MAE 152Computer Graphics for

Scientists and Engineers

Fall 2003

Dr. Prashant V. MahajanSenior Research Scientist

AValonRF, Inc., El Cajon, CA

What is Computer Graphics

• Computer technology used to create, manipulate and communicate visual information

ChangeImage

Reactto

Change

Graphics System User

InputDevice

Display

History of Computer Graphics• Whirlwind computer at MIT (1950s)• Sketchpad (Ivan Sutherland, MIT 1963)• Computer aided design (CAD) 1965 -• Simulators (c.1975-)• Bitmap graphical user interfaces (late 70s)• Interactive raster graphics (80s)• Virtual reality (late 80s - )• Computer animation• Visualization• Computer art• Web/internet based graphics

GC “Processes”

• Modeling

• Storing

• Manipulating

• Rendering

• Viewing

Major areas of application …

If you can imagine it, it can be done.

Major areas…entertainment

Games are okay here!

Animation

Tools for teaching and diagnosis, all the way to treatment.

Image processing

“Solid model is worth 1000 drawings !”

CAD

Scientific Visualization

Data plotting and visualization

GUI

Business Graphics

Goals of CG

• Interactivity

• Real-time

• Realism

“Distinctiveness” of CG

• Dynamic environment

• Interactive environment

• Simulation environment

• Visualizing large quantities of data

Graphics: Conceptual Model

Real Object

Human Eye

Real Light

Real Object

Human Eye

DisplayDevice

Graphics System

SyntheticModel

SyntheticCamera

SyntheticLight Source

Graphics Pipeline

z = znear

z = zfar

y

x

z

COP

y

x

zx

z

z = -1

z = 1

y

x

y

Model Coordinates Eye Coordinates Normalized Coordinates

Window CoordinatesProjectedNormalized Coordinates

ModelviewTransform

ProjectionTransform

ViewportTransform

(-1,-1)

(1,1)

glScalef() glRotatef()glTranslatef()

glFrustrum()gluPerspective()

glViewport()

How Does Application ProgramCommunicate With Graphics System?

ApplicationProgram Graphics

System

InputDevices

???2D Output Image

(3D) Model

Components of a Graphics API

• Primitive functions (What to draw)• Primitive attributes (How to draw it)• Transformation functions (Rotate, scale, translate

objects (where, how big?))• Synthetic camera Viewing functions (how to look at

it?)• Input functions (Handle interactivity)• Control functions

(Communicate with underlying window system/OS)

(Initialization, error handling, etc)

What is in this course?• OpenGL system and sample code • simple geometric modeling and GL/GLUT primitives • transformations • managing transformation stacks and composing

transformations • animation, double buffering of images • color models and representation • lights and shading models • display lists • event models and event-driven programming • standard OpenGL callbacks

What is covered …

• Matrix operations• Representations, linear functions and

interpolations, polynomials, splines, bezier functions

• ProENGINEER solid modeling• DXF (between ProE and external programs)• description of course projects and operations

Administrative

Class-hours: Wed-Fri, 5-6.20 p.m.Instructor: Dr Prashant V Mahajan

Contact: drmahajanp@hotmail.comOffice hours: Wed-Fri, 3.45-4.45 p.m.

TAs: Alex SeguritenAlex Simpkins

Textbook/Reference(1) OpenGL Programming Guide, by Neider, Davis, & Woo(2) Computer Graphics for Design, by Daniel B. Olfe(3) Handouts

Administrative …

Lab HoursAssignment / Project turn-in methodFinal QuizGrading

Assignment 1: C Programming• Learning objectives

– Review programming in C

– loops

– Variables

– Functions

– Arrays

– commenting and more

• Microsoft Visual C++ or the compiler of your choice • Basic concept of a user interface

C Programming Assignment

• Plate of heat-conductive material

• Uniform temperature for t<0

• At t=0, “point heat sources” applied at two arbitrary points on the plate

• Output the temperature distribution on the plate after 25 time steps

• Due Fri, Oct 3