BSPLINE_DELETE_INTERPOLATION_POINT deletes interpolation points in a specified interpolation B-spline.
---->(BSPLINE_DELETE_INTERPOLATION_POINT)----|B-spline|----+ | +--------------------------<---------------------------+ | v +------------<------------+ | | | +--+--|interpolation point|--+---->
BSPLINE_DELETE_INTERPOLATION_POINT [pick interpolation point]