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Computer Graphics Essay Research Paper Computer GraphicsTable

Computer Graphics Essay, Research Paper


Computer Graphics


Table of Contents


Introduction 3


How It Was 3


How It All Began 4


Times Were Changing 6


Industry’s First Attempts 7


The Second Wave 10


How the Magic is Made 11


Modeling 12


Animation 13


Rendering 13


Conclusion 15


Bibliography 16


Introduction


Hollywood has gone digital, and the old ways of doing things are dying. Animation and special effects created with computers have been embraced by television networks, advertisers, and movie studios alike. Film editors, who for decades worked by painstakingly cutting and gluing film segments together, are now sitting in front of computer screens. There, they edit entire features while adding sound that is not only stored digitally, but also has been created and manipulated with computers. Viewers are witnessing the results of all this in the form of stories and experiences that they never dreamed of before. Perhaps the most surprising aspect of all this, however, is that the entire digital effects and animation industry is still in its infancy. The future looks bright.


How It Was


In the beginning, computer graphics were as cumbersome and as hard to control as dinosaurs must have been in their own time. Like dinosaurs, the hardware systems, or muscles, of early computer graphics were huge and ungainly. The machines often filled entire buildings. Also like dinosaurs, the software programs or brains of computer graphics were hopelessly underdeveloped. Fortunately for the visual arts, the evolution of both brains and brawn of computer graphics did not take eons to develop. It has, instead, taken only three decades to move from science fiction to current technological trends. With computers out of the stone age, we have moved into the leading edge of the silicon era. Imagine sitting at a computer without any visual feedback on a monitor. There would be no spreadsheets, no word processors, not even simple games like solitaire. This is what it was like in the early days of computers. The only way to interact with a computer at that time was through toggle switches, flashing lights, punchcards, and Teletype printouts.


How It All Began


In 1962, all this began to change. In that year, Ivan Sutherland, a Ph.D. student at (MIT), created the science of computer graphics. For his dissertation, he wrote a program called Sketchpad that allowed him to draw lines of light directly on a cathode ray tube (CRT). The results were simple and primitive. They were a cube, a series of lines, and groups of geometric shapes. This offered an entirely new vision on how computers could be used. In 1964, Sutherland teamed up with Dr. David Evans at the University of Utah to develop the world’s first academic computer graphics department. Their goal was to attract only the most gifted students from across the country by creating a unique department that combined hard science with the creative arts. They new they were starting a brand new industry and wanted people who would be able to lead that industry out of its infancy. Out of this unique mix of science and art, a basic understanding of computer graphics began to grow. Algorithms for the creation of solid objects, their modeling, lighting, and shading were developed. This is the roots virtually every aspect of today’s computer graphics industry is based on. Everything from desktop publishing to virtual reality find their beginnings in the basic research that came out of the University of Utah in the 60’s and 70’s. During this time, Evans and Sutherland also founded the first computer graphics company. Aptly named Evans & Sutherland (E&S), the company was established in 1968 and rolled out its first computer graphics systems in 1969. Up until this time, the only computers available that could create pictures were custom-designed for the military and prohibitively expensive. E&S’s computer system could draw wireframe images extremely rapidly, and was the first commercial “workstation” created for computer-aided design (CAD). It found its earliest customers in both the automotive and aerospace industries.


Times Were Changing


Throughout its early years, the University of Utah’s Computer Science Department was generously supported by a series of research grants from the Department of Defense. The 1970’s, with its anti-war and anti-military protests, brought increasing restriction to the flows of academic grants, which had a direct impact on the Utah department’s ability to carry out research. Fortunately, as the program wound down, Dr. Alexander Schure, founder and president of New York Institute of Technology (NYIT), stepped forward with his dream of creating computer-animated feature films. To accomplish this task, Schure hired Edwin Catmull, a University of Utah Ph.D., to head the NYIT computer graphics lab and then equipped the lab with the best computer graphics hardware available at that time. When completed, the lab boasted over $2 million worth of equipment. Many of the staff came from the University of Utah and were given free reign to develop both two- and three-dimensional computer graphics tools. Their goal was to soon produce a full -length computer animated feature film. The effort, which began in 1973, produced dozens of research papers and hundreds of new discoveries, but in the end, it was far too early for such a complex undertaking. The computers of that time were simply too expensive and too under powered, and the software not nearly developed enough. In fact, the first full length computer generated feature film was not to be completed until recently in 1995. By 1978, Schure could no longer justify funding such an expensive effort, and the lab’s funding was cut back. The ironic thing is that had the Institute decided to patent many more of its researcher’s discoveries than it did, it would control much of the technology in use today. Fortunately for the computer industry as a whole, however, this did not happen. Instead, research was made available to whomever could make good use of it, thus accelerating the technologies development.


Industry’s First Attempts


As NYIT’s influence started to wane, the first wave of commercial computer graphics studios began to appear. Film visionary George Lucas (creator of Star Wars and Indiana Jones trilogies) hired Catmull from NYIT in 1978 to start the Lucasfilm Computer Development Division, and a group of over half-dozen computer graphics studios around the country opened for business. While Lucas’s computer division began researching how to apply digital technology to filmmaking, the other studios began creating flying logos and broadcast graphics for various corporations including TRW, Gillette, the National Football League, and television programs, such as “The NBC Nightly News” and “ABC World News Tonight.” Although it was a dream of these initial computer graphics companies to make movies with their computers, virtually all the early commercial computer graphics were created for television. It was and still is easier and far more profitable to create graphics for television commercials than for film. A typical frame of film requires many more computer calculations than a similar image created for television, while the per-second film budget is perhaps about one-third as much income. The actual wake-up call to the entertainment industry was not to come until much later in 1982 with the release of Star-Trek II: The Wrath of Kahn. That movie contained a monumental sixty seconds of the most exciting full-color computer graphics yet seen. Called the “Genesis Effect,” the sequence starts out with a view of a dead planet hanging lifeless in space. The camera follows a missiles trail into the planet that is hit with the Genesis Torpedo. Flames arc outwards and race across the surface of the planet. The camera zooms in and follows the planets transformation from molten lava to cool blues of oceans and mountains shooting out of the ground. The final scene spirals the camera back out into space, revealing the cloud-covered newly born planet. These sixty seconds may sound uneventful in light of current digital effects, but this remarkable scene represents many firsts. It required the development of several radically new computer graphics algorithms, including one for creating convincing computer fire and another to produce realistic mountains and shorelines from fractal equations. This was all created by the team at Lucasfilm’s Computer Division. In addition, this sequence was the first time computer graphics were used as the center of attention, instead of being used merely as a prop to support other action. No one in the entertainment industry had seen anything like it, and it unleashed a flood of queries from Hollywood directors seeking to find out both how it was done and whether an entire film could be created in this fashion. Unfortunately, with the releas

e of TRON later that same year and The Last Starfighter in 1984, the answer was still a decided no. Both of these films were touted as a technological tour-de-force, which, in fact, they were. The films’ graphics were extremely well executed, the best seen up to that point, but they could not save the film from a weak script. Unfortunately, the technology was greatly oversold during the film’s promotion and so in the end it was technology that was blamed for the film’s failure. With the 1980s came the age of personal computers and dedicated workstations. Workstations are minicomputers that were cheap enough to buy for one person.


Smaller was better, aster, an much, much cheaper. Advances in silicon chip technologies brought massive and very rapid increases in power to smaller computers along with drastic price reductions. The costs of commercial graphics plunged to match, to the point where the major studios suddenly could no longer cover the mountains of debt coming due on their overpriced centralized mainframe hardware. With their expenses mounting, and without the extra capital to upgrade to the newer cheaper computers, virtually every independent computer graphics studio went out of business by 1987. All of them, that is, except PDI, which went on to become the largest commercial computer graphics house in the business and to serve as a model for the next wave of studios.


The Second Wave


Burned twice by TRON and The Last Starfighter, and frightened by the financial failure of virtually the entire industry, Hollywood steered clear of computer graphics for several years. Behind the scenes, however, it was building back and waiting for the next big break. The break materialized in the form of a watery creation for the James Cameron 1989 film, The Abyss. For this film, the group at George Lucas’ Industrial Light and Magic (ILM) created the first completely computer-generated entirely organic looking and thoroughly believable creature to be realistically integrated with live action footage and characters. This was the watery pseudopod that snaked its way into the underwater research lab to get a closer look at its human inhabitants. In this stunning effect, ILM overcame two very difficult problems: producing a soft-edged, bulgy, and irregular shaped object, and convincingly anchoring that object in a live-action sequence. Just as the 1982 Genesis sequence served as a wake-up call for early film computer graphics, this sequence for The Abyss was the announcement that computer graphics had finally come of age. A massive outpouring of computer-generated film graphics has since ensued with studios from across the entire spectrum participating in the action. From that point on, digital technology spread so rapidly that the movies using digital effects have become too numerous to list in entirety. However they include the likes of Total Recall, Toys, Terminator 2: Judgment Day, The Babe, In the Line of Fire, Death Becomes Her, and of course, Jurassic Park.


How the Magic is Made


Creating computer graphics is essentially about three things: Modeling, Animation, and Rendering. Modeling is the process by which 3-dimensional objects are built inside the computer; animation is about making those objects come to life with movement, and rendering is about giving them their ultimate appearance and looks. Hardware is the brains and brawn of computer graphics, but it is powerless without the right software. It is the software that allows the modeler to build a computer graphic object, that helps the animator bring this object to life, and that, in the end, gives the image its final look. Sophisticated computer graphics software for commercial studios is either purchased for $30,000 to $50,000, or developed in-house by computer programmers. Most studios use a combination of both, developing new software to meet new project needs.


Modeling


Modeling is the first step in creating any 3D computer graphics. Modeling in computer graphics is a little like sculpting, a little like building models with wood, plastic and glue, and a lot like CAD. Its flexibility and potential are unmatched in any other art form. With computer graphics it is possible to build entire worlds and entire realities. Each can have its own laws, its own looks, and its own scale of time and space. Access to these 3-dimensional computer realities is almost always through the 2-dimensional window of a computer monitor. This can lead to the misunderstanding that 3-D modeling is merely the production perspective drawings. This is very far from the truth. All elements created during any modeling session possess three full dimensions and at any time can be rotated, turned upside down, and viewed from any angle or perspective. In addition, they may be re-scaled, reshaped, or resized whenever the modeler chooses. Modeling is the first step in creating any 3-dimensional computer animation. It requires the artist’s ability to visualize mentally the objects being built, and the craftsperson’s painstaking attention to detail to bring it to completion. To create an object, a modeler starts with a blank screen an sets the scale of the computer’s coordinate system for that element. The scale can be anything from microns to light years across in size. It is important that scale stays consistent with all elements in a project. A chair built in inches will be lost in a living room built in miles. The model is then created by building up layers of lines and patches that define the shape of the object.


Animation


While it is the modeler that contains the power of creation, it is the animator who provides the illusion of life. The animator uses the tools at his disposal to make objects move. Every animation process begins essentially the same way, with a storyboard. A storyboard is a series of still images that shows how the elements will move and interact with each other. This process is essential so that the animator knows what movements need to be assigned to objects in the animation. Using the storyboard, the animator sets up key points of movements for each object in the scene. The computer then produces motion for each object on a frame by frame basis. The final result when assembled, gives the form of fluid movement.


Rendering


The modeler gives form, the animator provides motion, but still the animation process is not complete. The objects and elements are nothing but empty or hollow forms without any surface. They are merely outlines until the rendering process is applied. Rendering is the most computational time demanding aspect of the entire animation process. During the rendering process, the computer does virtually all the work using software that has been purchased or written in-house. It is here that the animation finally achieves its final look. Objects are given surfaces that make it look like a solid form. Any type of look can be achieved by varying the looks of the surfaces. The objects finally look concrete. Next, the objects are lighted. The look of the lighting is affected by the surfaces of the objects, the types of lights, and the mathematical models used to calculate the behavior of light. Once the lighting is completed, it is now time to create what the camera will see. The computer calculates what the camera can see following the designs of the objects in the scene. Keep in mind that all the objects have tops, sides, bottoms, and possibly insides. Types of camera lens, fog, smoke, and other effects all have to be calculated. To create the final 2-D image, the computer scans the resulting 3D world and pulls out the pixels that the camera can see. The image is then sent to the monitor, to videotape, or to a film recorder for display. The multiple 2D still frames, when all assembled, produce the final animation.


Conclusion


Much has happened in the commercial computer graphics industry since the decline of the first wave of studios and the rise of the second. Software and hardware costs have plummeted. The number of well-trained animators and programmers has increased dramatically. And at last, Hollywood and the advertising community have acknowledged that the digital age has finally arrived, this time not to disappear. All these factors have lead to an explosion in both the size of existing studios and the number of new enterprises opening their doors. As the digital tide continues to rise, only one thing is certain. We have just begun to see how computer technology will change the visual arts.


BIBLIOGRAPHY


How Did They Do It? Computer Illusion in Film & TV , Alpha Books 1994; Christopher W. Baker


Computer Graphics World, Volume 19, Number 3; March 1996; Evan Hirsch, “Beyond Reality”


Computer Graphics World, Volume 19, Number 4; April 1996; Evan Marc Hirsch, “A Changing Landscape”


Windows NT Magazine, Issue #7, March 1996; Joel Sloss, “There’s No Business Like Show Business”


Cinescape, Volume 1, Number 5; February 1995; Beth Laski, “Ocean of Dreams”

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