Difference between revisions of "LlGetLinkKey"

From Second Life Wiki
Jump to navigation Jump to search
m (clarify description of example - say it is the script that you drag, and link also with LINK_ROOT)
(<lsl> example)
Line 8: Line 8:
|return_text=which is the key of the prim that is link number '''linknum''' in the current link set.
|return_text=which is the key of the prim that is link number '''linknum''' in the current link set.
|spec
|spec
|caveats=*Do provide a nonnegative '''linknum''' between 0 and [[llGetNumberOfPrims]] inclusive, such as [[LINK_ROOT]].
|caveats=*Do provide a non-negative '''linknum''' between 0 and [[llGetNumberOfPrims]] inclusive, such as [[LINK_ROOT]].
* Don't provide [[LINK_THIS]] as the linknum, instead call [[llGetKey]], per bug '''SVC-600'''.  Sorry about that.
* Don't provide [[LINK_THIS]] as the linknum, instead call [[llGetKey]], per bug '''SVC-600'''.  Sorry about that.
* Don't nonsensically provide a linknum that may refer to multiple prims, such as [[LINK_SET]], [[LINK_ALL_OTHERS]], or [[LINK_ALL_CHILDREN]].
* Don't nonsensically provide a linknum that may refer to multiple prims, such as [[LINK_SET]], [[LINK_ALL_OTHERS]], or [[LINK_ALL_CHILDREN]].
|constants
|constants
|examples=
|examples=Drag this script on to linked and unlinked prims, with avatars sitting or not, to see how llGetLinkKey relates to [[llGetKey]], [[llGetLinkNumber]], [[llGetNumberOfPrims]], [[LINK_ROOT]], etc.
Drag this script on to linked and unlinked prims, with avatars sitting or not, to see how llGetLinkKey relates to [[llGetKey]], [[llGetLinkNumber]], [[llGetNumberOfPrims]], [[LINK_ROOT]], etc.
<lsl>// Return the name of a link num else the empty string.
<pre>
// Return the name of a link num else the empty string.


string getLinkNumName(integer link)
string getLinkNumName(integer link)
Line 75: Line 73:
         llOwnerSay("OK");
         llOwnerSay("OK");
     }
     }
}
}</lsl>
</pre>
|helpers
|helpers
|also_functions={{LSL DefineRow||[[llGetKey]]|}}
|also_functions={{LSL DefineRow||[[llGetKey]]|}}

Revision as of 17:19, 2 January 2008

Summary

Function: key llGetLinkKey( integer linknum );
0.0 Forced Delay
10.0 Energy

Returns a key which is the key of the prim that is link number linknum in the current link set.

• integer linknum Link number (0: unlinked, 1: root prim, >1: child prims and seated avatars) or a LINK_* flag
Flag Description
LINK_ROOT 1 refers to the root prim in a multi-prim linked set[1]
LINK_SET -1 refers to all prims
LINK_ALL_OTHERS -2 refers to all other prims
Flag Description
LINK_ALL_CHILDREN -3 refers to all children, (everything but the root)
LINK_THIS -4 refers to the prim the script is in

Caveats

Examples

Drag this script on to linked and unlinked prims, with avatars sitting or not, to see how llGetLinkKey relates to llGetKey, llGetLinkNumber, llGetNumberOfPrims, LINK_ROOT, etc. <lsl>// Return the name of a link num else the empty string.

string getLinkNumName(integer link) {

   if (LINK_THIS == link) return "LINK_THIS";
   if (LINK_ALL_CHILDREN == link) return "LINK_ALL_CHILDREN";
   if (LINK_ALL_OTHERS == link) return "LINK_ALL_OTHERS";
   if (LINK_SET == link) return "LINK_SET";
   if (LINK_ROOT == link) return "LINK_ROOT";
   return "";

}

// Say the key of each linked prim.

default {

   state_entry()
   {
       integer theLink = llGetLinkNumber();
       
       key theLinkKey = llGetKey();
       key owner = llGetOwner();
       key creator = llGetCreator();
       
       // Visit each link num.
       
       integer link;
       integer primmed = llGetNumberOfPrims();
       for (link = -5; link <= (primmed + 5); ++link)
       {
           key linkKey = llGetLinkKey(link);
           
           // Detail the key at the link num.
           
           string line = (string) linkKey; // large constant width
           
           if (linkKey == owner) line += " llGetOwner";
           if (linkKey == creator) line += " llGetCreator";
           if (linkKey == theLinkKey) line += " llGetKey";
           
           // Detail the link num.
           
           line += " @ " + (string) link;
           line += " " + getLinkNumName(link);
           if (link == theLink) line += " llGetLinkNumber";
           if (link == primmed) line += " llGetNumberOfPrims";
           
           // Say the detail if fun.
           
           if (linkKey != NULL_KEY)
           {
               llOwnerSay(line);
           }
       }
       
       // Always count the linked prims.
       
       llOwnerSay((string) primmed + " llGetNumberOfPrims");
       llOwnerSay("OK");
   }
}</lsl>

Notes

Link Numbers

Each prim that makes up an object has an address, a link number. To access a specific prim in the object, the prim's link number must be known. In addition to prims having link numbers, avatars seated upon the object do as well.

  • If an object consists of only one prim, and there are no avatars seated upon it, the (root) prim's link number is zero.
  • However, if the object is made up of multiple prims or there is an avatar seated upon the object, the root prim's link number is one.

When an avatar sits on an object, it is added to the end of the link set and will have the largest link number. In addition to this, while an avatar is seated upon an object, the object is unable to link or unlink prims without unseating all avatars first.

Counting Prims & Avatars

There are two functions of interest when trying to find the number of prims and avatars on an object.

integer GetPrimCount() { //always returns only the number of prims
    if(llGetAttached())//Is it attached?
        return llGetNumberOfPrims();//returns avatars and prims but attachments can't be sat on.
    return llGetObjectPrimCount(llGetKey());//returns only prims but won't work on attachments.
}
See llGetNumberOfPrims for more about counting prims and avatars.

Errata

If a script located in a child prim erroneously attempts to access link 0, it will get or set the property of the linkset's root prim. This bug (BUG-5049) is preserved for broken legacy scripts.

See Also

Functions

•  llGetLinkNumber Returns the link number of the prim the script is in.
•  llGetKey
•  llGetLinkName

Deep Notes

History

Bugs

Footnotes

  1. ^ LINK_ROOT does not work on single prim objects. Unless there is an avatar sitting on the object.

Signature

function key llGetLinkKey( integer linknum );