Difference between revisions of "WarpPos"

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The average time this function takes to execute is under .2 seconds, which is barely noticeable at all, and can easily be attributed to general lag. A simple optimization for an object with a known destination might be to calculate the list beforehand, and then call llSetPrimitiveParams with that list.
The average time this function takes to execute is under .2 seconds, which is barely noticeable at all, and can easily be attributed to general lag. A simple optimization for an object with a known destination might be to calculate the list beforehand, and then call llSetPrimitiveParams with that list.


People interested in this exploit may also find [[posJump]] to be of interest.  A much more efficient method of tricking an object to jump to some arbitrary position.
{{LSLC|Library}}
{{LSLC|Library}}

Revision as of 18:33, 19 September 2008

The corresponding forum thread for this can be found [here].

WarpPos is simply a method by which the 10m limit on non-physical movement can be avoided, by exploiting a glitch in llSetPrimitiveParams in which multiple parameters are executed in a single server frame. <lsl>

warpPos( vector destpos ) 
{   //R&D by Keknehv Psaltery, 05/25/2006
    //with a little pokeing by Strife, and a bit more
    //some more munging by Talarus Luan
    //Final cleanup by Keknehv Psaltery
    //Changed jump value to 411 (4096 ceiling) by Jesse Barnett
    // Compute the number of jumps necessary
    integer jumps = (integer)(llVecDist(destpos, llGetPos()) / 10.0) + 1;
    // Try and avoid stack/heap collisions
    if (jumps > 411)
        jumps = 411;
    list rules = [ PRIM_POSITION, destpos ];  //The start for the rules list
    integer count = 1;
    while ( ( count = count << 1 ) < jumps)
        rules = (rules=[]) + rules + rules;   //should tighten memory use.
    llSetPrimitiveParams( rules + llList2List( rules, (count - jumps) << 1, count) );
    if ( llVecDist( llGetPos(), destpos ) > .001 ) //Failsafe
        while ( --jumps ) 
            llSetPos( destpos );
}

</lsl> A few observations: Sim crossings are perilous for AVs. Depending on connection speed and whether or not you are connected to the sim (can see it on the mini-map), it may screw up your client. However, it seems like objects, by themselves, can cross great distances. I managed to send an object 4 sims away diagonally. Further testing would help us to understand these things.

This comment is outdated: ***The script limits the maximum distance to 1km, in order to prevent stack/heap collisions. Still, this is 100 times what llSetPos was limited to-- and you can, of course, modify it to allow larger distances, but beware.***

Stack/heap is no longer a consideration with MONO. Maximum distance is now set for 4110 meters to account for an updated ceiling height of 4096 meters.

The average time this function takes to execute is under .2 seconds, which is barely noticeable at all, and can easily be attributed to general lag. A simple optimization for an object with a known destination might be to calculate the list beforehand, and then call llSetPrimitiveParams with that list.

People interested in this exploit may also find posJump to be of interest. A much more efficient method of tricking an object to jump to some arbitrary position.