Installation and use

• Put the python file into scripts/addons/ directory
• Press F8 to refresh Blender
• Open the user preferences window add-ons tab
• In the add curve category, turn on the bezier curve offset tool
• In curve edit mode, select a spline(any point in spline) and press W-key-> Bezier curve offset or hotkey Ctrl+R.
• Set the value for distance and steps.