Add orientation documentation

Co-authored-by: Andrew Barrett-Sprot <abarrettsprot@gmail.com>

Author: trickeydan

docs/source/_static/api/vision/m-45x0y0z.png

@@ -84,6 +84,9 @@ You can access the position using ``m.bearing`` and ``m.distance``.
        print(m.bearing)  # Bearing to the marker from the origin, in radians
        print(m.distance)  # Bearing to the marker from the origin, in radians
 
+* ``m.bearing`` is equivalent to ``m.position.cylindrical.phi``.
+* ``m.distance`` is equivalent to ``m.position.cylindrical.p``.
+
 For further information on position, including how to use ``m.position`` and the coordinate systems,
 see `Position <position.html>`__.
 

docs/source/_static/api/vision/m0x-45y0z.png

@@ -1,3 +1,63 @@
 Orientation
 ===========
 
+.. figure:: /_static/api/vision/yawpitchroll.png
+   :alt: Yaw Pitch and Roll
+   :scale: 80%
+
+   Yaw Pitch and Roll (Image source: Peking University)
+
+Orientation represents the rotation of a marker around the x, y, and z axes. These can be accessed as follows:
+
+* ``rot_x`` / ``pitch`` - the angle of rotation in radians counter-clockwise about the Cartesian x axis.
+* ``rot_y`` / ``yaw`` - the angle of rotation in radians counter-clockwise about the Cartesian y axis.
+* ``rot_z`` / ``roll`` - the angle of rotation in radians counter-clockwise about the Cartesian z axis.
+
+Rotations are applied in order of z, y, x.
+
+.. code:: python
+
+   markers = r.camera.see()
+
+   for m in markers:
+       print(m.orientation.rot_x)  # Angle of rotation about x axis.
+       print(m.orientation.rot_y)  # Angle of rotation about y axis.
+       print(m.orientation.rot_z)  # Angle of rotation about z axis.
+
+.. Note:: In our use case the z axis always faces the camera, and thus will appear as a clockwise rotation
+
+Examples
+--------
+
+The following table visually explains what positive and negative rotations represent.
+
++----------------------------+-----------------------------+
+|        0 in all axes       |          |m0x0y0z|          |
++--------------+-------------+---------------+-------------+
+| π/4 in rot_x | |m-45x0y0z| | -π/4 in rot_x | |m-45x0y0z| |
++--------------+-------------+---------------+-------------+
+| π/4 in rot_y |  |m0x45y0z| | -π/4 in rot_y | |m0x-45y0z| |
++--------------+-------------+---------------+-------------+
+| π/4 in rot_z |  |m0x0y45z| | -π/4 in rot_z | |m0x0y-45z| |
++--------------+-------------+---------------+-------------+
+
+.. |m0x0y0z| image:: /_static/api/vision/m0x0y0z.png
+    :scale: 30%
+
+.. |m0x0y45z| image:: /_static/api/vision/m0x0y45z.png
+    :scale: 30%
+
+.. |m0x0y-45z| image:: /_static/api/vision/m0x0y-45z.png
+    :scale: 30%
+
+.. |m0x45y0z| image:: /_static/api/vision/m0x45y0z.png
+    :scale: 30%
+
+.. |m0x-45y0z| image:: /_static/api/vision/m0x-45y0z.png
+    :scale: 30%
+
+.. |m45x0y0z| image:: /_static/api/vision/m45x0y0z.png
+    :scale: 30%
+
+.. |m-45x0y0z| image:: /_static/api/vision/m-45x0y0z.png
+    :scale: 30%