split surface Geom_Surface - multiple approaches

Hi everyone!

I'm trying to split surfaces by curves and get a resulting surface. I need this surface (Geom_BsplineSurface) to extract geometric parameters like the knot vectors and control polygon. I approached this in different ways but never with a satisfying result. I present you the approaches I took and show you how I implemented them. Additionally I attached a file with examples for all my approaches.

--- What I tried:

1. Geom_RectangularTrimmedSurface only trims by U,V. I want an arbitrary cutting edge so this is not a solution for me.

2. GEOMAlgo_Splitter does not work with my compiled OCE-12 and pythonOCC master (also tried 0.6-dev, 0.6-beta, 0.6-alpha with OCE-11). I always receive a segmentation fault when executing Perform(). Maybe I'm not using the splitter correctly.
I also tried to implement the GEOMAlgo_Splitter in c++ but had the problem that the algorithm got stuck. I added a cpp file with a GEOMAlgo_Splitter example in the next post which gets stuck for me. I looked into the sources in geom-6.3.1.8.: I followed the execution trail and found, that the execution gets stuck at PaveFiller from NMTTools_PaveFiller. It seems that not all necessary methods/functions like PreparePaveBlocks are defined. In geom-6.3.1.8/src/NMTTools there are multiple NMTTools_PaveFiller_*.cpp files and some of them have the necessary methods/function. I'm by far no expert in C++ - how this makes sense is beyond my knowledge...

3. BRepAlgoAPI_Section - creates intersections between shapes. Works great but I do not want an intersecting curve but a split surface.

4. BRepAlgoAPI_Cut - also creates intersections even when set to Operation(cut)

5. BRepFeat_SplitShape works great as I can split my original shape (created from the surface) into sub shapes via a projected curve(edge). My problem here is to convert the resulting shapes to Geom_Surface. Conversion results in surfaces that are the same as the original surfaces.

My main question is:
How can I get surfaces from the resulting shapes?

Best regards
Kay

--- following short detail of example code - python
see the attached file for a working example including geometry generation pythonOCC

# ###### GEOMAlgo_Splitter

aFace_orig = makeFace(handle_sweptSurface_trimmed_bsplinesurf)
aFace_cutter = makeFace(handle_sweptSurface_cutter_trimmed_bsplinesurf)

# instantiate the Splitter
splitter_Algo = GEOMAlgo_Splitter()
# add the shape to be split
splitter_Algo.AddShape(aFace_orig)
# add the shape that works as a cutter
splitter_Algo.AddTool(aFace_cutter)
# run splitter
splitter_Algo.Perform() # segmentation fault here

# resulting shape
result_shape = splitter_Algo.Shape()

# ###### BRepAlgoAPI_Cut

aFace_orig = makeFace(handle_sweptSurface_trimmed_bsplinesurf)
aFace_cutter = makeFace(handle_sweptSurface_cutter_trimmed_bsplinesurf)

# instantiate the cutter
cutter = BRepAlgoAPI_Cut(aFace_orig,aFace_cutter)
# generate results
cutter.Build()
# get the result
ResultShape = cutter.Shape()

--> does not result in splitted shapes

# ###### BRepFeat_SplitShape

# instantiate the splitter and add the cutter
splitter = BRepFeat_SplitShape(aFace_orig)
splitter.Add(aEdge_cutter,aFace_orig)
# build result
splitter.Build()
# iterator for the result objects
iter = TopTools_ListOfShape()
iter.Set(splitter.Modified(aFace_orig))
# get the results
shape = iter.First()
shape_other_edge = iter.Last()

# convert a shape to a face
face_shape_other_edge = TopoDS.face(shape_other_edge) # # generate a surface from the shape
surf = BRep_Tool.Surface(face_shape_other_edge) #

--> does not result in a splitted surface