public void SetSeed(int seed)
{
this.seed = seed;
PerlinNoise.SetSeed(seed);
UnityEngine.Debug.Log(String.Format("World seed: {0}", seed));
}
public static double GenerateRidged(double x, double y, double z, double H, double lacunarity,
double octaves, double offset, double gain)
{
double result;
double frequency;
double signal;
double weight;
int i;
// precompute and store spectral weights
if (first)
{
// seize required memory for exponent_array
exponentArray = new double[(int)octaves + 1];
frequency = 1.0f;
for (i = 0; i <= octaves; i++)
{
// compute weight for each frequency
exponentArray[i] = Math.Pow(frequency, -H);
frequency *= lacunarity;
}
first = false;
}
// get first octave
signal = PerlinNoise.Generate(x, y, z);
// get absolute value of signal (this creates the ridges)
if (signal < 0.0)
{
signal = -signal;
}
// invert and translate (note that "offset" should be ~= 1.0)
signal = offset - signal;
// square the signal, to increase "sharpness" of ridges
signal *= signal;
// assign initial values
result = signal;
weight = 1.0;
for (i = 1; i < octaves; i++)
{
// increase the frequency
x *= lacunarity;
y *= lacunarity;
z *= lacunarity;
// weight successive contributions by previous signal
weight = signal * gain;
if (weight > 1.0)
{
weight = 1.0;
}
if (weight < 0.0)
{
weight = 0.0;
}
signal = PerlinNoise.Generate(x, y, z);
if (signal < 0.0)
{
signal = -signal;
}
signal = offset - signal;
signal *= signal;
// weight the contribution
signal *= weight;
result += signal * exponentArray[i];
}
return(result);
}
