Documentation for b-spline in Part Workbench

[Charles]

OS: Ubuntu 14.04.1 LTS
Word size: 64-bit
Version: 0.14.3702 (Git)
Branch: releases/FreeCAD-0-14
Hash: b3368125c63289ec8ce9faec2b2ae4c78d436406
Python version: 2.7.6
Qt version: 4.8.6
Coin version: 4.0.0a
SoQt version: 1.6.0a

I have seen some tantalizing bits of code using splines in the part workbench
(from http://www.freecadweb.org/wiki/index.ph ... ectellipse):

def execute(self, fp):
r1=fp.a
r2=fp.b
s=fp.n
z=0.0
p=1.0
####w=2**0.5/2.0 #Ellipse
w=2**0.5/2.0/(1-s**p)
curve=Part.BSplineCurve()
curve.setPeriodic()
curve.increaseDegree(2) #quadratic
curve.insertKnots([i*1.0/(4) for i in (1,2,3)],[2]*(3)) #5Knots 8 Poles
curve.setPole(1,FreeCAD.Vector(0,-r2,z),1)
curve.setPole(2,FreeCAD.Vector(-r1,-r2,z),w)
curve.setPole(3,FreeCAD.Vector(-r1,0,z),1)
curve.setPole(4,FreeCAD.Vector(-r1,r2,z),w)
curve.setPole(5,FreeCAD.Vector(0,r2,z),1)
curve.setPole(6,FreeCAD.Vector(r1,r2,z),w)
curve.setPole(7,FreeCAD.Vector(r1,0,z),1)
curve.setPole(8,FreeCAD.Vector(r1,-r2,z),w)
if fp.createFace == True:
fp.Shape = Part.Face(Part.Wire(curve.toShape()))
else:
fp.Shape = curve.toShape()

I've been using the Spyder IDE for debugging and code experimentation. I've been able to get
Part.Part.BSplineCurve() to create a <BSplineCurve object>. It doesn't take any args in the
construction, however, and the above code looks like one has to create the <BSplineCurve object>,
then specify it. I don't find any documentation in the wiki, forums, internet search for how to do this
in the Part Workbench. Searches only appear to turn up Draft Workbench examples, which allow one
to specify the details at the time of construction, thus a different beastie, it seems.

Is there any detailed documentation of how the b-spline works in the Part Workbench, or do I just
need to experiment until I figure out how the commands work?

[mario52]

hi
here one macro with Part.BSplineCurve()
one discussion Closed BSplines with Same First & Last Point
the wiki page of Draft_BSpline an one example of macro
mario