Cream of the Crop 11/Cream of the Crop 11-1.iso/games/dcgames4.zip/DCSCRIPT.DOC

Text File | 1995-10-02 | 76KB | 2,696 lines

Introduction     1

Preface     1

Document Organization     1

Conventions     2

Getting Help     2

Basic Information     3

What is a script?     3

What is a script used for?     3

Character scripts     3

Object scripts     4

World script.     5

Control script     5

Magic Spells     5

Game Initialization Script     6

Dead and Resurrection     6

Basic Script Elements     7

Keywords     7

Keywords Table     8

Comments     8

Numbers     9

Tokens     9

Variables     10

Generic Variables (Local and Global)     10

String Variables     10

World Variables and Attributes     11

Object Variables and Attributes     11

Character Variables and Attributes     13

Group Variables and Attributes     14

Types of Scripts     15

Introduction Script     15

Character Script     16

Object Script     17

World Script     18

Control Script     18

Resurrection Script     18

Writing Scripts     19

Script Files     19

Expressions and Assignments     20

Function Table     21

Statements     22

Conditional Statements     22

Flow Control Statements     23

Flow control using if     23

Flow control using on-goto     23

Loop Control Statements     24

The while statement     24

The for statement     24

The foreach statement     24

Object Manipulation Statements     25

Move and Copy     25

Drop     25

Output Statements     25

Write and Writeln     25

Display     26

Input Statements     26

Getstr and Getnum     26

Select     26

Going Places     26

Animation     27

Entering Doors     27

Teleportation     27

Advanced Topics     27

Entry Points     27

Calling A DOS program     28

Creating New Types and Classes     29

New Character Types     29

New Character Classes     29

New Object Types     30

New Object Classes     30

New Object Modifiers     31

New World Types     32

Shareware Opportunities     33

Extending the magic system     33

MS-DOS based extensions     33

Writing a whole new system     34



















D C  -  G A M E S





Version 4.0



SCRIPT LANGUAGE USER'S GUIDE



















August 1995





(c) DC Software, 1989-1995

7908 Kettlewood Court

Plano TX 75025

[phone]Introduction

Preface

One of the goals of the DCGAMES adventure and role-playing game
building system is to provide an environment in which you can
create adventure games without having to know anything about
computer programming, and without having to maintain a zillion
lists of cryptic numbers.  If you want to draw a river, you just
do it.  If you want to create a dragon, just grab the right
picture and do it.  The idea is to have a large enough set of
objects, characters, monsters and landscaping to allow you to
concentrate on the story.

While this works fine most of the time, it is almost inevitable
that there will be a few things you need to do that I didn't
think of, or which need to work slightly different.  You may
need a new type of character or object, or some new magic
spells.  Maybe the wizards are too wimpy or elves and dwarfs
should not exist in your adventure.

Most of the features in the DCGAMES system are handled by
scripts.  The script language is a simple yet powerful language
that the game driver understands, and which control the behavior
of most parts of the game system.

The scripts are created using a standard text editor, and can be
as simple or complex as you need them to be.  While you can
write a complete game without writing a single line of script, a
small effort on your part to learn how to write script will
result in significantly better games, since you can fine-tune
your creation to work exactly the way you want it to work.

Document Organization

This manual is organized in several sections.  The first one is
an introduction to the elements of the DCGAMES system.  It
explains each of the building blocks used to create an
adventure, and how (and why) you would want to customize them.
Everyone should read this section!

The second section is a Reference Manual, which is a list of the
features of the script language in a logical order.  You will
need a printed copy of that section of the manual when you are
actually writing a script.

Conventions

In this document, the following conventions are used:

UPPER-CASE-WORDS

represent tokens that have a specific value and are typed
exactly as shown.

italic-words

are used when a new concept is being introduced, and the world
in italics is the name of that concept.  They are also used to
indicate that you should be replace the word with an appropriate
name or value.

bold-words

represent names or values that should be typed exactly as shown.

text1 | text2

items separated by a vertical bar (|) mean you get to choose one
of them.

[text1 ]

items enclosed in square brackets are optional.  If multiple
items are listed, separated by a vertical bar, then you may
choose one of them or none.

{ text1 | text2 }

items enclosed in curly braces are NOT optional.  You must
select one of the items listed.

...

three dots (ellipsis) indicate that the previous item can be
repeated multiple times.  If there is a limit to the number of
times an item can be repeated, it will be indicated in a note
near the area where the ellipsis were used.

Getting Help

Registered users of DCGAMES get free telephone assistance
evenings and weekends.  This assistance may range from
explaining how a certain feature works to guidance in how to add
a new feature.  I might even write some specialized scripts for
you (within reason).

Non-registered users are welcome to call also.  I will try to
answer questions over the phone, but please keep your questions
simple and organized.  If you feel you can't afford to pay for
the game, I've been known to accept a smaller amount or even
waive the fee in exchange for some serious feed back or some
outstanding artwork or sound recordings that I may incorporate
into the shareware product.Basic Information

Who should read this guide?

You need to read this guide if you are already familiar with the
DCGAMES system and are ready to extend or modify the system to
suit a particular game's requierments.

It is very important that you be familiar with the world builder
program (DCWORLD) before you try to modify the scripts.

What is a script?

A script is a text file, created using a simple text editor (If
you use a word processor, be sure to store the file in 'ASCII'
or 'PLAIN TEXT' format).

The script file contains the instructions that tell the game
driver (DCPLAY program) how to handle most aspects of the game.
The system includes a large number of predefined scripts to
handle objects, characters, worlds, etc.  You can modify these
scripts to meet your game's individual requirements, and you can
write whole new scripts to extend the number of options you have.

The DCGAMES system includes a large set of predefined scripts
which are used to handle your game.  While these scripts are
complete, you may want to modify them or write new scripts to
handle your specific needs. The type of script you write depends
on the aspect of the game that you want to control.

The script language was designed to be easy to learn and use.
The documentation was written specifically for people that have
no prior exposure to programming, and the predefined scripts
have extensive annotations to help you understand them and learn
from them.

A good thing to remember is that you cannot cause any damage
through experimentation.  The worst you can do is to make some
changes to a script that prevent it from operating properly.
All you have to do is retrieve a copy of the original script
(which you saved before you modified the script, right? right!)
or at worst, you can give me a call and I will help you fix it.
Don't be afraid to try!

What types of scripts are there?

Every aspect of the game is controled by scripts to a large
extent. These scripts call other scripts which in turn may call
other scripts themselves.

Control scripts

The CONTROL script is called every time you click with the mouse
or press a key on the keyboard.  This script decides what action
to take based on your input.  Thus, while the default control
script interprets the letter A to mean 'attack' and a click in
the view area with the left mouse button to mean 'look-at', you
can modify the complete interface to do whatever you want.

The control script is also called every 'minute' of game play.
Using the world builder you can specify how time flows in your
game (# of moves per minute, # of minutes per hours, # of hours
per day, # of days per month, # of months per year, current
date, etc.).  The game driver then invokes the control script to
keep track of time and allow it to take time dependent actions.

Game Initialization Script

When the game first starts, the INITGAME script will be invoked.
 This script is used to present the game's story.  You can use
voice, music, graphics, text, animation, etc.

Within this script you also have the chance to create and
customize the player's character or even the whole party. The
default character stored in record 0 of the statistics file
(PLAYERS.DTA) will be used if you don't create one.

Dead and Resurrection

The RESURECT script is invoked whenever all members of the party
die. In this script you have the chance to load a saved game,
restart the game from the begining or even resurect the party
members.

The default resurection script will restore the party members a
limited number of times by comparing the number of times they
have been resurected with the current experience level. It then
transports the party to the place where the game started.

Remember that you can set the rules and do whatever you want.
Some games I've seen will reduce an individual's experience as a
penalty for resurection but leave them where they were. Others
will teleport the party to a different location for resurection.

Character scripts.

When the control script determines that you want to interact
with another character, it invokes the character's script to
handle the interaction.

Every character in your game has a character type that
determines it's behaviour. The list of character types is
defined in the DCCTOKEN.DAT file and the behaviour is handled by
a script with the same name as the character type.

DCGAMES includes a full set of character types with their
respective scripts:  Regular, Bartender, Beggar, Civilian,
Guard, Healer, Merchant, Prisoner, Teller and Trainer.

The behavior of these character types is described in detail in
the DCGAMES Player's Guide.  One of the best ways to become
quickly familiar with the script language is to compare the
description of the character type as documented in the Player's
Guide with the actual script that makes the character behave
that way.

To create your own character types, you add the name of the
character type to the list in DCCTOKEN.DAT and then create a
script with that name to handle it's behaviour. If a name is
longer than 8 characters, you use the first 8 characters for the
script name.

Note: individual characters can have their own individual script
to override some or all of the character's standard behaviour.
When a character has it's own script, the driver allows the
character's script to handle the behaviour and invokes the
default script for the character's type only if the individual
script does not handle a particular action.

Object scripts.

When the control script determines that you want to use an
object in some way, it invokes the object's script to handle the
action.

If the action is on an object you are carrying, the CURRITEM
script is invoked.  If the action is on an object you are not
carrying, the OBJECT script is invoked.

These two scripts handle the standard behaviour for all of the
object types defined in DCCTOKEN.DAT.  You can add new types to
the list and modify these scripts to handle actions on the new
object types.

The default scritps handle Food, Weapon, Ammunition, Armor,
Shield, Amulet, Ring, Potion, Scroll, Staff, Chest, Keys, Gems,
Book, Gold Sack, Torch, Lantern, Rope, Hooks, Mirror, Sign,
Vehicle, Thing, Door and Fence objects.

You can also override an object's default behaviour by providing
a tailor-made script for that particular object. Any action
that is not handled by your script will be handed over to the
default script for handling.

You can alter the behavior of an object in several ways. You may
modify the OBJECT.SCR to alter the way existing objects types
work, or define new object types; You can also create a brand
new script file to control the behavior of a specific object.

World scripts.

When the player enters or exists a world, the world's script is
executed. The predefined script WORLDDEF.SCR is executed if you
don't provide one of your own. The world's script can deny
access to the world, or send the character to a different
destination within the same world or in any other world.

The file DCCTOKEN.DAT contains a list of world types (Outdoors,
City, Town, Dungeon, Hideout, House, Castle, Arena, Haunted and
End-Game) which you can modify at will.

The world script handles entry and exit from each world, but
other scripts are also involved.  For example, the CONTROL
script will generate random monsters only in OUTDOORS, DUNGEON
and HAUNTED worlds. It also handles walking of the 'edge' of the
world (if outdoors you wrap around to the other edge of the
world, but in cities and towns you 'leave' the world).

Magic Spells

When you invoke magic by using an object, the OBJECT and
CURRITEM scripts handle the action, but when a magic users
'casts' a spell, no object is involved, so a separate script is
used.  The CASTING script handles the casting of magic spells.

For more information on magic, see the Player's Guide and the
World Builder User's Guide.

Basic Script Elements

This section introduces the basic elements that form the script
language. Just like in English you use words to build sentences,
and those words are classified into verbs, adjectives, etc, so
does the script language use a basic set of elements to build
it's sentences.

The script language contains the following basic elements:
Keywords, Tokens, Constants,  Variables, Structures, Statements,
Functions, Procedures, Comments.  Let's look at each one in turn.

Keywords

A keyword is a word that has a special meaning in the script
language. You cannot change the spelling or meaning of the
keyword, because the game system has a specific meaning for it
and depends on that meaning.

A primary keyword is equivalent to a verb in the English
language.  It indicates the action taking place.  These keywords
form the basis of the script language. For example, if, goto,
write, etc.

A secondary keyword exists only to complement a primary keyword,
and has no meaning by  itself. For example, the if primary
keyword has four secondary keywords associated with itself,
namely: then, elsif, else and endif.

For example:

if player.name = "Henry" and fighting then

  write("Go Away");

endif;



In the above line, the if and write keywords are primary,while
then, and endif are secondary because they have a meaning only
in relation to the if keyword. (Note that and is also a
secondary keyword, but has nothing to do with if I didn't
highlight it).

A function keyword is used to examine or modify a system value.
This is a value that has a meaning to the game system, but you
can examine and sometimes modify it to change the way the system
behaves.

For example, if the keyword fighting in the previous example has
a TRUE value if the game system is currently in combat mode (a
fight is taking place), so the script displays the words 'Go
Away' if the current player's name is Henry and you are fighting.

Note that words such as player, npc, object, world,group,  etc.,
are called variables and their qualifiers (like player.name or
world.landscape) are called attributes. These are covered
elsewhere in this manual.

The section Writing Scripts in this manual introduces most of
the keywords using simple examples.  A detailed description of
each keyword can be found in the Script Language Reference Guide.

List of Primary, Secondary and Function Keywords1

Comments

A comment is a sequence of characters beginning with the
character '!'.  The exclamation point tells the script language
compiler that the text that follows is a comment and should be
ignored.  Comments are used to document your scripts so they are
easier to understand.

For example:

! This is a comment

   ! This is also a comment! All of it..

!!! This is another comment.



Note that all text following first ! is part of the comment,
including any other ! character.

Numbers

Numbers are very important in DCGAMES.

They are used extensively to identify the attributes of objects
and characters. As a rule, numbers can be values between
-2147483647 and 2147483647.  While this is true for constants,
when using numbers, you will usually have to restrict them to be
within the range of values allowed for the purpose you are using
the number for.  For example, a ring object has an attribute
called charges which holds the number of times the ring can be
used.  This attribute can have a value between 0 (no charges
left) and 255.  Trying to set the charges attribute to 500 will
result in a warning message, and assign the maximum allowed
value of 255. The range of values that an attribute can take are
documented along with each attribute in the section entitled
STRUCTURES further on in this chapter.

Tokens

When you write a script, you frequently need to examine and
modify the attributes of objects and characters, or to perform
different actions depending on the values of the same.  While
most of these attributes are numeric, you don't need to remember
what each number means.  Instead, tokens have been defined that
represent the numeric values.

In this document, tokens are shown in UPPER CASE.  Any name
shown in upper case letters can be considered to be a token.

For example.  The standard product includes a set of pre-defined
object types such as FOOD, WEAPON, ARMOR, etc.  The game uses a
number to represent the object's type (0, 1, 2, 3, etc), but it
would be difficult to remember that if you want to create a
WEAPON, you need to set the object's type to 1.  Thus, a token
(namely WEAPON) can be used.  A complete list of predefined
tokens, their values and their usage can be found in the
appendix.

If you modify or extend the set of pre-defined element types,
you will also add new tokens to the file DCCTOKEN.DAT, which
associates the token name with the actual value it is going to
represent.  Once the name has been added to the file, you no
longer have to remember what value you were using for your new
'type' or 'class' or whatever.

Variables

A variable is a name used to represent a value, just like a
token, but the difference is that the variable holds a value,
and the value can be modified.  For example, an object could
have a weight of 100, but you can change that value any time.

Variables are shown in bold letters in this document.  A
variable may have more than one value associated with it (for
example, an object has a name, a value, a weight, etc.).  The
values associated with the variable are called the attributes of
the variable.

The following paragraphs hold a complete list of all variables,
their names, attributes, values and a brief description of the
meaning of the associated value.

Generic Variables (Local and Global)

There are 2048 local variables, named L0 through L2047.  They
can hold values between -32768 and +32767.  They are called
local because they exist only during execution of the script.
Once the script has been executed, any value you placed in them
is lost.

Every time a script starts execution, it's local variables are
initialized to zero.  These variables are used mostly for
control purposes and to hold intermediate values.



There are 2048 global variables, named G0 through G2047.  These
variables can hold values between -32768 and +32767.  They are
called global because they exist for the entire duration of the
game.  If you set one of these variables to a certain value, it
will retain that value until you change it again.  These
variables are used to hold values that are important throughout
the life of the game.  For example, you might use one of these
variables to indicate that a certain action has taken place.
Other scripts could then check the value of the variable and
take different actions depending on whether the action has taken
place or not.



String Variables

There are 17 string variables, named S0 through S16.  They are
different from other variables in that they hold TEXT instead of
numbers.  They are also different in that they are used for some
specific purposes, and so, are not "generic".

Variable S0 can contain up to 255 characters. While you can use
it for any purpose, it is also used to store any text that the
player types during conversations, as well as other values.  The
getstr() script function asks the user to type something, and
stores that value in this variable (among other things).

Variables S1 through S16 can contain up to 64 characters.  These
variables hold the 16 lines of text associated with the current
object or character.  The loadtext() script function will load a
given text record and place each of the lines in the
corresponding variable.

Character Variables and Attributes



A character in the adventure can be a simple 'extra', with no
other function than to  flesh out a story, or it can be an
integral part of it.  Every character is controlled by a script,
and the system includes a large number of predefined scripts to
handle different types of characters.  Amongst the different
types of characters are: Regular, Bartender, Merchant, Civilian,
Quester, Beggar, etc.  Each of these character types has it's
own script,  and when you create a character, you will usually
select one of these scripts to handle it's behavior.  You may
extend the functionality of each character type by modifying the
scripts, or you can create brand new scripts to handle a brand
new type of character.  For those characters that are central to
the story, you may even want to create a special script that
handles their unique behavior.



When referring to characters, you may talk about the player or
the npc. In any interaction, the player is  a member of the
game player's party.  The npc is the member with which the
player is interacting.

Character Attributes     Description

name     Name of the character (15 characters max).

index*     For players, the order in the party. For npcs their
location in the list of npcs.

type     Character Type: (0-255). See tokens in DCCTOKEN.DAT
[Character Types]

class     Character Class (0-255). See tokens in DCCTOKEN.DAT
[Character Class]

block     Tile # from the DCPEOPLE.nnn graphics blocks file used
for this character

block2     Alternate Tile # used in some instances (under script
control only)

picture     Image file (0-999). If given, the file CPICTnnn.PCX
contains the picture.

voice     Voice file (0-999). If given, the file VOICEnnn.RSP
contains the voices.

x     Character's current horizontal location in the current world.

y     Character's current vertical locatioin in the current world.

count     For NPCs only, it's the # of npcs represented by the
individual NPC.

script     Optional SCRIPT for this character. Uses the character
type as default.

text     Optioinal text record (0-n).

load/mload     Current/Maximum load (how much weight can be
carried)

str/mstr     Current/Normal strength

aim/maim     Current/Normal aim

dex/mdex     Current/Normal dexterity

spd/mspd     Current/Normal speed

pwr/mpwr     Current/Normal magical power points

hp/mhp     Current/Normal Hit Points

iq/miq     Current/Normal intelligence

ac/mac     Current/Normal Armor Class

luk/mluk     Current/Normal Luck

chr/mchr     Current/Normal Charisma

exp     Current experience points

level     Current character level

poisoned     Character is poisoned

scared     Character is scared

paralyzed     Character is paralyzed

confused     Character is confused

invisible     Character is invisible

energy     Current energy level (From food.  See group.energy for
energy from sleep).

stats     Character statistics record.

v0 - v7     Extra variables to be used for any purpose you need.

weapon     Currently wielded weapon (if any)

armor     Currently worn armor (if any)

shield     Currently worn shield (if any)

ring     Currently worn ring (if any)

amulet     Currently worn amulet (if any)

staff     Currently wielded staff (if any)

bp     Currently selected backpack object (The backpack can hold
16)

body     Currently selected body object (if any, one of the
following 6 objects).



Object Variables and Attributes



An object is an item that can be manipulated in many different
ways during game play.  The object's TYPE and CLASS determine
what can be done with the object.

Most of the behavior of objects is controlled from the
predefined script OBJECT.  This script can handle objects of
type food, weapon, ammunition, shield, armor, ring, amulet,
scroll, staff, chest, vehicles, etc.

Object Variables     Description

player.weapon     The weapon wielded by the current player (if
any).

player.armor     The armor worn by the current player (if any).

player.shield     The shield being used by the current player (if
any).

player.ring     The ring being worn by the current player (if any).

player.amulet     The amulet being worn by the current player (if
any).

player.staff     The staff being used by the current player (if
any).

player.body     The last selected body item (represents one of
player.weapon, player.armor, player.shield, player.ring,
player.amulet or player.staff.

player.bp     The last selected backpack item for the current
player.  The backpack can hold up to 16 items, but only one of
them is selected at a time.

npc.weapon     The weapon wielded by the current npc (if any).

npc.armor     The armor worn by the current npc (if any).

npc.shield     The shield being used by the current npc (if any).

npc.ring     The ring being worn by the current npc (if any).

npc.amulet     The amulet being worn by the current npc (if any).

npc.staff     The staff being used by the current npc (if any).

npc.body     The last selected body item (represents one of
npc.weapon, npc.armor, npc.shield, npc.ring, npc.amulet or
npc.staff.

npc.bp     The last selected backpack item for the current npc.
The backpack can hold up to 16 items, but only one of them is
selected at a time.

group.vehicle     The vehicle the group is currently on (if any).

object     The object represented by this variable is not being
carried by anyone. It exists on it's own in the current world.

curritem     The object represented by this variable is being
carried by either the player or the npc character, either in the
backpack or being worn.  It is used when the exact location of
the object is not important.



Each of the objects listed above has the following attributes
associated with it.  Thus, you can type: npc.weapon.name,
player.bp.count, group.vehicle.type, curritem.class, etc.

Object Attributes     Description

name     Name of the object (15 characters max).

index*     Current position of the object in it's place (world,
backpack, etc.)

type     Object Type (0-255). See DCCTOKEN.DAT section [OBJECT
TYPES]

class     Object Class (0-255). See DCCTOKEN.DAT sections [OBJECT
CLASS: x, y]

block     Tile # from file DCOBJECT.mde used to display the object.

picture     Image file # (000-999). If given, file OPICTnnn.PCX
contains the picture.

voice     Vioce file # (000-999). Objects can have a sound file
also VOICEnnn.RSC

weight     Current weight of the object.

value     Current value of the object in Silver Pieces (10sp =
1gp).

x     Object's horizontal location (when not being carried).

y     Object's vertical location (when not being carried).

count     Number of objects represented by this single instance.

script     Optional script file. Uses OBJECT.SCR and CURRITEM.SCR
by default.

text     Object's text record (if any).

endgame     For compatibility with DCGAMES 1.x/2.x.. 0=No, 1=on
GET, 2=Give.

endtext     Text block # to be displayed when the game ends due to
'endgame'.

v0 - v7     Extra attributes, use for anything you want.

m0 - m4     Extra attributes, but you can have a token name
associated with one of these. See file DCCTOKEN.DAT for more
info.



World Variables and Attributes



Each world has a certain number of attributes which you can
examine and in some cases modify.  You can only access the
attributes for the world you are currently in.



Attribute     Description

name     Name of the current world, text, 15 chars.

index*     Current world number.

type     World's type, 0 - 255. Tokens: OUTDOORS, CITY, TOWN,
DUNGEON, HIDEOUT, HOUSE, CASTLE, ARENA and ENDGAME.

x*     Horizontal size (width) of the current world

y*     Vertical size (height) of the current world

block(x,y)     Landscaping block # displayed at position x,y

density(x,y)     Density of landscaping block at position x,y

level     Minimum player level needed to enter this world.

landscape     Landscaping file being used (0 to 9)

door     the door through which you entered the current world.

doorx(door#)     Horizontal location of the door in the current
world.

doory(door#)     Vertical location of the door in the current
world.

destinationworld(door#)     Destination world # .

destinationdoor(door#)     Destination door in the destination
world. (non-trap doors only)

destinationx(door#)     Horizontal location in the destination
world (trap doors only)

destinationy(door#)     Vertical location in the destination world
(trap doors only)

trapdoorswitch(door#)     Is non-zero if the door is a TRAP
(destinationx/y instead of destinationdoor).

 entrytext(door#)     Text block # displayed when the player enters
the world through the door.

entrytextswitch(door#)     If non-zero, the text is displayed only
the first time the door is used.

exittext(door#)     Text block # displayed when the player exits
the world through the door

exittextswitch(door#)     If non-zero, the text is displayed only
the first time the door is used.

edgedoor     The door through which the player exits the current
world by walking 'of-the-edge' of the world, or casting the
standard 'exit' spell.





Group Variables and Attributes

Durng game play, your group can contain anywhere from 1 to 6
characters.

Group Attributes     Description

size*     Current number of characters in the group.

current     Currently selected 'spokesbeing' for the group (0-5).

gold     Amount of gold being carried (given in silver pieces, 10sp
= 1gp).

food     The total amount of normal (non-magical) food being
carried by the party.

energy     The group's energy, which is replenished with sleep.

dead_count     Number of times that everyone in the group has died
(and thus, how many times they have been resurrected).

x     Current horizontal location in the current world.

y     Current vertical location in the current world.

moves     Total number of moves since the game started.

block     Tile # from DCSYSTEM.mde (type 'SYS_PARTY') to represent
the party during normal game play.

vehicle     Current vehicle (if any).  If the group is riding a
vehicle, the vehicle's graphics block is displayed instead of
the group's regular block.

Types of Scripts

This section talks about the different TYPES of scripts you may
want to write, and tries to point out WHY you would want to
write that kind of script, instead of HOW.  The actual script
language is presented in the section Script Language Programming
Guide later in this manual.

Introduction Script

The introduction script (INITGAME.SCR) is a script that is
executed only the first time you start playing. Like most games,
you must start of by telling the game player what the story is
about, give some background information, set the mood for the
game.

Before this script is invoked, a group with a single player is
created, taking the attributes from record 0 of the statistics
file (PLAYERS.DTA) as created using the DCWORLD program.

The INITGAME script is free to modify the default character, as
well as add other characters to the group at this time. It can
also invoke the edit_character function to allow the player to
select a name, character type, character block and starting
attributes.

You can also modify the group's starting position by seting the
X and Y attributes of the group variable, or by using the
teleport or enter commands.

A typical introductory script would look like this:

!

! FILE : initgame.scr

!



readtext( "intro.txt" );   ! Read some text

viewpcx ( "intro2" );      ! Show a nice picture

music   ( "intro2" );      ! Play background music

wait    ( 120 );           ! Wait until music ends or <SPACE> is
pressed



!

! Now, create the player's character by using 'edit_player'

!

  edit_player( 1,

               30, ! points to distribute

                9, ! Minimum start attribute value is 9

               25, ! Maximum start attribute value is 25

                1, ! Allow name to be changed

                0, ! Don't allow character class to be changed

                1  ! Allow character image to be changed

              );   ! Allow all stats to be changed (strenght,
dexterity, etc.)



CONTINUE;          ! Continue with normal character creation



Note that the READTEXT command has some voice, music and
graphics capabilities also.  The 'intro.txt' file does not
necessarily display a single page of text.

Character Script

Every character in the game has a script to control it's
behavior, except for monsters (type HOSTILE), whose behavior
consists of chasing the player and fighting.

The world builder assumes that the first 8 characters of the
character TYPE can be used as the name of the character's
script.  Thus a BARTENDER's script is BARTENDE.SCR, and a
BEGGAR's script is BEGGAR.SCR.

The system provides 11 predefined character scripts, each of
which has a unique function.  A full explanation of each
character 'type' as implemented by the scripts can be found in
the DCGAMES User's Guide.

Usually, a character script handles conversation.   When the
player 'talks' to a character, the character takes control of
the conversation by means of the script.  A merchant, for
example, asks if you wish to buy or sell something, while a
healer asks if you need to be cured, healed, etc.

Special characters may have their own unique script, as is the
case of JIMMY in the example adventure.  That script does a bit
of animation when the character is asked to join the adventurer,
and handles special needs of that character.

You should print out the character scripts and compare each of
them with the description of the character type as given in the
User's Guide. You will then understand how the given script
implements the behavior.

There are three ways of working with character scripts.  You can
modify the default scripts to alter the behavior of existing
character types, you can create a brand new character type, with
it's own script, or you can create a unique script for a unique
character.

Object Script

Unlike characters, objects are not requried to have a script
associated with them. If they do have one associated, it is
invoked first to allow it to handle the interaction. If the
script does not handle the interaction, or it does handle it but
ends with CONTINUE instead of STOP, or there is no script at
all, the system invokes one of the default object handling
scripts: OBJECT.SCR is invoked for objects laying around while
CURRITEM.SCR is invoked for objects being carried by the player
or npc.

Every time you create a new object type or even a new class
within an object type, you will need to modify the OBJECT and
CURRITEM scripts to handle the new object.  For example, mirrors
currently don't do anything.  If you wanted to have a mirror
that shows you an area around you, you could create mirror
classes.  Class 0 would be a normal mirror, while class 1 would
invoke a 'view' spell.  You can then modify the two scripts to
check the class attribute for mirrors and behave accordingly.

Note: Since version 4.0 allows one script to call another, this
description is not entirely correct. The CONTROL script calls
the OBJECT or CURRITEM scripts as needed, and these scripts may
call others, like the CASTING script or the DESCOBJ script.

Now, if you need to have a given object behave differently, you
need to write a separate script for it.  The script does not
need to handle all actions on that object, just the ones that
are different.  For example:  You want to create a magic ring,
but this ring can cast more than one spell.  You could write a
special script that has an entry point for the @WEAR action (see
the programming guide section at the end of this document).

When the character wears the ring, your script might display the
image of a genie, and ask the player what spell is desired.  The
script would then perform the appropriate spell.

Remember that if a script does not have an entry point for a
given action, then a default action is taken.  In this case, the
default action is to call the CURRITEM script.  Thus, all
actions would be handled by the CURRITEM script except for WEAR.

Remember also that if your script ends with CONTINUE instead of
STOP, the default action is taken anyway, so your script doesn't
really have to handle the situation.  For example, your 'ring'
may have a 'random' effect (i.e. you never know what is going to
happen when you wear it).  To do this, your script would just
set the ring's class (which determines it's magical effect) and
terminate with CONTINUE.  The default action would be taken, and
the CURRITEM script would handle the actual magical effect!World Script

World scripts are executed whenever you ENTER or EXIT the world.
 The default world script, WORLDDEF.SCR, is invoked if your
world does not have it's own script.  The world type and other
attributes configured using DCWORLD allow the WORLDDEF script to
handle most normal situations.

World scripts can be very powerful tools to introduce some
amount of 'sequencing' into the game.  From within a script you
can change landscaping, doors, etc.  You can also examine and
change every single object and character in that world.  You
could have a character that exists only after you have performed
a certain action.  The world script could check to see if you
have performed that action every time you enter the world, and
create the character only when you have done so.

You can even re-route the player to a different destination
within the same world, or in a totally different one.

See the comments in the WORLDDEF script for a detailed
discussion of entering and exiting worlds.

Control Script

The control script is the most sensitive script of all.  It is
called under different circumstances and it invokes most of the
other scripts itself as needed.

This script is invoked:

Every 'minute' of game play (as defined in the MovesPerMinute
control variable) to keep track of time and handle healing,
getting tired, resting, the appearance of random monsters, etc.

Every time you press a key or click with the mouse to handle the
interaction between the player and the game system.

Once for every player during a fight, to handle a player's TURN.

Once for every monster during a fight, to handle the monster's
TURN.

Note: Version 3.x had entry points in the control script for
handling a player leaving the party, winning a fight (for
experience and random treasure), etc. These entrypoints are no
longer needed because version 4.0 is more fully under script
control, so these events happen in their appropriate places
without special "hooks".

Resurrection Script

The resurrection script (RESURECT.SCR) is called whenever all
members of the playing party die.  From this script you have the
option to give the player a second chance. Once again, you have
complete control over the situation.  You can terminate the
game, give the player the option to restart, restore or quit, or
just restore the player's hit points and continue the game. You
can also transport the party to another location, and perform
some cleanup activities.

Writing Scripts

Script Files

A script can be written using any regular text editor or word
processor.  If you use a word processor, you should save the
script in ASCII or TEXT format (with no special controls like
fonts or page formatting).  The script file name should have an
extension of .SCR, to indicate it contains a script.

Once the script has been saved, you will use the script compiler
to translate the script from human readable form (text) into a
compact code that the game driver understands.  The translated
code is written into a file with the same name as the original
file, but with extension of .SCO (for SCript Object).

For example:

C:\DCGAME> edit myscript.scr

... you create the script using some editor ...

C:\DCGAME> dir myscript.*



 Volume in drive C is MYVOLUME

 Directory of C:\DCGGAME



 MYSCRIPT SCR      1208 10-29-92   1:25p

        1 file(s)       1208 bytes

                     6920192 bytes free



C:\DCGAME> dcc myscript

DCGAMES Script Compiler Version 4.0, August 1995

Copyright (c) 1992 DC Software, 7908 Kettlewood Court, Plano TX
75025

Compiling Script <myscript.SCR>

Code Size = 179

Data Size = 367

Labels    = 25

Compilation successful



C:\DCGAME> dir myscript.*



 Volume in drive C is MYVOLUME

 Directory of C:\DCGGAME



 MYSCRIPT SCO       604 10-29-92   1:28p

 MYSCRIPT SCR      1208 10-29-92   1:25p

        1 file(s)       1208 bytes

                     6920192 bytes free



The script MYSCRIPT is now ready to be used in your adventure.
Now, every script must be translated in the above manner
whenever you modify it, or the changes will not be seen by the
game driver. The game driver uses the .SCO file only.

To compile ALL the scripts in your current directory, type:

C:\DCGAME> for %i in (*.scr) do dcc %i

If you are familiar with any programming language at all, the
script language will be quite easy to learn, but even if you
have never learned any programming language, you should be able
to learn how to write scripts without to much trouble.

To assist you, the following section sections try to present the
script language in easy incremental steps, so you may learn at
your own pace.

If you get hopelessly lost, give me a call and I will try to
assist over the phone, but please give it your best shot and try
to have specific questions written down when you call.  It will
help keep the phone call as short as possible.

I urge you to annotate this document wherever you see think
something being presented poorly, in the wrong order, or just
plain wrong. This section is the most important one because it
is the one that enables YOU to write your games.  Send me a copy
of the pages on which you have made notes and I will gladly
correct the problem and send you back a new copy with
corrections as soon as they are made.

Expressions and Assignments

An expression is a list of one or more symbols that represent a
single value. The symbols may be variables, attributes,
constants, functions or operands.  We already know what
variables, attributes and constants are.  An operand is a symbol
that tells the computer that an operation should take place.
For example, in the expression 3 * 5 + 2, the * operand tells
the computer to multiply the constants 3 and 5, and the symbol +
tells the computer to add two values together..

In DCGAMES there are 3 types of expressions, arithmetic,
relational.

An arithmetic expression is one which takes numeric values (from
variables, attributes,  constant or functions) and performs an
arithmetic operation on them.  The arithmetic operands are: *,
/, +, - and % (this last representing a modulo operation, or the
'remainder' portion of an integer division).

A relational expression is one which compares two numerical
expressions and results in a logical value (to be specific, a
relational expression will always result in either a zero or a
one).

A logical value is either zero (meaning FALSE) or non-zero
meaning true.

Expressions are used in many places, but the most common use of
expressions is on the right side of an assignment statement.
The second most common use for expressions is as part of a flow
control statement, such as if or on, which are examined a bit
later.

Note that the function keywords listedat the begining of this
document can be used almost anywhere that you can use an
expresion. A function has a value which is replaced in the
position that you use the function itself.  It also may have
parameters that change the value of the function itself.

For example, the function abs( - 3 ) has a value of 3, while the
function max(-5,7,2) has a value of 7.

This table presents a more detailed description of the
functions, but a detailed explanation of each of them is found
in the Script Language Reference Manual.

Function Table

Function     Description

General     General purpose functions

abs(expr)     Returns the value of the expression without a sign
(removes negative signs)

adjustments(expr,...)     Returns the sum of the attribute
adjustments indicated by the expressions

find(where,what,type)     Find an object or character

getnum(str,low,high)     Display a message and get a value between
low and high from the player.

getstr(str,...)     Get a string from the player and return the
index of the matching one.

locate(what)     Locate an object or npc character by allowing the
player to point to it.

Time Related     Used to control time during game play

MovesPerMinute     Number of moves that can be made in one minute
of game play.

MinutesInAnHour     Number of minutes in one hour of game play.

HoursInADay     Number of hours in a day of game play.

DaysInAMonth     Number of days in a month of game play.

MonthsInAYear     Number of months in a year of game play.

Year     The current year.

Month     The current month of the current year.

Day     The current day of the current month.

Hour     The current hour of the current day.

Minute     The current minute of the current hour.

SunRise     The hour of the day at which the sun rises

SunSet     The hour of the day at which the sun sets

Monster Related     Used to create random monsters

DefStat(0-2)     Backpacks that contain likely treasure (usually
Potions, Rings and Staffs).

DefPack(0-3)     The statistics records for SMALL, MEDIUM, LARGE
and PIRATE monsters.

DefLandBlk(0-4)     Graphics blocks for land based monsters
(ordered, 0=Easy,4=Very Hard)

DefCaveBlk(0-4)     Graphics blocks for cave dwelling monsters
(ordered)

DefWaterBlk(0-4)     Graphics blocks for water dwelling monsters.
(ordered, 4=Pirate Ship)

DefSpookBlk(0-4)     Graphics blocks of skeletons, ghosts, etc.
(ordered)

expr represents any expression that results in a numeric value

... means that any number of the preceding may be listed,
separated by commas (up to 255 maximum)

The  numeric range (0-N) means that a value in the  given range
must be provided when referring to this variable



Examples:

! Increase a player's current level

player.level = player.level + 1;

! same as "inc(player.level);"



! When selling an object, increase the group's gold by half the
value of the object.

group.gold = group.gold - player.bp.value / 2;

! same as "dec( group.gold,player.bp.value/2);"



! Compute the amount of damage done by a weapon, taking into
account the wielder's

! strength (assumes this is not a missile weapon), where
strength is not important.

L25 = npc.weapon.damage + adjustments(npc.str);



! NOTE: Since relational expressions return 0 if false and 1 if
true, the following

!    expression returns a value between 0 and 7, which is the
number of attributes

!    of the current npc that exceed 25 points.

L7 = npc.str > 25 + npc.aim > 25 + npc.dex > 25 + npc.spd > 25 +

    npc.pwr > 25 + npc.iq > 25 + npc.chr > 25 + npc.luk > 25;



! Change the character's name to "Henry"

player.name = "Henry";



Please note that the last assignment statement assigns a string
value to the name attribute.  The name and script attributes may
only hold string values.

Statements

Just like the English language, the script language uses words
and symbols to build sentences or statements which tell the game
driver what to do.  A statement is a complete sequence of words
and symbols that tell the game driver how to perform a single
given action.

A complex statement consists of a one or more statements that
are grouped together in some fashion to create a more complex
one. You are already acquainted with the assignment statement,
now let's look at some other ones, grouped by their nature or
intended usage.

Conditional Statements

In most cases, rather than just assign values to variables, what
you want to do is take different action depending on certain
conditions:

! Compute the amount of damage done by a weapon, taking into
account the wielder's

! strength IF the weapon is a contact weapon (i.e. not a missile
weapon).

if npc.weapon.class = BLUNT or npc.weapon.class = EDGED then

    L25 = npc.weapon.damage + adjustments(npc.str);

else

    L25 = npc.weapon.damage; ! No adjustment for strength

endif;



! The above might also be accomplished as follows

L25 = npc.weapon.damage;

if npc.weapon.class = BLUNT or npc.weapon.class = EDGED then

    L25 = L25 + adjustments(npc.str);

endif;



! Now, the following statement displays the current health
status of a player

if player.hp = 0 then

    writeln( player.name, " is dead!" );

elsif player.hp = 1 then

    writeln( player.name, " is unconscious" );

elsif player.hp < player.mhp

    writeln( player.name, " is hurt, but still able to function" );

else

    writeln( player.name, " is healthy" );

endif;



Flow Control Statements

Sometimes, the if statement can result in long and difficult to
read statements.  In some cases, it is more appropriate to use
one of the various forms of the goto or gosub statements to
accomplish the same goal.

In order to use these statements, you must first declare one or
more labels to which the flow of the execution may be
transferred.  The following examples are equivalent.

Flow control using if

:AGAIN

    L3 = getstr( "Sell", "Buy", "Talk" );

    if L3 = 0 then

        ! script for selling goes here

    elsif L3 = 1 then

        ! script for buying goes here

    elsif L3 = 2 then

        ! script for talking goes here

    else

        writeln( "What did you say?" );

    endif;

    goto AGAIN;  ! do it again and again, forever.



Flow control using on-goto

:AGAIN

    L3 = getstr( "Sell", "Buy", "Talk" );

    on L3 goto XSELL, XBUY, XTALK;

    writeln( "What did you say?" );

    goto AGAIN;

:XSELL

    ! script for selling goes here

    goto AGAIN;

:XBUY

    ! script for buying goes here

    goto AGAIN;

:XTALK

    ! script for talking goes here

    goto AGAIN;



When a script is large, a single if statement may be several
pages long.  It is easy to loose track of what you were trying
to accomplish.  The on-goto statement has the advantage of
breaking the logic into separate sections, each self contained
and self explanatory.   A more complete analysis of the goto,
gosub, on-goto and on-gosub statements can be found in the
reference guide.

Loop Control Statements

Whenever you need to perform the same operation multiple times,
a loop statement may come in handy.  The following code shows a
player giving a copy of everything in his/her backpack to the
npc character:

L6 = 0; ! Start with the first backpack object;

:DOIT

    setbp(player.bp, L6);        ! Select the Nth backpack object

    if player.bp.count then        ! If count non-zero, there is an object

        copy(player.bp,npc);    ! Give a copy of the object

    endif;

    inc( L6 );                 ! Same as L6 = L6 + 1;

    if L6 < 16 goto DOIT;        ! Repeat 16 times



The above code uses the goto statement to create a loop that
examines the 16 backpack locations for an object and then copies
the objects (if they exist) to the npc.

The while statement

The while statement simplifies loops by providing an easy way of
defining a loop without having to declare a label or writing an
IF statement.  Note that the test for L6 < 16 is made before the
statements inside the loop are executed.

L6 = 0;

while L6 < 16 do

    setbp( player.bp, L6 );

    if player.bp.count then

        copy( player.bp, npc );

    endif;

    inc( L6 );

endwhile;



The for statement

The for statement simplifies the loop even more by allowing you
to specify both the initial value, the final value and the
amount by which the control variable (L6) is to be incremented
(or decremented).  Thus, the loop becomes:

for L6 = 0 to 15 do

    setbp( player.bp, L6 );

    if player.bp.count then

        copy( player.bp, npc );

    endif;

endfor;



The foreach statement

To top it of, the foreach statement allows you to select in
sequence every element of a group.  In this case, the group is
the set of objects in the backpack.  The foreach loop is
executed once for each element in the player's backpack.  Empty
slots are not even selected, so no test is needed.

Note that if the backpack has NO elements, then the statements
inside the loop not executed.  This is the best way of examining
all the elements of a group.

foreach player.bp do

    copy( player.bp, npc );

endfor;



The foreach statement can select: a) All the characters in the
player's group, b) All the objects in a character's backpack, c)
All the objects a character is wearing,  d) All the character's
in the current world (but not in the player's group) and e) All
the objects in the current world (but not in anyone's backpack).

Object Manipulation Statements

As you saw in the examples above, sometimes you want to move or
copy objects from one place to another.

Move and Copy

When you move an object, it is removed from it's current place
and inserted in the destination, as long as the destination has
enough room for it.  If there is not enough room or the
destination character cannot carry the object, the object is not
moved.

The copy  statement works the same way, but does not delete the
object from the source, thus making a copy instead of moving the
object.

In both cases, you can specify how many objects you want to
move.  The command will move as many as the destination can
possibly hold.  If you specify that you want to move or copy
more objects than are available in the source, additional
objects are created.

Drop

When you drop an object, it is added to the list of objects in
the world that you are in.  The object will remain where you put
it.  There are no temporary objects in DCGAMES.

Output Statements

Write and Writeln

When you want to display a value, you have several ways of doing
it.  The most simple one is the write or writeln statement.
With this statement you can display all attributes and variables
as well as text.

The following example displays the time of day in the text
window (assuming that the day has an even number of hours).

if hour < HoursInADay / 2 + 1 then

    writeln( "The time is ", Hour, ":", Minute, "am" );

else

    L7 = Hour - HoursInADay / 2;

    writeln( "The time is ", L7, ":", Minute, "pm" );

endif;



Display

The display statement will show a list of items in the menu
window, with or without numbers or values associated with it.
It is useful when you need to show a list of items but are not
requesting user input.  The many forms of the display statement
are documented in the reference guide.

Input Statements

Frequently, when you display something you are asking the player
for directions;  During a conversation, you ask the player what
they want to talk about;  A merchant might display a list of
items and ask which you want to buy.

Getstr and Getnum

The getstr and getnum functions both return a number.  The
getstr function asks the user to type a string and searches the
list of strings you provided.  If a match is found, the command
returns the index of the matching string (i.e. which one
matched).  If no match is found, the function returns a -1.  In
any case, the string is stored in the string variable s0.

The getnum function displays a string and asks the user to enter
a value in a given range.  Only values in the range are allowed.
 If the user presses Esc instead of typing a number, the
function returns -1.

Select

The select function displays a menu identical to the one
displayed by display, but allows the user to select one of the
entries by using the arrow keys.  This function is used
extensively, and you should study it with care in the reference
guide.

Going Places

There are several ways in which characters and objects may move
under script control.

Animation

All characters and any object that is not being carried by a
character has a location within the world reflected by the x and
y attributes of that character or object.  From a script you may
modify these attributes and effectively move the characters or
objects within the limits of the world they are in.  You can
also change the block attribute to provide some additional
visual feed back (as long as the character is on screen).

A small example of animation is presented in the JIMMY.SCR file
in the example game.  When asked to join the party, Jimmy will
walk over to his chest and retrieve his weapons, armor and
money.  He will then walk back towards the player and join the
party.

Automatic animation WILL be eventually handled by the system, so
don't go writing animation routines for every character in your
game.  This kind of animation should be used in specific
instances where you want things to happen that the user must not
be able to prevent or should not have to do him/herself.

Entering Doors

The player's party may move from one location to another in
several ways.  The simplest one is to use the Enter command to
enter a door.  The party will be transferred to the world and
destination that the door leads to.

NOTE: The party will NOT be transferred to the new location
until the script finishes execution.

Teleportation

If you wish to transfer the player to a specific world, you may
use the Teleport command.  This command allows you to specify a
destination world (by number) as well as either a door in the
destination world through which you wish to enter, or the actual
x and y location at which the party should appear.  Thus, a door
need not be present in the destination world.

Advanced Topics

Entry Points

Whenever a script is invoked, execution of the script will begin
at a special label which is called an Entry Point.  The entry
points are labels of the form :@# where # is a number between 0
and 20, but, to make life easier, the labels have specific names
associated with them, which make it easier to remember them.
The entry points and the names associated with them are
different for each type of script, and are shown below:  You
should use the name form of the entry points unless you have a
very good reason for using the numbers.

For Character Scripts

@TALK        (0)    - Talk to the character

@DROP        (2)    - Character is being asked to leave the party

@CAST        (11)    - Character will try to cast a given spell.

For Object Scripts

@TALK        (0)    - Talk to an object.

@GET        (1)    - Move an object into the player's backpack.

@DROP        (2)    - Drop an object being carried.

@WEAR        (3)    - Wear an object.

@REMOVE    (4)    - Remove an object being worn.

@LOOK        (5)    - Look at an object.

@EXAMINE    (6)    - Examine an object carefully.

@INVOKE        (7)    - Invoke the magic in a magical object (ring,
amulet, etc)

@USE        (9)     - Use a generic object for whatever purpose it is
intended.

@EXIT        (10)    - The player's party wants to get out of a vehicle.

For World Scripts

@ENTER        (9)    - The player's party is entering the current world

@EXIT        (10)    - The player's party is leaving the current world

For Control Scripts

n/a            (0)    - Time Control Entry Point.

n/a            (1)    - Party wants to rest for the night.

n/a            (2)    - A member of the party wants to leave the group.

For Magic Spells

@CAST        (11)    - A magic user has casts a spell.

For Game Initialization

n/a            (0)    - Invoked at game initialization

For Dead and Resurrection

n/a            (0)    - Invoked when everyone in the party dies.

Calling A DOS program

From within a script, you may execute a DOS program by using the
system command.  This command works exactly like the writeln
command, except that instead of sending a line of text to the
text window, the text is formed into an MS-DOS command and
executed.  When the command ends execution, the MS-DOS error
level is stored in the failure variable.  A value of 0 usually
indicates success.

See the reference guide entry for additional information.

Creating New Types and Classes

When the current types and classes of characters, objects or
worlds is not enough, you may create your own types and classes
as needed.  The procedure for doing this is highlighted here,
the assumption is made that you have read the manuals and are
familiar with the script language before you attempt to add a
new type or class.

New Character Types

To create a new character type, you should edit the file
DCCTOKEN.DAT, look for the section [CHARACTER TYPES and add an
entry after the last character type in the file:



[CHARACTER TYPES]

REGULAR         0 ! REGULAR.SCR  - Will join the party if asked
to..

HOSTILE         1 ! HOSTILE.SCR  - Will attack on sight and
follow you..

MERCHANT        2 ! MERCHANT.SCR - Buys and Sells stuff..

BARTENDER       3 ! BARTENDE.SCR - Sells beer.  Good source of
information.

HEALER          4 ! HEALER.SCR   - Cure, Heal, Resurrect, Remove
Curse,..

CIVILIAN        5 ! CIVILIAN.SCR - Will talk, but won't join..

TELLER          6 ! TELLER.SCR   - Fortune Teller or Oracle
type..

QUESTER         7 ! QUESTER.SCR  - Asks you to find an object or
person.

BEGGAR          8 ! BEGGAR.SCR   - Want's money.  Might give you
a tip.

TRAINER         9 ! TRAINER.SCR  - Will train someone
(STR,DEX,AIM,IQ)

GUARD          10 ! GUARD.SCR    - Blocks your way unless given
the password.

PRISONER       11 ! PRISONER.SCR - Will join your party
temporarily (to escape).

LAWYER         12

In the above segment, the new character type LAWYER has number
12 assigned to it (the next available number).  You may now
write a script file called LAWYER.SCR to handle the default
behaviour of lawyers.

New Character Classes

Character classes in the current implementation apply only to
characters that join the party.  The class of the character is
used to determine what kind of weapons and armor they can use,
what kind of magic they have, how fast they recover, etc.

To create a new character class, just edit the DCCTOKEN.DAT file
and add the new class to the [CHARACTER CLASSES] section:



[CHARACTER CLASSES]

HUMAN           0 ! standard stuff, no power

ELF             1 ! fast, magical power, not strong

DWARF           2 ! slow, STRONG, no magic, no missiles or
shields

WIZARD          3 ! slow, lot's of magic, not strong

ARCHER          4 ! fast, no magic, + on missile weapons

FIGHTER         5 ! fast, strong, no magic of any kind

THIEF           6



In the above segment, the new character class THIEF has a number
6 (next available one).

The DCBLOCK, DCWORLD, DCPLAY and DCREPORT programs will now
recognize thieves as a valid character type.

You may also want to modify the OBJECT and CASTING scripts to
give a thief certain advantages when dealing with traps, and to
enable or restrict the kinds of weapons, magic, etc, that the
character can handle.

New Object Types

Creating a new object type is again started by adding the new
type to the DCCTOKEN.DAT file.  The section [OBJECT TYPES]
contains the names and numbers for all object types.

Unlike characters, a single script handles all object types and
classes.  The OBJECT script should be extended to handle the new
object type for all it's entry points.

The object types Food, Weapon, Armor, Shield, Amulet, Ring and
Staff have special treatment because they can be worn by the
characters.  The Vehicle  object type also has special handling
because it can be used for transportation.  Other than these
special handling, you can modify the OBJECT script file as much
as you want.

New Object Classes

An object class is also represented by a section in the
DCCTOKEN.DAT file.  It is different from other sections in that
multiple object types may have the same class (for example:
rings, amulets, food, potions and gems all have the same class
set).

If your new object is going to have the same set of class items
that already exists for another type, just add the name to the
list, for example:

!

! Magical Effects, Type 1

!

[OBJECT CLASS: FOOD, POTION, RING, AMULET, GEMS, WIDGET]

NONE            0 ! No magical effect

CURE            1 ! Remove POISON

HEAL            2 ! Restore some HP

POISON          3 ! (Trap) POISON drinker

RESTORE         4 ! Restore ALL HP

PLUS_STR        5 ! Increase STRENGTH

PLUS_DEX        6 ! Increase DEXTERITY

PLUS_SPD        7 ! Increase SPEED

PLUS_AIM        8 ! Increase AIM

PLUS_AC         9 ! Increase AC

PLUS_HP        10 ! Increase HP

PLUS_IQ        11 ! Increase IQ

PLUS_PWR       12 ! Increase POWER

Here, we have added the new object type WIDGET to the set of
objects that have personal magic.

You still have to modify the OBJECT script to handle the
object's class.  For example,



  on object.type goto

   USE_FOOD,     USE_WEAPON,     USE_AMMO,      USE_ARMOR,
USE_SHIELD,

   USE_AMULET,   USE_RING,       USE_POTION,    USE_SCROLL,
USE_STAFF,

   USE_CHEST,    USE_KEYS,       USE_GEMS,      USE_BOOK,
USE_GOLDSACK,

   USE_TORCH,    USE_LANTERN,    USE_ROPE,      USE_HOOKS,
USE_MIRROR,

   USE_SIGN,     USE_VEHICLE,    USE_WIDGET;

  .

  .

  .

  :USE_AMULET

  :USE_RING

  :USE_ARMOR

  :USE_WEAPON

  :USE_SHIELD

  :USE_STAFF

     writeln( "You must first 'get' it, then 'wear' or 'wield'
it.." );

     STOP;

  :USE_WIDGET

     writeln( "If you want to use it, you must first 'get' it.."
);

     STOP;

  .

  .

Here, we have decided that a WIDGET must be in the player's
backpack before it can be used.

If your new object is different from all other objects, you can
create a brand new section for it's classes in the DCCTOKEN.DAT
file:

!

! My WIDGET object classes

!

[OBJECT CLASS: widget]

ROUND        0 ! A round widget

SQUARE    1 ! A square widget

OVAL        2 ! An oval widget

At this point, you may create graphics blocks with type widget
and class round, square or oval.  You may also write script code
like this:

if object.type = widget then

  on object.class goto XROUND, XSQUARE, XOVAL;

  writeln( "Unknown widget class.." );

  stop;

endif;

:XROUND  ! Handle a round widget

 ....

 STOP;

:XSQUARE ! Handle a square widget

 ....

 STOP;

:XOVAL   ! Handle an oval widget

 ....

 STOP;

New Object Modifiers

Each object has 5 attributes that can be used to implement it's
differences from other objects.  These attributes have names m0
through m4, but the object modifiers section in the DCCTOKEN.DAT
file allows you to call them by other names.

When you create a new object type and/or class, you may want to
create new names for those fields that you might use to
differentiate between them  For example:

[OBJECT MODIFIERS]



! Object Type: FOOD

!          0   Is not used

UNITS      1 ! If magical, how many units are affected

PERMANENT  2 ! If magical, how long does effect last? (0=one
day, 1=permanent)

!          3   Is not used

!          4   Is not used



! Object Type: WEAPON

HANDS      0 ! # of hands needed to use the weapon

RANGE      1 ! Range of this weapon

DAMAGE     2 ! Damage done when using this weapon.

AMMONEEDED 3 ! Type of ammunition needed (See AMMOTYPE below..)

!          4   Is not used



! Object Type: WIDGET

SIDES      0 ! # of sides that the widget has

RANGE      1 ! Range of this widget



Note that if you want to use a token that already has a value
assigned, like range in the example, which has a value 1
assigned for weapons, you MUST use the same value for the token.
Tokens are replaced by their numeric value during compilation,
so the following two lines are equivalent:

if object.hands = 7 then ...

if object.sides = 7 then ...



Both lines are comparing the m0 modifier of the object with the
value 7.  The type of the object is not checked to see that the
token you are using belongs to the object's type.

New World Types

Perhaps the easiest to create would be a new world type.  Again,
just add the entry to the DCCTOKEN.DAT file, section world
types,  and then edit the WORLDDEF script file to handle the new
world type.

Note that many of the currently defined world types have no
actual differences between them.  For example, Cities, Towns,
Hideouts, Houses and Castles are all the same..  You can change
that by modifying the appropriate scripts.

For example: If you want to make opening a locked chest a crime
in Castles and Houses, you can add a check in the OBJECT script
to verify the type of world you are in when the character tries
to break a lock.

Shareware Opportunities

While most users will use the script language to make small
changes to the game system, with a few customized scripts to
handle special characters or objects, the true power of scripts
lies in the ability to completely change the way everything
works.  Here are a few example of some more complex projects
that you may want to attempt once you are comfortable writing
scripts:

Extending the magic system



The current magic system allows a character to cast a spell if
it has the required number of power points.  There is no
requirement to learn the spells, or to be at a certain level
before you can cast it.  You can change the OBJECT and CASTING
scripts to handle a magic book, which can be either a class of
book (currently, books don't have classes) or a whole new type
of object (Magic Book).

You can also change the scripts to handle a lot more spells (up
to 255 of each type), or add a level requirement for each spell.

MS-DOS based extensions

The system command allows you to run DOS programs from within a
script.  The following DOS programs could be called from a
script to extend the functionality of the system.  Writing these
extensions requires knowledge about internal structures of the
game files, which I will be glad to provide on a case by case
basis.

Save/Restore/Restart

Replace the prompts that perform this function with a window
that shows saved games along with comments and let's you choose
which one you want to restore, or lets you specify which slot
you want to save in, and what comment you want to associate with
the saved game.

Character Editor

Allows you to examine/modify (i.e. cheat) the PARTY file.

Arcade/Casino extensions

A completely separate sub-game that is executed when you enter a
world.  For example, when you enter a casino, you can run a DOS
game that allows the user to play poker or some other games in
order to make money.  The program may read the PARTY file to get
the names of the characters and the amount of gold they have.
It would update the gold amount when the characters leave the
casino.

Stand Alone Utilities

A nice utility would be one that can take the game and create
PCX graphics files for each world, optionally including the
objects and characters that appear in it.  The PCX file can then
be scaled and manipulated by other utilities to print maps or
include the graphics in documentation.

Writing a whole new system

It is perfectly feasible to take the rules, character types,
magic system, etc of game systems such as Dungeons and Dragonstm
or Man, Myth and Magictm and write them as scripts.  You would
have to throw away all of the current scripts and write them
from scratch, but it's perfectly feasible. Of course, these
systems are copyrighted by their respective publishers, so it
wouldn't be possible to distribute such a system as shareware (I
think, but I'm not a copyright expert).

Primary Keywords

continue

copy

dec

display

drop

endgame

enter

fight

find

for

foreach

frame

getaction1

getnum

getstr

goto

gosub

if

inc

join

leave

loadhint

loadtext

locate

move

on

paint

pause

readtext

restart

restore

return

runscript1

save

savepcx1

select

setbody

setbp

stats

stop

teleport

vanish

viewfli1

viewpcx

voice

vplay

wait

while

write

writeln



Secondary Keywords

if

- then, elsif, else, endif

expression

- and, or, xor, not

for

- to, by, do, endfor

foreach

- do, endfor

while

- endwhile

select, display

- matching

paint

- screen, window



Function Keywords

abs

action

adjustments

Day

DaysInAMonth

DefCaveBlk

DefLandBlk

DefPack

DefSpookBlk

DefStat

DefWaterBlk

fighting

failure

Hour

HoursInADay

keypress1

max

min

Minute

MinutesInAnHour

Month

MonthsInAYear

MovesPerMinute

pointx1

pointy1

random

success

SunSet

SunRise

version

Year

1 Keywords marked with a (1) are new in version 4.0 of DCGAMES!