public static uint select(uint src, Part16x4 part) => Bits.gather(src, (uint)part);
public static T project<T>(uint src, Part16x4 part)
where T : unmanaged
=> convert<T>(project(src,part));
public static uint ToScalar(this Part16x4 src) => (uint)src;
public static uint project(uint src, Part16x4 part)
=> Bits.scatter(src, (uint)part);