Lua on each mapgen thread (#13092)

builtin/emerge/env.lua

@@ -0,0 +1,61 @@
+-- Reimplementations of some environment function on vmanips, since this is
+-- what the emerge environment operates on
+
+-- core.vmanip = <VoxelManip> -- set by C++
+
+function core.set_node(pos, node)
+	return core.vmanip:set_node_at(pos, node)
+end
+
+function core.bulk_set_node(pos_list, node)
+	local vm = core.vmanip
+	local set_node_at = vm.set_node_at
+	for _, pos in ipairs(pos_list) do
+		if not set_node_at(vm, pos, node) then
+			return false
+		end
+	end
+	return true
+end
+
+core.add_node = core.set_node
+
+-- we don't deal with metadata currently
+core.swap_node = core.set_node
+
+function core.remove_node(pos)
+	return core.vmanip:set_node_at(pos, {name="air"})
+end
+
+function core.get_node(pos)
+	return core.vmanip:get_node_at(pos)
+end
+
+function core.get_node_or_nil(pos)
+	local node = core.vmanip:get_node_at(pos)
+	return node.name ~= "ignore" and node
+end
+
+function core.get_perlin(seed, octaves, persist, spread)
+	local params
+	if type(seed) == "table" then
+		params = table.copy(seed)
+	else
+		assert(type(seed) == "number")
+		params = {
+			seed = seed,
+			octaves = octaves,
+			persist = persist,
+			spread = {x=spread, y=spread, z=spread},
+		}
+	end
+	params.seed = core.get_seed(params.seed) -- add mapgen seed
+	return PerlinNoise(params)
+end
+
+
+function core.get_perlin_map(params, size)
+	local params2 = table.copy(params)
+	params2.seed = core.get_seed(params.seed) -- add mapgen seed
+	return PerlinNoiseMap(params2, size)
+end

builtin/emerge/init.lua

@@ -0,0 +1,21 @@
+local gamepath = core.get_builtin_path() .. "game" .. DIR_DELIM
+local commonpath = core.get_builtin_path() .. "common" .. DIR_DELIM
+local epath = core.get_builtin_path() .. "emerge" .. DIR_DELIM
+
+local builtin_shared = {}
+
+-- Import parts shared with "game" environment
+dofile(gamepath .. "constants.lua")
+assert(loadfile(commonpath .. "item_s.lua"))(builtin_shared)
+dofile(gamepath .. "misc_s.lua")
+dofile(gamepath .. "features.lua")
+dofile(gamepath .. "voxelarea.lua")
+
+-- Now for our own stuff
+assert(loadfile(commonpath .. "register.lua"))(builtin_shared)
+assert(loadfile(epath .. "register.lua"))(builtin_shared)
+dofile(epath .. "env.lua")
+
+builtin_shared.cache_content_ids()
+
+core.log("info", "Initialized emerge Lua environment")

builtin/emerge/register.lua

@@ -0,0 +1,54 @@
+local builtin_shared = ...
+
+-- Copy all the registration tables over
+do
+	local all = assert(core.transferred_globals)
+	core.transferred_globals = nil
+
+	all.registered_nodes = {}
+	all.registered_craftitems = {}
+	all.registered_tools = {}
+	for k, v in pairs(all.registered_items) do
+		-- Disable further modification
+		setmetatable(v, {__newindex = {}})
+		-- Reassemble the other tables
+		if v.type == "node" then
+			getmetatable(v).__index = all.nodedef_default
+			all.registered_nodes[k] = v
+		elseif v.type == "craft" then
+			getmetatable(v).__index = all.craftitemdef_default
+			all.registered_craftitems[k] = v
+		elseif v.type == "tool" then
+			getmetatable(v).__index = all.tooldef_default
+			all.registered_tools[k] = v
+		else
+			getmetatable(v).__index = all.noneitemdef_default
+		end
+	end
+
+	for k, v in pairs(all) do
+		core[k] = v
+	end
+end
+
+-- For tables that are indexed by item name:
+-- If table[X] does not exist, default to table[core.registered_aliases[X]]
+local alias_metatable = {
+	__index = function(t, name)
+		return rawget(t, core.registered_aliases[name])
+	end
+}
+setmetatable(core.registered_items, alias_metatable)
+setmetatable(core.registered_nodes, alias_metatable)
+setmetatable(core.registered_craftitems, alias_metatable)
+setmetatable(core.registered_tools, alias_metatable)
+
+--
+-- Callbacks
+--
+
+local make_registration = builtin_shared.make_registration
+
+core.registered_on_mods_loaded, core.register_on_mods_loaded = make_registration()
+core.registered_on_generateds, core.register_on_generated = make_registration()
+core.registered_on_shutdown, core.register_on_shutdown = make_registration()

builtin/game/misc.lua

@@ -237,8 +237,8 @@ end
 core.dynamic_media_callbacks = {}
 
 
--- Transfer of certain globals into async environment
--- see builtin/async/game.lua for the other side
+-- Transfer of certain globals into seconday Lua environments
+-- see builtin/async/game.lua or builtin/emerge/register.lua for the unpacking
 
 local function copy_filtering(t, seen)
 	if type(t) == "userdata" or type(t) == "function" then
@@ -261,6 +261,9 @@ function core.get_globals_to_transfer()
 	local all = {
 		registered_items = copy_filtering(core.registered_items),
 		registered_aliases = core.registered_aliases,
+		registered_biomes = core.registered_biomes,
+		registered_ores = core.registered_ores,
+		registered_decorations = core.registered_decorations,
 
 		nodedef_default = copy_filtering(core.nodedef_default),
 		craftitemdef_default = copy_filtering(core.craftitemdef_default),

builtin/init.lua

@@ -31,8 +31,6 @@ minetest = core
 
 -- Load other files
 local scriptdir = core.get_builtin_path()
-local gamepath = scriptdir .. "game" .. DIR_DELIM
-local clientpath = scriptdir .. "client" .. DIR_DELIM
 local commonpath = scriptdir .. "common" .. DIR_DELIM
 local asyncpath = scriptdir .. "async" .. DIR_DELIM
 
@@ -42,7 +40,7 @@ dofile(commonpath .. "serialize.lua")
 dofile(commonpath .. "misc_helpers.lua")
 
 if INIT == "game" then
-	dofile(gamepath .. "init.lua")
+	dofile(scriptdir .. "game" .. DIR_DELIM .. "init.lua")
 	assert(not core.get_http_api)
 elseif INIT == "mainmenu" then
 	local mm_script = core.settings:get("main_menu_script")
@@ -67,7 +65,9 @@ elseif INIT == "async"  then
 elseif INIT == "async_game" then
 	dofile(asyncpath .. "game.lua")
 elseif INIT == "client" then
-	dofile(clientpath .. "init.lua")
+	dofile(scriptdir .. "client" .. DIR_DELIM .. "init.lua")
+elseif INIT == "emerge" then
+	dofile(scriptdir .. "emerge" .. DIR_DELIM .. "init.lua")
 else
 	error(("Unrecognized builtin initialization type %s!"):format(tostring(INIT)))
 end