Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Jay]

Short answer: Generate a new world.  If you really really want to keep your current world, there are a few rules:

Virtually all entity changes whatsoever require a new world. Some don't, and some only do when certain conditions are met. It would be impossible to document every case here.
Adding/removing entire objects requires a new world. NOTICE: Changing an object's identifier does both of these.
All changes to tags except those in entity objects do not require a new world. NOTICE: Some, such as biomes, are highly relevant during worldgen and may not entirely have the desired effect.

Make sure you make your changes in the copy of the raws included in the region's /data/save folder instead of the /raw/objects folder, which is only used during new-world-generation.
If you plan on making a new world, obviously, change the base raws.

Play it safe and generate a new world if you're unsure.

Glossary of terms:
entity -- Refers to an object from any file with a header of [OBJECT:ENTITY]; the same lexicon is true for all other variations of OBJECT:X
tag -- A singular bracketed item that defines a characteristic of an object. Example: [SPEED:900]
object -- An entire collection of tags, preceded by one object tag that makes up virtually anything in the game. Example: [CREATURE:DWARF]
identifier -- In this instance, it refers to the second half of the object tag, which absolutely must be unique to that object, no matter what.

Spoiler: Technical Details (click to show/hide)

Objects are indexed in the region files by their ID; nothing more, nothing less. To add, remove, or rename them, one would have to change this index, which, while possible in uncompressed saves, is probably not a good idea.
Entities? (I really have no idea what goes on internally with them. They're quite the oddball of the DF modding system. If I had to guess, I'd assume that it internally stores the values for each individual civilization when they become relevant, which for a vast majority of them will be worldgen itself.)
Tags, with probable exception to entities as usual, are to my knowledge contained only in the raws as of 0.31. Many are used in worldgen, but still not stored, so the effect of a change may be considerably less than the effect of the same modification with a new world, perhaps even to the extent of having no effect at all. Beware.

UPDATE 7/3/2012: I've experimentally made the line referring to tag changes a flat "all". It may well be wrong, but I haven't seen an exception save what's listed, so...

Let me make it perfectly clear to all who read this. If you find anything that doesn't jive with what I have here, please post in this thread, lest I never hear about it. I can't be everywhere. Also, it's worth noting that I can't test every plausible scenario. I need you to let me know that I'm wrong. (Excepting the entity stuff - I can't maintain that here. I'll link to a Wiki page where people are attempting to do so if such a thing is made, but I simply don't have the time, patience, or especially the space in this post to try.)
Also, I might not be paying the most attention at a given moment. Use this thread to discuss, and if you certifiably prove I need to add something up here, just toss me a PM and I'll wake up and get right on it.

[Vlynndar]

This is good reference. Thanks for putting this in clear view.

[i2amroy]

Don't forget that moving an entire entry from one text document to another will require regen, as the game takes the deleting/adding thing on a text document by text document basis, not on an entire raw basis.

[Footkerchief]

Also, adding/removing/renaming the text files themselves apparently requires deletion of /data/objects.

[Glacies]

Also, adding/removing/renaming the text files themselves apparently requires deletion of /data/objects.

Elaborate on this, please?

[Footkerchief]

Elaborate on this, please?

That was kind of cobbled together from secondhand sources, so I can't elaborate much.  i2amroy could explain in more detail, but people have noticed oddities when they shuffled the raws around, and deleting data/objects seems to fix it.  It's probably another issue with the indexing of various raw entries.

[Untelligent]

In my experience, adding new .txt files doesn't require a deletion of data/objects, only removing or renaming them.

[i2amroy]

Elaborate on this, please?

That was kind of cobbled together from secondhand sources, so I can't elaborate much.  i2amroy could explain in more detail, but people have noticed oddities when they shuffled the raws around, and deleting data/objects seems to fix it.  It's probably another issue with the indexing of various raw entries.

For the renaming of text files, the game creates a cache of each text file based on name. This means that if you change the name of or delete an entire old text file, the game will not erase that cache of the old text file. This in turn means that any entries in that text file will remain in any further world generations, and the only way to solve the problem is to delete that text file's cache in data/objects. For example, if I have a file that is named bob.txt in the raws, than in data/objects there will be a file named bob. The file in data/objects is a cache that contains all data in bob.txt stored so the game can use it. Any changes I make to bob.txt are stored in the bob file which is rewritten every time you start dwarf fortress. However, if I completely remove or rename the bob.txt file, than the bob file is not overwritten, meaning that it retains all of the information of the bob.txt file. So if I had a creature in the bob.txt file, and I delete the bob.txt file, that creature will remain in the world until I deleted the bob file from data/objects. Heck, you could even go right now and delete every text document in the raws file and as long as the data/objects file was untouched your game should still run fine. This only applies to complete removal or renaming of text files, though, if you then create another file that has the same name as one of the old files, then it will overwrite that cache and cause bugs.

[LegoLord]

Actually, moving an entry to another .txt does not require regeneration as long as you cut the entry instead of copying;  I've done it before multiple times, even between releases of the LEGO mod.  I haven't had any problems playing with older forts. 

[Jay]

Adding text files & /data/objects: I've confirmed that you do not need to delete anything, as you're adding a new file, hence it would not have a cache of an old file that you'd have to delete...

Oh yeah, forgot to mention: I've been stickied!

[Assassinfox]

Adding a new Body entry doesn't require a worldgen.

[LegoLord]

Adding a new Body entry doesn't require a worldgen.

That's already there.

[Jay]

Adding a new Body entry doesn't require a worldgen.

That's already there.

You may want to check last edit on my post when you say that...
I believe I added that after that post.

[LegoLord]

Oh, sorry about that.  I think I must have misread it.

[InsanityPrelude]

Messing with reactions requires a regen, doesn't it?