scripting syntax

General rules

1. Execution starts in the main function (main is just a normal function).
   
   
2. A function must be declared before it is used:
   This means either the entire function has to be located before any calls to it or you have to add a function declaration for it (preferably at the top of the file). A function declaration is just the header part with a semicolon at the end.
   
   For example: set_fade_color( int color );
   
   
3. You need a ; at the end of each command
   
   
4. Including other files:
   Format : #include “filename”
   For example: #include “scripts/utils.scr”
   
   
5. Comments:
   // comments out everything to the right of the // on this line only
   /* */ comments out everything between the /* and the */

Functions

All functions adhere to this general format:

return_type function_name( paramtype parameter1, paramtype parameter2 )
{
commands;
}

For example:

void set_sky_color( float sky_color )
{
global_sky_color = sky_color;
}

The function declaration for the above example would be as follows:

void set_sky_color( float sky_color );

There are two ways to call a function:

• function();
  This calls the function and stops execution of the calling function until the called function returns.
  
  
• thread function();
  This calls the function with a new thread so that the calling function/thread can keep going.

Calling format:

function_name( parameter1, parameter2 );

The number of parameters is determined by the function declaration. Functions can return values.

For example:

color = get_sky_color();

Entities

Map entities are referenced like this:

$entity_name.command_name( parameters );

For example:

$monster1.attackplayer();

Only use the dollar sign ($) if the referenced entity is a map entity. If you are using a normal entity variable don’t use the dollar sign.

It is possible to get a variable for an entity if you know the name of it as follows:

entity temp_entity;
temp_entity = getentity( entity_name );

Basic language commands

while
Loops until the while condition equals 0 or false. This is checked at beginning of each loop.

Format:

while( condition )
{
commands
}

For example:

while( waveindex <= 15 )
{
thread WAVE();
wait( 1 );
waveindex = waveindex + 1;
}

do/while
Loops until the while condition equals 0 or false. This is checked at end of each loop.

Format:

do
{
commands
} while ( condition );

For example:

do
{
thread FLIP_ARCH_STEPS( "archstep", stepindex, stepheight );
wait( 0.5 );
stepindex = stepindex + 1;
stepheight = stepheight - 25.6;
} while( stepindex <= 15 );

for
This looping construct executes until condition is false.

Format:

for( init commands ; condition ; per loop commands )
{
}

The init commands are evaluated just once, usually to initialize variables. Then the condition is evaluated - if it is false, the statement terminates, and if it is true, the statement executes. After that, the per loop commands are executed and the loop starts over.

For example:

for( t = 0; t < endtime; t++ )
{
i += t;
}

if/else
This loop executes a block of commands if the condition is true. If false it executes the block of commands after the else (else part is optional).

Format:

if ( condition )
{
commands
}
else
{
}

For Example:

if ( sky_color == 1 )
{
new_color = 2;
}
else
{
new_color = 1;
}

return
Returns from the current function/thread and optionally returns a value.

Format:

return; or
return value;

scripting commands

Please see the Game Module Classes reference for a list of scripting commands.

Variable types available

• float - a floating-point number.
• vector - composed of 3 floating point numbers, written as 'x y z'.
• entity - an entity that exists in the game.
• string - a string, written as "characters".
• void - no return type.

Math operators

• +=
  Equivalent to x = x + y; (works for strings as well)
  
  
• -=
  Equivalent to x = x - y;
  
  
• *=
  Equivalent to x = x * y;
  
  
• /=
  Equivalent to x = x / y;
  
  
• ++
  Increments variable by one.
  
  
• --
  Decrements variable by one.
  
  
• *
  Multiplication.
  
  
• /
  Division.
  
  
• -
  Subtraction.
  
  
• +
  Addition (works for strings as well).
  
  
• =
  Sets variable equal to.
  
  

Comparison operators

• <
  Tests if less than.
  
  
• >
  Tests if greater than.
  
  
• <=
  Tests if less than or equal.
  
  
• >=
  Tests if greater than or equal.
  
  
• ==
  Tests if equal.
  
  
• !=
  Test if not equal.
  
  

Logic operators

• &&
  AND
  
  
• ||
  OR
  
  
• !
  Logical negation (true if argument to its right is false, false otherwise).

Bit operators

• &
  Bitwise AND a variable.
  
  
• |
  bitwise OR a variable.
  
  
• &=
  equivalent to x = (x & y);
  
  
• |=
  equivalent to x = (x | y);
  
  

Format operators

• ;
  All statements must end in this.
  
  
• ,
  Used to separate function arguments.
  
  
• (
  Opening for a function call, grouping for mathematical functions.
  
  
• )
  Closing for a function call, grouping for mathematical functions.
• #
  Prefix for #include and #define.
  
  
• ...
  
  
• .
  
  
• [
  Opening for array index.
  
  
• ]
  Closing for array index.
  
  
• {
  Opening for a block of statements.
  
  
• }
  Closing for a block of statements.