Threading, Async, and timers#

When using timers or infinite statements such as while(true) or wait it is important to use thread before the function in order to prevent crashes or freezes.

What is thread?#

The thread term is used to tell squirrel to run the following function separately from the rest of the game, while in a simple scripts code is run sequentially(line 1,2,3 etc) if a line of code would last forever or need to function in parallel to normal gameplay, such as a wait command, it is important to use thread or the game will get stuck processing that line indefinitely and will not move to the next lines, causing crashes or freezes.

How do i use thread?#

Using thread is fairly simple, if we have a function called delayannouncement that chooses one player as “it” 10 seconds after spawning we cannot use this function on its own, instead calling it with a thread by simply calling

thread delayannouncement()

The same applies to a while(true) function, for example almostover a function that checks every 5 seconds to see if the game has 2 or less minutes left and announces it if so.

thread almostover()

Example Script#

lets try implement both of our scripts from the previous 2 sections, as well as a callback to trigger the script.

First, lets add our callback to the gamemodes core function.

global function GamemodeTag_Init


void function GamemodeTag_Init(){
AddCallback_GameStateEnter( eGameState.Playing, MatchStart )
}

Then lets define the function matchstart and have it simply thread our two important functions.

void Matchstart{
    thread delayannouncement()
    thread almostover()
}

This script waits 10 seconds, picks a player and announces that player as “it” however being it currently does nothing, we will define that later.

void delayannouncement(){
wait 10.0
string chosenplayer = GetPlayerArray()[RandomInt(GetPlayerArray().len())]
string message = chosenplayer + " is it!"
foreach ( entity player in GetPlayerArray() )
    SendHudMessage( player, message, -1, 0.4, 255, 0, 0, 0, 0, 3, 0.15 )
}

This function will now repeat endlessly, waiting 5 seconds before each repeat. make sure to add a return or break statement to prevent the message looping every 5 seconds after, unless you want that

void almostover(){
    while(true){
        if(GameTime_TimeLeftSeconds() < 120){
            foreach ( entity player in GetPlayerArray() )
                SendHudMessage( player, "Two minutes left!", -1, 0.4, 255, 0, 0, 0, 0, 3, 0.15 )
                break
            }
            wait 5.0
        }
    }

You have now created and threaded both functions.