LuaWML/Tiles

This page describes the LuaWML functions for handling terrains and tiles. The items library can be loaded by

items = wesnoth.require "lua/wml/items.lua"

wesnoth.get_map_size

Returns the width, the height, and the border size of the map.

local w,h,b = wesnoth.get_map_size()

wesnoth.get_terrain

Returns the terrain code for the given location.

local is_grassland = wesnoth.get_terrain(12, 15) == "Gg"

wesnoth.set_terrain

Modifies the terrain at the given location.

function create_village(x, y)
    wesnoth.set_terrain(x, y, "Gg^Vh")
end

An optional 4th parameter can be passed (layer): overlay, base or both, default both: Change the specified layer only. An optional 5th boolean parameter (replace_if_failed) can be passed, see the documentation of the [terrain] tag. To pass the 5th parameter but not the 4th, pass nil for the 4th.

wesnoth.get_terrain_info

Returns the terrain details for the given terrain code.

local is_keep = wesnoth.get_terrain_info(wesnoth.get_terrain(12, 15)).keep

Terrain info is a plain table with the following fields:

• id: string
• name, description, editor_name: translatable strings
• castle, keep, village: booleans
• healing: integer

wesnoth.get_selected_tile

Returns the two coordinates of the currently selected tile. This is mostly useful for defining command-mode helpers.

function chg_unit(attr, val)
   local x, y = wesnoth.get_selected_tile()
   if not x then wesnoth.message("Error", "No unit selected."); return end
   helper.modify_unit({ x = x, y = y }, { [attr] = val })
end
-- Function chg_unit can be used in command mode to modify unit attributes on the fly:
--   :lua chg_unit("status.poisoned", true)

wesnoth.get_locations

Returns a table containing all the locations matching the given filter. Locations are stored as pairs: tables of two elements. See StandardLocationFilter for details about location filters.

-- replace all grass terrains by roads
for i,loc in ipairs(wesnoth.get_locations { terrain = "Gg" }) do
    wesnoth.set_terrain(loc[1], loc[2], "Rr")
end

wesnoth.match_location

Returns true if the given location passes the filter.

bool b = wesnoth.match_location(x, y, { terrain = "Ww", { "filter_adjacent_location", terrain = "Ds,*^Bw*" } })

wesnoth.add_tile_overlay

Places a tile overlay (either an image or a halo) at a given location. The overlay is described by a table supporting the same fields as [item]. Note that the overlay is not kept over save/load cycles.

wesnoth.add_tile_overlay(17, 42, { image = "items/orcish-flag.png" })

wesnoth.remove_tile_overlay

Removes all the overlays at the given location. If a filename is passed as a third argument, only this overlay (either image or halo) is removed.

wesnoth.remove_tile_overlay(17, 42, "items/orcish-flag.png")

items.place_image

Places an image at a given location and registers it as a WML [item] would do, so that it can be restored after save/load.

local items = wesnoth.require "lua/wml/items.lua"
items.place_image(17, 42, "items/orcish-flag.png")

items.place_halo

Behaves the same as #items.place_image but for halos.

items.remove

Removes an overlay set by #items.place_image or #items.place_halo. If no filename is provided, all the overlays on a given tile are removed.

items.remove(17, 42, "items/orcish-flag.png")