i3/API.md

API

Custom tabs

i3.new_tab(def)

Custom tabs can be added to the i3 inventory as follow (example):

i3.new_tab {
	name = "stuff",
	description = "Stuff",
	image = "image.png", -- Optional, adds an image next to the tab description

	-- Determine if the tab is visible by a player, `false` or `nil` hide the tab
	access = function(player, data)
		local name = player:get_player_name()
		if name == "singleplayer" then
			return false
		end
	end,

	formspec = function(player, data, fs)
		fs("label[3,1;This is just a test]")
	end,

	fields = function(player, data, fields)
		i3.set_fs(player)
	end,
}

• player is an ObjectRef to the user.
• data are the user data.
• fs is the formspec table which is callable with a metamethod. Each call adds a new entry.
• i3.set_fs(player) must be called to update the formspec.

i3.delete_tab(name)

Deletes a tab by name.

i3.get_tabs()

Returns the list of registered tabs.

---

Custom recipes

Custom recipes are nonconventional crafts outside the main crafting grid. They can be registered in-game dynamically and have a size beyond 3x3 items.

Note: the registration format differs from the default registration format in everything. The width is automatically calculated depending where you place the commas. Look at the examples attentively.

Registering a custom crafting type (example)

i3.register_craft_type("digging", {
	description = "Digging",
	icon = "default_tool_steelpick.png",
})

Registering a custom crafting recipe (examples)

i3.register_craft({
	type   = "digging",
	result = "default:cobble 2",
	items  = {"default:stone"},
})

i3.register_craft({
	result = "default:cobble 16",
	items = {
		"default:stone, default:stone, default:stone",
		"default:stone,              , default:stone",
		"default:stone, default:stone, default:stone",
	}
})

Recipes can be registered in a Minecraft-like way:

i3.register_craft({
	grid = {
		"X  #",
		" ## ",
		"X#X#",
		"X  X",
	},
	key = {
		['#'] = "default:wood",
		['X'] = "default:glass",
	},
	result = "default:mese 3",
})

Multiples recipes can also be registered:

i3.register_craft({
	{
		result = "default:mese",
		items = {
			"default:mese_crystal, default:mese_crystal",
			"default:mese_crystal, default:mese_crystal",
		}
	},

	big = {
		result = "default:mese 4",
		items = {
			"default:mese_crystal, default:mese_crystal",
			"default:mese_crystal, default:mese_crystal",
			"default:mese_crystal, default:mese_crystal",
			"default:mese_crystal, default:mese_crystal",
		}
	},
})

Recipes can be registered from a given URL containing a JSON file (HTTP support is required¹):

i3.register_craft({
	url = "https://raw.githubusercontent.com/minetest-mods/i3/main/test_online_recipe.json"
})

---

Recipe filters

Recipe filters can be used to filter the recipes shown to players. Progressive mode is implemented as a recipe filter.

i3.add_recipe_filter(name, function(recipes, player))

Adds a recipe filter with the given name. The filter function should return the recipes to be displayed, given the available recipes and an ObjectRef to the user. Each recipe is a table of the form returned by minetest.get_craft_recipe.

Example function to hide recipes for items from a mod called "secretstuff":

i3.add_recipe_filter("Hide secretstuff", function(recipes)
	local filtered = {}
	for _, recipe in ipairs(recipes) do
		if recipe.output:sub(1,12) ~= "secretstuff:" then
			filtered[#filtered + 1] = recipe
		end
	end

	return filtered
end)

i3.set_recipe_filter(name, function(recipe, player))

Removes all recipe filters and adds a new one.

i3.remove_recipe_filter(name)

Removes the recipe filter with the given name.

i3.get_recipe_filters()

Returns a map of recipe filters, indexed by name.

---

Search filters

Search filters are used to perform specific searches inside the search field. They can be used like so: <optional name>+<filter name>=<value1>,<value2>,<...>

Examples:

• +groups=cracky,crumbly: search for groups cracky and crumbly in all items.
• sand+groups=falling_node: search for group falling_node for items which contain sand in their names.

Notes:

• If optional name is omitted, the search filter will apply to all items, without pre-filtering.
• Filters can be combined.
• The groups filter is currently implemented by default.

i3.add_search_filter(name, function(item, values))

Adds a search filter with the given name. The search function should return a boolean value (whether the given item should be listed or not).

Example function to show items which contain at least a recipe of given width(s):

i3.add_search_filter("widths", function(item, widths)
	local has_width
	local recipes = recipes_cache[item]

	if recipes then
		for i = 1, #recipes do
			local recipe_width = recipes[i].width
			for j = 1, #widths do
				local width = tonumber(widths[j])
				if width == recipe_width then
					has_width = true
					break
				end
			end
		end
	end

	return has_width
end)

i3.remove_search_filter(name)

Removes the search filter with the given name.

i3.get_search_filters()

Returns a map of search filters, indexed by name.

---

Miscellaneous

i3.group_stereotypes

This is the table indexing the item groups by stereotypes. You can add a stereotype like so:

i3.group_stereotypes.radioactive = "mod:item"

i3.export_url

If set, the mod will export all the cached recipes and usages in a JSON format to the given URL (HTTP support is required¹).

---

¹ Add i3 to the secure.http_mods or secure.trusted_mods setting in minetest.conf.