Difference between revisions of "WarpPos"

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(The last change broke warpPos. Undo revision 1173893 by Kireji Haiku (Talk))
(The last change broke warpPos. Undo revision 1173087 by Kireji Haiku (Talk))
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WarpPos is a method by which the 10m limit on non-physical movement can be avoided, by exploiting a misfeature in [[llSetPrimitiveParams]] in which multiple parameters of the same flag type are executed in a single server frame.
WarpPos is a method by which the 10m limit on non-physical movement can be avoided, by exploiting a misfeature in [[llSetPrimitiveParams]] in which multiple parameters of the same flag type are executed in a single server frame.
<lsl>
<lsl>
warpPos( vector destinationRootPosition )
warpPos( vector destpos )  
{
{   //R&D by Keknehv Psaltery, 05/25/2006
    //R&D by Keknehv Psaltery, 05/25/2006
    //with a little poking by Strife, and a bit more
    //with a little poking by Strife, and a bit more
    //some more munging by Talarus Luan
    //some more munging by Talarus Luan
    //Final cleanup by Keknehv Psaltery
    //Final cleanup by Keknehv Psaltery
    //Changed jump value to 411 (4096 ceiling) by Jesse Barnett
    //Changed jump value to 411 (4096 ceiling) by Jesse Barnett
    // Compute the number of jumps necessary
    // Compute the number of jumps necessary
    integer jumps = (integer)(llVecDist(destpos, llGetPos()) / 10.0) + 1;
 
    // Try and avoid stack/heap collisions
    vector currentRootPosition = llGetRootPosition();
    if (jumps > 411)
 
        jumps = 411;
    integer jumps = (integer)(llVecDist(destinationRootPosition, currentRootPosition) / 10.0) + 1;
    list rules = [ PRIM_POSITION, destpos ];  //The start for the rules list
 
    integer count = 1;
    // Try and avoid stack/heap collisions
    while ( ( count = count << 1 ) < jumps)
    if (jumps > 411)
        rules = (rules=[]) + rules + rules;   //should tighten memory use.
        jumps = 411;
    llSetPrimitiveParams( rules + llList2List( rules, (count - jumps) << 1, count) );
 
    if ( llVecDist( llGetPos(), destpos ) > .001 ) //Failsafe
    // The start for the rules list
        while ( --jumps )  
    list rules = [ PRIM_POSITION, destinationRootPosition ];
            llSetPos( destpos );
 
}
    integer count = 1;
 
    while ( ( count = count << 1 ) < jumps)
        rules = (rules=[]) + rules + rules;// should tighten memory use.
 
    llSetLinkPrimitiveParamsFast(LINK_ROOT,
        rules + llList2List( rules, (count - jumps) << 1, count) );
 
    //Failsafe
    currentRootPosition = llGetRootPosition();
    if ( llVecDist( currentRootPosition, destinationRootPosition ) > .001 )
        while ( --jumps )  
            llSetLinkPrimitiveParamsFast(LINK_ROOT, [PRIM_POSITION, destinationRootPosition] );
}
</lsl>
</lsl>



Revision as of 01:31, 30 November 2012

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

warpPos( vector destpos ) 
{   //R&D by Keknehv Psaltery, 05/25/2006
    //with a little poking 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>

Quote: warpPos -- llSetPos without the limits ~~ Keknehv Psaltery

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.
...
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.
...
a Linden ... response ... go ahead and find a workaround - I'd love to see it, I'm sure it is usefull, but it might not work very well across sim borders