In some cases it is not possible to create a correct model of a real environment or complex object in a reasonable amount of time or to an appopriate degree of accuracy. Techniques and methods have been developed to enable us to create 3D models from real place and objects. Below are a couple of commonly used examples.

Laser Scanning

Laser scanning can be done on a large scale, to scan building and rooms with their contents. or on a small scale, to scan a small object on a platform. The scanning device rotates sampling the distance a laser beam travels until it hits a surface. The locations relative to the scanner are stored and a cloud of points is created which can be transformed into a polygonal model using specialised software.

Photogammetry

Objects can also be created using photographs as a starting point and resulting in a texture mapped object. There are various methods available for doing this. Some systems attempt to interpret the images and generate geometry and textures, whereas others rely on the user to create geometry manually using the photographs as a guide for positioning and identify points (e.g. the corners of a box) in pictures taken at different angles.