TempleOS has a class for 3 dimensional points consisting of F64s. HolyC is not
C++ -- it does not support passing or returning values from functions which are
not 64-bits, therefore, it can't be implemented with operator overloading.
Making all function args and returns 64-bit is a core prinicple of TempleOS.
As a courtesy, most of the CD3 functions return the addr of the destination
vect, so you can nestle calls. They do not alloc new space for the destination
vect.