Builds the pipe identifier id
generated by the base line, which is the horizontal circle 24 sides and radius 100 moved vertically 13 times on
the generator which is the line segment (0,100,0, 0,-100,0).
close: the surface is closed, it will be automatically closed if the base is close to eps (0.1 default).
poi(base): the baseline is base=x1,y1,z1,...
poi(gen): the generating line is gen=x1,y1,z1,...
precision(p): accuracy of the closure.
The surface is generated by the base curve moved normally to the gen curve.
Properties can be specified at creation.