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| Suspends execution of [[Scheduler | scheduled]] script until the given condition satisfied. This command will loop and call the code inside <tt>{}</tt> ''mostly'' every frame (depends on complexity of condition and overall engine load) until the [[Code|code]] returns [[true]]. The execution of the rest of the script therefore will be suspended until [[waitUntil]] completes. <br><br> | | Suspends execution of [[Scheduler | scheduled]] script until the given condition satisfied. This command will loop and call the code inside <tt>{}</tt> ''mostly'' every frame (depends on complexity of condition and overall engine load) until the [[Code|code]] returns [[true]]. The execution of the rest of the script therefore will be suspended until [[waitUntil]] completes. <br><br> | ||
If the very first execution of the code returns [[true]] the command will exit immediately, therefore it will not produce any "Suspending not allowed in this context" error when used inside [[Scheduler#Unscheduled_Environment|non-scheduled]] script. For all other uses it must be executed in environment that allows [[Scheduler#Suspension|suspension]] ([[canSuspend]]), such as [[spawn]]ed or [[execVM]]ed code. | If the very first execution of the code returns [[true]] the command will exit immediately, therefore it will not produce any "Suspending not allowed in this context" error when used inside [[Scheduler#Unscheduled_Environment|non-scheduled]] script. For all other uses it must be executed in environment that allows [[Scheduler#Suspension|suspension]] ([[canSuspend]]), such as [[spawn]]ed or [[execVM]]ed code. | ||
{{ | {{Feature | important | Since Arma 3 v1.93.145618, a ''condition'' returning anything other than [[true]] or [[false]] '''will''' result in an appropriate type error.}} | ||
|pr= For some unknown reason if you have [[waitUntil]] loop active and game is '''saved/loaded''', some variables in the expression may appear undefined for a short time. As a workaround, assign expression to a variable and make sure it is defined before [[waitUntil]] checks it: | |pr= For some unknown reason if you have [[waitUntil]] loop active and game is '''saved/loaded''', some variables in the expression may appear undefined for a short time. As a workaround, assign expression to a variable and make sure it is defined before [[waitUntil]] checks it: | ||
<code>[[waitUntil]] { [[private]] _expression {{=}} var1 && (var2 > 10); ![[isNil]] "_expression" && { _expression } };</code> | <code>[[waitUntil]] { [[private]] _expression {{=}} var1 && (var2 > 10); ![[isNil]] "_expression" && { _expression } };</code> |
Revision as of 02:12, 7 February 2021
Description
- Description:
- Description needed
- Problems:
- For some unknown reason if you have waitUntil loop active and game is saved/loaded, some variables in the expression may appear undefined for a short time. As a workaround, assign expression to a variable and make sure it is defined before waitUntil checks it:
waitUntil { private _expression = var1 && (var2 > 10); !isNil "_expression" && { _expression } };
- Groups:
- Program Flow
Syntax
- Syntax:
- Syntax needed
- Parameters:
- condition: Code - the expression that must return a Boolean, true to finish waiting or false to continue waiting
- Return Value:
- Return value needed
Examples
- Example 1:
waitUntil { not alive player };
- Example 2:
_i = 0; waitUntil { _i = _i + 1; _i >= 100 };
- Example 3:
waitUntil {sleep 1; not alive player }; // Checks every 1 second
- Example 4:
- An on-the-fly custom event handler:
_myEH = ["ZoomIn"] spawn { while { true } do { waitUntil { inputAction (_this select 0) == 1; }; diag_log format ["%1 @ %2", _this select 0, diag_tickTime]; }; };
Although perhaps better to use onEachFrame, depending on the application. - Example 5:
- Use getVariable with default value:
// bad waitUntil { bank getVariable "money" > 0 }; // good waitUntil { bank getVariable ["money", 0] > 0 };
// bad waitUntil { isready }; // good waitUntil { missionNamespace getVariable ["isready", false] };
Always return Boolean:// bad waitUntil { if (not alive player) exitWith {}; _time = _time + 1 }; // good waitUntil { if (not alive player) exitWith { true }; _time = _time + 1; false }; // perfect waitUntil { not alive player };
Additional Information
- See also:
- See also needed
Notes
-
Report bugs on the Feedback Tracker and/or discuss them on the Arma Discord or on the Forums.
Only post proven facts here! Add Note
- Posted on December 20, 2006 - 19:55
- CrashDome
- waitUntil suspends both SQF functions and SQF scripts. In functions, the calling script is still in suspension due to waiting for a return from the call command. The game engine will continue, however. See Function for more detail.
- Posted on April 2, 2010 - 17:10
- Roehre
- Prior to Arma 3 v1.92.145618 if waitUntil uses an undefined call code, waitUntil won't release, even when this code is separated from other conditions through or. Be warned that this won't cause an error message.
- Posted on Jan 07, 2011
- kju
- By default the cycle time for the condition check is per frame. Look at the example 3, how to set it at a lower rate yourself. Often times one does not need per-frame checking. Saves a lot CPU checks; especially when the condition is complex to compute.
- Posted on December 13, 2014 - 23:25 (UTC)
- Commy2
-
If you want to use waitUntil together with exitWith, remember that the loop only exits if the code block returns true.
It should look like this:waitUntil { // exit loop if the unit gets deleted {{cc|if (isNull _unit) exitWith { true }; // has to return true to continue !alive _unit; };