Friday, August 19, 2011

3 D Modeling

3D modeling is the process of developing a mathematical representation of a three-dimensional surface of any object (either inanimate or living). This is done in computers using software capable of rendering 3D computer graphics and is also known as meshing. The final product is called a 3D model. It can either be displayed in the form of a two-dimensional image through a process called 3D rendering or used as it is in a computer simulation of physical phenomena. 3D Printing services actually allow the model to be physically created. Models may be created either automatically or manually. The manual modeling process is very similar to plastic arts such as sculpting.

Almost all 3D models can be broadly divided into two categories.
  • Solid - These models are a representation of the volume of the object(such as a rock) that they represent. These are more realistic representations, but are more difficult to build. Solid models are mostly used for specialized visual applications viz. ray tracing and constructive solid geometry and nonvisual simulations such as medical and engineering simulations.
  • Shell/boundary - These models are a representation of the surface (viz. the boundary) of an object, not its volume. For example, for an infinitesimally thin eggshell this model comes handy. These are also easier to work with than solid models. Shell models are commonly used for visual models that are used in games and films.

Boundary representations are common in computer graphics since the appearance of an object depends largely on its exterior. Two dimensional surfaces make a good representation for the objects used in graphics. Polygonal meshes (and also to some extent subdivision surfaces) are by far the most common representation for a discrete digital approximation of surfaces that are not finite. Point-based representations have also been gaining some popularity in recent years. Deforming surfaces which undergo many topological changes, such as fluids, are best represented by level sets. The 5 popular ways to represent a model are: Polygonal modeling, NURBS, Splines and patches, primitives modeling, and sculpt modeling. There are a number of modeling techniques, including constructive solid geometry, implicit surfaces, and subdivision surfaces. These are used for shaping individual objects for the scene.
Article Source: http://www.ArticleBlast.com
About The Author:

Jack Watson writes content on 3D Modeling for more information please visit :- http://www.designpresentation.com/