If closed is set to True the last point will be connected to the first point.
epsilon is a threshold value that determines the accuracy of length calculations of the curve.
subdiv is the number of subdivisions that are made to draw the curve using OpenGL.
If show_tangents is set to True the OpenGL visualization will also show the in and out tangents.
You can also pass a previously created BezierCurveGeom object via the curvegeom argument. In this case, the arguments pnts, closed, epsilon, subdiv and show_tangents are ignored.