Merge branch 'moon_phases'

DEVELOPERS.md

@@ -64,6 +64,7 @@ Mods with documented APIs:
 * `rp_localize`: Localize numbers
 * `rp_locks`: Get info about lockable nodes
 * `rp_mobs`: Add mobs (animals, monsters) (EXPERIMENTAL!)
+* `rp_moon`: Get moon phase
 * `rp_music`: Add or remove tracks; start/stop/toggle a music player
 * `rp_paint`: Add paintable nodes; set/remove paint of node
 * `rp_partialblocks`: Register partial blocks (slabs, stairs)

mods/rp_moon/API.md

@@ -0,0 +1,30 @@
+# `rp_moon` API
+
+## How moon phases work
+
+Internally, the moon phase is directly derivied from
+the current game day (`minetest.get_day_count()`) plus
+a random offset that is specific to the world seed.
+
+So on day 0, the moon start with any random phase.
+
+The moon phase is read-only.
+
+## Function reference
+
+### `rp_moon.get_moon_phase()`
+
+Returns current moon phase (0-3).
+
+* 0 = Full Moon
+* 1 = Waning Half Moon
+* 2 = New Moon
+* 3 = Waxing Half Moon
+
+### `rp_moon.update_moon()`
+
+Updates the moon for all players.
+You should call this function after the the time of day
+has been changed in order for the moon phase to be updated
+instantly.
+It is not neccessary to call this function for any other reason.

mods/rp_moon/init.lua

@@ -0,0 +1,90 @@
+-- number of moon phases
+local MOON_PHASES = 4
+-- time in seconds after which to check/update the moon status
+local MOON_UPDATE_TIME = 8.0
+
+-- Randomize initial moon phase, based on map seed
+local mg_seed = minetest.get_mapgen_setting("seed")
+local rand = PseudoRandom(mg_seed)
+local phase_offset = rand:next(0, MOON_PHASES - 1)
+
+minetest.log("info", "[rp_moon] Moon phase offset of this world: "..phase_offset)
+
+rp_moon = {}
+rp_moon.MOON_PHASES = MOON_PHASES
+
+local moon_textures = {
+	[0] = "rp_moon_full_moon.png",
+	[1] = "rp_moon_waning_moon.png",
+	[2] = "rp_moon_new_moon.png",
+	[3] = "rp_moon_waxing_moon.png",
+}
+
+local function get_moon_texture()
+	local phase = rp_moon.get_moon_phase()
+	return moon_textures[phase]
+end
+
+-- Updates the moon for a single player
+local function update_moon_for_player(player)
+	player:set_moon({texture = get_moon_texture()})
+end
+
+-- Updates the moon for all players
+local function update_moon()
+	local moon_arg = {texture = get_moon_texture()}
+	local players = minetest.get_connected_players()
+	for p=1, #players do
+		players[p]:set_moon(moon_arg)
+	end
+end
+
+local timer = 0
+local last_reported_phase = nil
+-- Update the moon for all players after some time has passed
+minetest.register_globalstep(function(dtime)
+	timer = timer + dtime
+	if timer < MOON_UPDATE_TIME then
+		return
+	end
+	timer = 0
+	local phase = rp_moon.get_moon_phase()
+	-- No-op when moon phase didn't change yet
+	if last_reported_phase == phase then
+		return
+	end
+	minetest.log("info", "[rp_moon] New moon phase: "..phase)
+	last_reported_phase = phase
+	update_moon()
+end)
+
+-- Initialize moon for joining player
+minetest.register_on_joinplayer(function(player)
+	update_moon_for_player(player)
+end)
+
+-- Update moon for all players when "time" command was called
+minetest.register_on_chatcommand(function(name, command, params)
+	if command == "time" then
+		minetest.after(0, function()
+			update_moon()
+		end)
+	end
+end)
+
+-- API functions
+
+function rp_moon.get_moon_phase()
+	local after_midday = 0
+	-- Moon phase changes after midday
+	local tod = minetest.get_timeofday()
+	if tod > 0.5 then
+		after_midday = 1
+	end
+	return (minetest.get_day_count() + phase_offset + after_midday) % MOON_PHASES
+end
+
+function rp_moon.update_moon()
+	update_moon()
+end
+

mods/rp_moon/mod.conf

@@ -0,0 +1,2 @@
+name = rp_moon
+description = Moon phases