Table Of ContentAn Introduction to Object-Oriented Programming in c++
With Applications in Computer Graphics
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Graham M. Seed
An Introduction to
Object-Oriented
c++
Programming in
With Applications in Computer Graphics
Springer
Graham M. Seed, BEng, MPhil, PhD
Department of Mechanical & Chemical Engineering
Heriot Watt University, Edinburgh EH 14 4AS, UK
ISBN-13: 978-3-540-76042-9 e-ISBN-13: 978-1-4471-3378-0
DOl: 10.1007/978-1-4471-3378-0
British Library Cataloguing in Publication Data
Seed, Graham Mark
An introduction to object -oriented programming in C++ : with applications in computer graphics
I.C++ (Computer program language) 2.0bject-oriented programming (Computer Science)
1.Title
005.1'33
Library of Congress Cataloging-in-Publication Data
Seed, Graham M" 1965-
An introduction to object-oriented programming in C++ : with applications in computer graphics 1
Graham M, Seed.
p. cm.
Includes bibliographical references and index.
1. Object-oriented programming (Computer science) 2. C++ (Computer program language) 3.
Computer graphics. 1. Title.
QA76,64,S375 1996
006.6'6--dc20 96-21786
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© Springer-Verlag London Limited 1996
Softcover reprint of the hardcover 1s t edition 1996
The use of registered names, trademarks etc. in this publication does not imply, even in the absence of a
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The publisher makes no representation, express or implied, with regard to the accuracy of the information
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Typesetting: Ian Kingston Editorial Services, Nottingham
Printed and bound by Bell & Bain Ltd, Glasgow, UK
34/3830-543210 Printed on acid-free paper
To the memory of
Tom Bannister (1909-1992)
what a guy!
Preface
Why Another Book on c++ and why Programming and Graphics?
Anyone who has browsed through the 'Computing' section of a bookshop (assuming
it has one) will not need much convincing that there are a lot of C++ books out there.
So why add yet another to the shelf!
This book attempts to introduce you to the C++ language via computer graphics because
the object-oriented programming features of C++ naturally lend themselves to graphics.
Thus, this book is based around a central theme: computer graphics and the development
of 'real' object-oriented tools for graphical modelling. This approach is adopted (as opposed
to learning by small, unrelated, often hypothetical, examples) because I didn't want to
introduce C++ as a collection oflanguage features. While introducing the syntax and features
of C++, it is just as important to demonstrate simultaneously the reason for such features
and when to apply them -in otherwords,language and design are given equal priority. Also,
a key objective in writing this book is to present you with a comprehensive introductory text
on programming in the C++ language.
The first part of the book introduces the fundamentals of C++ programming. After
the foundations have been laid, the object -oriented programming features of C++ are
introduced via the development of classes such as Po in t and Line. These primitives
are then put to good use in developing powerful two-and three-dimensional graphics
classes such as Circle, Sphere, Triangle, Quadrilateral, Polygon and
Tetrahedra. Along the way, tool classes are also developed, such as Vector,
Vector3D,Ma trix,Cornplex,String,LinkedList,ReadFile and Wri te
File,World,DIBitrnap and many more.
What you Need to Know
No previous programming experience in C or C++ is required for this book. If you
are considering learning C before C++, then my advice is: don't. When I first started
to learn C++ I asked myself the exact same question and unfortunately made the
wrong decision and developed a good understanding of C before attempting to learn
C++. I wouldn't say that this proved to be a complete waste of time, but it is certainly
not necessary to learn C in order to learn C++.
As a C++ programmer you will develop programs and think about program design
in a completely different manner than the traditional procedural techniques in C. C++
offers a programmer object-oriented features such as encapsulation, abstraction,
inheritance and multiple inheritance, and polymorphism through the use of classes
and objects, member functions, operator overloading, virtual functions, templates,
exception handling, run-time type information and so on. In addition, C++ offers a
lot more. C++ provides many new features (for instance const, new and delete),
stronger type checking and minor, but nevertheless important, modifications to C.
vii
viii Preface
If you do know another procedural language, such as Fortran, Basic, Pascal or C,
then great. Some skills that you have learned with such languages will undoubtedly
prove useful (such as the meaning of variables, conditions and loops), whereas other
skills will appear to conflict with the c++ way of programming.
This book does assume that you have had some contact with computers before and
are familiar with Microsoft's DOS and Windows operating systems.
Hardware and Software Requirements
It is assumed that readers of this book have access to a computer and a compiler, such
as Borland C++,Microsoft Visual c++ or Symantec c++ for a Windows environment.
It is difficult to specify general minimum hardware and software requirements that
cover all compilers, but as an example, Borland c++ version 5.0 for Windows requires
Windows 95 or Windows NT, a hard disk with 175 Mbyte free disk space for a full
installation, at least 16 Mbyte RAM, a 3.5"/1.44 Mbyte floppy drive or CD-ROM and
a Windows-compatible mouse. An Intel 486 or higher processor is recommended.
Obtaining the Program Files
All of the source code, including solutions to chapter exercises, presented throughout
the book is available by an Internet ftp connection following the procedure:
ftp host name: ftp.springer.co.uk
login name: ftp
password: <your e-mail address>
ftp directory: /pub/springer/Books/3540760423
get: cpp-prog.zip
The program fIles have been compressed in to a single PKZIP fIle CPP _PROG.ZIP. To
preserve the chapter directory structure of the fIles use the -d option when unzipping
the fIles. For instance:
c:\cpp-prog>pkunzip cpp-prog.zip -d
Alternatively, the program fIles can be obtained via the following URL:
ftp://ftp.springer.co.uk/pub/springer/Books/3540760423
All of the programs have been tested with the Borland C++ and Microsoft Visual C++
compilers.
Preparation of the Book
The text of this book was written with the aid of Microsoft's Word for Windows
version 6.0. The C++ program code was written with the Borland Integrated Devel
opment Environment (IDE) editor. The program code was transferred from IDE to
Preface ix
Word using Copy and Paste. Tables and figures were completed using Word and
CorelDRAW version 5.0.
All program code developed for the book was developed exclusively on a desktop
PC consisting of an Intel Pentium 90 MHz CPU, 16 Mbyte RAM, 1 Mbyte video
memory and 1 Gbyte hard disk space.
How this Book !s Organised
It would be great to dive straight into the object-oriented programming (OOP)
features of c++. Unfortunately, this is simply not possible for an introductory text.
Therefore, the initial chapters lay the foundations of the c++ language by examining
the 'traditional' procedural C features of c++.
If you already have experience of another programming language, particularly C,
it may be tempting to skip the first few chapters and jump straight into the object
oriented features of c++. If you choose to do this then be careful. c++ has many
differences from and additions to C, some of which you may miss if you jump for OOP.
The object-oriented features really begin in Chapters 8 and 9, when structures and
classes are introduced.
The book begins by presenting a general overview of the C++ programming
language and object-oriented programming and what is meant by an object. We take
a look at the history of C++, its relationship to C and what makes C++ an object-ori
ented programming language. Chapter 2 briefly discusses your programming envi
ronment and what support to expect from a C++ compiler.
Chapter 3 introduces several key elements of program construction in C++ via the
simplest of programs. Each line of a simple C++ program is introduced in detail to
help the reader who is learning C++ for the first time feel comfortable with the basics
of program construction. The first elements of a C++ program discussed are user
comments, preprocessor directives, the use of header files, a function definition,
program statements, strings, the cou t standard output stream object, the endl
manipulator and the « insertion operator. The importance of developing a consis
tent programming style is stressed and several different popular styles are presented.
The fundamental data types of the C++ language, and their corresponding data
type modifiers, are introduced in Chapter 4. The notion of a constant or variable
identifier is demonstrated with the aid of numerous examples for each fundamental
data type, and the distinction between an identifier declaration and definition is
noted. Once data types have been introduced, statements, operators, expressions, type
conversions and casting are covered. Chapter 4 concludes by discussing storage class
specifiers and declaring assembly language program code directly within a C++
program.
Chapter 5 examines the process of making decisions and performing repetition in
C++. Decisions are implemented using either if-else or switch statements,
whereas repetition is performed using a for, while or do-while-loop. In addi
tion, C++ supports keywords such as break and default for if-else and
swi tch statements and the keywords break and continue for loops which allow
a programmer to interrupt program flow. Both decision-making and repetition
require the use of the-relational and logical operators, and Chapter 5 examines these
operators and the bitwise and shift operators in detail.
The function is the basic tool of the majority of programming languages for
modularising a large complex program. Chapter 6 discusses the C++ function: its
x Preface
construction, definition, scope and application. Chapter 6 also discusses the powerful
technique of function overloading, which C++ supports, and inline functions. The
chapter concludes with an application of functions to the popular geometric problem
of the intersection of two straight lines. Arrays are covered in Chapter 7. The chapter
discusses what an array is, how the elements of an array are indexed, the dimension
of an array and typical applications of arrays.
Chapter 8 presents structures, unions and enumerations for the creation of user
defined data types and typedefs for user-defined synonyms of data types. The
struct statement allows a programmer to create a new data type which is a
collection of similar or different data types. A union data type is similar to struct
except that a union can hold only one of its data members at any given time. The
user-defined enum data type is a collection of named data members which have
equivalent integer values. A typedef is a synonym for an existing data type.
The class is the key object-oriented programming feature of the c++ language,
and Chapter 9 covers the class in detail via a class called Point. Similar to
struct, the class allows a programmer to create new data types by encapsulating
data members, but the class also allows a programmer to encapsulate member
functions which operate on a class's data members. Operators and overloading
operators for user-defined data types are examined in Chapter 10. Overloading
operators for a user-defined class can significantly enhance the level of abstraction
of the class.
Friend functions and classes are introduced in Chapter 11. Basically, a friend
function or class has access to the private data members of an object of a given
class, although the friend is not a member of that class.
Chapter 12 comprehensively examines the tricky subject of pointers. The dynamic
memory allocation and de allocation operators new and delete and the this
pointer are examined. Useful Vector and Matrix classes are developed which
make good use of pointer manipulation and the new and delete operators, and
help apply many of the topics covered in previous chapters.
Generic functions and parametrised data types are introduced in Chapter 13
through the template language-based feature. The exact type of object(s) that a
function or c las s operates on is left unspecified in the function definition or class
declaration until a function is called or an object is defined. The C++
try-catch-throw termination mechanism for handling runtime errors is pre
sented in Chapter 14 and demonstrated for various classes.
The topic of class inheritance is covered in Chapter 15, which allows a derived
class to inherit the features of one or more other base classes. Several properties of
inheritance are discussed with reference to a Shape class hierarchy, including
polymorphic classes which contain one or more virtual functions. Chapter 16
examines the run-time type information mechanism, which allows a programmer to
obtain the type of an object at run-time, and the related topic of casting.
Both C and c++ streams are discussed in Chapter 17. Standard input and output
and fIle streams are covered and an overview is given of the C function-based and
C++ class-based stream libraries. Chapter 18 discusses the preprocessor, although
it is not strictly part of the C++ language.
Chapter 19 discusses namespaces, one of the newest major features to be added to
the C++ language. Namespaces are a language-based solution to the problem of name
clashes resulting from C++'s single name space for a translational unit.
The final chapter concludes the book with an application of the C++ programming
language to the development of a simple object-oriented ray-tracing program. The
