Fundamentals of Computer Graphics, 3rd Edition

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Introduction

The term computer graphics describes any use of computers to create and ma-

nipulate images. This book introduces the algorithmic and mathematical tools

that can be used to create all kinds of images—realistic visual effects, informative

technical illustrations, or beautiful computer animations. Graphics can be two- or

three-dimensional; images can be completely synthetic or can be produced by ma-

nipulating photographs. This book is about the fundamental algorithms and math-

ematics, especially those used to produce synthetic images of three-dimensional

objects and scenes.

Actually doing computer graphics inevitably requires knowing about spe-

cific hardware, file formats, and usually a graphics API (see Section 1.3) or two.

Computer graphics is a rapidly evolving field, so the specifics of that knowledge

API: application program in-

terface.

are a moving target. Therefore, in this book we do our best to avoid depending

on any specific hardware or API. Readers are encouraged to supplement the text

with relevant documentation for their software and hardware environment. For-

tunately, the culture of computer graphics has enough standard terminology and

concepts that the discussion in this book should map nicely to most environments.

This chapter defines some basic terminology, and provides some historical

background as well as information sources related to computer graphics.

1.1 Graphics Areas

Imposing categories on any field is dangerous, but most graphics practitioners

would agree on the following major areas of computer graphics:

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2 1. Introduction

• Modeling deals with the mathematical specification of shape and appear-

ance properties in a way that can be stored on the computer. For example,

a coffee mug might be described as a set of ordered 3D points along with

some interpolation rule to connect the points and a reflection model that

describes how light interacts with the mug.

• Rendering is a term inherited from art and deals with the creation of

shaded images from 3D computer models.

• Animation is a technique to create an illusion of motion through sequences

of images. Animation uses modeling and rendering but adds the key issue

of movement over time, which is not usually dealt with in basic modeling

and rendering.

There are many other areas that involve computer graphics, and whether they are

core graphics areas is a matter of opinion. These will all be at least touched on in

the text. Such related areas include the following:

• User interaction deals with the interface between input devices such as

mice and tablets, the application, feedback to the user in imagery, and

other sensory feedback. Historically, this area is associated with graph-

ics largely because graphics researchers had some of the earliest access to

the input/output devices that are now ubiquitous.

• Virtual reality attempts to immerse the user into a 3D virtual world. This

typically requires at least stereo graphics and response to head motion.

For true virtual reality, sound and force feedback should be provided as

well. Because this area requires advanced 3D graphics and advanced dis-

play technology, it is often closely associated with graphics.

• Visualization attempts to give users insight into complex information via

visual display. Often there are graphic issues to be addressed in a visualiza-

tion problem.

• Image processing deals with the manipulation of 2D images and is used in

both the fields of graphics and vision.

• 3D scanning uses range-finding technology to create measured 3D models.

Such models are useful for creating rich visual imagery, and the processing

of such models often requires graphics algorithms.

• Computational photography is the use of computer graphics, computer

vision, and image processing methods to enable new ways of photographi-

cally capturing objects, scenes, and environments.