Problem: There is not a straightforward way to go from the initial tangent
twist to the perpendicular twist without changing the twist value of each
Control Point by 90 degrees.
In this revision users have three new Twist Methods in the Curve's Object
Data Properties Tab. Users can now choose "Y-Up", "X-Up", and "Normal"
Twist Methods from the pull-down menu in addition to the options that
were previously supported (Z-Up, Minimum, and Tangent).
The Y-Up and X-Up twist methods work similarly to the Z-Up method, but
will use the corresponding orthogonal axis. The Normal twist method is
just a 90-degree twist from the tangent Twist method. This could be
achieved through an addon. I chose to add these options here though
because they provide a useful basis set of initial twist settings.
Examples:
New Twist Modes
Normal Twist Mode:
Y-Up Twist Mode:
X-Up Twist Mode:
Previous Twist Modes:
Z-Up Twist Mode:
Minimum Twist Mode:
Tangent Twist Mode:
