【正文】 of geometric data that is stored in the puter for the purposes of performing calculations and rendering 2D images. Such images may be for later display or for realtime viewing. Hefei university of technology math department ? 3D puter graphics are often referred to as 3D models. Apart from the rendered graphic, the model is contained within the graphical data file. However, there are differences. A 3D model is the mathematical representation of any threedimensional object (either inanimate or living). Hefei university of technology math department ? A model is not technically a graphic until it is visually displayed. Due to 3D printing, 3D models are not confined to virtual space. A model can be displayed visually as a twodimensional image through a process called 3D rendering, or used in nongraphical puter simulations and calculations. Hefei university of technology math department ? Computer animation ? Computer animation is the art of creating moving images via the use of puters. It is a subfield of puter graphics and animation. Hefei university of technology math department ? To create the illusion of movement, an image is displayed on the puter screen then quickly replaced by a new image that is similar to the previous image, but shifted slightly. This technique is identical to the illusion of movement in television and motion pictures. Hefei university of technology math department Concepts and Principles ? Image ? In mon usage, an image or picture is an artifact, usually twodimensional, that has a similar appearance to some subject—usually a physical object or a person. Hefei university of technology math department ?digital image? Hefei university of technology math department ? A digital image is a representation of a twodimensional image using ones and zeros (binary). Depending on whether or not the image resolution is fixed, it may be of vector or raster type. Without qualifications, the term digital image usually refers to raster images. Hefei university of technology math department Pixel In digital imaging, a pixel is the smallest piece of information in an image Pixels are normally arranged in a regular 2dimensional grid, and are often represented using dots or squares. Hefei university of technology math department ? Each pixel is a sample of an original image, where more samples typically provide a more accurate representation of the original. The intensity of each pixel is variable。 in color systems, each pixel has typically three or four ponents such as red, green, and blue, or cyan, magenta, yellow, and black. Hefei university of technology math department ? Graphics ? Graphics are visual presentations on some surface Hefei university of technology math department ? Examples are photographs, drawings, Line Art, graphs, diagrams, typography, numbers, symbols, geometric designs, maps, engineering drawings, or other images. Graphics often bine text, illustration, and color. Hefei university of technology math department ? Rendering ? Rendering is the process of generating an image from a model, by means of puter programs. The model is a description of three dimensional objects in a strictly defined language or data structure. Hefei university of technology math department ? 3D modelling ? 3D modeling is the process of developing a mathematical, wireframe representation of any threedimensional object via specialized software. Hefei university of technology math department Applications ? CAD ? is the use of puter technology to aid in the design and especially the drafting (technical drawing and engineering drawing) of a part or product, including entire buildings. It is both a visual (or drawing) and symbolbased method of munication whose conventions are particular to a specific technical field. Hefei university of technology math department ? Architecture, engineering, and construction (AEC) industry – Architecture – Architectural engineering – Interior design – Interior architecture – Building engineering – Civil engineering and infrastructure – Construction Hefei university of technology math department – Roads and highways – Railroads and tunnels – Water supply and hydraulic engineering – Storm drain, wastewater and sewer systems – Mapping and surveying – Chemical plant design – Factory layout – Heating, ventilation and airconditioning (HVAC) Hefei university of technology math department ? Mechanical (MCAD) engineering ? Fully editable digital multiCAD mockup – Automotive vehicles – Aerospace – Consumer goods – Machinery – Shipbuildi