/* * A fast javascript implementation of simplex noise by Jonas Wagner * * Based on a speed-improved simplex noise algorithm for 2D, 3D and 4D in Java. * Which is based on example code by Stefan Gustavson (stegu@itn.liu.se). * With Optimisations by Peter Eastman (peastman@drizzle.stanford.edu). * Better rank ordering method by Stefan Gustavson in 2012. * * * Copyright (C) 2016 Jonas Wagner * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * */ (function() { 'use strict'; var F2 = 0.5 * (Math.sqrt(3.0) - 1.0); var G2 = (3.0 - Math.sqrt(3.0)) / 6.0; var F3 = 1.0 / 3.0; var G3 = 1.0 / 6.0; var F4 = (Math.sqrt(5.0) - 1.0) / 4.0; var G4 = (5.0 - Math.sqrt(5.0)) / 20.0; function SimplexNoise(random) { if (!random) random = Math.random; this.p = buildPermutationTable(random); this.perm = new Uint8Array(512); this.permMod12 = new Uint8Array(512); for (var i = 0; i < 512; i++) { this.perm[i] = this.p[i & 255]; this.permMod12[i] = this.perm[i] % 12; } } SimplexNoise.prototype = { grad3: new Float32Array([1, 1, 0, -1, 1, 0, 1, -1, 0, -1, -1, 0, 1, 0, 1, -1, 0, 1, 1, 0, -1, -1, 0, -1, 0, 1, 1, 0, -1, 1, 0, 1, -1, 0, -1, -1]), grad4: new Float32Array([0, 1, 1, 1, 0, 1, 1, -1, 0, 1, -1, 1, 0, 1, -1, -1, 0, -1, 1, 1, 0, -1, 1, -1, 0, -1, -1, 1, 0, -1, -1, -1, 1, 0, 1, 1, 1, 0, 1, -1, 1, 0, -1, 1, 1, 0, -1, -1, -1, 0, 1, 1, -1, 0, 1, -1, -1, 0, -1, 1, -1, 0, -1, -1, 1, 1, 0, 1, 1, 1, 0, -1, 1, -1, 0, 1, 1, -1, 0, -1, -1, 1, 0, 1, -1, 1, 0, -1, -1, -1, 0, 1, -1, -1, 0, -1, 1, 1, 1, 0, 1, 1, -1, 0, 1, -1, 1, 0, 1, -1, -1, 0, -1, 1, 1, 0, -1, 1, -1, 0, -1, -1, 1, 0, -1, -1, -1, 0]), noise2D: function(xin, yin) { var permMod12 = this.permMod12; var perm = this.perm; var grad3 = this.grad3; var n0 = 0; // Noise contributions from the three corners var n1 = 0; var n2 = 0; // Skew the input space to determine which simplex cell we're in var s = (xin + yin) * F2; // Hairy factor for 2D var i = Math.floor(xin + s); var j = Math.floor(yin + s); var t = (i + j) * G2; var X0 = i - t; // Unskew the cell origin back to (x,y) space var Y0 = j - t; var x0 = xin - X0; // The x,y distances from the cell origin var y0 = yin - Y0; // For the 2D case, the simplex shape is an equilateral triangle. // Determine which simplex we are in. var i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords if (x0 > y0) { i1 = 1; j1 = 0; } // lower triangle, XY order: (0,0)->(1,0)->(1,1) else { i1 = 0; j1 = 1; } // upper triangle, YX order: (0,0)->(0,1)->(1,1) // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where // c = (3-sqrt(3))/6 var x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords var y1 = y0 - j1 + G2; var x2 = x0 - 1.0 + 2.0 * G2; // Offsets for last corner in (x,y) unskewed coords var y2 = y0 - 1.0 + 2.0 * G2; // Work out the hashed gradient indices of the three simplex corners var ii = i & 255; var jj = j & 255; // Calculate the contribution from the three corners var t0 = 0.5 - x0 * x0 - y0 * y0; if (t0 >= 0) { var gi0 = permMod12[ii + perm[jj]] * 3; t0 *= t0; n0 = t0 * t0 * (grad3[gi0] * x0 + grad3[gi0 + 1] * y0); // (x,y) of grad3 used for 2D gradient } var t1 = 0.5 - x1 * x1 - y1 * y1; if (t1 >= 0) { var gi1 = permMod12[ii + i1 + perm[jj + j1]] * 3; t1 *= t1; n1 = t1 * t1 * (grad3[gi1] * x1 + grad3[gi1 + 1] * y1); } var t2 = 0.5 - x2 * x2 - y2 * y2; if (t2 >= 0) { var gi2 = permMod12[ii + 1 + perm[jj + 1]] * 3; t2 *= t2; n2 = t2 * t2 * (grad3[gi2] * x2 + grad3[gi2 + 1] * y2); } // Add contributions from each corner to get the final noise value. // The result is scaled to return values in the interval [-1,1]. return 70.0 * (n0 + n1 + n2); }, // 3D simplex noise noise3D: function(xin, yin, zin) { var permMod12 = this.permMod12; var perm = this.perm; var grad3 = this.grad3; var n0, n1, n2, n3; // Noise contributions from the four corners // Skew the input space to determine which simplex cell we're in var s = (xin + yin + zin) * F3; // Very nice and simple skew factor for 3D var i = Math.floor(xin + s); var j = Math.floor(yin + s); var k = Math.floor(zin + s); var t = (i + j + k) * G3; var X0 = i - t; // Unskew the cell origin back to (x,y,z) space var Y0 = j - t; var Z0 = k - t; var x0 = xin - X0; // The x,y,z distances from the cell origin var y0 = yin - Y0; var z0 = zin - Z0; // For the 3D case, the simplex shape is a slightly irregular tetrahedron. // Determine which simplex we are in. var i1, j1, k1; // Offsets for second corner of simplex in (i,j,k) coords var i2, j2, k2; // Offsets for third corner of simplex in (i,j,k) coords if (x0 >= y0) { if (y0 >= z0) { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 1; k2 = 0; } // X Y Z order else if (x0 >= z0) { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 0; k2 = 1; } // X Z Y order else { i1 = 0; j1 = 0; k1 = 1; i2 = 1; j2 = 0; k2 = 1; } // Z X Y order } else { // x0 y0) rankx++; else ranky++; if (x0 > z0) rankx++; else rankz++; if (x0 > w0) rankx++; else rankw++; if (y0 > z0) ranky++; else rankz++; if (y0 > w0) ranky++; else rankw++; if (z0 > w0) rankz++; else rankw++; var i1, j1, k1, l1; // The integer offsets for the second simplex corner var i2, j2, k2, l2; // The integer offsets for the third simplex corner var i3, j3, k3, l3; // The integer offsets for the fourth simplex corner // simplex[c] is a 4-vector with the numbers 0, 1, 2 and 3 in some order. // Many values of c will never occur, since e.g. x>y>z>w makes x= 3 ? 1 : 0; j1 = ranky >= 3 ? 1 : 0; k1 = rankz >= 3 ? 1 : 0; l1 = rankw >= 3 ? 1 : 0; // Rank 2 denotes the second largest coordinate. i2 = rankx >= 2 ? 1 : 0; j2 = ranky >= 2 ? 1 : 0; k2 = rankz >= 2 ? 1 : 0; l2 = rankw >= 2 ? 1 : 0; // Rank 1 denotes the second smallest coordinate. i3 = rankx >= 1 ? 1 : 0; j3 = ranky >= 1 ? 1 : 0; k3 = rankz >= 1 ? 1 : 0; l3 = rankw >= 1 ? 1 : 0; // The fifth corner has all coordinate offsets = 1, so no need to compute that. var x1 = x0 - i1 + G4; // Offsets for second corner in (x,y,z,w) coords var y1 = y0 - j1 + G4; var z1 = z0 - k1 + G4; var w1 = w0 - l1 + G4; var x2 = x0 - i2 + 2.0 * G4; // Offsets for third corner in (x,y,z,w) coords var y2 = y0 - j2 + 2.0 * G4; var z2 = z0 - k2 + 2.0 * G4; var w2 = w0 - l2 + 2.0 * G4; var x3 = x0 - i3 + 3.0 * G4; // Offsets for fourth corner in (x,y,z,w) coords var y3 = y0 - j3 + 3.0 * G4; var z3 = z0 - k3 + 3.0 * G4; var w3 = w0 - l3 + 3.0 * G4; var x4 = x0 - 1.0 + 4.0 * G4; // Offsets for last corner in (x,y,z,w) coords var y4 = y0 - 1.0 + 4.0 * G4; var z4 = z0 - 1.0 + 4.0 * G4; var w4 = w0 - 1.0 + 4.0 * G4; // Work out the hashed gradient indices of the five simplex corners var ii = i & 255; var jj = j & 255; var kk = k & 255; var ll = l & 255; // Calculate the contribution from the five corners var t0 = 0.6 - x0 * x0 - y0 * y0 - z0 * z0 - w0 * w0; if (t0 < 0) n0 = 0.0; else { var gi0 = (perm[ii + perm[jj + perm[kk + perm[ll]]]] % 32) * 4; t0 *= t0; n0 = t0 * t0 * (grad4[gi0] * x0 + grad4[gi0 + 1] * y0 + grad4[gi0 + 2] * z0 + grad4[gi0 + 3] * w0); } var t1 = 0.6 - x1 * x1 - y1 * y1 - z1 * z1 - w1 * w1; if (t1 < 0) n1 = 0.0; else { var gi1 = (perm[ii + i1 + perm[jj + j1 + perm[kk + k1 + perm[ll + l1]]]] % 32) * 4; t1 *= t1; n1 = t1 * t1 * (grad4[gi1] * x1 + grad4[gi1 + 1] * y1 + grad4[gi1 + 2] * z1 + grad4[gi1 + 3] * w1); } var t2 = 0.6 - x2 * x2 - y2 * y2 - z2 * z2 - w2 * w2; if (t2 < 0) n2 = 0.0; else { var gi2 = (perm[ii + i2 + perm[jj + j2 + perm[kk + k2 + perm[ll + l2]]]] % 32) * 4; t2 *= t2; n2 = t2 * t2 * (grad4[gi2] * x2 + grad4[gi2 + 1] * y2 + grad4[gi2 + 2] * z2 + grad4[gi2 + 3] * w2); } var t3 = 0.6 - x3 * x3 - y3 * y3 - z3 * z3 - w3 * w3; if (t3 < 0) n3 = 0.0; else { var gi3 = (perm[ii + i3 + perm[jj + j3 + perm[kk + k3 + perm[ll + l3]]]] % 32) * 4; t3 *= t3; n3 = t3 * t3 * (grad4[gi3] * x3 + grad4[gi3 + 1] * y3 + grad4[gi3 + 2] * z3 + grad4[gi3 + 3] * w3); } var t4 = 0.6 - x4 * x4 - y4 * y4 - z4 * z4 - w4 * w4; if (t4 < 0) n4 = 0.0; else { var gi4 = (perm[ii + 1 + perm[jj + 1 + perm[kk + 1 + perm[ll + 1]]]] % 32) * 4; t4 *= t4; n4 = t4 * t4 * (grad4[gi4] * x4 + grad4[gi4 + 1] * y4 + grad4[gi4 + 2] * z4 + grad4[gi4 + 3] * w4); } // Sum up and scale the result to cover the range [-1,1] return 27.0 * (n0 + n1 + n2 + n3 + n4); } }; function buildPermutationTable(random) { var i; var p = new Uint8Array(256); for (i = 0; i < 256; i++) { p[i] = i; } for (i = 0; i < 255; i++) { var r = i + ~~(random() * (256 - i)); var aux = p[i]; p[i] = p[r]; p[r] = aux; } return p; } SimplexNoise._buildPermutationTable = buildPermutationTable; // amd if (typeof define !== 'undefined' && define.amd) define(function() {return SimplexNoise;}); // common js if (typeof exports !== 'undefined') exports.SimplexNoise = SimplexNoise; // browser else if (typeof window !== 'undefined') window.SimplexNoise = SimplexNoise; // nodejs if (typeof module !== 'undefined') { module.exports = SimplexNoise; } })();