Script (File)

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A script is a chunk of code grouped together in a seperate textfile. This code does a specific task handled by the game engine. The common extensions for scripts are .sqs and .sqf, depending on the used syntax (see below). You can use any text editor like Notepad to edit scripts.

A special kind of a script is a function.

Contents

Usage

Scripts are mainly used for any game processes where timing is important. They are unlike functions where the result or calculation is important.

Thus scripts can be used for cutscenes, dialogs, radio scripting and much more.

Syntax

Scripts can use two different formats: The older (and depreciated) SQS Syntax, as well as the newer and more powerful SQF Syntax.

Execution

Script Execution Diagram

Executing Instance: script, function or game engine

Scripts can be executed from several points in the game:


The commands to execute scripts are:

exec
exec starts a thread for a script in SQS Syntax.
execVM
execVM compiles a script in SQF Syntax and starts a thread for it.
spawn
spawn starts a thread for compiled Code and returns a script handle.


Note: The following statements do not apply for functions.

Scripts run alongside (parallels) the executing instance in their own threads. That means that the executing instance (i.e. script or function) doesn't wait for the script to end. This means scripts should not be used for code that should return a value used in the calling script. This is done by functions.

Scripts return a script handle which you can use to verify whether a script is still running.

Special Variables

_time in both syntax ?

Special Commands

Due to the fact, that calling instances aren't waiting for the scripts to end, scripts can be halted for a custom period of time. There are different methods to do this in SQF Syntax and SQS Syntax.

SQF syntax

Delay
You can set the script to sleep for a number of seconds using the command sleep.
STATEMENT 1;

// wait 10 seconds
sleep 10;

STATEMENT 2;
Waiting for a condition
You can set the script to sleep until a specific condition is met using the command waitUntil.
BOOL = false;

// wait until BOOL gets true
waitUntil BOOL;

STATEMENT;

SQS syntax

Delay
You can set the script to sleep for a number of seconds by introducing a line with ~, followed by the number of seconds.
STATEMENT 1

; wait 10 seconds
~10

STATEMENT 2
Waiting for a condition
You can set the script to sleep until a condition is met by introducing a line with @, followed by the condition.
BOOL = false

; wait until BOOL gets true
@BOOL

STATEMENT
Waiting for a time
You can set the script to sleep until a time (number of seconds since the beginning of the script) is met by introducing a line with &, followed by the time.
&100

; is equivalent to 

@_time >= 100

See also

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