noise4XYBeforeZW method
4D SuperSimplex noise, with XY and ZW forming orthogonal triangular-based planes.
Recommended for 3D terrain, where X and Y (or Z and W) are horizontal. Recommended for noise(x, y, sin(time), cos(time)) trick.
Implementation
@override
double noise4XYBeforeZW(double x, double y, double z, double w) {
double s2 =
(x + y) * -0.28522513987434876941 + (z + w) * 0.83897065470611435718;
double t2 =
(z + w) * 0.21939749883706435719 + (x + y) * -0.48214856493302476942;
double xs = x + s2, ys = y + s2, zs = z + t2, ws = w + t2;
return _noise4Base(xs, ys, zs, ws);
}