Touch start

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Revision as of 03:55, 27 December 2012 by Omei Qunhua (talk | contribs) (Remove obsolete warning. Correct and clarify state change advice)
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Description

Event: touch_start( integer num_detected ){ ; }

Triggered by the start of agent clicking on task

• integer num_detected Number of agents detected touching during the last clockcycle

Caveats

  • If a prim face has Shared Media enabled and the avatar's viewer supports this feature, LSL scripts will not detect touches on that face. Touches from older clients will be detected.
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Examples

You can use numbers 0 through (num_detected-1) with the various llDetected... functions to get detected agent keys etc. For most purposes, it is adequate to bother only with the first detected toucher e.g. llDetectedKey(0). It is rare (but not impossible) for num_detected to be other than 1. <lsl> default {

   touch_start(integer num_detected)
   {
       key    avatarKey  = llDetectedKey(0);
       string avatarName = llDetectedName(0);
       llInstantMessage(avatarKey, "Hello " + avatarName );
   }

} </lsl>

Notes

  • If using a touch to change states be careful about the touch_ event order. The best advice is NOT to do state changes from within touch_start. Add a touch_end event and do the state change there. Changing state from within touch_start can cause the next occurrence of THIS touch_start code to be missed.
  • On clicking a prim with touch events we trigger touch_start (on first contact), touch (during) and touch_end (as released).

Deep Notes

Signature

event void touch_start( integer num_detected );