LSL Protocol/Restrained Love Open Relay Group/sensor

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STATUS: draft

version: 001

A unique command !x-sensor allowing to do remote llSensor()

Description of !x-sensor


The parameters are the same as for the LSL command llSensor(string name, key id, integer type, float range, float arc). The acknowledgment of receipt contains a non empty list of uuid keys, in particular the null key 00000000-0000-0000-0000-000000000000 if nothing is detected, or "ko". No other acknowledgment of receipt is possible.

Two examples with

  • C being the RLV controller which is a grabber (i.e. it already sent a restriction to the relay, accepted by the relay)
  • R being the RLV relay
C-->R  sensor,!x-sensor/name/id/type/range/arc
C<--R  sensor,!x-sensor/name/id/type/range/arc,97116a5b-686b-64a9-a086-cae72a95ce6b,ccb7ce46-eec4-e790-9995-47d789adfe49
C-->R  sensor,!x-sensor/name/id/type/range/arc
C<--R  sensor,!x-sensor/name/id/type/range/arc,00000000-0000-0000-0000-000000000000

The source must be previously accepted by the relay to avoid a bad use of this command; a griefer for example could use it, together with the wildcard, to cause lag in a sim. Even if the command !x-sensor is not a restriction to be saved.

  • C being any RLV source not yet accepted by the relay
  • R being the RLV relay
C-->R  sensor,!x-sensor/name/id/type/range/arc
C<--R  sensor,!x-sensor/name/id/type/range/arc,ko


The effect of this command is that the relay performs a llSensor() with the given parameters, and sends the result as a list of UUID keys separated by a comma to the source in the acknowledgment of receipt using llRegionSayTo().


  • Before sending this kind of command, the source must check by !x-orgversions the presence of 'sensor=' in the acknowledgment of receipt of this command.
  • The maximal possible length of the acknowledgment of receipt is 16*36+15=591<1023. It remains 432 characters for the command !x-sensor/name/id/type/range/arc, more precisely !x-sensor = 9 characters, /////, = 6 characters, id = 36 characters, range = 8 characters maximum, arc = 8 characters (example: 3.141593) maximum, type = 31 characters maximum, so it remains 334 characters for 'name'.
  • !x-sensor enables to use llSensor(), e.g. for a forcesit command or for forcing to follow an object or an avatar or for identifying avatars, when the captured avatar is more than 100m away. It also enables to perform a scan with the relay, not the source, as center.