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mobile-query-three-vendor-three-r53.js-ImprovedNoise.js / js



  // http://mrl.nyu.edu/~perlin/noise/
  
  var ImprovedNoise = function () {
  
          var p = [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];
  
          for (var i=0; i < 256 ; i++) {
  
                  p[256+i] = p[i];
  
          }
  
          function fade(t) {
  
                  return t * t * t * (t * (t * 6 - 15) + 10);
  
          }
  
          function lerp(t, a, b) {
  
                  return a + t * (b - a);
  
          }
  
          function grad(hash, x, y, z) {
  
                  var h = hash & 15;
                  var u = h < 8 ? x : y, v = h < 4 ? y : h == 12 || h == 14 ? x : z;
                  return ((h&1) == 0 ? u : -u) + ((h&2) == 0 ? v : -v);
  
          }
  
          return {
  
                  noise: function (x, y, z) {
  
                          var floorX = ~~x, floorY = ~~y, floorZ = ~~z;
  
                          var X = floorX & 255, Y = floorY & 255, Z = floorZ & 255;
  
                          x -= floorX;
                          y -= floorY;
                          z -= floorZ;
  
                          var xMinus1 = x -1, yMinus1 = y - 1, zMinus1 = z - 1;
  
                          var u = fade(x), v = fade(y), w = fade(z);
  
                          var A = p[X]+Y, AA = p[A]+Z, AB = p[A+1]+Z, B = p[X+1]+Y, BA = p[B]+Z, BB = p[B+1]+Z;
  
                          return lerp(w, lerp(v, lerp(u, grad(p[AA], x, y, z), 
                                                          grad(p[BA], xMinus1, y, z)),
                                                  lerp(u, grad(p[AB], x, yMinus1, z),
                                                          grad(p[BB], xMinus1, yMinus1, z))),
                                          lerp(v, lerp(u, grad(p[AA+1], x, y, zMinus1),
                                                          grad(p[BA+1], xMinus1, y, z-1)),
                                                  lerp(u, grad(p[AB+1], x, yMinus1, zMinus1),
                                                          grad(p[BB+1], xMinus1, yMinus1, zMinus1))));
  
                  }
          }
  }
  


(C) Æliens 04/09/2009

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