Difference between revisions of "UUID2Channel"

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integer key2Hex(key id) {
integer key2Hex(key id) {
     return -llAbs((integer)("0x" + (string) id));
     return 0x80000000 & (integer)("0x" + (string) id);
}
}
</lsl>
</lsl>

Revision as of 05:13, 4 January 2011

Description

Well, I've figured out a more effective way of using the UUID2Channel method, you know. The one where you put a hexadecimal prefix infront of a person's UUID. Always generates negative integers, for safety.

The Script

<lsl> // Project Neox was here. // Web Gearbox was here too

integer key2Hex(key id) {

   return 0x80000000 & (integer)("0x" + (string) id);

} </lsl>

Suggested Improvement

This generates a unique channel ID from the owner's key (change the llGetOwner() if you wish), but also XOR's it with another value, this value should be application specific.

I encountered an issue where one of the commonly used combat meters (Gorean Meter I think) is using the exact function above to generate its personal channel numbers, and starts complaining - loudly (shouts) - if you put other data on the same channel (user is flooding their own channels!).

As such you shouldn't really use the above function directly for channel IDs, if everyone did, it would negate the entire point of the function, the version below allows you to supply a random constant number to push the allocations around so we're not going to see same-user collisions between applications.

<lsl> // modified channel generator to include per-application key, preventing cross-application collisions // - Iain Maltz

integer generatePersonal(integer ourkey) {

   return -llAbs( ((integer)("0x"+(string)llGetOwner())) ^ ourkey );

} </lsl>

I suggest you sanity check the result, there a 1 in 2 billion or so chance of a zero result.