Recently I am doing something about ifc4.1 with 3DE 2019x. I created an ifc4.1 alignment file, and imported it to catia. This method succeeded in many cases, but when it comes with an incomplete spiral curve, something wrong happened(see the pic). I have checked the curve created by catia, and found that the definition of the spiral curve in catia only has one radius for input, so I doubt whether the catia support incomplete spiral curve or not because the incomplete spiral curve needs two radius params!
appreciate for any help!