@ -8,70 +8,132 @@ DFHack modding guide
What is the difference between a script and a mod?
--------------------------------------------------
A script is a single file that can be run as a command in DFHack, like something
that modifies or displays game data on request. A mod is something you install
to get persistent behavioural changes in the game and/or add new content. Mods
can contain and use scripts in addition to (or instead of) modifications to the
DF game raws.
DFHack scripts are written in Lua. If you don't already know Lua, there's a
great primer at `lua.org <https://www.lua.org/pil/contents.html> `__ .
Well, sometimes there is no difference. A mod is anything you add to the game,
which can be graphics overrides, content in the raws, DFHack scripts, any, or
all. There are already resources out there for
`raws modding <https://dwarffortresswiki.org/index.php/Modding> `__ , so this
guide will focus more on scripts, both standalone and as an extension to
raws-based mods.
A DFHack script is a Lua file that can be run as a command in
DFHack. Scripts can do pretty much anything, from displaying information to
enforcing new game mechanics. If you don't already know Lua, there's a great
primer at `lua.org <https://www.lua.org/pil/contents.html> `__ .
Why not just mod the raws?
--------------------------
It depends on what you want to do. Some mods *are* better to do in just the
raws. You don't need DFHack to add a new race or modify attributes, for example.
However, DFHack scripts can do many things that you just can't do in the raws,
like make a creature that trails smoke. Some things *could* be done in the raws,
but writing a script is less hacky, easier to maintain, easier to extend, and is
not prone to side-effects. A great example is adding a syndrome when a reaction
is performed. If done in the raws, you have to create an exploding boulder to
apply the syndrome. DFHack scripts can add the syndrome directly and with much
more flexibility. In the end, complex mods will likely require a mix of raw
modding and DFHack scripting.
raws. You don't need DFHack to add a new race or modify attributes. However,
DFHack scripts can do many things that you just can't do in the raws, like make
a creature that trails smoke or launch a unit into the air when they are hit
with a certain type of projectile. Some things *could* be done in the raws, but
a script is better (e.g. easier to maintain, easier to extend, and/or not prone
to side-effects). A great example is adding a syndrome when a reaction
is performed. If done in the raws, you have to create an exploding boulder as
an intermediary to apply the syndrome. DFHack scripts can add the syndrome
directly and with much more flexibility. In the end, complex mods will likely
require a mix of raw modding and DFHack scripting.
The structure of a mod
----------------------
In the example below, we'll use a mod name of `` example-mod `` . I'm sure your
mods will have more creative names! Mods have a basic structure that looks like
this::
info.txt
graphics/...
objects/...
scripts_modactive/example-mod.lua
scripts_modactive/internal/example-mod/...
scripts_modinstalled/...
README.md (optional)
Let's go through that line by line.
- The :file: `info.txt` file contains metadata about your mod that DF will
display in-game. You can read more about this file in the
`Official DF Modding Guide <https://bay12games.com/dwarves/modding_guide.html> `__ .
- Modifications to the game raws (potentially with custom raw tokens) go in
the :file: `graphics/` and :file: `objects/` folders. You can read more about
the files that go in these directories on the :wiki: `Modding` wiki page.
- A control script in :file: `scripts_modactive/` directory that handles
system-level event hooks (e.g. reloading state when a world is loaded),
registering `overlays <overlay-dev-guide>`
`enabling/disabling <script-enable-api>`
scripts in this directory as well if you want them to appear as runnable
DFHack commands when your mod is active for the current world. Lua modules
that your main scripts use, but which don't need to be directly runnable by
the player, should go in a subdirectory under
:file: `scripts_modactive/internal/` so they don't show up in the DFHack
`launcher <gui/launcher>`
- Scripts that you want to be available before a world is loaded (i.e. on the
DF title screen) or that you want to be runnable in any world, regardless
of whether your mod is active, should go in the
:file: `scripts_modinstalled/` folder. You can also have an :file: `internal/`
subfolder in here for private modules if you like.
- Finally, a :file: `README.md` file that has more information about your mod.
If you develop your mod using version control (recommended!), that
:file: `README.md` file can also serve as your git repository documentation.
These files end up in a subdirectory under :file: `data/installed_mods/` when
the mod is selected as "active" for the first time.
What if I just want to distribute a simple script?
--------------------------------------------------
If your mod is just a script with no raws modifications, things get a bit
simpler. All you need is::
info.txt
scripts_modinstalled/yourscript.lua
README.md (optional)
Adding your script to the :file: `scripts_modinstalled/` folder will allow
DFHack to find it and add your mod to the `script-paths`
runnable from the title screen and in any loaded world, regardless of whether
your mod is explicitly "active".
Be sure to remind players to mark your mod as "active" at least once so it gets
installed to the :file: `data/installed_mods/` folder. They may have to create a
new world just so they can mark the mod as "active". This is true both for
players who copied the mod into the :file: `mods/` folder manually and for
players who subscribed via
`Steam Workshop <https://steamcommunity.com/app/975370/workshop/> `__ .
A mod-maker's development environment
-------------------------------------
While you're writing your mod, you need a place to store your in-development
scripts that will:
- be directly runnable by DFHack
- not get lost when you upgrade DFHack
Create a folder for development somewhere outside your Dwarf Fortress
installation directory (e.g. `` /path/to/mymods/ `` ). If you work on multiple
mods, you might want to make a subdirectory for each mod.
The recommended approach is to create a directory somewhere outside of your DF
installation (let's call it "/path/to/own-scripts") and do all your script
development in there.
If you have changes to the raws, you'll have to copy them into DF's `` data/
installed_mods/`` folder to have them take effect, but you can set things up so
that scripts are run directly from your dev directory. This way, you can edit
your scripts and have the changes available in the game immediately: no
copying, no restarting.
Inside your DF installation folder, there is a file named
:file: `dfhack-config/script-paths.txt` . If you add a line like this to that
file::
How does this magic work? Just add a line like this to your
`` dfhack-config/script-paths.txt `` file::
+/path/to/own-scripts
+/path/to/mymods/example-mod/scripts_modinstalled
Then that directory will be searched when you run DFHack commands from inside
the game. The `` + `` at the front of the path means to search that directory
first, before any other script directory (like :file: `hack/scripts` or
:file: `raw/scripts` ). That way, your latest changes will always be used instead
of older copies that you may have installed in a DF directory.
For scripts with the same name, the `order of precedence <script-paths>`
be:
1. `` own-scripts/ ``
2. `` dfhack-config/scripts/ ``
3. `` save/*/scripts/ ``
4. `` hack/scripts/ ``
first, before any other script directory (like :file: `hack/scripts` or other
versions of your mod in `` data/installed_mods/ `` ).
The structure of the game
-------------------------
"The game" is in the global variable `df <lua-df>`
found in `` df.global `` , containing things like the list of all items, whether to
reindex pathfinding, et cetera. Also relevant to us in `` df `` are the various
types found in the game, e.g. `` df.pronoun_type `` which we will be using in this
guide. We'll explore more of the game structures below.
"The game" is in the global variable `df <lua-df>`
relevant to a script is found in `` df.global.world `` , which contains things
like the list of all items, whether to reindex pathfinding, et cetera. Also
relevant to us are the various data types found in the game, e.g.
`` df.pronoun_type `` which we will be using in this guide. We'll explore more of
the game structures below.
Your first script
-----------------
@ -83,8 +145,8 @@ First line, we get the unit::
local unit = dfhack.gui.getSelectedUnit()
If no unit is selected, an error message will be printed (which can be silenced
by passing `` true `` to `` getSelectedUnit `` ) and `` unit `` will be `` nil `` .
If no unit is selected, `` unit `` will be `` nil `` and
printed (which can be silenced by passing `` true `` to `` getSelectedUnit `` ).
If `` unit `` is `` nil `` , we don't want the script to run anymore::
@ -94,33 +156,32 @@ If ``unit`` is ``nil``, we don't want the script to run anymore::
Now, the field `` sex `` in a unit is an integer, but each integer corresponds to
a string value ("it", "she", or "he"). We get this value by indexing the
bidirectional map `` df.pronoun_type `` . Indexing the other way, incidentally,
with one of the strings, will yield its corresponding number. So::
bidirectional map `` df.pronoun_type `` . Indexing the other way, with one of the
strings, will yield its corresponding number. So::
local pronounTypeString = df.pronoun_type[unit.sex]
print(pronounTypeString)
Simple. Save this as a Lua file in your own scripts directory and run it as
shown before when a unit is selected in the Dwarf Fortress UI.
Simple. Save this as a Lua file in your own scripts directory and run it from
`gui/launcher`
Exploring DF structures
-----------------------
Exploring DF state
------------------
So how could you have known about the field and type we just used? Well, there
are two main tools for discovering the various fields in the game's data
structures. The first is the `` df-structures ``
`repository <https://github.com/DFHack/df-structures> `__ that contains XML files
describing the conten ts of the game's structures. These are complete, but
describing the layou ts of the game's structures. These are complete, but
difficult to read (for a human). The second option is the `gui/gm-editor`
script, an interactive data explorer. You can run the script while objects like
units are selected to view the data within them. You can also run
`` gui/gm-editor scr `` to view the data for the current screen. Press :kbd: `?`
while the script is active to view help.
interface, an interactive data explorer. You can run the script while objects
like units are selected to view the data within them. Press :kbd: `?` while the
script is active to view help.
Familiarising yourself with the many structs of the game will help with ideas
immensely, and you can always ask for help in the `right places <support>`
Detecting trigger s
Reacting to event s
------------------
The common method for injecting new behaviour into the game is to define a
@ -130,7 +191,7 @@ provides two libraries for this, ``repeat-util`` and `eventful <eventful-api>`.
frames (paused or unpaused), ticks (unpaused), in-game days, months, or years.
If you need to be aware the instant something happens, you'll need to run a
check once a tick. Be careful not to do this gratuitously, though, since
running that often can slow down the game!
running callbacks too often can slow down the game!
`` eventful `` , on the other hand, is much more performance-friendly since it will
only call your callback when a relevant event happens, like a reaction or job
@ -327,7 +388,8 @@ Then, let's make a ``repeat-util`` callback for once a tick::
repeatUtil.scheduleEvery(modId, 1, "ticks", function()
Let's iterate over every active unit, and for every unit, iterate over their
worn items to calculate how much we are going to take from their on-foot movement timers::
worn items to calculate how much we are going to take from their on-foot
movement timers::
for _, unit in ipairs(df.global.world.units.active) do
local amount = 0
@ -341,82 +403,78 @@ worn items to calculate how much we are going to take from their on-foot movemen
end
-- Subtract amount from on-foot movement timers if not on ground
if not unit.flags1.on_ground then
dfhack.units.subtractActionTimers(unit, amount, df.unit_action_type_group.MovementFeet)
dfhack.units.subtractActionTimers(unit, amount,
df.unit_action_type_group.MovementFeet)
end
end
The structure of a full mod
---------------------------
For reference, `Tachy Guns <https://www.github.com/wolfboyft/tachy-guns> `__ is a
full mod that conforms to this guide.
Create a folder for mod projects somewhere outside your Dwarf Fortress
installation directory (e.g. `` /path/to/mymods/ `` ) and use your mod IDs as the
names for the mod folders within it. In the example below, we'll use a mod ID of
`` example-mod `` . I'm sure your mods will have more creative names! The
`` example-mod `` mod will be developed in the `` /path/to/mymods/example-mod/ ``
directory and has a basic structure that looks like this::
init.d/example-mod.lua
raw/objects/...
raw/scripts/example-mod.lua
raw/scripts/example-mod/...
README.md
Putting it all together
-----------------------
Let's go through that line by line.
Ok, you're all set up! Now, let's take a look at an example
`` scripts_modinstalled/example-mod.lua `` file::
* A short (one-line) script in `` init.d/ `` to initialise your
mod when a save is loaded.
* Modifications to the game raws (potentially with custom raw tokens) go in
`` raw/objects/ `` .
* A control script in `` scripts/ `` that handles enabling and disabling your
mod.
* A subfolder for your mod under `` scripts/ `` will contain all the internal
scripts and/or modules used by your mod.
-- main file for example-mod
It is a good idea to use a version control system to organize changes to your
mod code. You can create a separate Git repository for each of your mods. The
`` README.md `` file will be your mod help text when people browse to your online
repository.
-- these lines indicate that the script supports the "enable"
-- API so you can start it by running "enable example-mod" and
-- stop it by running "disable example-mod"
--@module = true
--@enable = true
Unless you want to install your `` raw/ `` folder into your DF game folder every
time you make a change to your scripts, you should add your development scripts
directory to your script paths in `` dfhack-config/script-paths.txt `` ::
-- this is the help text that will appear in `help`
-- `gui/launcher`
-- https://docs.dfhack.org/en/latest/docs/Tags.html
--[====[
example-mod
===========
+/path/to/mymods/example-mod/scripts/
Tags: fort | gameplay
Ok, you're all set up! Now, let's take a look at an example
`` scripts/example-mod.lua `` file::
Short one-sentence description ...
-- main setup and teardown for example-mod
-- this next line indicates that the script supports the "enable"
-- API so you can start it by running "enable example-mod" and stop
-- it by running "disable example-mod"
--@ enable = true
Longer description ...
local usage = [[
Usage
-----
enable example-mod
disable example-mod
]]
]====]
local repeatUtil = require('repeat-util')
local eventful = require('plugins.eventful')
-- you can reference global values or functions declared in any of
-- your internal scripts
local moduleA = reqscript('example-mod/module-a')
local moduleB = reqscript('example-mod/module-b')
local moduleC = reqscript('example-mod/module-c')
local moduleD = reqscript('example-mod/module-d')
local moduleA = reqscript('internal/example-mod/module-a')
local moduleB = reqscript('internal/example-mod/module-b')
local moduleC = reqscript('internal/example-mod/module-c')
local moduleD = reqscript('internal/example-mod/module-d')
local GLOBAL_KEY = 'example-mod'
enabled = enabled or false
local modId = 'example-mod'
function isEnabled()
return enabled
end
dfhack.onStateChange[GLOBAL_KEY] = function(sc)
if sc == SC_MAP_UNLOADED then
dfhack.run_command('disable', 'example-mod')
return
end
if sc ~= SC_MAP_LOADED or df.global.gamemode ~= df.game_mode.DWARF then
return
end
dfhack.run_command('enable', 'example-mod')
end
if not dfhack_flags.enable then
print(usage)
print(dfhack.script_help() )
print()
print(('Example mod is currently '):format(
enabled and 'enabled' or 'disabled'))
@ -472,23 +530,17 @@ Ok, you're all set up! Now, let's take a look at an example
enabled = false
end
You can call `` enable example-mod `` and `` disable example-mod `` yourself while
developing, but for end users you can start your mod automatically from
`` init.d/example-mod.lua `` ::
dfhack.run_command('enable example-mod')
Inside `` raw/scripts/example-mod/module-a.lua `` you could have code like this::
Inside `` scripts_modinstalled/internal/example-mod/module-a.lua `` you could
have code like this::
--@ module = true
-- The above line is required for reqscript to work
function onLoad() -- global variables are exported
-- do initialization here
end
-- this is an intern al function: local functions/variables
-- are not exported
-- this is a loc al function: local functions/variables
-- are not accessible to other scripts.
local function usedByOnTick(unit)
-- ...
end
@ -499,6 +551,6 @@ Inside ``raw/scripts/example-mod/module-a.lua`` you could have code like this::
end
end
The `reqscript <reqscript>` can modify
your scripts while DF is running and just disable/enable your mod to load the
changes into your ongoing game!
The `reqscript <reqscript>`
can modify your scripts while DF is running and just disable/enable your mod to
load the changes into your ongoing game!
Myk
GitHub