Understanding NURBS Modeling technique in 3D Modeling
NURBS or Non-Uniform Rational B-splines use a method of mathematically describing curves and surfaces that are well suited to 3D applications or art works. NURBS could be considered as equations used to define curves or surfaces that simulate the designer’s batten in terms of stiffness and continuity. During early 1970’s B or Basis splines were created (infinite number of splines) as a convenient way to define smooth curves and surfaces interactively on the computer screen. The designer changes the shape of the curve by changing the positions of the defining vertex point.
Over and above polygon techniques, NURBS are characterized by the smooth organic forms they product. Surfaces under NURBS can be very quickly edited and modeled using variety of techniques. NURBS surfaces are shaped using one of more NURBS curves that defines the base outline of the form that a designer wants for a surface & then using explicit building method to create the finished surface. Art forms or designs where smooth forms with minimal data are required to define a particular form as in case of industrial and automotive designs; the designers prefer to use NURBS curves and surfaces. Apart from this NURBS curves and surfaces have many other preferred applications like defining a smooth motion path for an animated object. Also with NURBS a surface can be modeled and then transformed to poly mesh. Yet another method for creating NURBS surfaces is to loft a series of curves that define the cross section of the designer’s desired surface form. Lofting a surface works like stretching a skin over each of the cross sections to create the final desired surface.
As highlighted above in addition to just creating NURBS surfaces using curves, designers can edit and sculpt surfaces and primitive objects using the Sculpt surface tool. Sculpt surface tool offers all the functionalities of digital sculpting and allows designer to interactively push or pull on the surface regions to create areas that are embossed or in relief in relation to the surface.