CS602 Official Handouts

Table of Contents

Graphics Systems I ..............................................................................25 Graphics Systems II ............................................................................34 Point ......................................................................................................43 Line Drawing Techniques...................................................................53 Circle Drawing Techniques ................................................................59 Ellipse and Other Curves....................................................................64 Filled-Area Primitives-I ......................................................................78 Filled-Area Primitives-II.................................................................. Mathematics Fundamentals.............................................................1 Lecture No..11 2D Transformations I..........................................................................121 2D Transformations II.......................................................................125 Drawing Example...............................................................................1 Clipping-I............................................................................................1 Clipping-II..........................................................................................14 3D Concepts.......................................................................................1 3D Transformations I........................................................................1 3D Transformations II......................................................................1 Projections..........................................................................................1  Perspective Projection....................................................................... Triangles and Planes.........................................................................2 Triangle Rasterization......................................................................21 Lighting I............................................................................................2 Lighting II..........................................................................................2 Mathematics of Lighting and Shading Part I.................................24

Mathematics of Lighting and Shading Part II Light Types and

Shading Models..................................................................................2 Review II............................................................................................2 Review III...........................................................................................26 Mathematics of Lighting and Shading Part III..............................2 Mathematics of Lighting and Shading Part IV..............................2  Mathematics of Lighting and Shading Part V................................29 Introduction to OpenGL................................................................... OpenGL Programming - I.................................................... ............3 OpenGL Programming - II..............................................................3 Curves.................................................................................................32 Space Curves......................................................................................3 The Tangent Vector...........................................................................3 Bezier Curves.....................................................................................3 Building Polygonal Models of Surfaces...........................................34 Fractals...............................................................................................3 Viewing...............................................................................................3 Examples of Composing Several Transformations........................3  Real-World and OpenGL Lighting.................................................. Evaluators, curves and Surfaces......................................................4 Animations.........................................................................................4

1.1 Definition

Computers accept process, transform and present information.

Computer Graphics involves technology to accept, process, transform and present information in a visual form that also concerns with producing images (or animations) using a computer.

Q1. 2 Why Study Computer Graphics?

There are certain important reasons to study computer graphics. We will discuss them under certain heads:

Visualization

I like to see what I am doing. Many a times it happens that you perform certain tasks which you cannot visualize; for example as a student of data structures, you implement trees, graphs and other Abstract Data Types (ADTs) but you cannot visualize them whereas you must be having an inner quest to see what these actually look like.

I like to show people what I am doing. Similarly at certain times you would be performing certain tasks which you know but it would be difficult for others to understand them so there is very important requirement of showing the things in order to make them understandable.

Graphics is interesting

We are visual creatures and for us a picture is worth a thousand words. If we can get rid of text based static screen and get some graphics; it’s always interesting to see things in colours and motion on the screen. Therefore graphics is interesting because it involves simulation, algorithm, and architecture.

Requirement

Well there are certain areas which require use of computer graphics heavily. One example is drawing of machines. It is required to prepare drawing of a machine before the actual production. The other heavy requirement is for architects as they have to prepare a complete blue print of the building they have to build long before the actual construction work gets underway. AutoCAD and other applications of the kind are heavily used today for building architecture.

Merely a couple of decades back, the idea of a 24 hours Cartoons Network was really a far fetched one. That was the time when one would wait for a whole week long before getting an entertainment of mere 15 minutes. Well thanks to computer graphics that have enabled us to entertain ourselves with animated movies, cartoons etc.

1.3 Some History

The term “computer graphics” was coined in 1960 by William Fetter to describe the new design methods that he was developing at Boeing. He created a series of widely reproduced images on a plotter exploring cockpit design using a 3D model of a human body.

Whirlwind: early graphics using Vector Scope (1951)

Spacewars: first computer graphics game (MIT 1961)