start working on flags

builtin/mainmenu/dlg_create_world.lua

@@ -90,10 +90,12 @@ local function create_world_formspec(dialogdata)
 		end
 	end
 
-	local lua_mapgens = core.get_lua_mapgen_descriptions_and_title()
+	local lua_mapgens = core.get_lua_mapgens()
+	local is_lua_mapgen = false
 	for k, v in pairs(lua_mapgens) do
 		if not is_internal_mapgen and v.title == dialogdata.mg then
 			current_mapgen = k
+			is_lua_mapgen = true
 		end
 		mapgens[#mapgens+1] = k
 	end
@@ -181,6 +183,11 @@ local function create_world_formspec(dialogdata)
 		end
 	end
 
+	local allowed_lua_mapgen_settings = {}
+	if is_lua_mapgen and lua_mapgens[current_mapgen].mapgen_flags then
+		allowed_lua_mapgen_settings = lua_mapgens[current_mapgen].mapgen_flags
+	end
+
 	-- The logic of the flag element IDs is as follows:
 	-- "flag_main_foo-bar-baz" controls dialogdata.flags["main"]["foo_bar_baz"]
 	-- see the buttonhandler for the implementation of this
@@ -192,6 +199,9 @@ local function create_world_formspec(dialogdata)
 		if disallowed_mapgen_settings["mg_flags"] then
 			return "", y
 		end
+		if is_lua_mapgen and not allowed_lua_mapgen_settings["mg_flags"] then
+			return "", y
+		end
 
 		local form = "checkbox[0," .. y .. ";flag_main_caves;" ..
 			fgettext("Caves") .. ";"..strflag(flags.main, "caves").."]"
@@ -285,7 +295,7 @@ local function create_world_formspec(dialogdata)
 	local str_flags, str_spflags
 	local label_flags, label_spflags = "", ""
 	y = y + 0.3
-	str_flags, y = mg_main_flags(current_mapgen_internal, y)
+	str_flags, y = mg_main_flags(current_mapgen, y)
 	if str_flags ~= "" then
 		label_flags = "label[0,"..y_start..";" .. fgettext("Mapgen flags") .. "]"
 		y_start = y + 0.4
@@ -414,7 +424,7 @@ local function create_world_buttonhandler(this, fields)
 			end
 
 			if not is_internal_mapgen then
-				local lua_mapgens = core.get_lua_mapgen_descriptions_and_title()
+				local lua_mapgens = core.get_lua_mapgens()
 				for name, v in pairs(lua_mapgens) do
 					if v.title == this.data.mg or (v.title == nil and name == this.data.mg) then
 						mapgen_internal = "singlenode"

doc/lua_api.md

@@ -438,7 +438,7 @@ A `Settings` file that provides meta information about the mapgen.
              internal ID used to track versions.
 * `textdomain`: Textdomain used to translate title and description. Defaults to mapgen.
   See [Translating content meta](#translating-content-meta).
-
+* `mapgen_flags`: List of flags to be used
 
 
 Aliases

doc/menu_lua_api.md

@@ -109,7 +109,7 @@ of manually putting one, as different OSs use different delimiters. E.g.
 * `handle:stop()` or `core.sound_stop(handle)`
 * `core.get_mapgen_names([include_hidden=false])` -> table of map generator algorithms
     registered in the core (possible in async calls)
-* `core.get_lua_mapgen_descriptions_and_title()` -> map of `[mapgen_name] = {desc = <mapgen_description>, title = <title>}` as listed
+* `core.get_lua_mapgens()` -> map of `[mapgen_name] = {desc = <mapgen_description>, title = <title>}` as listed
     in `mapgen.conf`, and `nil` if they don't exist.
 * `core.get_cache_path()` -> path of cache
 * `core.get_temp_path([param])` (possible in async calls)

src/content/mods.cpp

@@ -146,6 +146,15 @@ bool parseModContents(ModSpec &spec)
 				}
 			}
 		}
+	} else {
+		if (info.exists("mapgen_flags")) {
+			std::string dep = info.get("mapgen_flags");
+			dep.erase(std::remove_if(dep.begin(), dep.end(),
+					static_cast<int (*)(int)>(&std::isspace)), dep.end());
+			for (const auto &flag : str_split(dep, ',')) {
+				spec.mapgen_flags.insert(flag);
+			}
+		}
 	}
 
 	if (info.exists("description"))

src/content/mods.h

@@ -38,8 +38,9 @@ struct ModSpec
 	bool part_of_modpack = false;
 	bool is_modpack = false;
 
-	// lua-defined mapgen
+	// lua-defined mapgen only
 	bool is_mapgen = false;
+	std::unordered_set<std::string> mapgen_flags;
 
 	/**
 	 * A constructed canonical path to represent this mod's location.

src/script/lua_api/l_mainmenu.cpp

@@ -664,7 +664,7 @@ int ModApiMainMenu::l_get_mapgen_names(lua_State *L)
 }
 
 /******************************************************************************/
-int ModApiMainMenu::l_get_lua_mapgen_descriptions_and_title(lua_State *L)
+int ModApiMainMenu::l_get_lua_mapgens(lua_State *L)
 {
 	std::vector<ModSpec> mapgens_in_path = flattenMods(getModsInPath(porting::path_share + DIR_DELIM + "mapgens" + DIR_DELIM, "mapgen/"));
 
@@ -704,6 +704,20 @@ int ModApiMainMenu::l_get_lua_mapgen_descriptions_and_title(lua_State *L)
 			}
 			lua_settable(L, top_lvl2);
 
+			lua_pushstring(L, "mapgen_flags");
+			if (!mod.mapgen_flags.empty()) {
+				lua_newtable(L);
+				int mapgen_flags_top = lua_gettop(L);
+				for (const auto &flag : mod.mapgen_flags) {
+					lua_pushstring(L, flag.c_str());
+					lua_pushboolean(L, true);
+					lua_settable(L, mapgen_flags_top);
+				}
+			} else {
+				lua_pushnil(L);
+			}
+			lua_settable(L, top_lvl2);
+
 			lua_settable(L, top);
 		}
 	}
@@ -1108,7 +1122,7 @@ void ModApiMainMenu::Initialize(lua_State *L, int top)
 	API_FCT(set_background);
 	API_FCT(set_topleft_text);
 	API_FCT(get_mapgen_names);
-	API_FCT(get_lua_mapgen_descriptions_and_title);
+	API_FCT(get_lua_mapgens);
 	API_FCT(get_user_path);
 	API_FCT(get_modpath);
 	API_FCT(get_modpaths);
@@ -1150,7 +1164,7 @@ void ModApiMainMenu::InitializeAsync(lua_State *L, int top)
 	API_FCT(get_worlds);
 	API_FCT(get_games);
 	API_FCT(get_mapgen_names);
-	API_FCT(get_lua_mapgen_descriptions_and_title);
+	API_FCT(get_lua_mapgens);
 	API_FCT(get_user_path);
 	API_FCT(get_modpath);
 	API_FCT(get_modpaths);

src/script/lua_api/l_mainmenu.h

@@ -51,7 +51,7 @@ private:
 
 	static int l_get_mapgen_names(lua_State *L);
 
-	static int l_get_lua_mapgen_descriptions_and_title(lua_State *L);
+	static int l_get_lua_mapgens(lua_State *L);
 
 	static int l_get_language(lua_State *L);