9 | *If they asked me, I could write a book;*
10 | *About the way you TALK, and LISTEN; And LOOK.*
12 -- with apologies to Richard Rodgers and Lorenz Hart.
14 Text adventures, otherwise known collectively as interactive fiction (IF),
15 were highly popular computer games during the 1980s. As technology evolved
16 they faded from the market, unable to compete with increasingly
17 sophisticated graphical games; however, IF was far from dead. The Internet
18 grew, and Usenet discussion forums offered a focal point for fans of the
19 genre. By developing IF programming tools and systems, organising contests
20 and writing tutorials and reviews, these enthusiasts have led a revival
21 responsible for many notable works, including some whose quality arguably
22 surpasses that of the best commercial titles of the 1980s.
24 Nowadays, IF is a hobby; almost everything that you need to begin writing
25 your own text adventures is available, for free, on the Internet. While
26 expert programmers may relish the considerable challenge of creating
27 interactive fiction using a generalised language such as BASIC or C,
28 specialist IF tools have largely solved the fundamental world-building
29 issues. The most common systems are Graham Nelson's Inform -- our subject
30 matter -- and Mike Roberts' TADS (Text Adventure Development System). New
31 hopefuls arrive each year, but few achieve widespread acceptance; the
32 majority of today's IF (and virtually all the works generally regarded as
33 interesting, innovative, sophisticated, etc.) have been created with
34 either one or the other. In our view, only TADS bears comparison with
35 Inform in popularity, in being able to handle simple and complex stories,
36 and in availability on PCs, Macs, hand-held devices and a wide variety of
37 other computers. But, since you're reading our guide, we'll assume that
38 you've already made a choice, and decided to give Inform a try.
40 We aim to provide a grounding in Inform basics. When you have learnt a
41 little about it, you'll be able to design simple games for your friends to
42 play and, as you become more accomplished, which you can share via the
43 Internet with enthusiasts worldwide. However, if you simply want to play
44 [#play]_ games written by others -- rather than write them yourself -- then
45 you don't need to learn Inform, and this guide isn't for you.
50 Because this is only an introduction to Inform, many features are treated
51 rather superficially, or ignored altogether. The definitive text is Graham
52 Nelson's Inform *Designer's Manual* (Fourth Edition, July 2001), commonly
53 known as the DM4; you cannot hope to use Inform successfully without having
54 this splendid book by your side. Our guide should be seen merely as a
55 supplement to the DM4, offering step-by-step descriptions of those aspects
56 of Inform which are most important on first acquaintance. In any matter
57 where we seem at odds with what Graham has written, you should assume that
58 he is right and that we are, well, confused.
60 As a tutorial, this guide is intended to be printed out and then read
61 sequentially; it isn't meant for online usage or designed as a reference
62 manual, though it does provide brief summaries of Inform's language and
63 library. Our approach is to teach you about Inform through the creation of
64 three games: all short, all playable to completion. "Heidi" is just about
65 as simple as an IF game can be, but still manages to introduce a range of
66 important concepts. "William Tell", a retelling of the famous folk tale,
67 is nearly as brief but roams more widely in its use of Inform's
68 capabilities. Finally "Captain Fate" presents a comic-book hero in urgent
69 need of a change. By the end of the guide, we'll have touched on less than
70 half of Inform's capabilities, but we hope we'll have mentioned most of the
71 things that matter when you're starting out to design your first Inform
74 One final point: Inform is a powerful system, often offering several
75 different ways of tackling a particular design requirement. We've tried to
76 present things as simply and consistently as possible, but you shouldn't be
77 surprised to discover other approaches, maybe shorter, maybe more
78 efficient, than those shown here.
80 Presentation and style
81 ======================
83 Most of the guide's text appears in this typeface, except where we're using
84 words which are part of the Inform system (like ``print``, ``Include``,
85 ``VerbLib``) or are extracted from one of our games (like ``bird``,
86 ``nest``, ``top_of_tree``). Terms in **bold type** are included in the
87 glossary -- Appendix G on page 273. We switch to italic type for a
88 placeholder: for example you should read the Inform statement:
94 as meaning "display on the player's screen the arbitrary character or
95 characters which are represented here by the placeholder *string*".
96 Examples might include::
99 print "Fourscore and seven years ago our fathers brought forth on
100 this continent a new nation, [...] and that government of
101 the people, by the people, for the people shall not perish
104 We place the "TYPE" symbol alongside game fragments which you can type in
105 as a part of our working examples. This differentiates them from other
106 code snippets whose only purpose is to illustrate some particular feature.
110 The "TYPE" symbol doesn't really work here. Think of a better way to
111 indicate typed-in fragments.
113 Useful Internet resources
114 =========================
116 One of our basic assumptions -- along with your burning desire to learn
117 Inform and your ability to work comfortably with the files and folders on
118 your computer -- is that you have access to the Internet. This is pretty
119 well essential, since almost everything you need is available only via this
120 medium. In particular, you'll find much helpful material at these
123 * http://www.inform-fiction.org/
125 The Inform home page, maintained by Graham Nelson and a small team of
126 helpers. Most important, this is where you can find the *Inform
127 Designer's Manual* in PDF format.
129 * http://mirror.ifarchive.org/
131 The IF Archive (or actually a high-speed mirror copy of it), from which
132 you can download almost anything that's free and in the public domain.
133 For a clickable map of Inform-related parts of the Archive, see
134 http://www.firthworks.com/roger/informfaq/hh.html.
138 Prior to August 2001, the IF Archive was located elsewhere, at
139 ftp://ftp.gmd.de/if-archive/, and references to that location can
140 still occasionally be found. *Do not use* the old location: any
141 information still available from there is likely to be out-of-date.
143 * http://www.firthworks.com/roger/
145 Roger Firth's Inform pages, including the Informary (what's new in
146 Inform?), and the Inform Frequently Asked Questions (FAQ) pages.
148 * http://www.plover.net/~textfire/raiffaq/
150 A more general list of FAQs about IF authorship, covering both Inform
151 and the other main systems.
153 * news:rec.arts.int-fiction
155 The Usenet newsgroup for authors of IF, commonly known by the
156 abbreviation RAIF. Here you'll find discussion on IF technology,
157 criticism and game design issues, and fast, friendly and knowledgeable
158 assistance with your own "how do I..." questions (but please, look in
161 * news:rec.games.int-fiction
163 The complementary newsgroup for IF *players*, often known as RGIF.
167 Update these links appropriately. The newsgroups in particular are
168 mostly unused these days.
173 Becoming sufficiently conversant with Inform to be able to share it with
174 others is not something done quickly or in isolation. In getting to where
175 we are today, we have been assisted at many times and in many ways by the
176 notably supportive and good-natured people, far too numerous to list by
177 name, who make ``rec.arts.int-fiction`` such an invaluable IF resource. We
178 are grateful to you all.
180 In creating this guide, we have received specific help from a number of
181 people. First and foremost we must mention Graham Nelson, who kindly wrote
182 the Foreword, and delighted us with long and detailed lists of helpful
183 comments and suggestions on two of our drafts; also Dennis G. Jerz, who
184 patiently and skilfully edited the text, making innumerable improvements to
185 our often wayward and inconsistent prose. David Cornelson supervised the
186 Second Edition's transformation into professionally printed respectability.
187 Further assistance came from Barney Firth, Christine Firth, Harry Firth,
188 Megan Firth, Jim Fisher, Rosemary Frezza, Phil Graham, Graham Holden, Paul
189 Johnson, Yoon Ha Lee, Brian Pylant, Jo Quinn, Milos Radovanovic, Muffy
190 St. Bernard, Gunther Schmidl, Emily Short, Curt Siffert, A. Sloe, Pavel
191 Soukenik, Elise Stone, Brent VanFossen and R. Cliff Young. Thank you: it
192 is impossible to overstate the value of this freely given support and
195 The drop capitals, and their associated poem, are from "A Picture
196 Alphabet", digitised from a collection of public domain woodcuts, circa
197 1834, by Steven J. Lundeen of emerald city fontwerks.
201 Reference to the drop-caps should only apply to those places they're
202 used (just the PDF?).
204 All credit to the generosity of http://briefcase.yahoo.com/ for making
205 international file-sharing such a breeze.
207 Finally, of course, we owe an enormous debt of gratitude to Graham Nelson
208 for devising it all, thereby giving us the opportunity -- first
209 independently and later in enjoyable collaboration -- of using, and
210 eventually of presenting, the Inform text adventure development system.
213 | *Wallingford, England*
220 .. rubric:: Footnotes
223 If you feel confused about IF in general or about this distinction
224 between writing and playing in particular, try glancing ahead at "Just
225 what is interactive fiction?" on page 13 and at "How to play an IF game"
226 on page 209; also, you may find the Ifaq at
227 http://www.plover.net/~textfire/raiffaq/ifaq/ helpful.