General Introduction

General Introduction

TADS 3 TOUR GUIDE

FOR TADS 3.1

The adv3 library that comes with the TADS 3 Interactive Fiction authoring system is extensive and powerful. It can also seem rather overpowering to new users of TADS 3, because there is so much to learn, and one hardly knows where to start looking for what one needs.

Enter the TADS 3 Tour Guide. Its aim is to give a guided tour of some of the main features of the TADS 3 library. We shall not be exploring every nook and cranny (at this stage it would probably be more confusing than helpful to do so). Nor shall we be able to wander down every side street and alley, though we may poke our noses into a few. What we shall aim to do is to walk round most of the main streets so that their basic layout and interconnections will hopefully start to become clear.

This Tour Guide is not intended as the first port of call in learning TADS 3. If you are a complete beginner I strongly recommend you start with my introductory Getting Started in TADS 3 : A Beginner's Guide, which you can download from http://www.tads.org (or which you may already have with your TADS 3 distribution). Although there will be some overlap with material covered there, the Tour Guide assumes basic familiarity with programming in the TADS 3 language and the definition of simple TADS 3 objects. For this Guide is not a TADS 3 manual, or a substitute for one. Neither is it an introduction to writing games in TADS 3, or an exhaustive description of every Class, property and method in the TADS 3 library. Finally, it is not a complete guide to the TADS language, many features of which are already well documented in the System Manual that come with the TADS 3 distribution, or which can be downloaded from http://www.tads.org.

What this Tour Guide is is a kind of Guided Tour to the TADS 3 library, that tries to take in as many as possible of the classes, properties and methods that are likely to be useful to most game authors. The assumption is that what you will find useful is not so much a load of abstract explanation, but rather a series of concrete examples. This Tour Guide therefore takes you through developing a sample game, introducing each Class in turn with one or two examples of its use. Later sections re-use classes and properties introduced before, and sometimes suggest further sophistications.

This Guide may thus be used either as a tutorial or as a reference (or both). As a tutorial it may be worked through from start to finish, developing the game step-by-step until all the main features of the library have been introduced and exemplified; you may like to use it as a follow-on tutorial from Getting Started in TADS 3. But it may also be used as a reference to the use of various library classes. For the latter purpose the Windows help file version of this Guide is likely to prove most useful; for the former you may prefer the PDF version. Note, however, that the Tour Guide will probably be more useful as a reference once you have worked through it as a tutorial, since in the very nature of its treatment of developing a game, its later sections presuppose objects and concepts mentioned in earlier sections, and many techniques have to be introduced in passing. Note also that a complete reference to the library is provided by the TADS 3 Library Reference Manual.

Of necessity there must be some compromise between the need to develop the sample game in a reasonably logical sequence and the desirability of presenting the various library classes in a reasonably logical sequence. For this reason we start by looking at Rooms and Connectors, since laying out some kind of map is necessary before anything much else can happen in a game. We then go through the other Classes representing concrete game objects, before going on to look at the creation of NPCs and the use of more abstract classes for conversations, scoring, hints and the like.

IMPORTANT NOTE - This Guide is intended for use with TADS 3.1. Although changes from the immediately preceding versions of TADS 3 (especially TADS 3.0.12 and later) are relatively minor prior, successive library updates have substantial changes; if you are using a significantly older version of TADS 3 a great deal in this guide may not work. Please therefore:

·	Update to TADS 3.1 before attempting to work through this Guide. See http://www.tads.org/t3dl.htm.

·	If, for some reason, you are unable to update to TADS 3.1, please be aware that any problems you encounter may be due to incompatibilities between versions of the library rather than bugs in the sample code.

Finally, I hope this Tour Guide will prove helpful, and even enjoyable to use. I always welcome feedback and suggestions, not least those that point out genuine errors, typos or bugs. I can be contacted by email on eric dot eve at hmc dot ox dot ac dot uk.

Eric Eve
08-May-11