#http://www.scratchapixel.com/lessons/procedural-generation-virtual-worlds/procedural-patterns-noise-part-1/simple-pattern-examples

pixels = W:512 H:512

x = from 0 to 8 W
y = from 0 to 8 H

k = xor_gradient_fbm2(x, y)

r = sin( x + k*10*PI)*0.5 + 0.5
g = r
b = r
