gimp_drawable_curves_spline control points range.

[Ofnuts]

My own code (ofn-luminosity-masks) uses  pdb.gimp_drawable_curves_spline() with [0.0 ... 1.0] float values. Some calls are "bi" and accept either a [0.0. ... 1.0] float or a [0 ... 255] integer but I dont know if pdb.gimp_drawable_curves_spline() is among that lot.