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d3f630703f
the perlin.js is from https://github.com/leodeslf/perlin-noise and modified to work with node
307 lines
No EOL
6.2 KiB
JavaScript
307 lines
No EOL
6.2 KiB
JavaScript
/**
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* A Perlin Noise library for JavaScript.
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*
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* Based on implementations by Ken Perlin (Java, C) & Stefan Gustavson (C).
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*
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* MIT License.
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* Copyright (c) 2018 Leonardo de S.L.F.
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* http://leodeslf.com/
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*/
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// Permutation table.
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const p = [
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151, 160, 137, 91, 90, 15, 131, 13, 201, 95, 96, 53, 194, 233, 7, 225, 140,
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36, 103, 30, 69, 142, 8, 99, 37, 240, 21, 10, 23, 190, 6, 148, 247, 120, 234,
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75, 0, 26, 197, 62, 94, 252, 219, 203, 117, 35, 11, 32, 57, 177, 33, 88, 237,
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149, 56, 87, 174, 20, 125, 136, 171, 168, 68, 175, 74, 165, 71, 134, 139, 48,
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27, 166, 77, 146, 158, 231, 83, 111, 229, 122, 60, 211, 133, 230, 220, 105,
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92, 41, 55, 46, 245, 40, 244, 102, 143, 54, 65, 25, 63, 161, 1, 216, 80, 73,
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209, 76, 132, 187, 208, 89, 18, 169, 200, 196, 135, 130, 116, 188, 159, 86,
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164, 100, 109, 198, 173, 186, 3, 64, 52, 217, 226, 250, 124, 123, 5, 202, 38,
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147, 118, 126, 255, 82, 85, 212, 207, 206, 59, 227, 47, 16, 58, 17, 182, 189,
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28, 42, 223, 183, 170, 213, 119, 248, 152, 2, 44, 154, 163, 70, 221, 153,
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101, 155, 167, 43, 172, 9, 129, 22, 39, 253, 19, 98, 108, 110, 79, 113, 224,
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232, 178, 185, 112, 104, 218, 246, 97, 228, 251, 34, 242, 193, 238, 210, 144,
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12, 191, 179, 162, 241, 81, 51, 145, 235, 249, 14, 239, 107, 49, 192, 214,
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31, 181, 199, 106, 157, 184, 84, 204, 176, 115, 121, 50, 45, 127, 4, 150,
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254, 138, 236, 205, 93, 222, 114, 67, 29, 24, 72, 243, 141, 128, 195, 78, 66,
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215, 61, 156, 180
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];
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const P = [...p, ...p];
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// Utility functions.
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function fade(t) {
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return t * t * t * (t * (t * 6 - 15) + 10);
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}
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function lerp(t, a, b) {
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return a + t * (b - a);
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}
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// Helper functions to find gradients for each vertex.
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function gradient1D(hash, x) {
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return hash & 1 ? -x : x;
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}
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function gradient2D(hash, x, y) {
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const H = hash & 3;
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return (H < 2 ? x : -x) + (H === 0 || H === 2 ? y : -y);
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}
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function gradient3D(hash, x, y, z) {
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const
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H = hash & 15,
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U = H < 8 ? x : y,
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V = H < 4 ? y : H === 12 || H === 14 ? x : z;
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return ((H & 1) ? -U : U) + ((H & 2) ? -V : V);
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}
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function gradient4D(hash, x, y, z, t) {
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const
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H = hash & 31,
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U = H < 24 ? x : y,
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V = H < 16 ? y : z,
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W = H < 8 ? z : t;
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return ((H & 1) ? -U : U) + ((H & 2) ? -V : V) + ((H & 4) ? -W : W);
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}
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// Perlin Noise functions.
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/**
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* Returns a one-dimensional noise value between -1 and 1.
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* @param {number} x A numeric expression.
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* @returns {number} Perlin Noise value.
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*/
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function perlin1D(x) {
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const
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FX = Math.floor(x),
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X = FX & 255;
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x = x - FX;
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return lerp(
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fade(x),
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gradient1D(P[P[X]], x),
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gradient1D(P[P[X + 1]], x - 1)
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);
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}
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/**
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* Returns a two-dimensional noise value between -1 and 1.
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* @param {number} x A numeric expression.
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* @param {number} y A numeric expression.
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* @returns {number} Perlin Noise value.
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*/
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function perlin2D(x = 0, y = 0) {
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// Hack to allow this to work with integer block coords
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x += 0.2;
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y += 0.2;
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const FX = Math.floor(x),
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FY = Math.floor(y),
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X = FX & 255,
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Y = FY & 255,
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A = P[X] + Y,
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B = P[X + 1] + Y;
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x = x - FX;
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y = y - FY;
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const
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FDX = fade(x),
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x1 = x - 1,
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y1 = y - 1;
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return lerp(
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fade(y),
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lerp(
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FDX,
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gradient2D(P[A], x, y),
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gradient2D(P[B], x1, y)
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),
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lerp(
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FDX,
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gradient2D(P[A + 1], x, y1),
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gradient2D(P[B + 1], x1, y1)
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)
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);
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}
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/**
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* Returns a three-dimensional noise value between -1 and 1.
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* @param {number} x A numeric expression.
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* @param {number} y A numeric expression.
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* @param {number} z A numeric expression.
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* @returns {number} Perlin Noise value.
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*/
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function perlin3D(x, y, z) {
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const
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FX = Math.floor(x),
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FY = Math.floor(y),
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FZ = Math.floor(z),
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X = FX & 255,
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Y = FY & 255,
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Z = FZ & 255,
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A = P[X] + Y,
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B = P[X + 1] + Y,
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AA = P[A] + Z,
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BA = P[B] + Z,
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AB = P[A + 1] + Z,
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BB = P[B + 1] + Z;
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x = x - FX;
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y = y - FY;
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z = z - FZ;
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const
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FDX = fade(x),
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FDY = fade(y),
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x1 = x - 1,
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y1 = y - 1,
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z1 = z - 1;
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return lerp(
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fade(z),
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lerp(
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FDY,
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lerp(
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FDX,
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gradient3D(P[AA], x, y, z),
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gradient3D(P[BA], x1, y, z)
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),
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lerp(
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FDX,
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gradient3D(P[AB], x, y1, z),
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gradient3D(P[BB], x1, y1, z)
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)
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),
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lerp(
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FDY,
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lerp(
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FDX,
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gradient3D(P[AA + 1], x, y, z1),
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gradient3D(P[BA + 1], x1, y, z1)
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),
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lerp(
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FDX,
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gradient3D(P[AB + 1], x, y1, z1),
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gradient3D(P[BB + 1], x1, y1, z1)
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)
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)
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);
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}
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/**
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* Returns a four-dimensional noise value between -1 and 1.
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* @param {number} x A numeric expression.
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* @param {number} y A numeric expression.
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* @param {number} z A numeric expression.
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* @param {number} t A numeric expression.
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* @returns {number} Perlin Noise value.
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*/
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function perlin4D(x, y, z, t) {
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const
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FX = Math.floor(x),
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FY = Math.floor(y),
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FZ = Math.floor(z),
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FT = Math.floor(t),
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X = FX & 255,
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Y = FY & 255,
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Z = FZ & 255,
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T = FT & 255,
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A = P[X] + Y,
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B = P[X + 1] + Y,
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AA = P[A] + Z,
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BA = P[B] + Z,
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AB = P[A + 1] + Z,
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BB = P[B + 1] + Z,
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AAA = P[AA] + T,
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BAA = P[BA] + T,
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ABA = P[AB] + T,
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BBA = P[BB] + T,
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AAB = P[AA + 1] + T,
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BAB = P[BA + 1] + T,
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ABB = P[AB + 1] + T,
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BBB = P[BB + 1] + T;
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x = x - FX;
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y = y - FY;
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z = z - FZ;
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t = t - FT;
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const
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FDX = fade(x),
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FDY = fade(y),
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FDZ = fade(z),
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x1 = x - 1,
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y1 = y - 1,
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z1 = z - 1,
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t1 = t - 1;
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return lerp(
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fade(t),
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lerp(
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FDZ,
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lerp(
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FDY,
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lerp(
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FDX,
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gradient4D(P[AAA], x, y, z, t),
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gradient4D(P[BAA], x1, y, z, t)
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),
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lerp(
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FDX,
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gradient4D(P[ABA], x, y1, z, t),
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gradient4D(P[BBA], x1, y1, z, t)
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)
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),
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lerp(
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FDY,
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lerp(
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FDX,
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gradient4D(P[AAB], x, y, z1, t),
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gradient4D(P[BAB], x1, y, z1, t)
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),
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lerp(
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FDX,
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gradient4D(P[ABB], x, y1, z1, t),
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gradient4D(P[BBB], x1, y1, z1, t)
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)
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)
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),
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lerp(
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FDZ,
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lerp(
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FDY,
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lerp(
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FDX,
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gradient4D(P[AAA + 1], x, y, z, t1),
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gradient4D(P[BAA + 1], x1, y, z, t1)
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),
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lerp(
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FDX,
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gradient4D(P[ABA + 1], x, y1, z, t1),
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gradient4D(P[BBA + 1], x1, y1, z, t1)
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)
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),
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lerp(
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FDY,
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lerp(
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FDX,
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gradient4D(P[AAB + 1], x, y, z1, t1),
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gradient4D(P[BAB + 1], x1, y, z1, t1)
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),
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lerp(
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FDX,
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gradient4D(P[ABB + 1], x, y1, z1, t1),
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gradient4D(P[BBB + 1], x1, y1, z1, t1)
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)
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)
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)
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);
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}
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module.exports = { perlin1D, perlin2D, perlin3D, perlin4D }; |