Visualization toolmaker. Founder @observablehq. Creator @d3. Former @nytgraphics. Pronounced BOSS-tock.
Public
Edited
Apr 18, 2023
3 forks
Importers
23 stars
function perlin3(x, y, z) {
const xi = Math.floor(x), yi = Math.floor(y), zi = Math.floor(z);
const X = xi & 255, Y = yi & 255, Z = zi & 255;
const u = fade(x -= xi), v = fade(y -= yi), w = fade(z -= zi);
const A = p[X] + Y, AA = p[A] + Z, AB = p[A + 1] + Z;
const B = p[X + 1] + Y, BA = p[B] + Z, BB = p[B + 1] + Z;
return lerp(
w,
lerp(
v,
lerp(u, grad3(p[AA], x, y, z), grad3(p[BA], x - 1, y, z)),
lerp(u, grad3(p[AB], x, y - 1, z), grad3(p[BB], x - 1, y - 1, z))
),
lerp(
v,
lerp(u, grad3(p[AA + 1], x, y, z - 1), grad3(p[BA + 1], x - 1, y, z - 1)),
lerp(u, grad3(p[AB + 1], x, y - 1, z - 1), grad3(p[BB + 1], x - 1, y - 1, z - 1))
)
);
}
function perlin2(x, y) {
const xi = Math.floor(x), yi = Math.floor(y);
const X = xi & 255, Y = yi & 255;
const u = fade(x -= xi), v = fade(y -= yi);
const A = p[X] + Y, B = p[X + 1] + Y;
return lerp(
v,
lerp(u, grad2(p[A], x, y), grad2(p[B], x - 1, y)),
lerp(u, grad2(p[A + 1], x, y - 1), grad2(p[B + 1], x - 1, y - 1))
);
}
function octave(noise, octaves) {
return function(x, y, z) {
let total = 0;
let frequency = 1;
let amplitude = 1;
let value = 0;
for (let i = 0; i < octaves; ++i) {
value += noise(x * frequency, y * frequency, z * frequency) * amplitude;
total += amplitude;
amplitude *= 0.5;
frequency *= 2;
}
return value / total;
};
}
function grad3(i, x, y, z) {
const h = i & 15;
const u = h < 8 ? x : y;
const v = h < 4 ? y : h === 12 || h === 14 ? x : z;
return (h & 1 ? -u : u) + (h & 2 ? -v : v);
}
function grad2(i, x, y) {
const v = i & 1 ? y : x;
return i & 2 ? -v : v;
}
function fade(t) {
return t * t * t * (t * (t * 6 - 15) + 10);
}
function lerp(t, a, b) {
return a + t * (b - a);
}
// const P = new Uint8Array(256);
// for (let i = 0; i < 256; ++i) P[i] = i;
// d3.shuffle(P);
P = Uint8Array.of(151,160,137,91,90,15,131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,190,6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,88,237,149,56,87,174,20,125,136,171,168,68,175,74,165,71,134,139,48,27,166,77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,102,143,54,65,25,63,161,1,216,80,73,209,76,132,187,208,89,18,169,200,196,135,130,116,188,159,86,164,100,109,198,173,186,3,64,52,217,226,250,124,123,5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,223,183,170,213,119,248,152,2,44,154,163,70,221,153,101,155,167,43,172,9,129,22,39,253,19,98,108,110,79,113,224,232,178,185,112,104,218,246,97,228,251,34,242,193,238,210,144,12,191,179,162,241,81,51,145,235,249,14,239,107,49,192,214,31,181,199,106,157,184,84,204,176,115,121,50,45,127,4,150,254,138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180)
p = {
const p = new Uint8Array(512);
for (let i = 0; i < 256; ++i) p[i] = p[i + 256] = P[i];
return p;
}
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
