public float EvaluateTriCubic(int x, int y, int z, RandomSeed r)
{
float value = 0f;
for (int d = 2; d < degreeAtKPosMax; d++)
{
int range = Mathf.FloorToInt(Mathf.Pow(2f, degreeAtKPosMax - d));
int x0 = (x / range) * range;
int y0 = (y / range) * range;
int z0 = (z / range) * range;
float xd = (float)(x % range) / (float)range;
float yd = (float)(y % range) / (float)range;
float zd = (float)(z % range) / (float)range;
float[][][] f = new float[4][][];
for (int i = 0; i < 4; i++)
{
f[i] = new float[4][];
for (int j = 0; j < 4; j++)
{
f[i][j] = new float[4];
for (int k = 0; k < 4; k++)
{
f[i][j][k] = r.Rand(x0 + (i - 1) * range, y0 + (j - 1) * range, z0 + (k - 1) * range, d);
}
}
}
float[][] fz = new float[4][];
for (int i = 0; i < 4; i++)
{
fz[i] = new float[4];
for (int j = 0; j < 4; j++)
{
fz[i][j] = TERP(zd, f[i][j][0], f[i][j][1], f[i][j][2], f[i][j][3]);
}
}
float[] fy = new float[4];
for (int i = 0; i < 4; i++)
{
fy[i] = TERP(yd, fz[i][0], fz[i][1], fz[i][2], fz[i][3]);
}
float fx = TERP(xd, fy[0], fy[1], fy[2], fy[3]);
value += fx / Mathf.FloorToInt(Mathf.Pow(2f, d - 2));
}
// Note : value belongs to [-1.5f ; +1.5f]
value = (value + 1.5f) / 3f;
this.minValue = Mathf.Min(this.minValue, value);
this.maxValue = Mathf.Max(this.maxValue, value);
this.valuesCount++;
this.valuesSum += value;
return(value);
}
static public float EvaluateBiCubic(int x, int y, RandomSeed r)
{
int degree = 13;
float value = 0f;
for (int d = 8; d < degree; d++)
{
int range = Mathf.FloorToInt(Mathf.Pow(2f, degree - d));
int x0 = (x / range) * range;
int y0 = (y / range) * range;
float xd = (float)(x % range) / (float)range;
float yd = (float)(y % range) / (float)range;
float[][] f = new float[4][];
for (int i = 0; i < 4; i++)
{
f[i] = new float[4];
for (int j = 0; j < 4; j++)
{
f[i][j] = r.Rand(x0 + (i - 1) * range, y0 + (j - 1) * range, d);
}
}
float[] fy = new float[4];
for (int i = 0; i < 4; i++)
{
fy[i] = TERP(yd, f[i][0], f[i][1], f[i][2], f[i][3]);
}
float fx = TERP(xd, fy[0], fy[1], fy[2], fy[3]);
value += fx / Mathf.FloorToInt(Mathf.Pow(2f, d - 8));
}
// Note : value belongs to [-2f ; +2f]
return((value + 2f) / 4f);
}