util/pnoise.py

   1 #
   2 # A python perlin noise implementation, from
   3 # http://www.fundza.com/c4serious/noise/perlin/perlin.html
   4 #
   5 # This is used for testing how to create maps with a python script.
   6 #
   7
   8 import math
   9 p = (
  10 151,160,137,91,90,15,131,13,201,95,96,53,194,233,7,225,140,36,103,
  11 30,69,142,8,99,37,240,21,10,23,190,6,148,247,120,234,75,0,26,197,
  12 62,94,252,219,203,117,35,11,32,57,177,33,88,237,149,56,87,174,20,
  13 125,136,171,168,68,175,74,165,71,134,139,48,27,166,77,146,158,231,
  14 83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,102,
  15 143,54,65,25,63,161,1,216,80,73,209,76,132,187,208,89,18,169,200,
  16 196,135,130,116,188,159,86,164,100,109,198,173,186,3,64,52,217,226,
  17 250,124,123,5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,
  18 58,17,182,189,28,42,223,183,170,213,119,248,152,2,44,154,163,70,
  19 221,153,101,155,167,43,172,9,129,22,39,253,19,98,108,110,79,113,
  20 224,232,178,185,112,104,218,246,97,228,251,34,242,193,238,210,144,
  21 12,191,179,162,241,81,51,145,235,249,14,239,107,49,192,214,31,181,
  22 199,106,157,184,84,204,176,115,121,50,45,127,4,150,254,138,236,
  23 205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180,
  24 151,160,137,91,90,15,131,13,201,95,96,53,194,233,7,225,140,36,103,
  25 30,69,142,8,99,37,240,21,10,23,190,6,148,247,120,234,75,0,26,197,
  26 62,94,252,219,203,117,35,11,32,57,177,33,88,237,149,56,87,174,20,
  27 125,136,171,168,68,175,74,165,71,134,139,48,27,166,77,146,158,231,
  28 83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,102,
  29 143,54,65,25,63,161,1,216,80,73,209,76,132,187,208,89,18,169,200,
  30 196,135,130,116,188,159,86,164,100,109,198,173,186,3,64,52,217,226,
  31 250,124,123,5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,
  32 58,17,182,189,28,42,223,183,170,213,119,248,152,2,44,154,163,70,
  33 221,153,101,155,167,43,172,9,129,22,39,253,19,98,108,110,79,113,
  34 224,232,178,185,112,104,218,246,97,228,251,34,242,193,238,210,144,
  35 12,191,179,162,241,81,51,145,235,249,14,239,107,49,192,214,31,181,
  36 199,106,157,184,84,204,176,115,121,50,45,127,4,150,254,138,236,
  37 205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180)
  38
  39 def lerp(t, a, b):
  40     return a + t * (b - a)
  41
  42 def fade(t):
  43     return t * t * t * (t * (t * 6 - 15) + 10)
  44
  45 def grad(hash, x, y, z):
  46     h = hash & 15
  47     if h < 8:
  48         u = x
  49     else:
  50         u = y
  51     if h < 4:
  52         v = y
  53     elif h == 12 or h == 14:
  54         v = x
  55     else:
  56         v = z
  57     if h & 1 != 0:
  58         u = -u
  59     if h & 2 != 0:
  60         v = -v
  61     return u + v
  62
  63 def pnoise(x, y, z):
  64     global p
  65     X = int(math.floor(x)) & 255
  66     Y = int(math.floor(y)) & 255
  67     Z = int(math.floor(z)) & 255
  68     x -= math.floor(x)
  69     y -= math.floor(y)
  70     z -= math.floor(z)
  71
  72     u = fade(x)
  73     v = fade(y)
  74     w = fade(z)
  75
  76     A =  p[X] + Y
  77     AA = p[A] + Z
  78     AB = p[A + 1] + Z
  79     B =  p[X + 1] + Y
  80     BA = p[B] + Z
  81     BB = p[B + 1] + Z
  82
  83     pAA = p[AA]
  84     pAB = p[AB]
  85     pBA = p[BA]
  86     pBB = p[BB]
  87     pAA1 = p[AA + 1]
  88     pBA1 = p[BA + 1]
  89     pAB1 = p[AB + 1]
  90     pBB1 = p[BB + 1]
  91
  92     gradAA =  grad(pAA, x,   y,   z)
  93     gradBA =  grad(pBA, x-1, y,   z)
  94     gradAB =  grad(pAB, x,   y-1, z)
  95     gradBB =  grad(pBB, x-1, y-1, z)
  96     gradAA1 = grad(pAA1,x,   y,   z-1)
  97     gradBA1 = grad(pBA1,x-1, y,   z-1)
  98     gradAB1 = grad(pAB1,x,   y-1, z-1)
  99     gradBB1 = grad(pBB1,x-1, y-1, z-1)
 100     return lerp(w,
 101     lerp(v, lerp(u, gradAA, gradBA), lerp(u, gradAB, gradBB)),
 102     lerp(v, lerp(u, gradAA1,gradBA1),lerp(u, gradAB1,gradBB1)))