It’s a fairly slow function, but it’s better than the one built into Processing.org. The functions which I don’t define are mostly in the Math library (they’re redefined like that by Processing). ‘dist’ is Euclidean distance.

int seed; //Seed for the noise. It seems that very similar seeds have very similar results.

float rr(int x,int y,int b) {

Random k = new Random(x + y*13337 + seed);

int a = 0;

while (a < b+2){

k.nextFloat(); a++;

}

return k.nextFloat();

}

int noiq = 4;//Quality of noise. Higher is slower and shouldn't have rips.

float noi(float a,float b) { //x,y positions of noise. Returns a number between 0 and 1,symmetric about 0.5.

int u = (int)floor(a-noiq);

int ut = u + noiq*2;

float s = 0;

float w = 0;

while (u < ut) {

int v = (int)floor(b-noiq);

int vt = v + noiq*2;

while (v < vt) {

float m = dist(a,b,(float)u + rr(u,v,1),(float)v + rr(u,v,2));

float j = pow(0.2,m*2);

w = w + j;

s = s + j * rr(u,v,0);

v++;

}

u++;

}

return s/w;

}