Error in GeomConvert_ApproxCurve

[chenkasirer]

I am attempting to serialize the brep created in this example using compas.data.json_dump but getting the following error:

Traceback (most recent call last):
    ...
    json_dump(C, PATH, pretty=True)
  File "C:\Users\ckasirer\.conda\envs\occ\lib\site-packages\compas\data\json.py", line 41, in json_dump
    return json.dump(data, f, cls=DataEncoder, **kwargs)
  File "C:\Users\ckasirer\.conda\envs\occ\lib\json\__init__.py", line 179, in dump
    for chunk in iterable:
  File "C:\Users\ckasirer\.conda\envs\occ\lib\json\encoder.py", line 438, in _iterencode
    o = _default(o)
  File "C:\Users\ckasirer\.conda\envs\occ\lib\site-packages\compas\data\encoders.py", line 102, in default
    value = o.to_data()
  File "C:\Users\ckasirer\.conda\envs\occ\lib\site-packages\compas\data\data.py", line 248, in to_data
    return self.data
  File "c:\users\ckasirer\repos\compas_occ\src\compas_occ\brep\brep.py", line 163, in data
    faces.append(face.data)
  File "c:\users\ckasirer\repos\compas_occ\src\compas_occ\brep\brepface.py", line 101, in data
    boundary = self.loops[0].data
  File "c:\users\ckasirer\repos\compas_occ\src\compas_occ\brep\breploop.py", line 56, in data
    edges.append(edge.data)
  File "c:\users\ckasirer\repos\compas_occ\src\compas_occ\brep\brepedge.py", line 120, in data
    convert = GeomConvert_ApproxCurve(
  File "C:\Users\ckasirer\.conda\envs\occ\lib\site-packages\OCC\Core\GeomConvert.py", line 717, in __init__
    _GeomConvert.GeomConvert_ApproxCurve_swiginit(self, _GeomConvert.new_GeomConvert_ApproxCurve(*args))
TypeError: Wrong number or type of arguments for overloaded function 'new_GeomConvert_ApproxCurve'.
  Possible C/C++ prototypes are:
    GeomConvert_ApproxCurve::GeomConvert_ApproxCurve(opencascade::handle< Geom_Curve > const &,Standard_Real const,GeomAbs_Shape const,Standard_Integer const,Standard_Integer const)
    GeomConvert_ApproxCurve::GeomConvert_ApproxCurve(opencascade::handle< Adaptor3d_HCurve > const &,Standard_Real const,GeomAbs_Shape const,Standard_Integer const,Standard_Integer const)

To Reproduce

Run the following code

    from compas.geometry import Point, Vector, Plane
    from compas.geometry import Box, Cylinder
    from compas_occ.brep import BRep

    R = 1.4
    P = Point(0, 0, 0)
    X = Vector(1, 0, 0)
    Y = Vector(0, 1, 0)
    Z = Vector(0, 0, 1)
    YZ = Plane(P, X)
    ZX = Plane(P, Y)
    XY = Plane(P, Z)

    box = Box.from_width_height_depth(2 * R, 2 * R, 2 * R)
    cx = Cylinder((YZ, 0.7 * R), 4 * R)
    cy = Cylinder((ZX, 0.7 * R), 4 * R)
    cz = Cylinder((XY, 0.7 * R), 4 * R)

    A = BRep.from_box(box)
    B1 = BRep.from_cylinder(cx)
    B2 = BRep.from_cylinder(cy)
    B3 = BRep.from_cylinder(cz)

    C = A - (B1 + B2 + B3)

    json_dump(C, PATH, pretty=True)

Expected behavior

The Brep should be serialized.

Desktop (please complete the following information):

• OS: Windows 10
• CPython 3.9

[chenkasirer]

Some more info:

This is due to this call to GeomConvert_ApproxCurve() in BRepEdge.data

convert = GeomConvert_ApproxCurve(self.curve, 1e-3, GeomAbs_Shape.GeomAbs_C1, 1, 5)

Seems there's some issue with the types of the arguments being sent. I initially thought this is due to sending self.curve which is of type compas_occ.geometry.OCCCurve whereas Geom_Curve is expected, but sending the underlying self.curve.occ_curve doesn't work either.

Generally, I wasn't able to successfully call GeomConvert_ApproxCurve() which in turn calls _GeomConvert.new_GeomConvert_ApproxCurve(*args). Hard to debug further because it's passed to the C binding from there on.

PyCharm seems to thing the issue is the GeomAbs_Shape.GeomAbs_C1 as it indicates that I'm sending an int rather than the Enum type, but not sure if that's really the issue, and in any case not sure how to do it differently.

[tomvanmele]

the use of GeomConvert_ApproxCurve was an attempt to always convert to NURBS without any further checks. it seems that this doesn't really work. so we will have to go back to the more elaborate setup of checking curve types and doing specific conversions.

will update...

[tomvanmele]

going to close this, even though not entirely solved yet, since the code has changed quite a bit in the meantime...