Difference between revisions of "WarpPos"

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m (updated from llSetPrimitiveParams([___]); to llSetLinkPrimitiveParamsFast(LINK_ROOT, [___]); to make warping faster (no 200 milisecond delay))
m (should be a tiny bit faster...changed from while to do...while)
Line 1: Line 1:
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 )
//  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 410 (4096 ceiling) by Jesse Barnett
//  Compute the number of jumps necessary
 
 
warpPos(vector destinationRootPosition)
{
{
    //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
     vector currentRootPosition = llGetRootPosition();
     vector currentRootPosition = llGetRootPosition();


     integer jumps = (integer)(llVecDist(destinationRootPosition, currentRootPosition) / 10.0) + 1;
     integer jumps = (integer)(llVecDist(destinationRootPosition, currentRootPosition) / 10.0);


     // Try and avoid stack/heap collisions
     // Try and avoid stack/heap collisions
     if (jumps > 411)
     if (jumps > 410)
         jumps = 411;
         jumps = 410;


     // The start for the rules list
     // The start for the rules list
     list rules = [ PRIM_POSITION, destinationRootPosition ];
     list rules = [PRIM_POSITION, destinationRootPosition];


     integer count = 1;
     integer count = 1;
Line 32: Line 33:
     currentRootPosition = llGetRootPosition();
     currentRootPosition = llGetRootPosition();
     if ( llVecDist( currentRootPosition, destinationRootPosition ) > .001 )
     if ( llVecDist( currentRootPosition, destinationRootPosition ) > .001 )
         while ( --jumps )
    {
         do
        {
             llSetLinkPrimitiveParamsFast(LINK_ROOT, [PRIM_POSITION, destinationRootPosition] );
             llSetLinkPrimitiveParamsFast(LINK_ROOT, [PRIM_POSITION, destinationRootPosition] );
        }
        while (--jumps);
    }
}
}
</lsl>
</lsl>

Revision as of 10:51, 25 October 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> // 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 410 (4096 ceiling) by Jesse Barnett // Compute the number of jumps necessary


warpPos(vector destinationRootPosition) {

   vector currentRootPosition = llGetRootPosition();
   integer jumps = (integer)(llVecDist(destinationRootPosition, currentRootPosition) / 10.0);
   // Try and avoid stack/heap collisions
   if (jumps > 410)
       jumps = 410;
   // The start for the rules list
   list rules = [PRIM_POSITION, destinationRootPosition];
   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 )
   {
       do
       {
           llSetLinkPrimitiveParamsFast(LINK_ROOT, [PRIM_POSITION, destinationRootPosition] );
       }
       while (--jumps);
   }

} </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