computer graphics - department of aerospace engineering

Computer Graphics

Dr. S.M. MalaekAssistant: M. Younesi

Computer Graphics

Introduction to Computer Graphics, Anirban Mukhopadhyay, ArupChattopadhyay

COMPUTER GRAPHICS, Donald Haern, M. Pauline Baker (Second Edition)

روشهاي مدلسازي در محيط مجازي كامپيوتر، دكتر سيدمحمدباقر ملائك، معصومه يونسي

Textbook:Sunday/Tuesday 13:30-15Time:

Modeling

Computers have become a powerful tool for the rapid and economical production of pictures and models.

There is no area in which graphics displays cannot be used to some advantage.

What is Computer Graphics?

Computer graphics generally means creation, storage and manipulationof models and images.

What is Computer Graphics?

Such models come from diverse and expanding set of fields including physical, mathematical, artistic, biological, economical, … .

Model

Model, models, or modeling: a pattern, plan, representation, or description designed to show the structure or working of an object, system, or concept.

Physical Model

Physical Model

A physical model is used to mean a physical representation of some things, for example a bolt or the solar system.

Physical Model

A scale model of the Singapore City Centre.

The geometry of the model and the object it represents are often similar in the sense that one is a rescaling of the other.

Physical Model

Model of a war scene.

Physical Model

Model of molecule.

Physical Model

Cuddly toy

Mathematical Model

Mathematical ModelA mathematical mode: it uses mathematical language to describe the behaviour of a system.

Mathematical models are used in the science, engineering, economics and …

Mathematical Model

Examples:Population Growth

Model of a particle in a potential field.

Mathematical Model

A mathematical model describes a system by a set of variables and a set of equations that establish relationship between the variables.

Economics Model

Economic Model

In economics, a model is a theoretical construct that represents economic processes by a set of variables and a set of logical and quantitative relationships between them.

Economic Model

Economic models have two function:

Simplification

Selection

What is Computer Graphics?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 cockpitdesign, using 3D model of human body.

What is Computer Graphics?“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.”

What is Interactive Computer Graphics?

User controls contents, structure, and appearance of objects and their displayed images via rapid visual feedback.

Interactive Computer GraphicsBasic components of an interactive graphics system:

input (e.g., mouse, tablet and stylus, scanner…)processing (and storage)display/output (e.g., screen, paper-based printer, video recorder …)

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.

Interactive Computer Graphics

Before Sketchpad, output via plotters/printers, input via keypunch.

Card punching. IBM 704 . took up a whole room and was capable of about 4,000 arithmetic operations/second.


“The Sketchpad system uses drawing as a novel communication medium for a computer. The system contains input, output, and computation programs which enable it to interpret information drawn directly on a computer display. ”


“Sketchpad has shown the most usefulness as an aid to the understanding of processes, such as the motion of linkages, which can be described with pictures. Sketchpad also makes it easy to draw highly repetitive or highly accurate drawings and to change drawings previously drawn with it…”


Three factors be considered:

Time

Cost

Quality


Interactive Computer GraphicsCost/Time ($/hr): 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. Today, commodity PCs perform approximately two or three billion operations/second.

Quality: Eliminates error propagation by using data bases and transfer of data.


Applications

Computer Aided DesignPresentation GraphicsComputer ArtEntertainmentEducation and trainingVisualizationImage ProcessingGraphics User Interfaces

Applications Computer Aided Design

(CAD)

ApplicationsComputer Aided Design (CAD)

A major use of computer graphics in design processes, particularly for engineering and architectural system. But almost all product are now computer designed.


For some design applications, objects are first displayed in a wireframeoutline form.

Wireframe (outline) form shows the overall shape and internal features of objects.


CAD methods are now used in the design of:

Buildings


Automobiles


Aircraft


Watercraft


SpacecraftTextiles…


Software package for CAD applications typically provide the designer with a multi-window environment.


Circuits designed by successively placing components into the layout, with the graphics package automatically providing the connections between components.


Animation are often used in CAD applications.

Animation in virtual reality environment are used to determine how system operators are affected by certain motion.


Virtual Reality (VR)Fishtank VR


The manufacturing process is also tied in to the computer description of designed objects to automate the construction of the product.


Architectural Designs


Rug Pattern

Applications

Presentation Graphics

ApplicationsPresentation Graphics

Presentation graphics used to product illustrations for reports or to generate 35-mm slides or transparencies for use with projectors.


Presentation graphics is used to:StatisticalMathematicalScientificEconomic dataManagerial reportConsumer information bulletins


Typical examples of presentation graphics are:

Bar GraphsLine GraphsSurface GraphsPie Charts


Typical examples of presentation graphics are:

HistogramTask Schedule ChartInventory ChartProduction Chart


Bar Charts


Line Graphs

0

5

10

15

20

25

30

1 2 3 4

Series1Series2Series3


Surface Graphs


Pie Charts


Histogram: A histogram is the graphical version of a able which shows what property of cases fall into each of several or many specified categories.


Task Scheduling chart: In project management, a schedule consists of a list of a project’s terminal elements with intended start and finish dates.


Production Chart


Export Chart

Applications

Computer Art

ApplicationsComputer Art

Computer graphics are widely used in both fine art and commercial artapplications.


Fine ArtPaintbrush Program:It allows artists to “paint” pictures on the screen of a video monitor.


Example of Paintbrush Methods:


Commercial ArtLogosPage layout (Combining text and graphics)

TV Advertising Spots


Commercial ArtAdvertising


Commercial ArtMorphing: Where one object is transformed (metamorphosed) into another.


Commercial ArtMorphing

Applications

Entertainment

ApplicationsEntertainment

Computer graphics are now commonly used in making motion pictures, music video, and television shows.


TV Shows


Games

Applications

Education and Training

ApplicationsEducation and Training

Models of physical systems, physiological systems, population trends can help trainees to understand the operation of the system.


For some training applications, special systems are designed.

Color-coded diagram used to explain the operation of a nuclear reactor.


Special systems are the simulators for practice session or training of ship captains, aircraft pilots, and air traffic control personnel.


Flight Simulator


Naval Simulator

Applications

Visualization

ApplicationsVisualization

Producing graphical representation for scientific, engineering, and medical data sets and processes is generally referred to as scientific visualization.The term business visualization is used in connection with data sets related to commerce, industry, and other nonscientific areas.


A Color-coded with 16 million density points of relative brightness.


Visualisation Techniques for Architecture


Distribution of galaxies


Visualisation of confocal microscope data


Mathematical data.


Medical data.


Medical Data


Mars renderings

Applications

Image Processing

ApplicationsImage Processing

Image processing applies techniques to modify or interpret existing pictures, such as photographs and TV scans.

Medicine uses these techniques to model and study physic functions, to artificial limbs, and to plan and practice surgery.

ApplicationsImage Processing

Medical Visualization

ApplicationsGraphics User Interfaces


A major component of a graphical interface is a window manager that allows a user to display multi-window areas.


Interfaces also display menus and icons for fast selection of processing options or parameter values.

An icon is a graphical symbol that is designed to look like the processing option it represent.

computer graphics - department of aerospace engineering

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