Editing Computer-aided design (section)

==Technology==
{{Unreferenced section|date=January 2020}}
[[File:cad mouse 1.svg|thumb|A CAD model of a [[Mouse (computing)|computer mouse]]]]

Originally software for CAD systems was developed with computer languages such as [[Fortran]], [[ALGOL]] but with the advancement of [[object-oriented programming]] methods this has radically changed. Typical modern [[parametric feature-based modeler]] and [[freeform surface]] systems are built around a number of key [[C (programming language)|C]] modules with their own [[application programming interface|API]]s. A CAD system can be seen as built up from the interaction of a [[graphical user interface]] (GUI) with [[NURBS]] geometry or [[boundary representation]] (B-rep) data via a [[geometric modeling kernel]]. A geometry constraint engine may also be employed to manage the associative relationships between geometry, such as wireframe geometry in a sketch or components in an assembly.

Unexpected capabilities of these associative relationships have led to a new form of [[prototyping]] called [[digital prototyping]]. In contrast to physical prototypes, which entail manufacturing time in the design. That said, CAD models can be generated by a computer after the physical prototype has been scanned using an [[industrial CT scanning]] machine. Depending on the nature of the business, digital or physical prototypes can be initially chosen according to specific needs.

Today, CAD systems exist for all the major platforms ([[Microsoft Windows|Windows]], [[Linux]], [[UNIX]] and [[Mac OS X]]); some packages support multiple platforms.<ref>{{Cite web|url=https://www.computertechreviews.com/definition/cad-workstation/|title=What is a CAD Workstation? Definition, Uses and More|date=2019-11-21|website=Computer Tech Reviews |access-date=2020-04-30}}</ref>

Currently, no special hardware is required for most CAD software. However, some CAD systems can do graphically and computationally intensive tasks, so a modern [[graphics card]], high speed (and possibly multiple) [[Central processing unit|CPU]]s and large amounts of [[Random-access memory|RAM]] may be recommended.

The human-machine interface is generally via a [[computer mouse]] but can also be via a pen and digitizing [[graphics tablet]]. Manipulation of the view of the model on the screen is also sometimes done with the use of a [[3Dconnexion|Spacemouse/SpaceBall]]. Some systems also support stereoscopic glasses for [[Scientific visualization|viewing the 3D model]]. Technologies that in the past were limited to larger installations or specialist applications have become available to a wide group of users. These include the [[Cave automatic virtual environment|CAVE]] or [[Virtual reality|HMDs]] and interactive [[Leap Motion|devices]] like motion-sensing [[Kinect|technology]]