01 = vec4(0.75) - abs(gx01) - abs(gy01) - abs(gz01);
    vec4 sw01 = step(gw01, vec4(0.0));
    gx01 -= sw01 * (step(0.0, gx01) - 0.5);
    gy01 -= sw01 * (step(0.0, gy01) - 0.5);
    vec4 gx10 = ixy10 / 7.0;
    vec4 gy10 = floor(gx10) / 7.0;
    vec4 gz10 = floor(gy10) / 6.0;
    gx10 = fract(gx10) - 0.5;
    gy10 = fract(gy10) - 0.5;
    gz10 = fract(gz10) - 0.5;
    vec4 gw10 = vec4(0.75) - abs(gx10) - abs(gy10) - abs(gz10);
    vec4 sw10 = step(gw10, vec4(0.0));
    gx10 -= sw10 * (step(0.0, gx10) - 0.5);
    gy10 -= sw10 * (step(0.0, gy10) - 0.5);
    vec4 gx11 = ixy11 / 7.0;
    vec4 gy11 = floor(gx11) / 7.0;
    vec4 gz11 = floor(gy11) / 6.0;
    gx11 = fract(gx11) - 0.5;
    gy11 = fract(gy11) - 0.5;
    gz11 = fract(gz11) - 0.5;
    vec4 gw11 = vec4(0.75) - abs(gx11) - abs(gy11) - abs(gz11);
    vec4 sw11 = step(gw11, vec4(0.0));
    gx11 -= sw11 * (step(0.0, gx11) - 0.5);
    gy11 -= sw11 * (step(0.0, gy11) - 0.5);
    vec4 g0000 = vec4(gx00.x,gy00.x,gz00.x,gw00.x);
    vec4 g1000 = vec4(gx00.y,gy00.y,gz00.y,gw00.y);
    vec4 g0100 = vec4(gx00.z,gy00.z,gz00.z,gw00.z);
    vec4 g1100 = vec4(gx00.w,gy00.w,gz00.w,gw00.w);
    vec4 g0010 = vec4(gx10.x,gy10.x,gz10.x,gw10.x);
    vec4 g1010 = vec4(gx10.y,gy10.y,gz10.y,gw10.y);
    vec4 g0110 = vec4(gx10.z,gy10.z,gz10.z,gw10.z);
    vec4 g1110 = vec4(gx10.w,gy10.w,gz10.w,gw10.w);
    vec4 g0001 = vec4(gx01.x,gy01.x,gz01.x,gw01.x);
    vec4 g1001 = vec4(gx01.y,gy01.y,gz01.y,gw01.y);
    vec4 g0101 = vec4(gx01.z,gy01.z,gz01.z,gw01.z);
    vec4 g1101 = vec4(gx01.w,gy01.w,gz01.w,gw01.w);
    vec4 g0011 = vec4(gx11.x,gy11.x,gz11.x,gw11.x);
    vec4 g1011 = vec4(gx11.y,gy11.y,gz11.y,gw11.y);
    vec4 g0111 = vec4(gx11.z,gy11.z,gz11.z,gw11.z);
    vec4 g1111 = vec4(gx11.w,gy11.w,gz11.w,gw11.w);
    vec4 norm00 = taylorInvSqrt(vec4(dot(g0000, g0000), dot(g0100, g0100), dot(g1000, g1000), dot(g1100, g1100)));
    g0000 *= norm00.x;
    g0100 *= norm00.y;
    g1000 *= norm00.z;
    g1100 *= norm00.w;
    vec4 norm01 = taylorInvSqrt(vec4(dot(g0001, g0001), dot(g0101, g0101), dot(g1001, g1001), dot(g1101, g1101)));
    g0001 *= norm01.x;
    g0101 *= norm01.y;
    g1001 *= norm01.z;
    g1101 *= norm01.w;
    vec4 norm10 = taylorInvSqrt(vec4(dot(g0010, g0010), dot(g0110, g0110), dot(g1010, g1010), dot(g1110, g1110)));
    g0010 *= norm10.x;
    g0110 *= norm10.y;
    g1010 *= norm10.z;
    g1110 *= norm10.w;
    vec4 norm11 = taylorInvSqrt(vec4(dot(g0011, g0011), dot(g0111, g0111), dot(g1011, g1011), dot(g1111, g1111)));
    g0011 *= norm11.x;
    g0111 *= norm11.y;
    g1011 *= norm11.z;
    g1111 *= norm11.w;
    float n0000 = dot(g0000, Pf0);
    float n1000 = dot(g1000, vec4(Pf1.x, Pf0.yzw));
    float n0100 = dot(g0100, vec4(Pf0.x, Pf1.y, Pf0.zw));
    float n1100 = dot(g1100, vec4(Pf1.xy, Pf0.zw));
    float n0010 = dot(g0010, vec4(Pf0.xy, Pf1.z, Pf0.w));
    float n1010 = dot(g1010, vec4(Pf1.x, Pf0.y, Pf1.z, Pf0.w));
    float n0110 = dot(g0110, vec4(Pf0.x, Pf1.yz, Pf0.w));
    float n1110 = dot(g1110, vec4(Pf1.xyz, Pf0.w));
    float n0001 = dot(g0001, vec4(Pf0.xyz, Pf1.w));
    float n1001 = dot(g1001, vec4(Pf1.x, Pf0.yz, Pf1.w));
    float n0101 = dot(g0101, vec4(Pf0.x, Pf1.y, Pf0.z, Pf1.w));
    float n1101 = dot(g1101, vec4(Pf1.xy, Pf0.z, Pf1.w));
    float n0011 = dot(g0011, vec4(Pf0.xy, Pf1.zw));
    float n1011 = dot(g1011, vec4(Pf1.x, Pf0.y, Pf1.zw));
    float n0111 = dot(g0111, vec4(Pf0.x, Pf1.yzw));
    float n1111 = dot(g1111, Pf1);
    vec4 fade_xyzw = fade(Pf0);
    vec4 n_0w = mix(vec4(n0000, n1000, n0100, n1100), vec4(n0001, n1001, n0101, n1101), fade_xyzw.w);
    vec4 n_1w = mix(vec4(n0010, n1010, n0110, n1110), vec4(n0011, n1011, n0111, n1111), fade_xyzw.w);
    vec4 n_zw = mix(n_0w, n_1w, fade_xyzw.z);
    vec2 n_yzw = mix(n_zw.xy, n_zw.zw, fade_xyzw.y);
    float n_xyzw = mix(n_yzw.x, n_yzw.y, fade_xyzw.x);
    return 2.2 * n_xyzw;
    }
    // Classic Perlin noise, periodic version
    float cnoise(vec4 P, vec4 rep){
    vec4 Pi0 = mod(floor(P), rep); // Integer part modulo rep
    vec4 Pi1 = mod(Pi0 + 1.0, rep); // Integer part + 1 mod rep
    vec4 Pf0 = fract(P); // Fractional part for interpolation
    vec4 Pf1 = Pf0 - 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 = vec4(Pi0.zzzz);
    vec4 iz1 = vec4(Pi1.zzzz);
    vec4 iw0 = vec4(Pi0.wwww);
    vec4 iw1 = vec4(Pi1.wwww);
    vec4 ixy = permute(permute(ix) + iy);
    vec4 ixy0 = permute(ixy + iz0);
    vec4 ixy1 = permute(ixy + iz1);
    vec4 ixy00 = permute(ixy0 + iw0);
    vec4 ixy01 = permute(ixy0 + iw1);
    vec4 ixy10 = permute(ixy1 + iw0);
    vec4 ixy11 = permute(ixy1 + iw1);
    vec4 gx00 = ixy00 / 7.0;
    vec4 gy00 = floor(gx00) / 7.0;
    vec4 gz00 = floor(gy00) / 6.0;
    gx00 = fract(gx00) - 0.5;
    gy00 = fract(gy00) - 0.5;
    gz00 = fract(gz00) - 0.5;
    vec4 gw00 = vec4(0.75) - abs(gx00) - abs(gy00) - abs(gz00);
    vec4 sw00 = step(gw00, vec4(0.0));
    gx00 -= sw00 * (step(0.0, gx00) - 0.5);
    gy00 -= sw00 * (step(0.0, gy00) - 0.5);
    vec4 gx01 = ixy01 / 7.0;
    vec4 gy01 = floor(gx01) / 7.0;
    vec4 gz01 = floor(gy01) / 6.0;
    gx01 = fract(gx01) - 0.5;
    gy01 = fract(gy01) - 0.5;
    gz01 = fract(gz01) - 0.5;
    vec4 gw01 = vec4(0.75) - abs(gx01) - abs(gy01) - abs(gz01);
    vec4 sw01 = step(gw01, vec4(0.0));
    gx01 -= sw01 * (step(0.0, gx01) - 0.5);
    gy01 -= sw01 * (step(0.0, gy01) - 0.5);
    vec4 gx10 = ixy10 / 7.0;
    vec4 gy10 = floor(gx10) / 7.0;
    vec4 gz10 = floor(gy10) / 6.0;
    gx10 = fract(gx10) - 0.5;
    gy10 = fract(gy10) - 0.5;
    gz10 = fract(gz10) - 0.5;
    vec4 gw10 = vec4(0.75) - abs(gx10) - abs(gy10) - abs(gz10);
    vec4 sw10 = step(gw10, vec4(0.0));
    gx10 -= sw10 * (step(0.0, gx10) - 0.5);
    gy10 -= sw10 * (step(0.0, gy10) - 0.5);
    vec4 gx11 = ixy11 / 7.0;
    vec4 gy11 = floor(gx11) / 7.0;
    vec4 gz11 = floor(gy11) / 6.0;
    gx11 = fract(gx11) - 0.5;
    gy11 = fract(gy11) - 0.5;
    gz11 = fract(gz11) - 0.5;
    vec4 gw11 = vec4(0.75) - abs(gx11) - abs(gy11) - abs(gz11);
    vec4 sw11 = step(gw11, vec4(0.0));
    gx11 -= sw11 * (step(0.0, gx11) - 0.5);
    gy11 -= sw11 * (step(0.0, gy11) - 0.5);
    vec4 g0000 = vec4(gx00.x,gy00.x,gz00.x,gw00.x);
    vec4 g1000 = vec4(gx00.y,gy00.y,gz00.y,gw00.y);
    vec4 g0100 = vec4(gx00.z,gy00.z,gz00.z,gw00.z);
    vec4 g1100 = vec4(gx00.w,gy00.w,gz00.w,gw00.w);
    vec4 g0010 = vec4(gx10.x,gy10.x,gz10.x,gw10.x);
    vec4 g1010 = vec4(gx10.y,gy10.y,gz10.y,gw10.y);
    vec4 g0110 = vec4(gx10.z,gy10.z,gz10.z,gw10.z);
    vec4 g1110 = vec4(gx10.w,gy10.w,gz10.w,gw10.w);
    vec4 g0001 = vec4(gx01.x,gy01.x,gz01.x,gw01.x);
    vec4 g1001 = vec4(gx01.y,gy01.y,gz01.y,gw01.y);
    vec4 g0101 = vec4(gx01.z,gy01.z,gz01.z,gw01.z);
    vec4 g1101 = vec4(gx01.w,gy01.w,gz01.w,gw01.w);
    vec4 g0011 = vec4(gx11.x,gy11.x,gz11.x,gw11.x);
    vec4 g1011 = vec4(gx11.y,gy11.y,gz11.y,gw11.y);
    vec4 g0111 = vec4(gx11.z,gy11.z,gz11.z,gw11.z);
    vec4 g1111 = vec4(gx11.w,gy11.w,gz11.w,gw11.w);
    vec4 norm00 = taylorInvSqrt(vec4(dot(g0000, g0000), dot(g0100, g0100), dot(g1000, g1000), dot(g1100, g1100)));
    g0000 *= norm00.x;
    g0100 *= norm00.y;
    g1000 *= norm00.z;
    g1100 *= norm00.w;
    vec4 norm01 = taylorInvSqrt(vec4(dot(g0001, g0001), dot(g0101, g0101), dot(g1001, g1001), dot(g1101, g1101)));
    g0001 *= norm01.x;
    g0101 *= norm01.y;
    g1001 *= norm01.z;
    g1101 *= norm01.w;
    vec4 norm10 = taylorInvSqrt(vec4(dot(g0010, g0010), dot(g0110, g0110), dot(g1010, g1010), dot(g1110, g1110)));
    g0010 *= norm10.x;
    g0110 *= norm10.y;
    g1010 *= norm10.z;
    g1110 *= norm10.w;
    vec4 norm11 = taylorInvSqrt(vec4(dot(g0011, g0011), dot(g0111, g0111), dot(g1011, g1011), dot(g1111, g1111)));
    g0011 *= norm11.x;
    g0111 *= norm11.y;
    g1011 *= norm11.z;
    g1111 *= norm11.w;
    float n0000 = dot(g0000, Pf0);
    float n1000 = dot(g1000, vec4(Pf1.x, Pf0.yzw));
    float n0100 = dot(g0100, vec4(Pf0.x, Pf1.y, Pf0.zw));
    float n1100 = dot(g1100, vec4(Pf1.xy, Pf0.zw));
    float n0010 = dot(g0010, vec4(Pf0.xy, Pf1.z, Pf0.w));
    float n1010 = dot(g1010, vec4(Pf1.x, Pf0.y, Pf1.z, Pf0.w));
    float n0110 = dot(g0110, vec4(Pf0.x, Pf1.yz, Pf0.w));
    float n1110 = dot(g1110, vec4(Pf1.xyz, Pf0.w));
    float n0001 = dot(g0001, vec4(Pf0.xyz, Pf1.w));
    float n1001 = dot(g1001, vec4(Pf1.x, Pf0.yz, Pf1.w));
    float n0101 = dot(g0101, vec4(Pf0.x, Pf1.y, Pf0.z, Pf1.w));
    float n1101 = dot(g1101, vec4(Pf1.xy, Pf0.z, Pf1.w));
    float n0011 = dot(g0011, vec4(Pf0.xy, Pf1.zw));
    float n1011 = dot(g1011, vec4(Pf1.x, Pf0.y, Pf1.zw));
    float n0111 = dot(g0111, vec4(Pf0.x, Pf1.yzw));
    float n1111 = dot(g1111, Pf1);
    vec4 fade_xyzw = fade(Pf0);
    vec4 n_0w = mix(vec4(n0000, n1000, n0100, n1100), vec4(n0001, n1001, n0101, n1101), fade_xyzw.w);
    vec4 n_1w = mix(vec4(n0010, n1010, n0110, n1110), vec4(n0011, n1011, n0111, n1111), fade_xyzw.w);
    vec4 n_zw = mix(n_0w, n_1w, fade_xyzw.z);
    vec2 n_yzw = mix(n_zw.xy, n_zw.zw, fade_xyzw.y);
    float n_xyzw = mix(n_yzw.x, n_yzw.y, fade_xyzw.x);
    return 2.2 * n_xyzw;
    }
    ### [Simplex Noise](http://en.wikipedia.org/wiki/Simplex_noise)
    ```
    // Simplex 2D noise
    //
    vec3 permute(vec3 x) { return mod(((x*34.0)+1.0)*x, 289.0); }

    float snoise(vec2 v){
    const vec4 C = vec4(0.211324865405187, 0.366025403784439,
    -0.577350269189626, 0.024390243902439);
    vec2 i = floor(v + dot(v, C.yy) );
    vec2 x0 = v - i + dot(i, C.xx);
    vec2 i1;
    i1 = (x0.x > x0.y) ? vec2(1.0, 0.0) : vec2(0.0, 1.0);
    vec4 x12 = x0.xyxy + C.xxzz;
    x12.xy -= i1;
    i = mod(i, 289.0);
    vec3 p = permute( permute( i.y + vec3(0.0, i1.y, 1.0 ))
    + i.x + vec3(0.0, i1.x, 1.0 ));
    vec3 m = max(0.5 - vec3(dot(x0,x0), dot(x12.xy,x12.xy),
    dot(x12.zw,x12.zw)), 0.0);
    m = m*m ;
    m = m*m ;
    vec3 x = 2.0 * fract(p * C.www) - 1.0;
    vec3 h = abs(x) - 0.5;
    vec3 ox = floor(x + 0.5);
    vec3 a0 = x - ox;
    m *= 1.79284291400159 - 0.85373472095314 * ( a0*a0 + h*h );
    vec3 g;
    g.x = a0.x * x0.x + h.x * x0.y;
    g.yz = a0.yz * x12.xz + h.yz * x12.yw;
    return 130.0 * dot(m, g);
    }
    ```
    ```
    // Simplex 3D Noise
    // by Ian McEwan, Ashima Arts
    //
    vec4 permute(vec4 x){return mod(((x*34.0)+1.0)*x, 289.0);}
    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 * C
    vec3 x1 = x0 - i1 + 1.0 * C.xxx;
    vec3 x2 = x0 - i2 + 2.0 * C.xxx;
    vec3 x3 = x0 - 1. + 3.0 * C.xxx;

    // Permutations
    i = mod(i, 289.0 );
    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
    // ( N*N points uniformly over a square, mapped onto an octahedron.)
    float n_ = 1.0/7.0; // N=7
    vec3 ns = n_ * D.wyz - D.xzx;

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

    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 = 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) ) );
    }
    ```
    ```
    // Simplex 4D Noise
    // by Ian McEwan, Ashima Arts
    //
    vec4 permute(vec4 x){return mod(((x*34.0)+1.0)*x, 289.0);}
    float permute(float x){return floor(mod(((x*34.0)+1.0)*x, 289.0));}
    vec4 taylorInvSqrt(vec4 r){return 1.79284291400159 - 0.85373472095314 * r;}
    float taylorInvSqrt(float r){return 1.79284291400159 - 0.85373472095314 * r;}

    vec4 grad4(float j, vec4 ip){
    const vec4 ones = vec4(1.0, 1.0, 1.0, -1.0);
    vec4 p,s;

    p.xyz = floor( fract (vec3(j) * ip.xyz) * 7.0) * ip.z - 1.0;
    p.w = 1.5 - dot(abs(p.xyz), ones.xyz);
    s = vec4(lessThan(p, vec4(0.0)));
    p.xyz = p.xyz + (s.xyz*2.0 - 1.0) * s.www;

    return p;
    }

    float snoise(vec4 v){
    const vec2 C = vec2( 0.138196601125010504, // (5 - sqrt(5))/20 G4
    0.309016994374947451); // (sqrt(5) - 1)/4 F4
    // First corner
    vec4 i = floor(v + dot(v, C.yyyy) );
    vec4 x0 = v - i + dot(i, C.xxxx);

    // Other corners

    // Rank sorting originally contributed by Bill Licea-Kane, AMD (formerly ATI)
    vec4 i0;

    vec3 isX = step( x0.yzw, x0.xxx );
    vec3 isYZ = step( x0.zww, x0.yyz );
    // i0.x = dot( isX, vec3( 1.0 ) );
    i0.x = isX.x + isX.y + isX.z;
    i0.yzw = 1.0 - isX;

    // i0.y += dot( isYZ.xy, vec2( 1.0 ) );
    i0.y += isYZ.x + isYZ.y;
    i0.zw += 1.0 - isYZ.xy;

    i0.z += isYZ.z;
    i0.w += 1.0 - isYZ.z;

    // i0 now contains the unique values 0,1,2,3 in each channel
    vec4 i3 = clamp( i0, 0.0, 1.0 );
    vec4 i2 = clamp( i0-1.0, 0.0, 1.0 );
    vec4 i1 = clamp( i0-2.0, 0.0, 1.0 );

    // x0 = x0 - 0.0 + 0.0 * C
    vec4 x1 = x0 - i1 + 1.0 * C.xxxx;
    vec4 x2 = x0 - i2 + 2.0 * C.xxxx;
    vec4 x3 = x0 - i3 + 3.0 * C.xxxx;
    vec4 x4 = x0 - 1.0 + 4.0 * C.xxxx;

    // Permutations
    i = mod(i, 289.0);
    float j0 = permute( permute( permute( permute(i.w) + i.z) + i.y) + i.x);
    vec4 j1 = permute( permute( permute( permute (
    i.w + vec4(i1.w, i2.w, i3.w, 1.0 ))
    + i.z + vec4(i1.z, i2.z, i3.z, 1.0 ))
    + i.y + vec4(i1.y, i2.y, i3.y, 1.0 ))
    + i.x + vec4(i1.x, i2.x, i3.x, 1.0 ));
    // Gradients
    // ( 7*7*6 points uniformly over a cube, mapped onto a 4-octahedron.)
    // 7*7*6 = 294, which is close to the ring size 17*17 = 289.

    vec4 ip = vec4(1.0/294.0, 1.0/49.0, 1.0/7.0, 0.0) ;

    vec4 p0 = grad4(j0, ip);
    vec4 p1 = grad4(j1.x, ip);
    vec4 p2 = grad4(j1.y, ip);
    vec4 p3 = grad4(j1.z, ip);
    vec4 p4 = grad4(j1.w, ip);

    // 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;
    p4 *= taylorInvSqrt(dot(p4,p4));

    // Mix contributions from the five corners
    vec3 m0 = max(0.6 - vec3(dot(x0,x0), dot(x1,x1), dot(x2,x2)), 0.0);
    vec2 m1 = max(0.6 - vec2(dot(x3,x3), dot(x4,x4) ), 0.0);
    m0 = m0 * m0;
    m1 = m1 * m1;
    return 49.0 * ( dot(m0*m0, vec3( dot( p0, x0 ), dot( p1, x1 ), dot( p2, x2 )))
    + dot(m1*m1, vec2( dot( p3, x3 ), dot( p4, x4 ) ) ) ) ;

    }
    ```
    ```
    // <www.shadertoy.com/view/XsX3zB>
    // by Nikita Miropolskiy

    /* discontinuous pseudorandom uniformly distributed in [-0.5, +0.5]^3 */
    vec3 random3(vec3 c) {
    float j = 4096.0*sin(dot(c,vec3(17.0, 59.4, 15.0)));
    vec3 r;
    r.z = fract(512.0*j);
    j *= .125;
    r.x = fract(512.0*j);
    j *= .125;
    r.y = fract(512.0*j);
    return r-0.5;
    }

    const float F3 = 0.3333333;
    const float G3 = 0.1666667;
    float snoise(vec3 p) {

    vec3 s = floor(p + dot(p, vec3(F3)));
    vec3 x = p - s + dot(s, vec3(G3));
    vec3 e = step(vec3(0.0), x - x.yzx);
    vec3 i1 = e*(1.0 - e.zxy);
    vec3 i2 = 1.0 - e.zxy*(1.0 - e);
    vec3 x1 = x - i1 + G3;
    vec3 x2 = x - i2 + 2.0*G3;
    vec3 x3 = x - 1.0 + 3.0*G3;
    vec4 w, d;
    w.x = dot(x, x);
    w.y = dot(x1, x1);
    w.z = dot(x2, x2);
    w.w = dot(x3, x3);
    w = max(0.6 - w, 0.0);
    d.x = dot(random3(s), x);
    d.y = dot(random3(s + i1), x1);
    d.z = dot(random3(s + i2), x2);
    d.w = dot(random3(s + 1.0), x3);
    w *= w;
    w *= w;
    d *= w;
    return dot(d, vec4(52.0));
    }

    float snoiseFractal(vec3 m) {
    return 0.5333333* snoise(m)
    +0.2666667* snoise(2.0*m)
    +0.1333333* snoise(4.0*m)
    +0.0666667* snoise(8.0*m);
    }


    ```
    ## NOISE SubTypes
    ```
    // Blur noise
    //
    float smooth_noise(vec2 pos){
    return ( noise(pos + vec2(1,1)) + noise(pos + vec2(1,1)) + noise(pos + vec2(1,1)) + noise(pos + vec2(1,1)) ) / 16.0
    + ( noise(pos + vec2(1,0)) + noise(pos + vec2(-1,0)) + noise(pos + vec2(0,1)) + noise(pos + vec2(0,-1)) ) / 8.0
    + noise(pos) / 4.0;
    }

    // Linear interpolation
    //
    float interpolate_noise(vec2 pos){
    float a, b, c, d;

    a = smooth_noise(floor(pos));
    b = smooth_noise(vec2(floor(pos.x+1.0), floor(pos.y)));
    c = smooth_noise(vec2(floor(pos.x), floor(pos.y+1.0)));
    d = smooth_noise(vec2(floor(pos.x+1.0), floor(pos.y+1.0)));

    a = mix(a, b, fract(pos.x));
    b = mix(c, d, fract(pos.x));
    a = mix(a, b, fract(pos.y));

    return a;
    }
    ```
    ```
    // Noise Flow <https://www.shadertoy.com/view/lslXRS>
    // by nimitz (stormoid.com) (twitter: @stormoid)
    //
    mat2 makem2(in float theta){float c = cos(theta);float s = sin(theta);return mat2(c,-s,s,c);}

    vec2 gradn(vec2 p){
    float ep = .09;
    float gradx = noise(vec2(p.x+ep,p.y))-noise(vec2(p.x-ep,p.y));
    float grady = noise(vec2(p.x,p.y+ep))-noise(vec2(p.x,p.y-ep));
    return vec2(gradx,grady);
    }

    float flow(vec2 p){
    float z=2.;
    float rz = 0.;
    vec2 bp = p;
    for (float i= 1.;i < 7.;i++ ){
    //primary flow speed
    p += time*1.5;

    //secondary flow speed (speed of the perceived flow)
    bp += time*2.;

    //displacement field (try changing time multiplier)
    vec2 gr = gradn(i*p*.34+time*1.);

    //rotation of the displacement field
    gr*=makem2(time*10.-(0.05*p.x+0.03*p.y)*40.);

    //displace the system
    p += gr*.5;

    //add noise octave
    rz+= (sin(noise(p)*7.)*0.5+0.5)/z;

    //blend factor (blending displaced system with base system)
    //you could call this advection factor (.5 being low, .95 being high)
    p = mix(bp,p,.8);

    //intensity scaling
    z *= 1.4;
    //octave scaling
    p *= 2.;
    bp *= 1.9;
    }
    return rz;
    }
    ```
    ### NormalMap Noise
    ```
    vec3 normalNoise(vec2 _st, float _zoom, float _speed){
    vec2 v1 = _st;
    vec2 v2 = _st;
    vec2 v3 = _st;
    float expon = pow(10.0, _zoom*2.0);
    v1 /= 1.0*expon;
    v2 /= 0.62*expon;
    v3 /= 0.83*expon;
    float n = time*_speed;
    float nr = (simplexNoise(vec3(v1, n)) + simplexNoise(vec3(v2, n)) + simplexNoise(vec3(v3, n))) / 6.0 + 0.5;
    n = time * _speed + 1000.0;
    float ng = (simplexNoise(vec3(v1, n)) + simplexNoise(vec3(v2, n)) + simplexNoise(vec3(v3, n))) / 6.0 + 0.5;
    return vec3(nr,ng,0.5);
    }
    ```
    ## VoroNoise
    ```
    // <https://www.shadertoy.com/view/Xd23Dh>
    // by inigo quilez <http://iquilezles.org/www/articles/voronoise/voronoise.htm>
    //

    vec3 hash3( vec2 p ){
    vec3 q = vec3( dot(p,vec2(127.1,311.7)),
    dot(p,vec2(269.5,183.3)),
    dot(p,vec2(419.2,371.9)) );
    return fract(sin(q)*43758.5453);
    }

    float iqnoise( in vec2 x, float u, float v ){
    vec2 p = floor(x);
    vec2 f = fract(x);

    float k = 1.0+63.0*pow(1.0-v,4.0);

    float va = 0.0;
    float wt = 0.0;
    for( int j=-2; j<=2; j++ )
    for( int i=-2; i<=2; i++ )
    {
    vec2 g = vec2( float(i),float(j) );
    vec3 o = hash3( p + g )*vec3(u,u,1.0);
    vec2 r = g - f + o.xy;
    float d = dot(r,r);
    float ww = pow( 1.0-smoothstep(0.0,1.414,sqrt(d)), k );
    va += o.z*ww;
    wt += ww;
    }

    return va/wt;
    }

    ```
    ```
    // https://www.shadertoy.com/view/lsjGWD
    // by Pietro De Nicola
    //
    #define OCTAVES 1 // 7
    #define SWITCH_TIME 60.0 // seconds

    float t = time/SWITCH_TIME;

    float function = mod(t,4.0);
    bool multiply_by_F1 = mod(t,8.0) >= 4.0;
    bool inverse = mod(t,16.0) >= 8.0;
    float distance_type = mod(t/16.0,4.0);

    vec2 hash( vec2 p ){
    p = vec2( dot(p,vec2(127.1,311.7)),dot(p,vec2(269.5,183.3)));
    return fract(sin(p)*43758.5453);
    }

    float voronoi( in vec2 x ){
    vec2 n = floor( x );
    vec2 f = fract( x );

    float F1 = 8.0;
    float F2 = 8.0;

    for( int j=-1; j<=1; j++ )
    for( int i=-1; i<=1; i++ ){
    vec2 g = vec2(i,j);
    vec2 o = hash( n + g );

    o = 0.5 + 0.41*sin( time + 6.2831*o );
    vec2 r = g - f + o;

    float d = distance_type < 1.0 ? dot(r,r) : // euclidean^2
    distance_type < 2.0 ? sqrt(dot(r,r)) : // euclidean
    distance_type < 3.0 ? abs(r.x) + abs(r.y) : // manhattan
    distance_type < 4.0 ? max(abs(r.x), abs(r.y)) : // chebyshev
    0.0;

    if( d<F1 ) {
    F2 = F1;
    F1 = d;
    } else if( d<F2 ) {
    F2 = d;
    }
    }

    float c = function < 1.0 ? F1 :
    function < 2.0 ? F2 :
    function < 3.0 ? F2-F1 :
    function < 4.0 ? (F1+F2)/2.0 :
    0.0;
    if( multiply_by_F1 ) c *= F1;
    if( inverse ) c = 1.0 - c;

    return c;
    }

    float fbm( in vec2 p ){
    float s = 0.0;
    float m = 0.0;
    float a = 0.5;

    for( int i=0; i<OCTAVES; i++ ){
    s += a * voronoi(p);
    m += a;
    a *= 0.5;
    p *= 2.0;
    }
    return s/m;
    }

    // Use:
    // vec2 p = gl_FragCoord.xy/iResolution.xx;
    // float c = POWER*fbm( SCALE*p ) + BIAS;

    ```
    ## [Fractional Brownian motion](http://en.wikipedia.org/wiki/Fractional_Brownian_motion)
    ```
    #define NUM_OCTAVES 5

    float fbm(float x) {
    float v = 0.0;
    float a = 0.5;
    float shift = float(100);
    for (int i = 0; i < NUM_OCTAVES; ++i) {
    v += a * noise(x);
    x = x * 2.0 + shift;
    a *= 0.5;
    }
    return v;
    }


    float fbm(vec2 x) {
    float v = 0.0;
    float a = 0.5;
    vec2 shift = vec2(100);
    // 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 < NUM_OCTAVES; ++i) {
    v += a * noise(x);
    x = rot * x * 2.0 + shift;
    a *= 0.5;
    }
    return v;
    }


    float fbm(vec3 x) {
    float v = 0.0;
    float a = 0.5;
    vec3 shift = vec3(100);
    for (int i = 0; i < NUM_OCTAVES; ++i) {
    v += a * noise(x);
    x = x * 2.0 + shift;
    a *= 0.5;
    }
    return v;
    }
    ```
    ```
    // <https://www.shadertoy.com/view/MdX3Rr>
    // by inigo quilez
    //
    const mat2 m2 = mat2(1.6,-1.2,1.2,1.6);
    float fbm( in vec2 p ){
    float f = 0.0;
    f += 0.5000*noise( p ); p = m2*p*2.02;
    f += 0.2500*noise( p ); p = m2*p*2.03;
    f += 0.1250*noise( p ); p = m2*p*2.01;
    f += 0.0625*noise( p );

    return f/0.9375;
    }
    ```