A coordinate frame: an origin, a normal (its z axis) and a direction (its x axis, square to the
normal); its y axis is the normal crossed with the direction, so the frame is right-handed. A
frame places things: shapes land on it, profiles are drawn in its plane.
A coordinate frame: an origin, a normal (its z axis) and a direction (its x axis, square to the normal); its y axis is the normal crossed with the direction, so the frame is right-handed. A frame places things: shapes land on it, profiles are drawn in its plane.