normalizeFast method
Approximation of quaternion normalization. Works best when quat is already almost-normalized. @author unphased, https://github.com/unphased
Implementation
Quaternion normalizeFast(){
final f = (3.0 - (x * x + y * y + z * z + w * w)) / 2.0;
if (f == 0) {
x = 0;
y = 0;
z = 0;
w = 0;
} else {
x *= f;
y *= f;
z *= f;
w *= f;
}
return this;
}