1/* 2 * A speed-improved perlin and simplex noise algorithms for 2D. 3 * 4 * Based on example code by Stefan Gustavson ([email protected]). 5 * Optimisations by Peter Eastman ([email protected]). 6 * Better rank ordering method by Stefan Gustavson in 2012. 7 * Converted to Javascript by Joseph Gentle. 8 */ 9 10(function(global){ 11 var module = typeof exports === 'object' ? exports : (global.noise = {}); 12 13 function Grad(x, y, z) { 14 this.x = x; this.y = y; this.z = z; 15 } 16 17 Grad.prototype.dot2 = function(x, y) { 18 return this.x*x + this.y*y; 19 }; 20 21 Grad.prototype.dot3 = function(x, y, z) { 22 return this.x*x + this.y*y + this.z*z; 23 }; 24 25 var grad3 = [new Grad(1,1,0),new Grad(-1,1,0),new Grad(1,-1,0),new Grad(-1,-1,0), 26 new Grad(1,0,1),new Grad(-1,0,1),new Grad(1,0,-1),new Grad(-1,0,-1), 27 new Grad(0,1,1),new Grad(0,-1,1),new Grad(0,1,-1),new Grad(0,-1,-1)]; 28 29 var p = [151,160,137,91,90,15, 30 131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23, 31 190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33, 32 88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166, 33 77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244, 34 102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196, 35 135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123, 36 5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42, 37 223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9, 38 129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228, 39 251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107, 40 49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254, 41 138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180]; 42 // To remove the need for offsetIndex wrapping, double the permutation table length 43 var perm = new Array(512); 44 var gradP = new Array(512); 45 46 // This isn't a very good seeding function, but it works ok. It supports 2^16 47 // different seed values. Write something better if you need more seeds. 48 module.seed = function(seed) { 49 if(seed > 0 && seed < 1) { 50 // Scale the seed out 51 seed *= 65536; 52 } 53 54 seed = Math.floor(seed); 55 if(seed < 256) { 56 seed |= seed << 8; 57 } 58 59 for(var i = 0; i < 256; i++) { 60 var v; 61 if (i & 1) { 62 v = p[i] ^ (seed & 255); 63 } else { 64 v = p[i] ^ ((seed>>8) & 255); 65 } 66 67 perm[i] = perm[i + 256] = v; 68 gradP[i] = gradP[i + 256] = grad3[v % 12]; 69 } 70 }; 71 72 module.seed(0); 73 74 /* 75 for(var i=0; i<256; i++) { 76 perm[i] = perm[i + 256] = p[i]; 77 gradP[i] = gradP[i + 256] = grad3[perm[i] % 12]; 78 }*/ 79 80 // Skewing and unskewing factors for 2, 3, and 4 dimensions 81 var F2 = 0.5*(Math.sqrt(3)-1); 82 var G2 = (3-Math.sqrt(3))/6; 83 84 var F3 = 1/3; 85 var G3 = 1/6; 86 87 // 2D simplex noise 88 module.simplex2 = function(xin, yin) { 89 var n0, n1, n2; // Noise contributions from the three corners 90 // Skew the input space to determine which simplex cell we're in 91 var s = (xin+yin)*F2; // Hairy factor for 2D 92 var i = Math.floor(xin+s); 93 var j = Math.floor(yin+s); 94 var t = (i+j)*G2; 95 var x0 = xin-i+t; // The x,y distances from the cell origin, unskewed. 96 var y0 = yin-j+t; 97 // For the 2D case, the simplex shape is an equilateral triangle. 98 // Determine which simplex we are in. 99 var i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords 100 if(x0>y0) { // lower triangle, XY order: (0,0)->(1,0)->(1,1) 101 i1=1; j1=0; 102 } else { // upper triangle, YX order: (0,0)->(0,1)->(1,1) 103 i1=0; j1=1; 104 } 105 // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and 106 // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where 107 // c = (3-sqrt(3))/6 108 var x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords 109 var y1 = y0 - j1 + G2; 110 var x2 = x0 - 1 + 2 * G2; // Offsets for last corner in (x,y) unskewed coords
vendor: 4,289 bytes, lines 111-248
111 var y2 = y0 - 1 + 2 * G2; 112 // Work out the hashed gradient indices of the three simplex corners 113 i &= 255; 114 j &= 255; 115 var gi0 = gradP[i+perm[j]]; 116 var gi1 = gradP[i+i1+perm[j+j1]]; 117 var gi2 = gradP[i+1+perm[j+1]]; 118 // Calculate the contribution from the three corners 119 var t0 = 0.5 - x0*x0-y0*y0; 120 if(t0<0) { 121 n0 = 0; 122 } else { 123 t0 *= t0; 124 n0 = t0 * t0 * gi0.dot2(x0, y0); // (x,y) of grad3 used for 2D gradient 125 } 126 var t1 = 0.5 - x1*x1-y1*y1; 127 if(t1<0) { 128 n1 = 0; 129 } else { 130 t1 *= t1; 131 n1 = t1 * t1 * gi1.dot2(x1, y1); 132 } 133 var t2 = 0.5 - x2*x2-y2*y2; 134 if(t2<0) { 135 n2 = 0; 136 } else { 137 t2 *= t2; 138 n2 = t2 * t2 * gi2.dot2(x2, y2); 139 } 140 // Add contributions from each corner to get the final noise value. 141 // The result is scaled to return values in the interval [-1,1]. 142 return 70 * (n0 + n1 + n2); 143 }; 144 145 // 3D simplex noise 146 module.simplex3 = function(xin, yin, zin) { 147 var n0, n1, n2, n3; // Noise contributions from the four corners 148 149 // Skew the input space to determine which simplex cell we're in 150 var s = (xin+yin+zin)*F3; // Hairy factor for 2D 151 var i = Math.floor(xin+s); 152 var j = Math.floor(yin+s); 153 var k = Math.floor(zin+s); 154 155 var t = (i+j+k)*G3; 156 var x0 = xin-i+t; // The x,y distances from the cell origin, unskewed. 157 var y0 = yin-j+t; 158 var z0 = zin-k+t; 159 160 // For the 3D case, the simplex shape is a slightly irregular tetrahedron. 161 // Determine which simplex we are in. 162 var i1, j1, k1; // Offsets for second corner of simplex in (i,j,k) coords 163 var i2, j2, k2; // Offsets for third corner of simplex in (i,j,k) coords 164 if(x0 >= y0) { 165 if(y0 >= z0) { i1=1; j1=0; k1=0; i2=1; j2=1; k2=0; } 166 else if(x0 >= z0) { i1=1; j1=0; k1=0; i2=1; j2=0; k2=1; } 167 else { i1=0; j1=0; k1=1; i2=1; j2=0; k2=1; } 168 } else { 169 if(y0 < z0) { i1=0; j1=0; k1=1; i2=0; j2=1; k2=1; } 170 else if(x0 < z0) { i1=0; j1=1; k1=0; i2=0; j2=1; k2=1; } 171 else { i1=0; j1=1; k1=0; i2=1; j2=1; k2=0; } 172 } 173 // A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z), 174 // a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and 175 // a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where 176 // c = 1/6. 177 var x1 = x0 - i1 + G3; // Offsets for second corner 178 var y1 = y0 - j1 + G3; 179 var z1 = z0 - k1 + G3; 180 181 var x2 = x0 - i2 + 2 * G3; // Offsets for third corner 182 var y2 = y0 - j2 + 2 * G3; 183 var z2 = z0 - k2 + 2 * G3; 184 185 var x3 = x0 - 1 + 3 * G3; // Offsets for fourth corner 186 var y3 = y0 - 1 + 3 * G3; 187 var z3 = z0 - 1 + 3 * G3; 188 189 // Work out the hashed gradient indices of the four simplex corners 190 i &= 255; 191 j &= 255; 192 k &= 255; 193 var gi0 = gradP[i+ perm[j+ perm[k ]]]; 194 var gi1 = gradP[i+i1+perm[j+j1+perm[k+k1]]]; 195 var gi2 = gradP[i+i2+perm[j+j2+perm[k+k2]]]; 196 var gi3 = gradP[i+ 1+perm[j+ 1+perm[k+ 1]]]; 197 198 // Calculate the contribution from the four corners 199 var t0 = 0.6 - x0*x0 - y0*y0 - z0*z0; 200 if(t0<0) { 201 n0 = 0; 202 } else { 203 t0 *= t0; 204 n0 = t0 * t0 * gi0.dot3(x0, y0, z0); // (x,y) of grad3 used for 2D gradient 205 } 206 var t1 = 0.6 - x1*x1 - y1*y1 - z1*z1; 207 if(t1<0) { 208 n1 = 0; 209 } else { 210 t1 *= t1; 211 n1 = t1 * t1 * gi1.dot3(x1, y1, z1); 212 } 213 var t2 = 0.6 - x2*x2 - y2*y2 - z2*z2; 214 if(t2<0) { 215 n2 = 0; 216 } else { 217 t2 *= t2; 218 n2 = t2 * t2 * gi2.dot3(x2, y2, z2); 219 } 220 var t3 = 0.6 - x3*x3 - y3*y3 - z3*z3; 221 if(t3<0) { 222 n3 = 0; 223 } else { 224 t3 *= t3; 225 n3 = t3 * t3 * gi3.dot3(x3, y3, z3); 226 } 227 // Add contributions from each corner to get the final noise value. 228 // The result is scaled to return values in the interval [-1,1]. 229 return 32 * (n0 + n1 + n2 + n3); 230 231 }; 232 233 // ##### Perlin noise stuff 234 235 function fade(t) { 236 return t*t*t*(t*(t*6-15)+10); 237 } 238 239 function lerp(a, b, t) { 240 return (1-t)*a + t*b; 241 } 242 243 // 2D Perlin Noise 244 module.perlin2 = function(x, y) { 245 // Find unit grid cell containing point 246 var X = Math.floor(x), Y = Math.floor(y); 247 // Get relative xy coordinates of point within that cell 248 x = x - X; y = y - Y;
vendor: 1,903 bytes, lines 249-303
249 // Wrap the integer cells at 255 (smaller integer period can be introduced here) 250 X = X & 255; Y = Y & 255; 251 252 // Calculate noise contributions from each of the four corners 253 var n00 = gradP[X+perm[Y]].dot2(x, y); 254 var n01 = gradP[X+perm[Y+1]].dot2(x, y-1); 255 var n10 = gradP[X+1+perm[Y]].dot2(x-1, y); 256 var n11 = gradP[X+1+perm[Y+1]].dot2(x-1, y-1); 257 258 // Compute the fade curve value for x 259 var u = fade(x); 260 261 // Interpolate the four results 262 return lerp( 263 lerp(n00, n10, u), 264 lerp(n01, n11, u), 265 fade(y)); 266 }; 267 268 // 3D Perlin Noise 269 module.perlin3 = function(x, y, z) { 270 // Find unit grid cell containing point 271 var X = Math.floor(x), Y = Math.floor(y), Z = Math.floor(z); 272 // Get relative xyz coordinates of point within that cell 273 x = x - X; y = y - Y; z = z - Z; 274 // Wrap the integer cells at 255 (smaller integer period can be introduced here) 275 X = X & 255; Y = Y & 255; Z = Z & 255; 276 277 // Calculate noise contributions from each of the eight corners 278 var n000 = gradP[X+ perm[Y+ perm[Z ]]].dot3(x, y, z); 279 var n001 = gradP[X+ perm[Y+ perm[Z+1]]].dot3(x, y, z-1); 280 var n010 = gradP[X+ perm[Y+1+perm[Z ]]].dot3(x, y-1, z); 281 var n011 = gradP[X+ perm[Y+1+perm[Z+1]]].dot3(x, y-1, z-1); 282 var n100 = gradP[X+1+perm[Y+ perm[Z ]]].dot3(x-1, y, z); 283 var n101 = gradP[X+1+perm[Y+ perm[Z+1]]].dot3(x-1, y, z-1); 284 var n110 = gradP[X+1+perm[Y+1+perm[Z ]]].dot3(x-1, y-1, z); 285 var n111 = gradP[X+1+perm[Y+1+perm[Z+1]]].dot3(x-1, y-1, z-1); 286 287 // Compute the fade curve value for x, y, z 288 var u = fade(x); 289 var v = fade(y); 290 var w = fade(z); 291 292 // Interpolate 293 return lerp( 294 lerp( 295 lerp(n000, n100, u), 296 lerp(n001, n101, u), w), 297 lerp( 298 lerp(n010, n110, u), 299 lerp(n011, n111, u), w), 300 v); 301 }; 302 303})(this);
Line numbers count LF bytes from the start of the resource, as the search results do. Vendor segments are library code the classifier recognised; they are stored but not indexed. Bytes are shown as Latin1 characters, one per byte.