(2020-11-02, 17:04)Magnus Forsberg Wrote: The first, and last, condline in a cyli have a controlpoint on the tangential plane to the cylinder.
When 2 cyli primitives are placed next to each other these condlines will complement each other.
This also explains why an author have to add an extra complementary condline if a surface is not placed in the tangential plane.
Thanks Magnus. That clears it up, including why I couldn't make sense of combining primitives for 3/4 cylinders and such.