Study on General Geometrical Modeling of Single Yarn with 3D Twist Effect

This paper presents a general method for modeling a 3D photorealistic single yarn for the construction of a fabric structure composed of the yarn with different types of cross sections. Various types of cross sections can be designed by using a quasi-uniform quadratic B-spline curve. The central line of the yarn is designed by a sequence of key control points to form a shape-preserving quasi-uniform cubic B-spline curve. The control grid of the B-spline surface for the single yarn is based on the combination of the quadratic and cubic curve. With random turbulence and proper assemblage of the cross sections, a realistic 3D twist effect for the single yarn is achieved. The simulated pictures of the yarns and fabrics indicate that this general and flexible model can be applied to the simulation of various 3D geometrical structures of yarns and then extended to fabrics.