Based on C3D©FairCurveModeler, universal and specialized applications are developed on the platforms of CAD systems and mathematical systems. The article shows an approach to structuring applications that provides the possibility of invariant use of the same COM-component in all applications. This structure makes it easy to migrate the application from the AutoCAD platform to the BricsCAD platform. The command for constructing the Sectrix of Maclaurin in C3D©FairCurveModeler is improved. Formulas for calculating the first and second derivatives are determined. B-spline curve of the 8th degree is isogeometrically constructed on the Hermite geometric determinant. A third order algebraic curve (cubic curve) is explored with the aim of using it to model high quality curves in C3D©FairCurveModeler. A program is developed for calculating the cubic curve equation at 9 points and displaying it as a dense set of curve points. The possibility of isogeometric construction of a cubic curve on a polyline of 9 points is shown, subject to weak restrictions on the shape of the polyline. Plans are made for the further development of cubic curve based methods

Fair Curves, FairCurveModeler, C3D©

Muftejev V.G.,  muftejev@mail.ru,  orcid.org/0000-0003-4352-3381,  C3D Labs

Ziganshina F.T.,  fairusa85@mail.ru,  Ufa State Petroleum Technological University

Gumerov V.I.,  Ufa State Petroleum Technological University