Difference between revisions of "LlGetTime"

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m (Added caveat about gradual resolution loss when representing elapsed time with a float.)
(Unqualify the precision)
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|spec=Script time matches normal time, it is unaffected by time dilation.  For example, if you call llResetTime on two objects in separate simulators at the same time, and later call llGetTime on both at the same time, their values will be equal regardless of differences in dilation.
|spec=Script time matches normal time, it is unaffected by time dilation.  For example, if you call llResetTime on two objects in separate simulators at the same time, and later call llGetTime on both at the same time, their values will be equal regardless of differences in dilation.
|caveats=
|caveats=
*Script time is the amount of real-world time that the script has been in a running state. It is unaffected by time dilation, but it does not count time while the script is suspended, the user is offline (when in an attachment), the object is in inventory rather than rezzed, etc.
*Script time resets when...
*Script time resets when...
**Script reset (user or [[llResetScript]] or [[llResetOtherScript]])
**Script reset (user or [[llResetScript]] or [[llResetOtherScript]])
**Call to either [[llResetTime]] or [[llGetAndResetTime]]
**Call to either [[llResetTime]] or [[llGetAndResetTime]]
*Script time measures real world time, it is unaffected by time dilation.
* Due to (32 bit) floating point number limitations, the accuracy of this function is 1/32sec up to ~3 days, 1/16sec up to ~6 days, etc... doubling each time, e.g. it's only 1 second at ~194 days. Use [[llResetTime]] or [[llGetAndResetTime]] whenever practical to maintain the accuracy you require.
* Due to the way floating point numbers are conceptualised (a 32-bit float), time intervals measured by llGetTime() lose roughly one second of resolution for every six months they represent; thus, after two years llGetTime() can't measure an interval less than four seconds. For very short durations the loss can become significant after only a few days. Use [[llResetTime]] or [[llGetAndResetTime]] whenever practical to maintain reasonable resolution.
|examples=<source lang="lsl2">
|examples=<source lang="lsl2">
default {
default {
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{{LSL DefineRow||[[llGetRegionTimeDilation]]}}
{{LSL DefineRow||[[llGetRegionTimeDilation]]}}
|also
|also
|notes=Script time is the amount of real-world time that the script has been in a running state. It is unaffected by time dilation, but it does not count time while the script is suspended, the user is offline (when in an attachment), the object is in inventory rather than rezzed, etc.
|issues
|issues
|cat1=Time
|cat1=Time

Revision as of 11:51, 11 May 2019

Summary

Function: float llGetTime( );

Returns a float that is script time in seconds with subsecond precision since the script started, was last reset, or call to either llResetTime or llGetAndResetTime.

Specification

Script time matches normal time, it is unaffected by time dilation. For example, if you call llResetTime on two objects in separate simulators at the same time, and later call llGetTime on both at the same time, their values will be equal regardless of differences in dilation.

Caveats

  • Script time is the amount of real-world time that the script has been in a running state. It is unaffected by time dilation, but it does not count time while the script is suspended, the user is offline (when in an attachment), the object is in inventory rather than rezzed, etc.
  • Script time resets when...
  • Due to (32 bit) floating point number limitations, the accuracy of this function is 1/32sec up to ~3 days, 1/16sec up to ~6 days, etc... doubling each time, e.g. it's only 1 second at ~194 days. Use llResetTime or llGetAndResetTime whenever practical to maintain the accuracy you require.
All Issues ~ Search JIRA for related Bugs

Examples

default {
    state_entry()
    {
        llResetTime();
    }
    touch_start(integer num_touch)
    {
        float time = llGetTime(); //Instead getting, and then resetting the time, we could use llGetAndReset() to accomplish the same thing.
        llResetTime();
        llSay(0,(string)time + " seconds have elapsed since the last touch." );
    }
}
// Distinguish between a single click and a double click

float gHoldTime;

default
{
    touch_start(integer total_number)
    {
        float now = llGetTime();
        if (now - gHoldTime < 0.3)
        {
            llSay(PUBLIC_CHANNEL,"Double clicked");
            // Trigger one sequence of actions
        }
        else
        {
            llSetTimerEvent(0.32);
        }
        gHoldTime = now;
    }
    
    timer()
    {
        llSetTimerEvent(0.0);
        if (llGetTime()-gHoldTime > 0.3)
        {
            llSay(PUBLIC_CHANNEL,"Single clicked.");
            // Trigger a different sequence of actions
        }
    }
}
//  To do time-dependant loops of whatever:
//  for example move 2 meters within 5.0 seconds

float time = 5.0;
float i;
llResetTime();
do
{
    i = llGetTime()/time;
    // move2meters*i
}
while (llGetTime() < time);

See Also

Deep Notes

All Issues

~ Search JIRA for related Issues
   llGetTime doesn't reset on admin requested sim restart

Signature

function float llGetTime();