What do you mean. Um. " reference frames " ?
It 's called a
uh uh
It 's  it 's spatial reference frames. You actually have only  Um. If you wanna have a  This is usually um  I should  there should be an " L " , though. Well actually you have  only have two choices. You can either do a two - point or a three - point which is you You 're familiar with th with the " origo " ? where that 's the center  " Origo " is the center of the f frame of reference.