Computer Graphics Introduction I
A Survey of Computer Graphics • What is computer graphics? • Interactive computer graphics • The history of computer graphics • Computer graphics applications • Device
What is Computer Graphics? • Some possible definitions: • Approaches, Methods, Technics and Tools for virtual world visualization • Generating 2D images of a 3D world represented in computer • Main tasks • Modeling: construct the 3D model of the scene • Rendering: compute the color of each pixel • Animation
What is Computer Graphics? (1/2) Computer graphics generally means creation, storage and manipulation of models and images Such models come from diverse and expanding set of fields including physical, mathematical, artistic, biological, and even conceptual (abstract) structures Frame from animation by William Latham, shown at SIGGRAPH 1992. Latham uses rules that govern patterns of natural forms to create his artwork.
William Fetter coined term “computer graphics” in 1960 to describe new design methods he was pursuing at Boeing Created a series of widely reproduced images on pen plotter exploring cockpit design, using 3D model of human body. What is Computer Graphics? (2/2) “Perhaps the best way to define computer graphics is to find out what it is not. It is not a machine. It is not a computer, nor a group of computer programs. It is not the know-how of a graphic designer, a programmer, a writer, a motion picture specialist, or a reproduction specialist. Computer graphics is all these – a consciously managed and documented technology directed toward communicating information accurately and descriptively.” Computer Graphics, by William A. Fetter, 1966
What is Interactive Computer Graphics? (1/3) User controls contents, structure, and appearance of objects and their displayed images via rapid visual feedback Basic components of an interactive graphics system input (e.g., mouse, tablet and stylus, force feedback device, scanner, live video streams…) processing (and storage) display/output (e.g., screen, paper-based printer, video recorder, non-linear editor…) First truly interactive graphics system, Sketchpad, pioneered at MIT by Ivan Sutherland for his 1963 Ph.D. thesis Sketchpad in 1963. Note use of a CRT monitor, light pen and function-key panel.
Before Sketchpad, output via plotters/printers, input via keypunch, both in batch What is Interactive Computer Graphics? (2/3) Batch (1950s – now) Card punching (left). IBM 704 (right) took up a whole room and was capable of about 4,000 arithmetic operations/second. Cool facts: Whirlwind, built in early 50’s at MIT, cost $4.5 million and could perform 40,000 additions/second. Mac 512K, list price $3,195 in 1984, could do 500,000.
Modeling Modeling with Maya
Modeling Modeling from image
Modeling The tree model (a) without leaves (b) with leaves
Rendering Indirect diffusion Caustic effect
Rendering “A Rapid Hierarchical Rendering Technique for Translucent Materials”. Jensen, Siggraph’2002
Questions • Graphics Vs. Image ? - geometric elements and attributes - pixel arrays • Computer Graphics Vs. Image Processing • CG : 3D Models ->rendering -> images • I. P : 2D images ->analysis->models(other information, special effects...)
The History of Computer Graphics Pioneer: Ivan Sutherland 1963: Sutherland’s PhD Thesis：“Sketchpad: A Man-machine Graphical Communications System.”, MIT,1963 First time used“Computer Graphics”. CG started to be a novel and independent scientific branch.
Pioneer：Ivan Sutherland • First truly interactive graphics system, Sketchpad, pioneered at MIT by Ivan Sutherland for his 1963 Ph.D. thesis Sketchpad in 1963. Note use of a CRT monitor, light pen and function-key panel.
The History of Computer Graphics • Poineer: Ivan Sutherland • 1962: Pierre Bezier put forward “Bezier curve” for the representation of space curve • 1967: Wylie added lighting effect in objects representation • 1969: Xerox developed GUI (Graphic User Interface) • 1973: Richard Shoup invented Raster-Scan Display • The great improvement of graphic techniques • Phong lighting model(1973)；Texture mapping(1974)；Ray tracing(1980)；Radiosity(1984)…
The History of Computer Graphics • Industry • ILM(Industrial Light and Magic): an Academy Award winning motion picture visual effects company, 1975 • SGI (Silicon Graphics, Inc): 1982 • Pixar 1986 • AutoDesk, Adobe • Display card • 1994: the first PC display card --- by 3DLabs • 1995.11: Voodoo --- by 3DFx • 1999: Geforce256, the first GPU --- by nVidia • nVidia and ATI • Geforce 8800、Radeon HD 2900 XT
The History of Computer Graphics • Graphics Standard • GKS(Germany, 1970’s); PHIGS(ISO, 1986); GKS-3D(1988) • OpenGL(SGI, 1992); DirectX(Microsoft); Java3D(Sun) • Graphics Application Software • 3DS Max, Maya, LightWave 3D • Renderman • AutoCAD, Solid Work
Computer Graphics Applications • Computer Aided Design/Manufacturing • Entertainment • Education&Science and Training • Visualization in Scientific Computing • Graphical User Interface • ……
Computer Aided Design/Manufacturing (CAD/CAM) • Computer aided design in airplane, car, watercraft, architecture, costume, toy…
CAD/CAM • Boeing 777(1990.10 – 1994.4) • All the designing work is in computer graphics stations and terminals • No paper • Boeing 747(comparing) • 16320 meters paper!
CAD/CAM Computer aided design/Manufacturing in airplane
CAD/CAM Computer aided architecture design
CAD/CAM Computer aided design in shoe Manufacturing
Entertainment • Movies, Animations • Games • NPR (Non-Photorealistic Rendering) • ……
Special Effects in Movie Jurassic Park（1993）
Special Effects in Movie Titanic (1997)
3D Animation Movie Toy story (1995) Monster’s Inc. (2001)
3D Animation Movie Hair Skin Final Fantasy (2001)
Toon Shading NPR (Non-Photorealistic Rendering) Calligraphy generated using computers
Education & Science and Training • Computer Aided Education and Science • Computer simulating the phenomenon in biology, geography, physics, chemistry, medicine, political social, economy and other sciences • Computer Aided Training • System for training of ship captains, aircraft pilots …
Computer Graphics in Geography • Terrain Generation NMT Fractal models Aerial views Landsat
Visualization in Scientific Computing • Producing graphical representations for scientific, engineering and medical data sets and processes
Application --- Hydrodynamic The air current around a car
Application --- Weather The isolines exhibit the distribution of atmospheric pressure http://www.ssec.wisc.edu/~billh/vis5d.html
Application --- Medical The visible human project
Graphical User Interface(GUI) 3D operating system
Graphic Devices in Computer System • CPU • CPU implements all kinds of computations about graphics such as description, construction and modification • GPU(Graphic Processing Unit) • Video Display Devices • Input Devices