@SuperDicq yes it is just yaw pitch and roll when expressed on euclidean planes. BUT it is not possible to express rotations as a set of pitch->yaw->roll or else gimbal locks occur in the math.

nature doesn't gimbal lock, and they had to come up with spinors and shit because some particles rotate 360 or 900 degrees and it's apparently important to note that a 360 noscope boson is NOT the same as a 0 rotation boson.

i don't know what the fourth dimension does. in quaternions it's just an imaginary number that is part of the computation until its cancelled to be rendered in 3D again.

in clifford geometric algebra the fourth dimension is a trivector representing the XYZ hyperplane in conjunction with individual positions on the XY, XZ and ZY basis planes.