Add API to control respawn logic and behavior

mods/spawn/api.lua

@@ -0,0 +1,49 @@
+spawn = {}
+
+-- provide empty default implementations
+
+function spawn.get_default_pos()
+	return nil
+end
+
+function spawn.add_suitable_biome(biome)
+end
+
+-- Callback registration
+
+spawn.registered_on_spawn = {}
+
+function spawn.register_on_spawn(func)
+	table.insert(spawn.registered_on_spawn, func)
+end
+
+-- Logic run on spawn
+
+local use_engine_spawn = minetest.settings:get("static_spawnpoint") or
+		minetest.settings:get_bool("engine_spawn")
+
+local function on_spawn(player, is_new)
+	-- Ask all callbacks first
+	for _, cb in ipairs(spawn.registered_on_spawn) do
+		if cb(player, is_new) then
+			return true
+		end
+	end
+	-- Fall back to default spawn
+	if not use_engine_spawn then
+		local pos = spawn.get_default_pos()
+		if pos then
+			player:set_pos(pos)
+			return true
+		end
+	end
+	return false
+end
+
+minetest.register_on_newplayer(function(player)
+	on_spawn(player, true)
+end)
+
+minetest.register_on_respawnplayer(function(player)
+	return on_spawn(player, false)
+end)