Minimap: Add 'map' mod with mapping kit item to enable minimap

In survival mode, use of the minimap requires the mapping kit item.
Minimap radar mode is always disabled in survival mode.

Minimap and minimap radar mode will be automatically enabled in creative mode
and for any player with the 'creative' privilege.

The 'map.update_hud_flags()' function is global so can be redefined by a mod for
alternative behaviour.

mods/map/init.lua

@@ -0,0 +1,81 @@
+-- Mod global namespace
+
+map = {}
+
+
+-- Cache creative mode setting
+
+local creative_mode_cache = minetest.settings:get_bool("creative_mode")
+
+
+-- Update HUD flags
+-- Global to allow overriding
+
+function map.update_hud_flags(player)
+	local creative_enabled =
+		(creative and creative.is_enabled_for(player:get_player_name())) or
+		creative_mode_cache
+
+	local minimap_enabled = creative_enabled or
+		player:get_inventory():contains_item("main", "map:mapping_kit")
+	local radar_enabled = creative_enabled
+
+	player:hud_set_flags({
+		minimap = minimap_enabled,
+		minimap_radar = radar_enabled
+	})
+end
+
+
+-- Set HUD flags 'on joinplayer'
+
+minetest.register_on_joinplayer(function(player)
+	map.update_hud_flags(player)
+end)
+
+
+-- Cyclic update of HUD flags
+
+local function cyclic_update()
+	for _, player in ipairs(minetest.get_connected_players()) do
+		map.update_hud_flags(player)
+	end
+	minetest.after(7, cyclic_update)
+end
+
+minetest.after(7, cyclic_update)
+
+
+-- Mapping kit item
+
+minetest.register_craftitem("map:mapping_kit", {
+	description = "Mapping Kit",
+	inventory_image = "map_mapping_kit.png",
+	stack_max = 1,
+	groups = {flammable = 3},
+	-- For instant update of HUD flags
+	on_use = function(itemstack, user, pointed_thing)
+		map.update_hud_flags(user)
+	end,
+})
+
+
+-- Crafting
+
+minetest.register_craft({
+	output = "map:mapping_kit",
+	recipe = {
+		{"default:glass", "default:paper", "default:stick"},
+		{"default:steel_ingot", "default:paper", "default:steel_ingot"},
+		{"default:wood", "default:paper", "dye:black"},
+	}
+})
+
+
+-- Fuel
+
+minetest.register_craft({
+	type = "fuel",
+	recipe = "map:mapping_kit",
+	burntime = 5,
+})