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About your question:
What you are trying to do can be and should be done with a Python generator object, since such tasks are its main use case. Cinema 4D does however not provide an auto-triangulation routine in the Python generator, like you might be used to from the various plotting environments out there, e.g.
Mathematica/Wolfram. The Python generator is not a plotting tool, but a pruned version of an
ObjectData plugin, allowing you to build arbitrary shapes (at the cost of not having an automesher like provide by
matplotlib.mplot3d for example). Cinema does also not support complex numbers as point coordinates, since its vector space is exclusively
R³ - at least for polygon objects. You can however use Python's
complex module if you want to deal with complex numbers and then map these into
Below you will find the code for your example and also a file with a Python generator in it, running that code.
# Your vertex data expressed as c4d.Vector instances.
VERTEX_DATA = [
c4d.Vector(1, 1, 1), c4d.Vector(1, 1, -1),
c4d.Vector(0, 0, 1), c4d.Vector(0, 0, -1),
c4d.Vector(-1, 1, 1), c4d.Vector(-1, 1, -1),
SCALE = 100.
# Create a polygon object node setup for 6 vertices and 2 polygons.
node = c4d.PolygonObject(pcnt=6, vcnt=2)
# Your data is rather small, so we have to scale it a bit up.
points = [p * SCALE for p in VERTEX_DATA]
# Set all points.
# Now we have to create the polygons which are represented by CPolygon in
# Cinema 4D. Cinema has no rectangular auto-mesher which will
# automatically triangulate a point cloud provided in a certain way, like
# for example provided by matplotlib in Python, Mathematica/Wolfram or
# similar math packages.
# In this case we could iterate in a convenient fashion over our data
# due to its regular nature. I will doe it however manually for clarity.
# The first polygon: CPolygon references point indices in its attributes
# a, b, c and d. In Cinema all non-gons are represented by CPolygon,
# including triangles, which just repeat their third index in d.
# We index our vertices here. The a bit odd index order is caused by
# how you did provide your data. Polygons are organized ccw for forward-
# facing normals in Cinema, read more about it here .
cpoly = c4d.CPolygon(0, 1, 3, 2)
# Then we add the first polygon to our mesh.
# Now we do the same with the second polygon. We have to reindex the
# vertices 2 and 3 here, since they are shared by both polygons.
cpoly = c4d.CPolygon(2, 3, 5, 4)
# And we are done and can return our little wedge shape.
#  https://developers.maxon.net/docs/Cinema4DPythonSDK/html/manuals/3d_concept/modeling/polygon_object.html#polygon-object