Techniques

Polygonal modelling. Many three dimensional models are created as textured polygonal models. Polygonal modelling is a method of creating a 3D model by connecting line segments through points in a 3D space. These points in space are also known as vertices. Polygonal models are very flexible and can be rendered by a computer very quickly. One cannot, however, create an exact curved surface using polygonal 3D modelling technique.

Primitive modelling. This is the simplest way of modelling three dimensional objects. Using geometric primitives such as cylinders, cones, cubes and spheres, complex models are created. This approach ensures easy construction as the forms are mathematically defined and precise. Primitive modelling is mainly used in developing 3D models of technical applications.

NURBS modelling. The NURBS (Non-uniform rational B-spline) modelling method can be found in popular software like Maya. The developer can create smooth-surfaced 3D models using this modelling technique. Unlike polygonal modelling techniques which can only approximate curved surfaces using numerous polygons, NURBs modelling can truly create smooth curved surfaces.

Splines and patches modelling. These methods are similar to the NURBS modelling procedure. They depend on curved lines to identify the visible surface.

3D modelling can be easily performed using dedicated software such as Maya, and 3DS Max. There are also some scene description languages like POV-Ray which are used for modelling. While most three dimensional software suites are priced very high, open source programs are available for free. Most programs follow polygonal and NURBS modelling methods to create models. For modelling complicated materials like rain, clouds and blowing sands, the programs employ a particle system to make the modelling process easier.

Today, 3D modelling is employed in a wide variety of activities. The video game industry uses various three dimensional modelling methods to create realistic character models for video games. In the medical field, detailed models of human body organs are created using various advanced 3D modelling software. The engineering community uses 3D computer aided design (CAD) programs to create three dimensional models of new devices, vehicles and structures.