All spline smoothers are derived from a common base class, spline_smoother::SplineSmoother. Each derived class just overrides a single method: spline_smoother::SplineSmoother::smooth(). These smoothers are "filters" (filters::FilterBase), so they can be dynamically loaded from a library file, and a chain of such filters can be instantiated from an XML file using filters::FilterChain.
There are currently three implementations of smoothers in the library. Detailed documentation for each of these is available in the code API:
Additionally, splines.h contains some useful functions for converting back and forth between waypoints and spline coefficients, and for sampling from cubic and quintic splines.
This package is just a library and does not have any ROS nodes.