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sensor

event
Event syntax
sensor(
  1. integer num_detected// Total number of detected targets found (usable with llDetected* functions).
) { … }

The results are ordered from nearest to furthest.

num_detected is always greater than zero, the no_sensor event is triggered if no objects/avatars were found.

Results from a call to either llSensor or llSensorRepeat.

How to use
sensor(integer num_detected)
{
}
  • Lindens in administrative mode cannot be sensed by sensors in the same region as the Linden.
  • Sensors placed in attachments will use the direction the avatar is facing as their forward vector. In mouselook, this means that it will be wherever the avatar is looking, while out of mouselook, this means whichever way the avatar is pointing. This does not include where the avatar’s head is pointing, or what animation the avatar is doing, just the direction the avatar would move in if you walked forward. This is the case, regardless of where the object is attached.
  • A sensor running in an attachment will not detect the avatar wearing it.
  • Only 32 objects will be scanned each time. (Increased from 16 with Release 2024-03-18.8333615376 on Tuesday, March 19, 2024)
  • This event is not executed when nothing is detected, means, you never get the result 0 returned. Use no_sensor for that.
  • on logout all avatars leave a Ghost for a few moments, this results in Failures in llDetected functions in sensor events.
Example 1
6 collapsed lines
default
{
touch_start(integer num_detected)
{
// do a 10m spherical sweep
llSensor("", NULL_KEY, AGENT_BY_LEGACY_NAME, 10.0, PI);
}
sensor (integer num_detected)
{
string message = "Detected " + (string)num_detected + " avatar(s): " + llDetectedName(0);
// we already added the first avatar above, so continue from index 1
integer index = 1;
while (index < num_detected)
message += ", " + llDetectedName(index++);
llWhisper(PUBLIC_CHANNEL, message);
}
no_sensor()
{
llWhisper(PUBLIC_CHANNEL, "Nobody is near me at present.");
}
}
Original wiki source

Some wiki templates and tables need their original context. View this article on the Second Life Wiki. Technical wording and examples are retained from the source; historical guidance may differ from current behavior.

From the Second Life Wiki

Community documentation adapted from Sensor, by Linden Research, Inc. and contributing residents.View contributors and history.

Imported wiki revision:

  • Sensor (revision 1218490, )

Licensed under CC BY-SA 3.0. Last wiki edit: .Formatting and links have been adapted for this site; API metadata follows the LSL definitions.