https://math.stackexchange.com/questions/180418/calculate-rotation-matrix-to-align-vector-a-to-vector-b-in-3d
http://forums.cgsociety.org/archive/index.php?t-741227.html
https://docs.unity3d.com/ScriptReference/Vector3.RotateTowards.html
https://stackoverflow.com/questions/22924225/python-maya-rotate-y-axis-to-be-along-vector#22936535
*
https://blender.stackexchange.com/questions/69517/python-rotate-object-according-to-vectors
https://stackoverflow.com/questions/6802577/python-rotation-of-3d-vector
https://stackoverflow.com/questions/39497496/angle-between-two-vectors-3d-python
https://stackoverflow.com/questions/31735499/calculate-angle-clockwise-between-two-points
https://sites.google.com/site/mayariggingwiki/3d-math
https://www.mathsisfun.com/operation-order-pemdas.html
https://en.wikipedia.org/wiki/Linear_algebra
*
https://forums.autodesk.com/t5/maya-programming/guide-how-to-install-numpy-scipy-in-maya-windows-64-bit/td-p/5796722
https://stackoverflow.com/questions/26820714/python-find-vector-direction-between-two-3d-points
https://math.stackexchange.com/questions/293116/rotating-one-3d-vector-to-another
*
https://gamedev.stackexchange.com/questions/50963/how-to-extract-euler-angles-from-transformation-matrix
*
https://en.wikipedia.org/wiki/Aircraft_principal_axes
https://d3cw3dd2w32x2b.cloudfront.net/wp-content/uploads/2012/07/euler-angles1.pdf
http://forums.cgsociety.org/archive/index.php?t-617014.html
c-sharp
http://www.c-sharpcorner.com/UploadFile/e9fdcd/basics-of-C-Sharp/