The debate over the use of computers in public education dates back to at least 1983, when the federally appointed National Commission on Excellence in Education issued its report A Nation at Risk, which harshly criticized the failures of the U.S. educational system and tied them to the nation’s economic problem: “Our once unchallenged preeminence in commerce, industry, science, and technological innovation is being overtaken by competitors throughout the world. . . . The educational foundations of our society are presently being eroded by a rising tide of mediocrity that threatens our very virtues as a Nation and a people.” The report concluded, “We must dedicate ourselves to the reform of our educational system for the benefit of all.”

The warnings of A Nation at Risk came at a time when Americans were beginning to embrace computer technology. IBM had just released the first personal computer in 1981; the company sold 6 million of them in 1983. In 1984, Apple Computer gained popularity after introducing the Macintosh, a personal computer that featured a novel, easy-to-use graphical user interface and a mouse in addition to a keyboard. The Internet and the World Wide Web would not gain popularity for another decade, but in the early 1980s Americans already felt that a social transformation was underway and that their children should be prepared for it. As the authors of A Nation at Risk put it, “Learning is the indispensable investment required for success in the ‘information age’ we are entering.”

By 1988 more than half of all workers in the United States were using computers. The nation’s school system followed this trend: According to American Prospect cofounder Paul Starr, “Between 1981 and 1991, the proportion of schools with computers rose from 18 percent to 98 percent, and the number of students per computer fell from 125 to 18.” Elementary and middle schools purchased mostly Apple computers, while high schools favored DOS-, and later, Windows-based machines. And as computer technology became more advanced, so too did the educational software that was marketed to schools. Computer-assisted education (CAI) was, and still is, touted as a potentially revolutionary new means of learning. “PCs and general applications software made computing more flexible and easily adapted to different subjects and styles of teaching,” writes Starr. He adds, “Unlike motion pictures, radio, and TV, computers were far more susceptible to both student-centered and teacher-defined activities.”

In the early 1990s, the movement to use computers in the classroom was reinvigorated by the explosive growth of the Internet and the World Wide Web. Many parents and educators hoped that the Internet would enrich CAI and the overall educational experience by connecting classrooms to the outside world. Responding to this enthusiasm, in 1996 President Bill Clinton proposed federal funding to help bring computer and Internet technology into all classrooms by 2000. Congress allotted $2 bil- lion to the Technology Literacy Fund in 1997, and this money helped bring the percentage of K–12 classrooms connected to the Internet from 3 percent in 1994 to 77 percent in 2000. Grants for integrating Internet technology into education were also a major part of the No Child Left Behind Act that President George W. Bush signed into law in January 2002.

The case for integrating computers into the classroom is summed up by a 2002 Department of Education report:

The latest research and evaluation studies demonstrate that school improvement programs that employ technology for teaching and learning yield positive results for students and teachers. Given that many schools and classrooms have only recently gained access to technology for teaching and learning, the positive outcomes of these studies suggest a future for education that could be quite bright if the nation maintains its commitment to harnessing technology for education.

The adoption of new and emerging technologies by schools and classrooms offers even more reason to be hopeful. With sufficient access and support, teachers will be better able to help their students comprehend difficult-to-understand concepts and engage in learning, provide their students with access to information and resources, and better meet their students’ individual needs. If we take advantage of the opportunities presented to us, technology will enhance learning and improve student achievement for all students.

In addition, a 2002 National Policy Association report titled Building a Digital Workforce: Confronting the Crisis emphasizes the need to train students for a computer-dominated workplace. Echoing 1983’s A Nation at Risk, the authors of Building a Digital Workforce write: “America has a workforce crisis. It has a sufficient supply of workers, but they lack adequate 21st Century IT [information technology] skills to fuel the information age economy. . . . Unless the country acts now to fill this gap, its competitiveness may be threatened.”

Yet, from its very outset in the late 1970s and early 1980s, the movement to use computers in education has had its share of critics, many of whom simply don’t believe the claims of technology enthusiasts. For technology skeptics, zealous claims about CAI echo Thomas Edison’s 1922 prediction that “The motion picture is destined to revolutionize our educational system and . . . in a few years it will supplant largely, if not entirely, the use of textbooks.” Motion pictures became primarily a media for entertainment rather than education, and critics charge that the same thing is happening to computers and the Internet.

The anti-technology viewpoint is presented in detail in books such as 1999’s High-Tech Heretic: Why Computers Don’t Belong in the Classroom and Other Reflections by a Computer Contrarian. Author Clifford Stoll argues against the conventional wisdom that students need to be computer literate to succeed in the workplace:

What jobs will be around in 2100? Surprise! They’re pretty much the same jobs available today: dentists, truck drivers, surgeons, ballet dancers, salespeople, entertainers, and school- teachers. A century from now, there will still be movies stars, morticians, gardeners, forest rangers, and police officers. . . . Curious thing about all these jobs—none of them require computing.

But the main argument used by parents, teachers, and policy makers who oppose CAI is that the money that schools spend on computers could be better used for other things, primarily hiring more teachers. This view was expressed in 1998 by the National Science Board (NSB):

The fundamental dilemma of computer-based instruction and other IT-based educational technologies is that their cost-effectiveness compared to other forms of instruction— for example, smaller class sizes, self-paced learning, peer teaching, small group learning, innovative curricula, and in-class tutors—has never been proven.

The NSB is referring to the fact that widespread use of computers in education is less than two decades old, and research on its effectiveness is largely ambiguous.

Indeed, one thing that both sides of the computers-in-education debate agree on is that more research is needed to determine what educational techniques—computer-assisted or otherwise—are most beneficial for students. As Michael Dertouzos, author of What Will Be: How the New World of Information Will Change Our Lives, puts it, “We need to continually examine what succeeds and fails, and why. And we should do so before we deploy any technical approach on a grand scale.” America’s schools are the laboratories in which educators’ many different experiments with CAI are being conducted.

The debate over computers in education is constantly evolving based on new research and technological advancements. Ultimately, decisions about whether and how to use computers in education will be made largely by individual communities and schools, based on their particular resources, needs, and goals. The viewpoints in At Issue: Computers and Education highlight the main arguments in the debate about whether CAI is good for the nation’s school system as a whole

computer education

Computer graphicsFrom Wikipedia, the free encyclopedia
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This article is about graphics created using computers. For the article about the scientific study of computer graphics, see Computer graphics (computer science). For other uses, see Computer graphics (disambiguation).

A Blender 2.45 screenshot.
A 2D projection of a 3D projection of a 4D Pentachoron performing a double rotation about two orthogonal planes.Computer graphics are graphics created using computers and, more generally, the representation and manipulation of image data by a computer.

The development of computer graphics has made computers easier to interact with, and better for understanding and interpreting many types of data. Developments in computer graphics have had a profound impact on many types of media and have revolutionized animation, movies and the video game industry.

Contents [hide]
1 Overview
2 History
2.1 Initial 1960s developments
2.2 Further 1960s developments
2.3 1970s
2.4 1980s
2.5 1990s
3 Image types
3.1 Two-dimensional
3.1.1 Pixel art
3.1.2 Vector graphics
3.2 Three-dimensional
3.3 Computer animation
4 Concepts and principles
4.1 Pixel
4.2 Graphics
4.3 Rendering
4.4 Volume rendering
4.5 3D modeling
5 Pioneers in graphic design
6 The study of computer graphics
7 Applications
8 References
9 Further reading
10 External links

[edit] OverviewThe term computer graphics has been used in a broad sense to describe "almost everything on computers that is not text or sound".[1] Typically, the term computer graphics refers to several different things:

the representation and manipulation of image data by a computer
the various technologies used to create and manipulate images
the images so produced, and
the sub-field of computer science which studies methods for digitally synthesizing and manipulating visual content, see study of computer graphics
Today, computers and computer-generated images touch many aspects of daily life. Computer imagery is found on television, in newspapers, for example in weather reports, or for example in all kinds of medical investigation and surgical procedures. A well-constructed graph can present complex statistics in a form that is easier to understand and interpret. In the media "such graphs are used to illustrate papers, reports, thesis", and other presentation material.[2]

Many powerful tools have been developed to visualize data. Computer generated imagery can be categorized into several different types: 2D, 3D, 4D, 7D, and animated graphics. As technology has improved, 3D computer graphics have become more common, but 2D computer graphics are still widely used. Computer graphics has emerged as a sub-field of computer science which studies methods for digitally synthesizing and manipulating visual content. Over the past decade, other specialized fields have been developed like information visualization, and scientific visualization more concerned with "the visualization of three dimensional phenomena (architectural, meteorological, medical, biological, etc.), where the emphasis is on realistic renderings of volumes, surfaces, illumination sources, and so forth, perhaps with a dynamic (time) component".[3]

[edit] HistoryThe phrase “Computer Graphics” was coined in 1960 by William Fetter, a graphic designer for Boeing.[4] The field of computer graphics developed with the emergence of computer graphics hardware. Early projects like the Whirlwind and SAGE Projects introduced the CRT as a viable display and interaction interface and introduced the light pen as an input device.


SAGE Sector Control Room.[edit] Initial 1960s developmentsFurther advances in computing led to greater advancements in interactive computer graphics. In 1959, the TX-2 computer was developed at MIT's Lincoln Laboratory. The TX-2 integrated a number of new man-machine interfaces. A light pen could be used to draw sketches on the computer using Ivan Sutherland's revolutionary Sketchpad software.[4] Using a light pen, Sketchpad allowed one to draw simple shapes on the computer screen, save them and even recall them later. The light pen itself had a small photoelectric cell in its tip. This cell emitted an electronic pulse whenever it was placed in front of a computer screen and the screen's electron gun fired directly at it. By simply timing the electronic pulse with the current location of the electron gun, it was easy to pinpoint exactly where the pen was on the screen at any given moment. Once that was determined, the computer could then draw a cursor at that location.

Sutherland seemed to find the perfect solution for many of the graphics problems he faced. Even today, many standards of computer graphics interfaces got their start with this early Sketchpad program. One example of this is in drawing constraints. If one wants to draw a square for example, s/he doesn't have to worry about drawing four lines perfectly to form the edges of the box. One can simply specify that s/he wants to draw a box, and then specify the location and size of the box. The software will then construct a perfect box, with the right dimensions and at the right location. Another example is that Sutherland's software modeled objects - not just a picture of objects. In other words, with a model of a car, one could change the size of the tires without affecting the rest of the car. It could stretch the body of the car without deforming the tires.

These early computer graphics were vector graphics, composed of thin lines whereas modern day graphics are Raster based using pixels.

[edit] Further 1960s developments
Spacewar! running on the Computer History Museum's PDP-1.Also in 1961 another student at MIT, Steve Russell, created the first video game, Spacewar. Written for the DEC PDP-1, Spacewar was an instant success and copies started flowing to other PDP-1 owners and eventually even DEC got a copy. The engineers at DEC used it as a diagnostic program on every new PDP-1 before shipping it. The sales force picked up on this quickly enough and when installing new units, would run the world's first video game for their new customers.

E. E. Zajac, a scientist at Bell Telephone Laboratory (BTL), created a film called "Simulation of a two-giro gravity attitude control system" in 1963.[5] In this computer generated film, Zajac showed how the attitude of a satellite could be altered as it orbits the Earth. He created the animation on an IBM 7090 mainframe computer. Also at BTL, Ken Knowlton, Frank Sindon and Michael Noll started working in the computer graphics field. Sindon created a film called Force, Mass and Motion illustrating Newton's laws of motion in operation. Around the same time, other scientists were creating computer graphics to illustrate their research. At Lawrence Radiation Laboratory, Nelson Max created the films, "Flow of a Viscous Fluid" and "Propagation of Shock Waves in a Solid Form." Boeing Aircraft created a film called "Vibration of an Aircraft."

It wasn't long before major corporations started taking an interest in computer graphics. TRW, Lockheed-Georgia, General Electric and Sperry Rand are among the many companies that were getting started in computer graphics by the mid 1960's. IBM was quick to respond to this interest by releasing the IBM 2250 graphics terminal, the first commercially available graphics computer.


Pong arcade versionRalph Baer, a supervising engineer at Sanders Associates, came up with a home video game in 1966 that was later licensed to Magnavox and called the Odyssey. While very simplistic, and requiring fairly inexpensive electronic parts, it allowed the player to move points of light around on a screen. It was the first consumer computer graphics product.

Also in 1966, Sutherland at MIT invented the first computer controlled head-mounted display (HMD). Called the Sword of Damocles because of the hardware required for support, it displayed two separate wireframe images, one for each eye. This allowed the viewer to see the computer scene in stereoscopic 3D. After receiving his Ph.D. from MIT, Sutherland became Director of Information Processing at ARPA (Advanced Research Projects Agency), and later became a professor at Harvard.

David C. Evans was director of engineering at Bendix Corporation's computer division from 1953 to 1962, after which he worked for the next five years as a visiting professor at Berkeley. There he continued his interest in computers and how they interfaced with people. In 1968 the University of Utah recruited Evans to form a computer science program, and computer graphics quickly became his primary interest. This new department would become the world's primary research center for computer graphics.

In 1967 Sutherland was recruited by Evans to join the computer science program at the University of Utah. There he perfected his HMD. Twenty years later, NASA would re-discover his techniques in their virtual reality research. At Utah, Sutherland and Evans were highly sought after consultants by large companies but they were frustrated at the lack of graphics hardware available at the time so they started formulating a plan to start their own company.

In 1969, the ACM initiated A Special Interest Group in Graphics (SIGGRAPH) which organizes conferences, graphics standards, and publications within the field of computer graphics. In 1973, the first annual SIGGRAPH conference was held, which has become one of the focuses of the organization. SIGGRAPH has grown in size and importance as the field of computer graphics has expanded over time.

[edit] 1970sMany of the most important early breakthroughs in computer graphics research occurred at the University of Utah in the 1970s. A student by the name of Edwin Catmull started at the University of Utah in 1970 and signed up for Sutherland's computer graphics class. Catmull had just come from The Boeing Company and had been working on his degree in physics. Growing up on Disney, Catmull loved animation yet quickly discovered that he didn't have the talent for drawing. Now Catmull (along with many others) saw computers as the natural progression of animation and they wanted to be part of the revolution. The first animation that Catmull saw was his own. He created an animation of his hand opening and closing. It became one of his goals to produce a feature length motion picture using computer graphics. In the same class, Fred Parke created an animation of his wife's face. Because of Evan's and Sutherland's presence, UU was gaining quite a reputation as the place to be for computer graphics research so Catmull went there to learn 3D animation.

As the UU computer graphics laboratory was attracting people from all over, John Warnock was one of those early pioneers; he would later found Adobe Systems and create a revolution in the publishing world with his PostScript page description language. Tom Stockham led the image processing group at UU which worked closely with the computer graphics lab. Jim Clark was also there; he would later found Silicon Graphics, Inc.

The first major advance in 3D computer graphics was created at UU by these early pioneers, the hidden-surface algorithm. In order to draw a representation of a 3D object on the screen, the computer must determine which surfaces are "behind" the object from the viewer's perspective, and thus should be "hidden" when the computer creates (or renders) the image.

[edit] 1980sIn the 1980s, artists and graphic designers began to see the personal computer, particularly the Commodore Amiga and Macintosh, as a serious design tool, one that could save time and draw more accurately than other methods. In the late 1980s, SGI computers were used to create some of the first fully computer-generated short films at Pixar. The Macintosh remains a highly popular tool for computer graphics among graphic design studios and businesses. Modern computers, dating from the 1980s often use graphical user interfaces (GUI) to present data and information with symbols, icons and pictures, rather than text. Graphics are one of the five key elements of multimedia technology.

[edit] 1990s3D graphics became more popular in the 1990s in gaming, multimedia and animation. In 1996, Quake, one of the first fully 3D games, was released. In 1995, Toy Story, the first full-length computer-generated animation film, was released in cinemas worldwide. Since then, computer graphics have only become more detailed and realistic, due to more powerful graphics hardware and 3D modeling software.

[edit] Image types[edit] Two-dimensional
Raster graphic sprites (left) and masks (right)2D computer graphics are the computer-based generation of digital images—mostly from two-dimensional models, such as 2D geometric models, text, and digital images, and by techniques specific to them.

2D computer graphics are mainly used in applications that were originally developed upon traditional printing and drawing technologies, such as typography, cartography, technical drawing, advertising, etc.. In those applications, the two-dimensional image is not just a representation of a real-world object, but an independent artifact with added semantic value; two-dimensional models are therefore preferred, because they give more direct control of the image than 3D computer graphics, whose approach is more akin to photography than to typography.

[edit] Pixel artPixel art is a form of digital art, created through the use of raster graphics software, where images are edited on the pixel level. Graphics in most old (or relatively limited) computer and video games, graphing calculator games, and many mobile phone games are mostly pixel art.

[edit] Vector graphics
Example showing effect of vector graphics versus raster (bitmap) graphics.Vector graphics formats are complementary to raster graphics, which is the representation of images as an array of pixels, as it is typically used for the representation of photographic images [6] Vector graphics consists in encoding information about shapes and colors that comprise the image, which can allow for more flexibility in rendering. There are instances when working with vector tools and formats is best practice, and instances when working with raster tools and formats is best practice. There are times when both formats come together. An understanding of the advantages and limitations of each technology and the relationship between them is most likely to result in efficient and effective use of tools.

[edit] Three-dimensional3D computer graphics in contrast to 2D computer graphics are graphics that use a three-dimensional representation of geometric data that is stored in the computer for the purposes of performing calculations and rendering 2D images. Such images may be for later display or for real-time viewing.

Despite these differences, 3D computer graphics rely on many of the same algorithms as 2D computer vector graphics in the wire frame model and 2D computer raster graphics in the final rendered display. In computer graphics software, the distinction between 2D and 3D is occasionally blurred; 2D applications may use 3D techniques to achieve effects such as lighting, and primarily 3D may use 2D rendering techniques.

3D computer 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 three-dimensional object. 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 two-dimensional image through a process called 3D rendering, or used in non-graphical computer simulations and calculations. There are some 3D computer graphics software for users to create 3D images.

[edit] Computer animation
Example of Computer animation produced using Motion capture
Fractal landscape, an example of computer-generated imagery. .Computer animation is the art of creating moving images via the use of computers. It is a subfield of computer graphics and animation. Increasingly it is created by means of 3D computer graphics, though 2D computer graphics are still widely used for stylistic, low bandwidth, and faster real-time rendering needs. Sometimes the target of the animation is the computer itself, but sometimes the target is another medium, such as film. It is also referred to as CGI (Computer-generated imagery or computer-generated imaging), especially when used in films.

Virtual entities may contain and be controlled by assorted attributes, such as transform values (location, orientation, and scale) stored in an object's transformation matrix. Animation is the change of an attribute over time. Multiple methods of achieving animation exist; the rudimentary form is based on the creation and editing of keyframes, each storing a value at a given time, per attribute to be animated. The 2D/3D graphics software will interpolate between keyframes, creating an editable curve of a value mapped over time, resulting in animation. Other methods of animation include procedural and expression-based techniques: the former consolidates related elements of animated entities into sets of attributes, useful for creating particle effects and crowd simulations; the latter allows an evaluated result returned from a user-defined logical expression, coupled with mathematics, to automate animation in a predictable way (convenient for controlling bone behavior beyond what a hierarchy offers in skeletal system set up).

To create the illusion of movement, an image is displayed on the computer 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.

[edit] Concepts and principlesImages are typically produced by optical devices;such as cameras, mirrors, lenses, telescopes, microscopes, etc. and natural objects and phenomena, such as the human eye or water surfaces.

A digital image is a representation of a two-dimensional image in binary format as a sequence of ones and zeros. Digital images include both vector images and raster images, but raster images are more commonly used.

[edit] Pixel
In the enlarged portion of the image individual pixels are rendered as squares and can be easily seen.In digital imaging, a pixel (or picture element[7]) is a single point in a raster image. Pixels are normally arranged in a regular 2-dimensional grid, and are often represented using dots or squares. 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 components such as red, green, and blue.

[edit] GraphicsGraphics are visual presentations on some surface, such as a wall, canvas, computer screen, paper, or stone to brand, inform, illustrate, or entertain. Examples are photographs, drawings, line art, graphs, diagrams, typography, numbers, symbols, geometric designs, maps, engineering drawings, or other images. Graphics often combine text, illustration, and color. Graphic design may consist of the deliberate selection, creation, or arrangement of typography alone, as in a brochure, flier, poster, web site, or book without any other element. Clarity or effective communication may be the objective, association with other cultural elements may be sought, or merely, the creation of a distinctive style.

[edit] RenderingRendering is the process of generating an image from a model (or models in what collectively could be called a scene file), by means of computer programs. A scene file contains objects in a strictly defined language or data structure; it would contain geometry, viewpoint, texture, lighting, and shading information as a description of the virtual scene. The data contained in the scene file is then passed to a rendering program to be processed and output to a digital image or raster graphics image file. The rendering program is usually built into the computer graphics software, though others are available as plug-ins or entirely separate programs. The term "rendering" may be by analogy with an "artist's rendering" of a scene. Though the technical details of rendering methods vary, the general challenges to overcome in producing a 2D image from a 3D representation stored in a scene file are outlined as the graphics pipeline along a rendering device, such as a GPU. A GPU is a purpose-built device able to assist a CPU in performing complex rendering calculations. If a scene is to look relatively realistic and predictable under virtual lighting, the rendering software should solve the rendering equation. The rendering equation doesn't account for all lighting phenomena, but is a general lighting model for computer-generated imagery. 'Rendering' is also used to describe the process of calculating effects in a video editing file to produce final video output.

3D projection
3D projection is a method of mapping three dimensional points to a two dimensional plane. As most current methods for displaying graphical data are based on planar two dimensional media, the use of this type of projection is widespread, especially in computer graphics, engineering and drafting.
Ray tracing
Ray tracing is a technique for generating an image by tracing the path of light through pixels in an image plane. The technique is capable of producing a very high degree of photorealism; usually higher than that of typical scanline rendering methods, but at a greater computational cost.
Shading

Example of shading.Shading refers to depicting depth in 3D models or illustrations by varying levels of darkness. It is a process used in drawing for depicting levels of darkness on paper by applying media more densely or with a darker shade for darker areas, and less densely or with a lighter shade for lighter areas. There are various techniques of shading including cross hatching where perpendicular lines of varying closeness are drawn in a grid pattern to shade an area. The closer the lines are together, the darker the area appears. Likewise, the farther apart the lines are, the lighter the area appears. The term has been recently generalized to mean that shaders are applied.
Texture mapping
Texture mapping is a method for adding detail, surface texture, or colour to a computer-generated graphic or 3D model. Its application to 3D graphics was pioneered by Dr Edwin Catmull in 1974. A texture map is applied (mapped) to the surface of a shape, or polygon. This process is akin to applying patterned paper to a plain white box. Multitexturing is the use of more than one texture at a time on a polygon.[8] Procedural textures (created from adjusting parameters of an underlying algorithm that produces an output texture), and bitmap textures (created in an image editing application) are, generally speaking, common methods of implementing texture definition from a 3D animation program, while intended placement of textures onto a model's surface often requires a technique known as UV mapping.
Anti-aliasing
Rendering resolution-independent entities (such as 3D models) for viewing on a raster (pixel-based) device such as a LCD display or CRT television inevitably causes aliasing artifacts mostly along geometric edges and the boundaries of texture details; these artifacts are informally called "jaggies". Anti-aliasing methods rectify such problems, resulting in imagery more pleasing to the viewer, but can be somewhat computationally expensive. Various anti-aliasing algorithms (such as supersampling) are able to be employed, then customized for the most efficient rendering performance versus quality of the resultant imagery; a graphics artist should consider this trade-off if anti-aliasing methods are to be used. A pre-anti-aliased bitmap texture being displayed on a screen (or screen location) at a resolution different than the resolution of the texture itself (such as a textured model in the distance from the virtual camera) will exhibit aliasing artifacts, while any procedurally-defined texture will always show aliasing artifacts as they are resolution-independent; techniques such as mipmapping and texture filtering help to solve texture-related aliasing problems.
[edit] Volume rendering
Volume rendered CT scan of a forearm with different colour schemes for muscle, fat, bone, and blood.Volume rendering is a technique used to display a 2D projection of a 3D discretely sampled data set. A typical 3D data set is a group of 2D slice images acquired by a CT or MRI scanner.

Usually these are acquired in a regular pattern (e.g., one slice every millimeter) and usually have a regular number of image pixels in a regular pattern. This is an example of a regular volumetric grid, with each volume element, or voxel represented by a single value that is obtained by sampling the immediate area surrounding the voxel.

[edit] 3D modeling3D modeling is the process of developing a mathematical, wireframe representation of any three-dimensional object, called a "3D model", via specialized software. Models may be created automatically or manually; the manual modeling process of preparing geometric data for 3D computer graphics is similar to plastic arts such as sculpting. 3D models may be created using multiple approaches: use of NURBS curves to generate accurate and smooth surface patches, polygonal mesh modeling (manipulation of faceted geometry), or polygonal mesh subdivision (advanced tessellation of polygons, resulting in smooth surfaces similar to NURBS models). A 3D model can be displayed as a two-dimensional image through a process called 3D rendering, used in a computer simulation of physical phenomena, or animated directly for other purposes. The model can also be physically created using 3D Printing devices.

[edit] Pioneers in graphic designCharles Csuri
Charles Csuri is a pioneer in computer animation and digital fine art and created the first computer art in 1964. Csuri was recognized by Smithsonian as the father of digital art and computer animation, and as a pioneer of computer animation by the Museum of Modern Art (MoMA) and Association for Computing Machinery-SIGGRAPH.
Donald P. Greenberg
Donald P. Greenberg is a leading innovator in computer graphics. Greenberg has authored hundreds of articles and served as a teacher and mentor to many prominent computer graphic artists, animators, and researchers such as Robert L. Cook, Marc Levoy, and Wayne Lytle. Many of his former students have won Academy Awards for technical achievements and several have won the SIGGRAPH Achievement Award. Greenberg was the founding director of the NSF Center for Computer Graphics and Scientific Visualization.
A. Michael Noll
Noll was one of the first researchers to use a digital computer to create artistic patterns and to formalize the use of random processes in the creation of visual arts. He began creating digital computer art in 1962, making him one of the earliest digital computer artists. In 1965, Noll along with Frieder Nake and Georg Nees were the first to publicly exhibit their computer art. During April 1965, the Howard Wise Gallery exhibited Noll's computer art along with random-dot patterns by Bela Julesz.

A modern render of the Utah teapot, an iconic model in 3D computer graphics created by Martin Newell, 1975.Other pioneers
Jim Blinn
Arambilet
Benoît B. Mandelbrot
Henri Gouraud
Bui Tuong Phong
Pierre Bézier
Paul de Casteljau
Daniel J. Sandin
Alvy Ray Smith
Ton Roosendaal
Ivan Sutherland
Steve Russell
[edit] The study of computer graphicsThe study of computer graphics is a sub-field of computer science which studies methods for digitally synthesizing and manipulating visual content. Although the term often refers to three-dimensional computer graphics, it also encompasses two-dimensional graphics and image processing.

As an academic discipline, computer graphics studies the manipulation of visual and geometric information using computational techniques. It focuses on the mathematical and computational foundations of image generation and processing rather than purely aesthetic issues. Computer graphics is often differentiated from the field of visualization, although the two fields have many similarities.

[edit] Applications Computer graphics portal
Computer Science portal
Computational biology
Computational physics
Computer-aided design
Computer simulation
Digital art
Education
Graphic design
Infographics
Information visualization
Rational drug design
Scientific visualization
Video Games
Virtual reality
Web design
[edit] References^ What is Computer Graphics?, Cornell University Program of Computer Graphics. Last updated 04/15/98. Accessed November 17, 2009.
^ University of Leeds ISS (2002). "What are computer graphics?". Last updated: 22 September 2008
^ Michael Friendly (2008). "Milestones in the history of thematic cartography, statistical graphics, and data visualization".
^ a b Wayne Carlson (2003) A Critical History of Computer Graphics and Animation. The Ohio State University
^ David Salomon (1999). Computer graphics and geometric modeling. p. ix
^ Ira Greenberg (2007). Processing: Creative Coding and Computational Art. Apress. ISBN 159059617X. http://books.google.com/books?id=WTl_7H5HUZAC&pg=PA115&dq=raster+vector+graphics+photographic&lr=&as_brr=0&ei=llOVR5LKCJL0iwGZ8-ywBw&sig=YEjfPOYSUDIf1CUbL5S5Jbzs7M8.
^ Rudolf F. Graf (1999). Modern Dictionary of Electronics. Oxford: Newnes. p. 569. ISBN 0-7506-43315. http://books.google.com/books?id=o2I1JWPpdusC&pg=PA569&dq=pixel+intitle:%22Modern+Dictionary+of+Electronics%22+inauthor:graf&lr=&as_brr=0&ei=5ygASM3qHoSgiwH45-GIDA&sig=7tg-LuGdu6Njypaawi2bbkeq8pw.
^ Blythe, David. Advanced Graphics Programming Techniques Using OpenGL. Siggraph 1999. (see: Multitexture)
[edit] Further readingJames D. Foley, Andries Van Dam, Steven K. Feiner and John F. Hughes (1995). Computer Graphics: Principles and Practice. Addison-Wesley
Donald Hearn and M. Pauline Baker (1994). Computer Graphics. Prentice-Hall.
Francis S. Hill (2001). Computer Graphics. Prentice Hall.
John Lewell (1985). Computer Graphics: A Survey of Current Techniques and Applications. Van Nostrand Reinhold.
Jeffrey J. McConnell (2006). Computer Graphics: Theory Into Practice. Jones & Bartlett Publishers.
R. D. Parslow, R. W. Prowse, Richard Elliot Green (1969). Computer Graphics: Techniques and Applications.
Peter Shirley and others. (2005). Fundamentals of computer graphics. A.K. Peters, Ltd.
M. Slater, A. Steed, Y. Chrysantho (2002). Computer graphics and virtual environments: from realism to real-time. Addison-Wesley
[edit] External links Wikimedia Commons has media related to: Computer graphics
Look up computer graphics in Wiktionary, the free dictionary.
A Critical History of Computer Graphics and Animation
History of Computer Graphics series of articles
[hide]v · d · eVisualization of technical information

Fields Biological data visualization · Chemical imaging · Crime mapping · Data visualization · Educational visualization · Flow visualization · Geovisualization · Information visualization · Mathematical visualization · Medical imaging · Molecular graphics · Product visualization · Scientific visualization · Software visualization · Technical drawing · Visual culture · Volume visualization

Image types Chart · Computer graphics · Diagram · Graph of a function · Engineering drawing · Ideogram · Information graphics · Map · Photograph · Pictogram · Plot · Spaghetti plot · Statistical graphics · Table · Technical drawings · Technical illustration

Experts Jacques Bertin · Stuart Card · Thomas A. DeFanti · Michael Friendly · Nigel Holmes · Alan MacEachren · Jock D. Mackinlay · Michael Maltz · Bruce H. McCormick · Charles Joseph Minard · Otto Neurath · William Playfair · Clifford A. Pickover · Arthur H. Robinson · Lawrence J. Rosenblum · Adolphe Quetelet · George G. Robertson · Ben Shneiderman · Edward Tufte

Related topics Cartography · Computer graphics · Graph drawing · Graphic design · Imaging science · Information science · Mental visualisation · Neuroimaging · Scientific modelling · Spatial analysis · Visual analytics · Visual perception



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Categories: Computer graphics
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