Computer graphics relies on an internal model of the scene, that is, a mathematical representationsuitable for graphical computations.The model describes the 3D shapes, layout andmaterials of the scene.This 3D representation then has to be projected to compute a 2D image from a given viewpoint, this isthe rendering step. Rendering involves projecting the objects (perspective), handlingvisibility (which parts of objects are hidden) and computing their appearance and lighting interactions.The Birth of CGIvan Sutherland (1963) - creation of Sketchpad (received Turing Award inSketchpad was the first program is ever utilize a complete Graphical User Interface. It used a Lincoln TX-2 computerat MIT (Vector based monitor).Vector / Raster Graphics Vector graphics are composed of thin linesdrawn between coordinates. Most 70s andmid-80scomputers used vector graphics.Remember Asteroids Game.Video Games• 1961 – Steve Russell at MIT created thefirst video game, Spacewar.First Animations• 60s we start seeing various (very simple) computer generated films. Examples include Boeing’s filmcalled “Vibrations ofan Aircraft”• IBM released the IBM2250 graphics terminal, the first commercially available graphics computer !!Algorithms• The first major advances in 3D computer graphics werecreated at Utah University.John Warnock – Founder of Adobe Systems (creator ofthe PostScript page description language)• Jim Clark – Founder of Silicon Graphics Inc.1. A high quality graphics displays of personal computer provide one of the most natural means ofcommunicating with a computer.2. It has an ability to show moving pictures, and thus it is possible to produce animations with computergraphics.3. With computer graphics use can also control the animation by adjusting the speed, theportion of the total scene in view, the geometric relationship of the objects in the scene to one another,the amount of detail shown and so on.The computer graphics also provides facility called update dynamics. With update dynamics it is possibleto change the shape, color or other properties of the objects being viewed.5. With the recent development of digital signal processing (DSP) and audio synthesis chip theinteractive graphics can now provide audio feedback along with the graphical feedbacks to make thesimulated environment even more realistic.User interfaces: It is now a well established fact that graphical interfaces provide an attractive and easyinteraction between users and computers.Plotting of graphics and chart: In industry, business, government, and educational organizations,computer graphics is most commonly used to create 2D and 3Dgraphs of mathematical, physical and economic functions in form of histograms, bars and pie-charts.Computer-aided drafting and design: the computer –aided drafting uses graphics to design componentsand systems electrical, mechanical, electromechanical and electronic devices such as automobile bodies,structures of building, airplane, ships, very large scale integrated chips, optical systems and computernetworks.Simulation and Animation: use of graphics in simulation makes mathematic models and mechanicalsystems more realistic and easy to study.
Art and Commerce: There is a lot of development in the tools provided by computer graphics.Process Control: By the use of computer now it is possible to control various processes in the industryfrom a remote control room.Cartography: Computer graphics is also used to represent geographic maps, weather maps,oceanographic charts, counter maps, population density maps and so on.Education and training: computer graphics can be used to generate models of physical aids. Models ofphysical systems, physiological systems, population trends, or equipment, such as color –coded diagramcan help trainees to understand the operation of the system.Image processing: in computer graphics, a computer is used to create pictures. Image processing, on theother hands, applies techniques to modify or interpret existing picture such as photographs and scannedimage.