// https://stackoverflow.com/questions/1171849/finding-quaternion-representing-the-rotation-from-one-vector-to-another
public static __rot3t__ HalfWayVec(__v3t__ from, __v3t__ into)
{
if (from.Dot(into).ApproximateEquals(-1))
{
return(new __rot3t__(0, from.AxisAlignedNormal()));
}
else
{
__v3t__ half = Vec.Normalized(from + into);
__quatt__ q = new __quatt__(Vec.Dot(from, half), Vec.Cross(from, half));
return(new __rot3t__(q.Normalized));
}
}
public static __rot3t__ HalfWayQuat(__v3t__ from, __v3t__ into)
{
var d = Vec.Dot(from, into);
if (d.ApproximateEquals(-1))
{
return(new __rot3t__(0, from.AxisAlignedNormal()));
}
else
{
__quatt__ q = new __quatt__(d + 1, Vec.Cross(from, into));
return(new __rot3t__(q.Normalized));
}
}
public static __rot3t__ Original(__v3t__ from, __v3t__ into)
{
var angle = from.AngleBetween(into);
//# var rotIntoEps = isDouble ? "1e-15" : "1e-6f";
if (angle < __rotIntoEps__)
{
return(__rot3t__.Identity);
}
else if (__pi__ - angle < __rotIntoEps__)
{
return(new __rot3t__(0, from.AxisAlignedNormal()));
}
else
{
__v3t__ axis = Vec.Cross(from, into).Normalized;
return(__rot3t__.Rotation(axis, angle));
}
}