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Opening the black box — practical computer graphics
Opening the black box A practical introduction to computer graphics, Ian 0 Angell, Macmillan (I 983) L5.95 To many practising chemists, computer graphics is just one more black box. Those who wish to prise the lid off will undoubtedly be attracted by the title of Dr Angell’s book. Thumbing through its pages, however, the casual reader might at first be disappointed, since the text is chiefly concerned with the use of coordinate geometry in Fortran programs for generating line drawings. While it is true that such drawings are at the heart of computer graphics, the term has nowadays taken on a much richer connotation. What we expect to find in a book with this title is not only a description of the mathematical apparatus but, in addition, some explanation of how the hardware works, how a newcomer can make a sensible choice between the various types of display system and how he can make the best use of the wide range of interactive devices currently available. These aspects are scarcely mentioned. Nevertheless, there is much good material between its covers. The author nicely captures the essence of the subject on the first page, where he comments that any problem in computer graphics reduces to specifying points in 2D space and joining them in pairs with straight lines, or filling in the areas bounded by such lines - the real problem
88
practical computer graphics
being how to specify the points. From then on, the development is systematic, as the author works step by step through the relevant coordinate geometry and transformations of steadily increasing complexity. His style is clear and readable, and anyone whose job it is to write graphics software will find that all the nuts and bolts are there algorithms for translation, scaling, rotation, perspective and and removal of stereo viewing, hidden lines. Advice on animation is also included. The approach is mathematical throughout, many of the illustrabeing abstract geometritions cal patterns, vaguely reminiscent of Islamic art. There is not a molecule in sight, which is a salutary reminder to chemists that the major impact of computer graphics to date has been in the engineering and entertainment industries, and not in science. The mathematical bias comes out most strongly in the discussion of the co-ordinate geometry of 3D space which is carried through without a single illustration. The author explains that diagrams were left out in order to establish confidence in the mathematical representation of points, lines, planes and surfaces. It is surely ironical that in a book with this title, diagrams should be deliberately suppressed at the point where they have most to offer. In spite of the mathematics, this is essentially a practical book. It is the
author’s
conviction
The only branch completely number of
that
way to understand any science computer of is to study and write a large programs.
Clearly then, this is not a book to be read in an armchair; the reader needs to be seated at his terminal, with his plotter switched on. Indeed, with a subroutine on almost every page the text could easily become a cookbook to which programmers will turn for a quick solution to their problems something which the author would no doubt abhor. Sixth form students with an interest in CAD and a working knowledge of Fortran will find it meets most of their needs, while their tutors should find plenty of stimulating material among the list of 17 suggested projects. It is a pity that there are no references to other texts, or to the original literature. the book invites Inevitably, comparison with the classics by Newman and Sproull, and by Foley and Van Dam. The contrast between this slim paperback on the one hand and its plush US rivals on the other is almost symbolic of the gulf between the cultures of the Old World and the New - or at least, between their two standards of living. It will be interesting to see whether the next generation of graphics programmers have fared better on Lancashire hotpot or on apple pie and ice cream. K J Heritage
Journal
of Molecular
Graphics
88
practical computer graphics
being how to specify the points. From then on, the development is systematic, as the author works step by step through the relevant coordinate geometry and transformations of steadily increasing complexity. His style is clear and readable, and anyone whose job it is to write graphics software will find that all the nuts and bolts are there algorithms for translation, scaling, rotation, perspective and and removal of stereo viewing, hidden lines. Advice on animation is also included. The approach is mathematical throughout, many of the illustrabeing abstract geometritions cal patterns, vaguely reminiscent of Islamic art. There is not a molecule in sight, which is a salutary reminder to chemists that the major impact of computer graphics to date has been in the engineering and entertainment industries, and not in science. The mathematical bias comes out most strongly in the discussion of the co-ordinate geometry of 3D space which is carried through without a single illustration. The author explains that diagrams were left out in order to establish confidence in the mathematical representation of points, lines, planes and surfaces. It is surely ironical that in a book with this title, diagrams should be deliberately suppressed at the point where they have most to offer. In spite of the mathematics, this is essentially a practical book. It is the
author’s
conviction
The only branch completely number of
that
way to understand any science computer of is to study and write a large programs.
Clearly then, this is not a book to be read in an armchair; the reader needs to be seated at his terminal, with his plotter switched on. Indeed, with a subroutine on almost every page the text could easily become a cookbook to which programmers will turn for a quick solution to their problems something which the author would no doubt abhor. Sixth form students with an interest in CAD and a working knowledge of Fortran will find it meets most of their needs, while their tutors should find plenty of stimulating material among the list of 17 suggested projects. It is a pity that there are no references to other texts, or to the original literature. the book invites Inevitably, comparison with the classics by Newman and Sproull, and by Foley and Van Dam. The contrast between this slim paperback on the one hand and its plush US rivals on the other is almost symbolic of the gulf between the cultures of the Old World and the New - or at least, between their two standards of living. It will be interesting to see whether the next generation of graphics programmers have fared better on Lancashire hotpot or on apple pie and ice cream. K J Heritage
Journal
of Molecular
Graphics