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Using schedule() and cancel()

by Gabe Allen · 07/17/2002 (9:10 am) · 16 comments

At some point, you're going to need to continually run a function based upon a certain amount of time. That's where schedule() comes in.

I've made a few changes based on the comments I got. One thing (basically the repetition) I knew, but I was still thinking in that mindset when I wrote this. So I got that cleared up (thanks Brett). I also added in how to pass variables (thanks Matt).

In my case, I was trying to alter the turning speed of a player based upon their current velocity. This meant I needed to re-evaluate the player velocity constantly while the turn key was depressed. I had virtually no idea how to do this. When I explained what I was trying to do, Ed Gardner mentioned schedule(), so I went off in search of information on how to useit. Unfortunately, I didn't find much. But between the original schedule() forum post and Panama Jack's speed HUD, I managed to figure out how to do what I needed to do.
I'll say right now that I don't know how to use this with objects. If anyone does, please post comments so I can update this.

Your basic usage : schedule(%time, %object, %command)

%time is a value in milliseconds that specifies when it will run %command.

For the purposes of this HowTo, %object should be entered as 0

%command is the name of a function that you want to run

Example : schedule(1000,0,bustAction);

This will execute the bustAction() function after one second. By placing your schedule inside the bustAction() function, it will execute every second. Using schedule(1000,0,bustAction(somethingHere)); is a quick way to get back to your desktop. Instead use schedule(1000,0,bustAction,%variable,"string",#);

If you're going to have schedule called repeatedly, you're going to need a way to stop it from exectuing. This is where cancel() comes in. But in order to use it, we have to change the way that we call schedule().

Example : $someVariableName = schedule(1000,0,bustAction);

This effectively gives your scheduled event a name. In order to stop your scheduled event, use cancel($someVariableName);

Hopefully someone will find this useful. If anyone has any questions or comments, please post them (as several of you have!) and I'll get back to you.
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Torque Owner Gabe Allen

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Torque Owner Matt Webster
#1
07/18/2002 (4:43 am)
schedule(1000,0,bustAction,variableOne,variableTwo);

Just put variables after the function, and it should work. I haven't worked with it in a while, but the radar used to work like that before it was hard-coded.

Torque Owner Will Sanders
Default Studio Name
#2
07/18/2002 (4:57 am)
Thanks in advance! You probably saved my team and I a few days/weeks of searching.

Brett Michael
#3
07/18/2002 (5:47 am)
Schedule() only runs once.

ie. schedule(1000,,) will fire in one seconds time.

if you wanted it to fire every second you would require it to call a function which then rescheduled iteself.

I'm not sure if you knew this, sorry if you did, but you talk about it as if it runs continually.

Regards,
Brett

Torque Owner Gabe Allen
#4
07/18/2002 (8:01 am)
Made a couple of changes there .. thanks guys.

Matt : Yep. You can pass stuff just fine like that. Thanks.

Brett: like I say in the update, I just got kinda stuck on that one use because that's what I was doing at the time. I even used it as a one shot deal in my code, which makes me feel really dumb :)

Torque Owner Lucas Goodwin
#5
07/21/2002 (12:05 am)
An old trick from Tribes 1 :)

I used it heavily in T1, even to add ground vehicles (though ofcourse the code lagged the server to all hell).

Torque Owner Daniel Neilsen
#6
07/22/2002 (3:36 pm)
For a tutorial on using schedule in both its native and object oriented form go here
www.liquid.nq.net/tutorial/

Torque Owner Wash U Student (15)
#7
10/28/2004 (7:56 pm)
I keep getting an error that says the method I'm passing is not found. I'm spelling it correctly and passing the all the arguements it needs, so I don't understand where I'm going wrong. Here is what I have:

function PlayGui::onMouseDown(%this, %aKeyModifier, %clickCount)
{
if (%clickCount == 1) {
$clickEvent = schedule(500, 0, PlayGui.onMouseDown, %this, %aKeyModifier, %clickCount);
}

Any ideas?

Torque Owner Moondog Spot
#8
04/03/2005 (6:39 pm)
Gabe,
Thanks for putting this together. I spent the better part of a day combing through the forums looking for this info.

Torque Owner Suryadiputra Liawatimena
#9
08/08/2005 (4:05 am)
ok great i need these kind of documentation heheh.

Associate James Ford
Sickhead Games
#10
06/04/2006 (10:40 am)
what is the "object" position for--the paramenter that is always 0?

Torque Owner Caleb
Default Studio Name
#11
06/10/2006 (9:09 am)
This Helps Alot!
THANKS!!

Torque Owner Rob Riddell
#12
08/05/2006 (1:54 am)
Super! Saved me much time

smiles . . .

Nick
#13
12/22/2006 (11:28 am)
Do you guys have any idea how to cancel schedule() in this situation:

function rotateShape(%shape)
{
%transformInfo = %shape.getTransform();
%pos_x = getword(%transformInfo, 0);
%pos_y = getword(%transformInfo, 1);
%pos_z = getword(%transformInfo, 2);
%rot_x = getword(%transformInfo, 3);
%rot_y = getword(%transformInfo, 4);
%rot_z = getword(%transformInfo, 5);

%rot_z = (%rot_z + 0.1) % 1.5;
%shape.setTransform(%pos_x SPC %pos_y SPC %pos_z SPC %rot_x SPC %rot_y SPC %rot_z SPC "1");
schedule(200, 0, rotateShape, %shape);
}

any help at all would be really great. thanks in advance

Torque Owner OneST8
#14
01/17/2007 (8:13 pm)
@Nick: Try this...
$rotateShapeSchedule = 0;
function cancelRotateShape()
{
   if ( $rotateShapeSchedule )
         cancel( $rotateShapeSchedule );
   $rotateShapeSchedule = 0;
}
function rotateShape(%shape)
{
   if ( $rotateShapeSchedule )
         cancel( $rotateShapeSchedule );

   %transformInfo = %shape.getTransform();
   %pos_x = getword(%transformInfo, 0);
   %pos_y = getword(%transformInfo, 1);
   %pos_z = getword(%transformInfo, 2);
   %rot_x = getword(%transformInfo, 3);
   %rot_y = getword(%transformInfo, 4);
   %rot_z = getword(%transformInfo, 5);

   %rot_z = (%rot_z + 0.1) % 1.5;
   %shape.setTransform(%pos_x SPC %pos_y SPC %pos_z SPC %rot_x SPC %rot_y SPC %rot_z SPC "1");
   $rotateShapeSchedule = schedule(200, 0, rotateShape, %shape);
}


(That's untested but should work nearly as-is.)

Torque Owner Bullitt Sesariza
#15
03/03/2008 (8:42 pm)
Hi, I've got a question about scheduling. How do I make an array of global variables that can store the instance of a recursive schedule? E.g I have these schedules that basically do a similar task:

function schedule1()
{
   scheduledTask();
   $sched1 = schedule(1000, 0, schedule1);
}


function schedule2()
{
   scheduledTask();
   $sched2 = schedule(1000, 0, schedule2);
}

function schedule3()
{
   scheduledTask();
   $sched3 = schedule(1000, 0, schedule3);
}

...

function scheduleN()
{
   scheduledTask();
   $schedN = schedule(1000, 0, scheduleN);
}

onMissionLoaded()
{
   $sched1 = schedule(1000, 0, schedule1);
   $sched2 = schedule(1000, 0, schedule2);
   $sched3 = schedule(1000, 0, schedule3);
   ...
   $schedN = schedule(1000, 0, scheduleN); 
}

onMissionEnded()
{
   cancel(   $sched1 );
   cancel(   $sched2 );
   cancel(   $sched3 );
   ...
   cancel(   $schedN );
}

So I was thinking because the array is dynamic and the schedules are actually doing something similar, I thought that I could just use 1 function for the schedule. But what I don't really know is how to store the instances of each schedules so that I can cancel each one of them in onMissionEnded().

Thanks in advance.

EDIT: Nevermind. Got it working by using eval. Thanks though.

Torque Owner DeVry Online Fall Stdnt 08 (#006
#16
12/13/2009 (10:56 am)
Darn trying to do the same thing what is eval?