When you login, Guild Delta displays changes ("deltas", in math terms) to the guild roster since the last time you logged in. Specifically, names of players who have joined the guild or are no longer in the guild. See below for tracking other kinds of changes.

If you're here about 5.4.2 changes, read Oddities below!

I didn't like being unaware that people had left my (large) guild merely because I happened to not be online at the time they left. And I kept being surprised to find that people I knew had joined the guild when I was offline. So I wrote this simple tool to discover changes in the roster.

Guild Delta only updates its list when you login. After that, it becomes totally inactive and removes as much of itself from memory as it can. This means that even players who join/leave the guild while you are online will be listed the next time you login. This is deliberate.

By default, text is printed to the combat log window so that it won't get lost in the flood of crap that shows up in the main chat window during login. You can use the /guilddelta command to change this, or from the Escape->Interface->AddOns menu.

Starting in release 4, there is basic support for logging all of the deltas for later review. This is disabled by default, use /guilddelta to activate it. The logging is somewhat primitive.

You can dump the guild roster to a text window using the Snapshot button or '/guilddelta output snapshot'. The text is suitable for pasting into a text editor using a fixed-width font. (Line endings are a little weird, that's just how WoW does it and there's nothing I can do about that. Any strings using high-ASCII letters will cause the spacing to be odd; that's also a WoW quirk.)

If you have downloaded this addon from anywhere other than directly from Curse or WoWInterface, then it is outdated at best and infected with viruses at worst. Clone sites not only leech bandwidth, lately they've been adding malware as well. Get your addons from safe sites with a good reputation!

Notes and Oddities

In game version 5.4.2, Blizzard changed the guild roster API to always include the realm name of a player, in order to support connected realms. Unfortunately this means that all your guildmembers will look like they've left, and a brand new roster all joined. It's a one-time flood of noise that they didn't document in patch notes (before, or ever).
If you are promoted to officer rank, any existing officer notes will all be printed out the next time you login, even though they haven't "changed" recently.
Public/officer notes which are erased get no special mention; that is, there is no notification such as PlayerX's note used to be "complete noob spec" but is now empty when logging in.
If GuildDelta reports that a player has left the guild, but Blizzard's builtin Guild Log window makes no mention of the departure, it means that the player has transferred to another faction/realm.
Players who rename their character will be reported as the old player name leaving and the new player name joining.
If you are no longer in a particular guild, you can (and should) clear that guild's information from memory; use the /guilddelta command to see the list of known guilds. If, however, a player is not in any guild at all when logging in, then the addon will not even register itself and in fact unloads itself from memory as much as Blizzard permits. This means that there will not be a /guilddelta command available! Either log on to a character in a guild (any guild), or if you have no characters anywhere in any guild, then... stop loading a guild-related addon. :-)

Localization

If you're a reasonably proficient speaker of non-English languages, any translations you can do would be welcome! Just make changes at http://www.wowace.com/addons/guild-delta/localization/ and then send me a PM to notify me. I can offer nothing in return except public credit, my appreciation, and a beverage of your choice if you're ever in town.