Luanti Lua Mainmenu API Reference 5.10.0
========================================
Introduction
-------------
The main menu is defined as a formspec by Lua in `builtin/mainmenu/`
Description of formspec language to show your menu is in `lua_api.md`
Images and 3D models
------
Directory delimiters change according to the OS (e.g. on Unix-like systems
is `/`, on Windows is `\`). When putting an image or a 3D model inside a formspec,
be sure to sanitize it first with `core.formspec_escape(img)`; otherwise,
any resource located in a subpath won't be displayed on OSs using `\` as delimiter.
Callbacks
---------
* `core.button_handler(fields)`: called when a button is pressed.
* `fields` = `{name1 = value1, name2 = value2, ...}`
* `core.event_handler(event)`
* `event`: `"MenuQuit"`, `"KeyEnter"`, `"ExitButton"`, `"EditBoxEnter"` or
`"FullscreenChange"`
Gamedata
--------
The "gamedata" table is read when calling `core.start()`. It should contain:
```lua
{
playername = <name>,
password = <password>,
address = <IP/address>,
port = <port>,
selected_world = <index>, -- 0 for client mode
singleplayer = <true/false>,
}
```
Functions
---------
* `core.start()`
* start game session
* `core.close()`
* exit engine
* `core.get_min_supp_proto()`
* returns the minimum supported network protocol version
* `core.get_max_supp_proto()`
* returns the maximum supported network protocol version
* `core.open_url(url)`
* opens the URL in a web browser, returns false on failure.
* `url` must begin with http:// or https://
* `core.open_url_dialog(url)`
* shows a dialog to allow the user to choose whether to open a URL.
* `url` must begin with http:// or https://
* `core.open_dir(path)`
* opens the path in the system file browser/explorer, returns false on failure.
* Must be an existing directory.
* `core.share_file(path)`
* Android only. Shares file using the share popup
* `core.get_version()` (possible in async calls)
* returns current core version
* `core.get_formspec_version()`
* returns maximum supported formspec version
Filesystem
----------
To access specific subpaths, use `DIR_DELIM` as a directory delimiter instead
of manually putting one, as different OSs use different delimiters. E.g.
```lua
"my" .. DIR_DELIM .. "custom" .. DIR_DELIM .. "path" -- and not my/custom/path
```
* `core.get_builtin_path()`
* returns path to builtin root
* `core.create_dir(absolute_path)` (possible in async calls)
* `absolute_path` to directory to create (needs to be absolute)
* returns true/false
* `core.delete_dir(absolute_path)` (possible in async calls)
* `absolute_path` to directory to delete (needs to be absolute)
* returns true/false
* `core.copy_dir(source,destination,keep_source)` (possible in async calls)
* `source` folder
* `destination` folder
* `keep_source` DEFAULT true --> if set to false `source` is deleted after copying
* returns true/false
* `core.is_dir(path)` (possible in async calls)
* returns true if `path` is a valid dir
* `core.extract_zip(zipfile,destination)` [unzip within path required]
* `zipfile` to extract
* `destination` folder to extract to
* returns true/false
* `core.sound_play(spec, looped)` -> handle
* `spec` = `SimpleSoundSpec` (see `lua_api.md`)
* `looped` = bool
* `handle:stop()` or `core.sound_stop(handle)`
* `core.get_video_drivers()`
* get list of video drivers supported by engine (not all modes are guaranteed to work)
* returns list of available video drivers' settings name and 'friendly' display name
e.g. `{ {name="opengl", friendly_name="OpenGL"}, {name="software", friendly_name="Software Renderer"} }`
* first element of returned list is guaranteed to be the NULL driver
* `core.get_mapgen_names([include_hidden=false])` -> table of map generator algorithms
registered in the core (possible in async calls)
* `core.get_cache_path()` -> path of cache
* `core.get_temp_path([param])` (possible in async calls)
* `param`=true: returns path to a newly created temporary file
* otherwise: returns path to a newly created temporary folder
HTTP Requests
-------------
* `core.download_file(url, target)` (possible in async calls)
* `url` to download, and `target` to store to
* returns true/false
* `core.get_http_api()` (possible in async calls)
* returns `HTTPApiTable` containing http functions.
* The returned table contains the functions `fetch_sync`, `fetch_async` and
`fetch_async_get` described below.
* Function only exists if Luanti server was built with cURL support.
* `HTTPApiTable.fetch_sync(HTTPRequest req)`: returns HTTPRequestResult
* Performs given request synchronously
* `HTTPApiTable.fetch_async(HTTPRequest req)`: returns handle
* Performs given request asynchronously and returns handle for
`HTTPApiTable.fetch_async_get`
* `HTTPApiTable.fetch_async_get(handle)`: returns `HTTPRequestResult`
* Return response data for given asynchronous HTTP request
### `HTTPRequest` definition
Used by `HTTPApiTable.fetch` and `HTTPApiTable.fetch_async`.
```lua
{
url = "http://example.org",
timeout = 10,
-- Timeout for connection in seconds. Default is 3 seconds.
post_data = "Raw POST request data string" OR {field1 = "data1", field2 = "data2"},
-- Optional, if specified a POST request with post_data is performed.
-- Accepts both a string and a table. If a table is specified, encodes
-- table as x-www-form-urlencoded key-value pairs.
-- If post_data is not specified, a GET request is performed instead.
user_agent = "ExampleUserAgent",
-- Optional, if specified replaces the default Luanti user agent with
-- given string
extra_headers = { "Accept-Language: en-us", "Accept-Charset: utf-8" },
-- Optional, if specified adds additional headers to the HTTP request.
-- You must make sure that the header strings follow HTTP specification
-- ("Key: Value").
multipart = boolean
-- Optional, if true performs a multipart HTTP request.
-- Default is false.
}
```
### `HTTPRequestResult` definition
Passed to `HTTPApiTable.fetch` callback. Returned by
`HTTPApiTable.fetch_async_get`.
```lua
{
completed = true,
-- If true, the request has finished (either succeeded, failed or timed
-- out)
succeeded = true,
-- If true, the request was successful
timeout = false,
-- If true, the request timed out
code = 200,
-- HTTP status code
data = "response"
}
```
Formspec
--------
* `core.update_formspec(formspec)`
* `core.get_table_index(tablename)` -> index
* can also handle textlists
* `core.formspec_escape(string)` -> string
* escapes characters [ ] \ , ; that cannot be used in formspecs
* `core.explode_table_event(string)` -> table
* returns e.g. `{type="CHG", row=1, column=2}`
* `type`: "INV" (no row selected), "CHG" (selected) or "DCL" (double-click)
* `core.explode_textlist_event(string)` -> table
* returns e.g. `{type="CHG", index=1}`
* `type`: "INV" (no row selected), "CHG" (selected) or "DCL" (double-click)
* `core.set_formspec_prepend(formspec)`
* `formspec`: string to be added to every mainmenu formspec, to be used for theming.
GUI
---
* `core.set_background(type,texturepath,[tile],[minsize])`
* `type`: "background", "overlay", "header" or "footer"
* `tile`: tile the image instead of scaling (background only)
* `minsize`: minimum tile size, images are scaled to at least this size prior
doing tiling (background only)
* `core.set_clouds(<true/false>)`
* `core.set_topleft_text(text)`
* `core.show_keys_menu()`
* `core.show_path_select_dialog(formname, caption, is_file_select)`
* shows a path select dialog
* `formname` is base name of dialog response returned in fields
- if dialog was accepted `"_accepted"`
will be added to fieldname containing the path
- if dialog was canceled `"_cancelled"`
will be added to fieldname value is set to formname itself
* if `is_file_select` is `true`, a file and not a folder will be selected
* returns nil or selected file/folder
* `core.get_active_driver()`:
* technical name of active video driver, e.g. "opengl"
* `core.get_active_renderer()`:
* name of current renderer, e.g. "OpenGL 4.6"
* `core.get_active_irrlicht_device()`:
* name of current irrlicht device, e.g. "SDL"
* `core.get_window_info()`: Same as server-side `get_player_window_information` API.
```lua
-- Note that none of these things are constant, they are likely to change
-- as the player resizes the window and moves it between monitors
--
-- real_gui_scaling and real_hud_scaling can be used instead of DPI.
-- OSes don't necessarily give the physical DPI, as they may allow user configuration.
-- real_*_scaling is just OS DPI / 96 but with another level of user configuration.
{
-- Current size of the in-game render target.
--
-- This is usually the window size, but may be smaller in certain situations,
-- such as side-by-side mode.
size = {
x = 1308,
y = 577,
},
-- Estimated maximum formspec size before Luanti will start shrinking the
-- formspec to fit. For a fullscreen formspec, use this formspec size and
-- `padding[0,0]`. `bgcolor[;true]` is also recommended.
max_formspec_size = {
x = 20,
y = 11.25
},
-- GUI Scaling multiplier
-- Equal to the setting `gui_scaling` multiplied by `dpi / 96`
real_gui_scaling = 1,
-- HUD Scaling multiplier
-- Equal to the setting `hud_scaling` multiplied by `dpi / 96`
real_hud_scaling = 1,
-- Whether the touchscreen controls are enabled.
-- Usually (but not always) `true` on Android.
touch_controls = false,
}
```
Content and Packages
--------------------
Content - an installed mod, modpack, game, or texture pack (txt)
Package - content which is downloadable from the content db, may or may not be installed.
* `core.get_user_path()` (possible in async calls)
* returns path to global user data,
the directory that contains user-provided mods, worlds, games, and texture packs.
* `core.get_modpath()` (possible in async calls)
* returns path to global modpath in the user path, where mods can be installed
* `core.get_modpaths()` (possible in async calls)
* returns table of virtual path to global modpaths, where mods have been installed
The difference with `core.get_modpath` is that no mods should be installed in these
directories by Luanti -- they might be read-only.
Ex:
```lua
{
mods = "/home/user/.minetest/mods",
share = "/usr/share/minetest/mods", -- only provided when RUN_IN_PLACE=0
-- Custom dirs can be specified by the MINETEST_MOD_DIR env variable
["/path/to/custom/dir"] = "/path/to/custom/dir",
}
```
* `core.get_clientmodpath()` (possible in async calls)
* returns path to global client-side modpath
* `core.get_gamepath()` (possible in async calls)
* returns path to global gamepath
* `core.get_texturepath()` (possible in async calls)
* returns path to default textures
* `core.get_games()` -> table of all games (possible in async calls)
* `name` in return value is deprecated, use `title` instead.
* returns a table (ipairs) with values:
```lua
{
id = <id>,
path = <full path to game>,
gamemods_path = <path>,
title = <title of game>,
menuicon_path = <full path to menuicon>,
author = "author",
--DEPRECATED:
addon_mods_paths = {[1] = <path>,},
}
```
* `core.get_content_info(path)`
* returns
```lua
{
name = "technical_id",
type = "mod" or "modpack" or "game" or "txp",
title = "Human readable title",
description = "description",
author = "author",
path = "path/to/content",
textdomain = "textdomain", -- textdomain to translate title / description with
depends = {"mod", "names"}, -- mods only
optional_depends = {"mod", "names"}, -- mods only
}
```
* `core.check_mod_configuration(world_path, mod_paths)`
* Checks whether configuration is valid.
* `world_path`: path to the world
* `mod_paths`: list of enabled mod paths
* returns:
```lua
{
is_consistent = true, -- true is consistent, false otherwise
unsatisfied_mods = {}, -- list of mod specs
satisfied_mods = {}, -- list of mod specs
error_message = "", -- message or nil
}
```
* `core.get_content_translation(path, domain, string)`
* Translates `string` using `domain` in content directory at `path`.
* Textdomains will be found by looking through all locale folders.
* String should contain translation markup from `core.translate(textdomain, ...)`.
* Ex: `core.get_content_translation("mods/mymod", "mymod", core.translate("mymod", "Hello World"))`
will translate "Hello World" into the current user's language
using `mods/mymod/locale/mymod.fr.tr`.
Logging
-------
* `core.debug(line)` (possible in async calls)
* Always printed to `stderr` and logfile (`print()` is redirected here)
* `core.log(line)` (possible in async calls)
* `core.log(loglevel, line)` (possible in async calls)
* `loglevel` one of "error", "action", "info", "verbose"
Settings
--------
* `core.settings:set(name, value)`
* `core.settings:get(name)` -> string or nil (possible in async calls)
* `core.settings:set_bool(name, value)`
* `core.settings:get_bool(name)` -> bool or nil (possible in async calls)
* `core.settings:save()` -> nil, save all settings to config file
For a complete list of methods of the `Settings` object see
[lua_api.md](https://github.com/minetest/minetest/blob/master/doc/lua_api.md)
Worlds
------
* `core.get_worlds()` -> list of worlds (possible in async calls)
* returns
```lua
{
[1] = {
path = <full path to world>,
name = <name of world>,
gameid = <gameid of world>,
},
}
```
* `core.create_world(worldname, gameid, init_settings)`
* `core.delete_world(index)`
Helpers
-------
* `core.get_us_time()`
* returns time with microsecond precision
* `core.gettext(string)` -> string
* look up the translation of a string in the gettext message catalog
* `fgettext_ne(string, ...)`
* call `core.gettext(string)`, replace "$1"..."$9" with the given
extra arguments and return the result
* `fgettext(string, ...)` -> string
* same as `fgettext_ne()`, but calls `core.formspec_escape` before returning result
* `core.parse_json(string[, nullvalue])` -> something (possible in async calls)
* see `core.parse_json` (`lua_api.md`)
* `dump(obj, dumped={})`
* Return object serialized as a string
* `string:split(separator)`
* eg. `string:split("a,b", ",")` == `{"a","b"}`
* `string:trim()`
* eg. `string.trim("\n \t\tfoo bar\t ")` == `"foo bar"`
* `core.is_yes(arg)` (possible in async calls)
* returns whether `arg` can be interpreted as yes
* `core.encode_base64(string)` (possible in async calls)
* Encodes a string in base64.
* `core.decode_base64(string)` (possible in async calls)
* Decodes a string encoded in base64.
* `core.urlencode(str)`: Encodes non-unreserved URI characters by a
percent sign followed by two hex digits. See
[RFC 3986, section 2.3](https://datatracker.ietf.org/doc/html/rfc3986#section-2.3).
Async
-----
* `core.handle_async(async_job,parameters,finished)`
* execute a function asynchronously
* `async_job` is a function receiving one parameter and returning one parameter
* `parameters` parameter table passed to `async_job`
* `finished` function to be called once `async_job` has finished
the result of `async_job` is passed to this function
### Limitations of Async operations
* No access to global lua variables, don't even try
* Limited set of available functions
e.g. No access to functions modifying menu like `core.start`, `core.close`,
`core.show_path_select_dialog`
Background music
----------------
The main menu supports background music.
It looks for a `main_menu` sound in `$USER_PATH/sounds`. The same naming
conventions as for normal sounds apply.
This means the player can add a custom sound.
It will be played in the main menu (gain = 1.0), looped.