Some Sonic Pi Jewels

Creations & Ideas
3

Hi there,

I worked on the Perlin Noise Music from Tachibana-san because of the copy-paste-problem as I was interested in how it sounds.
I hope, I didn’t do any mistakes, here is the code to easily copy:

def fastfloor(x)
  (x>0 ? x: x-1).to_i
end

def noise(x, y, z)
  # find unit cube that contains point
  x_ = fastfloor(x) & 255
  y_ = fastfloor(y) & 255
  z_ = fastfloor(z) & 255
  
  # find relative x, y, z of point in cube
  x-= fastfloor(x)
  y-= fastfloor(y)
  z-= fastfloor(z)
  
  # compute fade curves for each of x, y, z
  u = fade(x)
  v = fade(y)
  w = fade(z)
  
  # hash coordinates of the 8 cube corners
  a = PT[x_] + y_
  aa = PT[a] + z_
  ab = PT[a + 1] + z_
  b = PT[x_ + 1] + y_
  ba = PT[b] + z_
  bb = PT[b + 1] + z_
  
  # and add blended results from 8 corners of cube
  lerp(w, lerp(v, lerp(u, grad(PT[aa], x, y, z), grad(PT[ba], x-1, y, z)), lerp(u, grad(PT[ab], x, y-1, z), grad(PT[bb], x-1, y-1, z))), lerp(v, lerp(u, grad(PT[aa + 1], x, y, z-1), grad(PT[ba + 1], x-1, y, z-1)), lerp(u, grad(PT[ab + 1], x, y-1, z-1), grad(PT[bb + 1], x-1, y-1, z-1))));
end

def fade(t); t * t * t * (t * (t * 6-15) + 10); end
def lerp(t, a, b); a + t * (b-a); end
def grad(_hash, x, y, z)
  h = _hash & 15
  u = h<8 ? x: y
  v = h<4 ? y: ((h == 12 || h == 14) ? x: y)
  ((h & 1) == 0 ? u: -u) + ((h & 2) == 0 ? v: -v)
end

PT_PERM = [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]
PT = []; (0 ... 256).each {| i | PT[256 + i] = PT_PERM[i]; PT[i] = PT_PERM[i]}

# The above is the definition part of Perlin Noise function.
# The following is the performance part. After giving the parameters to the function, we get the random value and play.

use_random_seed Time.new.usec # <<<<<
use_synth :piano
x = rand # <<<<<
inc = 0.015 * 3 # <<<<<
loop do
  a = (noise x + inc, x, 0.0) * 20 # <<<<<
  
  a = -60 if a <-60
  puts a
  play 60 + a.to_i, sustain: 1
  sleep 0.1
  x = x + inc
end

Cu :slight_smile:

1 Like