Shared Rare Tracking
 

I'm curious if this idea for a rare tracking addon is possible/plausible.

On the surface, it would behave like NPCScan w/NPCScanOverlay, except instead of using your local machine's cache, it would use an internal database of Rares:

- List out all rare mobs in the game

- Group rares together if they have a shared spawn timer

- When a rare is spotted and either Killed or Tamed by a Hunter, mark the rare as unavailable, remove the overlay blob(s) from the map, and start a timer that, once it counts down the spawn time, makes the mob pop back up on the map as an overlay blob.

- Enable communication (similar to the way the addon Nauticus works) to allow all users of the addon to share their rare-spotted times

- If I use this addon, and another player also uses it, and that player kills a rare on the other side of Azeroth, the overlay blob would disappear off of my map & the timer would start ticking to track when the blob will reappear to show the rare as re-spawned

This would (theoretically) allow you to pull up your map for the area you want to go look for a rare and see (with some accuracy) whether that rare has been killed or spotted recently. If the overlay blob is not showing, it would give you a heads-up that that rare is most likely not there, and you can save the trip to that zone to look for it.

There could also be a LDB plugin that would show a list of rares (maybe sortable by zone/continent) with the estimated time until spawn.

There's nothing technically impossible about your idea, and in theory it would be useful to know I don't need to bother flying halfway across the world to look for a certain rare, but in reality there's a reason there aren't that many addons that rely on addon communication with random players. They can work if you have a large number of people online, in the right places at the right times, and all using the same addon, but otherwise they're so unreliable as to be basically useless, and they're complicated to write, so generally it's just not worth writing them in the first place.

Another point to consider is that while addons of this sort do work for non-competitive stuff, like the Higher Learning books in Dalaran, hunting for rares is extremely competitive. Sure, if you're looking to tame Rare X, you probably don't mind letting everyone know when you see Rare Y nearby -- but if you've got this system set up where everyone tells everyone when they see a rare, then you're only making it harder for yourself to get to Rare X before anyone else. :p

NPCScan and SilverDragon both already use an internal list of rares. The only thing they use your cache for is detecting when one of the models on that list is loaded into the game client's memory, since that generally means the mob using that model now exists somewhere near you in the game world. (That's also why hunter pets trigger NPCScan, because the tamed rare pet still has the same mdoel as the original rare mob, but all the cache can say is "yep, this model is loaded".)

Isn't that obsolete with WoD? I'm almost sure I've read something about "does not longer work with WoD due a changed cacheing-mechanism" somewhere over here.

Also, once you've killed a rare, its no longer rare to you. So you'll only kill it one time.

Cache scanning as we know it today is going away in WoD, yes. However, it will still be possible to detect rares by watching for map vignettes (typically uses the icon that looks like a squashed squirrel skull) etc.

However, OP's proposal has nothing to do with cache scanning, so the loss of it is irrelevant to this topic.

Hmm...I guess a lot has changed since I last played with WoW & addons. I have used NPCScan in the past, and hadn't looked at alternatives (assuming they all worked similarly). Now that you mentioned cache not working the same in the (near) future, I looked at the others & it turns out Silver Dragon has a sync option that you can choose to enable, that seems to do almost exactly what I was inquiring about.

I'm pretty sure that option only syncs with your guild members (and maybe your current group) as is the case with most addons that share data. Unless you're in a large guild with a lot of people who spend a lot of time hanging out around rare spawns, it's not going to do much for you.

Rares in WoD have a respawn timer of about 3 minutes, and while older rares will continue to have longer respawn timers, I think it's unlikely that anyone hunting them would want to broadcast kills to other players because they would be direct competition for your loot.

Also, from a technical standpoint this has major complications caused by CRZ because you can't detect what server you're on. If you're in a cross-realm-zone and you detect a rare die and you broadcast that to your home server, you're providing inaccurate information to the other people running the addon.

Does C_Vignettes.GetVignetteInfoFromInstanceID(id) always return a name now?
Couldn't really test it because of constant server restarts ;)

No idea. I've never worked with the vignette API at all.