This function triggers a callback function after the specified time or after a certain interval. It does this by creating a Time Source (see Time Sources).
To cancel the callback function, see call_cancel.
IMPORTANT While this function returns an actual time source, it cannot be used with the time source functions, as the time sources used by call_later and call_cancel are "invisible" - they will not appear as children of any built-in time sources and cannot be used with other time source functions. They are, however, included in the time source count returned by debug_event("ResourceCounts").
The following is a breakdown of this function's arguments:
This is a period of time that may be expressed in seconds or frames, depending on the unit specified in the next argument.
When using frames as the unit, the period must be an integer. Non-integer values are rounded down (floored), with the exception of values lower than 1, which are rounded up to 1.
This is the unit that the period is expressed in, and may be time_source_units_seconds or time_source_units_frames.
See: Time Source Units
You can use a beats-per-minute value by using time_bpm_to_seconds().
You must specify a "callback" method that is called when the Time Source expires.
Whether the time source should loop.
call_later(period, unit, callback, [loop=false]);
| Argument | Type | Description |
|---|---|---|
| period | Real | The period that the Time Source runs for, in the given units |
| units | Time Source Unit Constant | The units that the given period is in |
| callback | Method or Script Function | The method or script function to call after the specified time |
| loop | Boolean | OPTIONAL Whether to loop the Time Source (default is false) |
var _callback = function()
{
show_debug_message("Five seconds have passed!");
}
var _handle = call_later(5, time_source_units_seconds, _callback);
In this example, we create a callback function that shows a debug message after five seconds have passed. After that, the underlying Time Source is destroyed.
var _create_enemy = function()
{
var _x = random(room_width);
var _y = random(room_height);
instance_create_depth(_x, _y, depth, obj_enemy);
}
var _handle = call_later(10, time_source_units_seconds, _create_enemy, true);
In this example, we create a callback function that creates a new enemy at a random position in the room. This function is then executed every 10 seconds by passing it to call_later. The last argument is set to true so the function keeps getting called every 10 seconds.
Use call_cancel with the handle returned by call_later to stop the Time Source and the calls to the callback.