code:
Gramophone
==========

A little bit of history...
--------------------------

The _phonograph_ or _gramophone_, is a device for recording and playing sound. It was invented in 1877 by Thomas Edison. The sound vibration waveforms are recorded as corresponding physical deviations of a spiral groove engraved, etched, incised, or impressed into the surface of a rotating cylinder or disc, called a "record". To recreate the sound, the surface is similarly rotated while a playback stylus traces the groove and is therefore vibrated by it, very faintly reproducing the recorded sound. In early acoustic phonographs, the stylus vibrated a diaphragm which produced sound waves which were coupled to the open air through a flaring horn, or directly to the listener's ears through stethoscope-type earphones. [1]

Edison's phonograph used a rotating cylinder to record/play back music. In the 1890s, Emile Berliner introduced the first gramophone or phonograph to use flat discs instead of cylinders.

The Minetest mod
----------------

This Minetest mod is based on Emile Berliner's flat discs (which are, of course, the most popular) and deviates from the usual, classic phonograph style of having an external horn. The design of this gramophone or phonograph is based on devices that don't have an external horn and seems to reproduce from something that resembles a speaker [2]. The decision, of course, is to avoid something that would look entirely out of place in Minetest's cubic design. It also doesn't record music (for now).

This mod is highly inspired by the Jukebox [3] in Minecraft. However, the Minecraft device is too minimalist for my taste, and has lots to explain in terms of crafting recipe and operation. This gramophone mod attempts to be more realistic.

How to use
----------

There are three vital components to make a gramophone work, those are:
- The music player (default is the gramophone),
- One or more speakers,
- One or more music discs (or vinyl records)

Place a gramophone wherever you like (it looks good on top of a speaker node), and then place a speaker node next to the gramophone. It can be at any position as long as it is next to it (top, bottom, left, right, etc.) Then punch the gramophone with a disc in hand, and the disc will be placed on top of it. To make it play, just right-click the gramophone, and the disc will start playing. To stop it, just right-click it again. To take a disc out, just punch the gramophone again and you will have the disc in you inventory again.

A disc shelf is also included. Each shelf has 10 slots for holding 10 different types of music discs.
*Caution*: The shelf, while it really looks nice, it could add to the lag on very low-end computers. This is because it uses entities to show how many discs are in the shelf (reduced to a 2:1 scale).

There are no crafting recipes as-of now. I don't want to add a flimsy crafting recipe for this as I find it very unrealistic. To get one, use `creative` mode or `/giveme` command. I plan to add crafting recipes in the future, where they will actually make sense.

Roadmap
-------
- Add decent crafting recipes
- Add support for finding pieces in dungeons as loot (for MTG 0.5.0 and up)
- Make available 2 or 3 extra music packs (as separate mods to avoid large download size)
- Add more variety of music players?

Licenses
--------
### Code
All code is copyright (C) 2016-2017 Hector Franqui (zorman2000), licensed under the LGPLv2.1 license. See `license.txt` for details.

Some inspiration (and due credit):
- `mcl_jukebox` mod by Wuzzy2 (metadata inventory for disc storage)
- `itemframe` mod by TenPlus1 (disc entity texture persistance)

### Textures
All textures are CC-BY-SA 3.0 by Zorman2000

### Music files

All music files below include the link to the original file. The following modifications has been made to these files (not all apply to all files):

- Changed to mono from stereo
- Tempo was tweaked to fit more my taste.
- Converted from MP3 to OGG

Licenses apply as below.

1. Bagatela nº 25 "Für Elise", WoO 59 (https://musopen.org/es/music/361/ludwig-van-beethoven/bagatelle-no-25-fur-elise-woo-59/)
    - License: CC-PD
    - Composer: Ludwig van Beethoven
    - Performer: Anonymous
2. King Stephen, Op. 117 - I. Overture (https://musopen.org/music/3094/ludwig-van-beethoven/king-stephen-op-117/)
    - License: CC-PD
    - Composer: Ludwig van Beethoven
    - Performer: European Archive
3. Brandenburg Concerto no. 2 in F major, BWV 1047 - I. Allegro (https://musopen.org/music/2726/johann-sebastian-bach/brandenburg-concerto-no-2-in-f-major-bwv-1047/)
    - License: CC-PD
    - Composer: Johann Sebastian Bach
    - Performer: Papalin
4. Brandenburg Concerto no. 2 in F major, BWV 1047 - II. Andante (https://musopen.org/music/2726/johann-sebastian-bach/brandenburg-concerto-no-2-in-f-major-bwv-1047/)
    - License: CC-PD
    - Composer: Johann Sebastian Bach
    - Performer: Papalin
5. Tiento de medio registro de bajo (https://musopen.org/es/music/3135/sebastian-aguilera-de-heredia/tiento-de-medio-registro-de-bajo/)
    - License: CC-BY-SA 3.0
    - Composer: Sebastian Aguilera de Heredia
    - Performer: Rob Peters
6. Concerto No.1 in F major - III. Rondo (https://musopen.org/es/music/1325/wolfgang-amadeus-mozart/piano-concerto-no-1-in-f-k-37/)
    - License: CC-BY-SA 3.0
    - Composer: Wolfgang Amadeus Mozart
    - Performer: Simone Renzi
7. Nocturne in E flat major, Op. 9 no. 2 (https://musopen.org/music/245/frederic-chopin/nocturnes-op-9/)
    - License: CC-PD
    - Composer: Frederic Chopin
    - Performer: Frank Levy
8. Canon and Gigue in D major (Flute quartet arr.) (https://musopen.org/music/2673/johann-pachelbel/canon-and-gigue-in-d-major-flute-quartet-arr/)
    - License: CC-BY-NC
    - Composer: Johann Pachelbel
    - Performer: Steven David Tung
9. String Quartet no. 2 in A major - III. Minuetto scherzo (https://musopen.org/music/3115/juan-crisostomo-de-arriaga/string-quartet-no-2-in-a-major/)
    - License: CC-PD
    - Composer: Juan Crisostomo de Arriaga
    - Performer: European Archive

References
----------
  - [1] https://en.wikipedia.org/wiki/Phonograph
  - [2] https://www.google.com/search?q=amberola+30&client=ubuntu&hs=5Wd&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjf0KXT3YzYAhWDON8KHZtTDREQ_AUICigB&biw=1366&bih=622
  - [3] https://minecraft.gamepedia.com/Jukebox


code:
-- Gramophone and music player API
-- By Zorman2000
-- Some mechanics inspired by mcl_jukebox mod by Wuzzy and itemframe mod by TenPlus1

gramophone = {}

gramophone.temp = {}

gramophone.registered_tracks = {}

-- Use this function register new discs
gramophone.register_disc = function(record_title, artist, color, record_filename)

	-- Enter track into array
	table.insert(gramophone.registered_tracks, {title=record_title, file=record_filename})
	local record_num = #gramophone.registered_tracks

	minetest.register_craftitem("gramophone:vinyl_disc"..record_num, {
		description = "Vinyl Record\n"
			.."Title: "..minetest.colorize(color, record_title).."\n"
			.."Artist: "..artist,
		inventory_image = "vinyl_disc.png^(vinyl_disc_center.png^[colorize:"..color..")",
		groups = {track = record_num, music_disc = 1},
		wield_image = "vinyl_disc.png^(vinyl_disc_center.png^[colorize:"..color..")"
	})
end

gramophone.disc_shelf_formspec =
		"size[8,7]"..
		default.gui_bg..
		default.gui_bg_img..
		default.gui_slots..
		"list[context;main;1.5,0.25;5,2;]"..
		"list[current_player;main;0,2.75;8,1;]"..
		"list[current_player;main;0,4;8,3;8]"..
		"listring[context;main]"..
		"listring[current_player;main]"

gramophone.stop_playback = function(meta, pos)
	local handlers = minetest.deserialize(meta:get_string("gramophone:sound_handler"))
	if handlers then
		for i = 1, #handlers do
			minetest.sound_stop(handlers[i])
		end
		local meta = minetest.get_meta(pos)
		meta:set_string("gramophone:sound_handler", "")
		meta:set_string("gramophone:is_playing", "false")
	end
end

gramophone.on_punch = function(pos, node, clicker, pointed_thing)
	local itemstack = clicker:get_wielded_item()
	-- Check if there is a disc
	local objs = minetest.get_objects_inside_radius(pos, 0.5)
	local disc_obj = nil
	-- Take disc
	if #objs > 0 then
		for _, obj in pairs(objs) do
			if obj and obj:get_luaentity()
			and string.find(obj:get_luaentity().name, "^gramophone:vinyl_disc") then
				disc_obj = obj
				break
			end
		end

		if disc_obj then
			-- Get meta
			local meta = minetest.get_meta(pos)
			--minetest.log("Node: "..dump(node))
			-- Remove disc from gramophone inventory
			local gramophone_inv = meta:get_inventory()
			local disc = gramophone_inv:get_stack("main", 1)
			gramophone_inv:remove_item("main", disc)
			-- Add item to player inventory
			local player_inv = clicker:get_inventory()
			if player_inv:room_for_item("main", disc) then
				if itemstack:get_name() == disc:get_name() then
					itemstack:add_item(disc)
				elseif itemstack:is_empty() then
					--minetest.log("Is empty")
					itemstack:replace(disc)
					--itemstack:set_count(disc:get_count())
				else
					player_inv:add_item("main", disc)
				end
			else
				minetest.add_item(clicker:getpos(), disc:get_name())
			end
			-- Clear values
			disc_obj:remove()
			gramophone.stop_playback(meta, pos)
			meta:set_int("gramophone:current_track", 0)
		end

	else
		-- Check wielded item
		if string.find(itemstack:get_name(), "^gramophone:vinyl_disc") then
			-- Get meta
			local meta = minetest.get_meta(pos)
			-- Add texture data to temporary variable
			gramophone.temp.disc_texture = minetest.registered_items[itemstack:get_name()].inventory_image
			-- Add disc on top of gramophone
			local disc_ent = minetest.add_entity({x=pos.x, y=pos.y - 0.40, z=pos.z}, "gramophone:vinyl_disc")
			-- Remove disk from hand
			local item = itemstack:take_item()
			-- Add item name to meta
			local inv = meta:get_inventory()
			inv:add_item("main", item)
			-- Set track
			minetest.log("Disc track: "..dump(minetest.get_item_group(item:get_name(), "track")))
			meta:set_int("gramophone:current_track", minetest.get_item_group(item:get_name(), "track"))
		end
	end
	--return itemstack
	clicker:set_wielded_item(itemstack)
end

gramophone.on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
	--minetest.log("rightclick")
	local meta = minetest.get_meta(pos)
	local is_playing = meta:get_string("gramophone:is_playing")
	-- Find disc on top of gramophone
	local objs = minetest.get_objects_inside_radius(pos, 0.5)
	if #objs == 0 then
		-- No disc
		--minetest.log("Returning...")
		return itemstack
	end
	if objs then
		for _, obj in pairs(objs) do
			if obj and obj:get_luaentity()
			and obj:get_luaentity().name == "gramophone:vinyl_disc" then
				if is_playing == "true" then
					--minetest.log("This Stopping man...")
					obj:set_properties({automatic_rotate = 0})
				else
					--minetest.log("Playing...")
					obj:set_properties({automatic_rotate = 1})
				end
			end
		end
	end
	-- Start or stop playing
	if is_playing == "true" then
		-- Stop sound
		--minetest.log("Stopping...")
		gramophone.stop_playback(meta, pos)
	else
		-- Start playing sound
		--minetest.log("Playing...")
		local pos1 = vector.subtract(pos, 1)
		local pos2 = vector.add(pos, 1)
		local speakers = minetest.find_nodes_in_area(pos1, pos2, {"gramophone:speaker"})
		minetest.log("Found speakers: "..dump(#speakers))
		-- If speakers found, start playing music on each of them
		if #speakers > 0 then
			local meta = minetest.get_meta(pos)
			meta:set_string("gramophone:is_playing", "true")

			local handlers = {}
			for i = 1, #speakers do
				-- Get track info
				local track_no = meta:get_int("gramophone:current_track") or 0
				minetest.log("Current track no.: "..dump(track_no))
				if track_no > 0 then
					local track_name = gramophone.registered_tracks[track_no].file
					local handler = minetest.sound_play(track_name, {pos = speakers[i], gain = 1.0, max_hear_distance = 32})
					table.insert(handlers, handler)
					meta:set_string("gramophone:sound_handler", minetest.serialize(handlers))
				end
			end
		end
	end
end

gramophone.register_player = function(name, def)
	minetest.register_node("gramophone:"..name, {
	description = def.description,
	tiles = def.tiles,
	drawtype = def.drawtype,
	paramtype = "light",
	paramtype2 = "facedir",
	node_box = def.node_box,
	groups = def.groups,
	on_construct = function(pos)
		local meta = minetest.get_meta(pos)
		meta:set_int("gramophone:current_track", 0)
		meta:set_string("gramophone:is_playing", "false")
		meta:set_string("gramophone:sound_handler", "")
		local inv = meta:get_inventory()
    	inv:set_size("main", 1)
	end,
	on_dig = function(pos, node, digger)
		-- Clear any object disc
		local objs = minetest.get_objects_inside_radius(pos, 0.5)
		for _,obj in pairs(objs) do
			obj:remove()
		end
		-- Pop-up disc if existing
		local meta = minetest.get_meta(pos)
		local disc = meta:get_inventory():get_stack("main", 1)
		if not disc:is_empty() then
			minetest.add_item(pos, disc:get_name())
		end
		-- Remove node
		minetest.remove_node(pos)
	end,
	on_punch = gramophone.on_punch,
	on_rightclick = gramophone.on_rightclick,
})
end

repo_name: korkut/MeseCraft

license: mit


code:
-- Music tracks for Christmas Holiday Pack by FreeGamers.org
-- Depends on the Gramophone mod for Minetest.
-- Gramophone does not allow API to be used from external folders.... :(
-- All songs are public domain.

-- Register the discs.
	-- Deck the Halls
	gramophone.register_disc("Deck the Halls", "Thomas Oliphant", "#165b33", "christmas_record_deck_the_halls")
	-- Jingle Bells
	gramophone.register_disc("Jingle Bells", "James Lord Pierpont", "#146b3a", "christmas_record_jingle_bells")
	-- Silent Night
	gramophone.register_disc("Silent Night", "Joseph Mohr", "#ea4630", "christmas_record_silent_night")
	-- We Wish You A Merry Christmas
	gramophone.register_disc("We Wish You A Merry Christmas", "Arthur Warrell", "#bb2528", "christmas_record_we_wish")


code:
-- Disc registrations
-- Music track licenses can be found on the README.md file
gramophone.register_disc("Für Elise", "Ludwig van Beethoven", "#ffcfac", "default_music_track1_fur_elise")
gramophone.register_disc("King Stephen", "Ludwig van Beethoven", "#abcbff", "default_music_track2_king_stephen")
gramophone.register_disc("Brandenburg Concerto no. 2 - Allegro", "Johann Sebastian Bach", "#acb1ff", "default_music_track3_allegro")
gramophone.register_disc("Brandenburg Concerto no. 2 - Andante", "Johann Sebastian Bach", "#fff9ac", "default_music_track4_andante")
gramophone.register_disc("Tiento de medio registro de bajo", "Sebastian Aguilera de Heredia", "#acffcf", "default_music_track5_tiento")
gramophone.register_disc("Concerto No. 1 - Rondo", "Wolfgang Amadeus Mozart", "#dac744", "default_music_track6_rondo")
gramophone.register_disc("Nocturne Op. 9 no. 2", "Frederic Chopin", "#86dd2a", "default_music_track7_nocturne")
gramophone.register_disc("Canon and Gigue in D Major", "Johann Pachelbel", "#cb3f1b", "default_music_track8_canon")
gramophone.register_disc("String Quartet no. 2 - Minuetto ", "Juan Crisostomo de Arriaga", "#520559", "default_music_track9_minuetto")


code:
-- Gramophone mod by Zorman2000
-- Compatible with Minetest 0.4.14 and later
--
-- Similar to a Minecraft jukebox, but better :)
-- Includes API for registering music discs and music players.
-- Also, includes a disc shelf (caution: not lightweight in any sense!)

local path = minetest.get_modpath("gramophone")

dofile(path .. "/api.lua")
dofile(path .. "/nodes.lua")
dofile(path .. "/shelf.lua")
dofile(path .. "/default_music.lua")
dofile(path .. "/christmas_music.lua")


code:
name = gramophone
depends = default


code:
-- Node registration

-- Register default gramophone (music player)
gramophone.register_player("gramophone", {
	description = "Gramophone",
	tiles = {
		"gramophone_inside2.png", "speaker_side.png",
		"gramophone_side3.png", "gramophone_side4.png",
		"gramophone_front.png", "gramophone_front.png"
	},
	drawtype = "nodebox",
	node_box = {
		type = "fixed",
		fixed = {
			{-0.5, -0.5, -0.5, 0.5, -0.375, -0.4375}, -- NodeBox1
			{-0.5, -0.5, -0.5, -0.4375, -0.375, 0.5}, -- NodeBox2
			{0.4375, -0.5, -0.5, 0.5, -0.375, 0.5}, -- NodeBox3
			{-0.5, -0.5, 0.4375, 0.5, -0.375, 0.5}, -- NodeBox4
			{-0.4375, -0.5, -0.4375, 0.4375, -0.4375, 0.4375}, -- NodeBox5
			{-0.0625, -0.5, 0.3125, 0.0625, -0.375, 0.4375}, -- NodeBox6
			{-0.125, -0.375, 0.1875, 0.125, -0.25, 0.4375}, -- NodeBox7
		}
	},
	groups = {cracky = 2}
})

-- Speaker node
minetest.register_node("gramophone:speaker", {
	description = "Speaker",
	tiles = {
		"speaker_top.png", "speaker_side.png",
		"speaker_side.png", "speaker_side.png",
		"speaker_side.png", "speaker_front.png"
	},
	paramtype = "light",
	paramtype2 = "facedir",
	groups = {cracky = 2}
})

-- Entity disc when placed on gramophone
minetest.register_entity("gramophone:vinyl_disc", {
	hp_max = 1,
	visual = "cube",
	--mesh = "vinyl_disc.obj",
	visual_size={x = 1, y = 0, z = 1},
	collisionbox = {0, 0, 0, 0, 0, 0},
	physical = false,
	textures = {"vinyl_disc.png", "air", "air", "air", "air", "air"},
	on_activate = function(self, staticdata)
		minetest.log("static data: "..dump(staticdata))
		if gramophone.temp.disc_texture ~= nil then
			-- Set texture from temp
			self.disc_texture = gramophone.temp.disc_texture
			gramophone.temp.disc_texture = nil
		elseif staticdata ~= nil and staticdata ~= "" then
			-- Set texture from static data
			local data = staticdata
			if data then
				self.disc_texture = data
			end
		end
		-- Set texture if available
		if self.disc_texture ~= nil then
			self.textures = {self.disc_texture, "air", "air", "air", "air", "air"}
			self.object:set_properties(self)
		end
	end,
	get_staticdata = function(self)
		if self.disc_texture ~= nil then
			return self.disc_texture
		end
		return ""
	end,
})

-- Entity for shelf
minetest.register_entity("gramophone:vinyl_disc_vertical", {
	hp_max = 1,
	visual = "wielditem",
	visual_size = {x = 0.45, y = 0.45, z = 0.0625},
	collisionbox = {0,0,0, 0,0,0},
	physical = false,
	textures = {"vinyl_disc.png"},
	wield_item = "gramophone:vinyl_disc1"
})

--Crafts
--gramophone:speaker
minetest.register_craft({
	output = "gramophone:speaker",
	recipe = {
		{"default:wood", "default:wood", "default:wood"},
		{"default:wood", "default:copperblock", "default:wood"},
		{"default:wood", "default:wood", "default:wood"}
	}
})
--gramophone:gramophone
minetest.register_craft({
        output = "gramophone:gramophone",
        recipe = {
                {"default:wood", "default:obsidian_shard", "default:wood"},
                {"default:stone", "default:wood", "default:stone"},
                {"default:wood", "default:wood", "default:wood"}
        }
})
--gramophone:vinyl_disc[1..9] have just mobs drop them.


code:
-- Disc shelf for storing music discs
-- Inventory overlay and blast code taken from vessels mod in MTG
-- All other code by Zorman2000

local function get_disc_shelf_formspec(inv)
	local formspec = gramophone.disc_shelf_formspec
	local invlist = inv and inv:get_list("main")
	-- Inventory slots overlay
	local vx, vy = 1.5, 0.25
	for i = 1, 10 do
		if i == 6 then
			vx = 1.5
			vy = vy + 1
		end
		if not invlist or invlist[i]:is_empty() then
			formspec = formspec ..
				"image[" .. vx .. "," .. vy .. ";1,1;vinyl_disc_overlay.png]"
		end
		vx = vx + 1
	end
	return formspec
end

local function update_disc_shelf(pos)
	-- Remove all objects
	local objs = minetest.get_objects_inside_radius(pos, 0.5)
	for _,obj in pairs(objs) do
		obj:remove()
	end

	local node = minetest.get_node(pos)
	local node_dir = minetest.facedir_to_dir(node.param2)
	local disc_dir = minetest.facedir_to_dir(node.param2 + 1 % 3)
	-- Place entities
	local start_pos = {
		x=pos.x - (0.585 * disc_dir.x) - (node_dir.x * 0.185),
		y=pos.y - 0.15,
		z=pos.z - (0.585 * disc_dir.z) - (node_dir.z * 0.185)}
	-- Calculate max disc count out of the 10 discs placeable in the shelf
	local inv = minetest.get_meta(pos):get_inventory()
	local list = inv:get_list("main")
	local max_disc_count = 0
	for _,itemstack in pairs(list) do
		if not itemstack:is_empty() then
			max_disc_count = max_disc_count + 1
		end
	end
	-- Update inventory images
	minetest.get_meta(pos):set_string("formspec", get_disc_shelf_formspec(inv))
	minetest.log("Found "..dump(max_disc_count).." disc stacks on inventory")
	if max_disc_count > 0 then
		if max_disc_count == 1 then
			max_disc_count = 2
		end
		minetest.log("Adding "..dump(math.floor(max_disc_count / 2)).." disc entities")
		-- Correct z
		if disc_dir.z == 0 and disc_dir.x == 0 then
			disc_dir.z = 1
		end
		for i = 1, math.floor(max_disc_count / 2) do
			minetest.log("I: "..dump(i))
			minetest.log("Start pos.x: "..dump(start_pos.x)..", disc_dir.x: "..dump(disc_dir.x)..", i: "..dump(i))
			minetest.log("Start pos.z: "..dump(start_pos.z)..", disc_dir.z: "..dump(disc_dir.z)..", i: "..dump(i))

			local disc_pos = {
					x=start_pos.x + (0.195 * i * disc_dir.x),
					y=start_pos.y,
					z=start_pos.z + (0.195 * i * disc_dir.z)
				}
			minetest.log("Adding disc entity at "..minetest.pos_to_string(disc_pos))
			local ent = minetest.add_entity(disc_pos,"gramophone:vinyl_disc_vertical")
			ent:set_yaw(minetest.dir_to_yaw(minetest.facedir_to_dir(node.param2 + 1 % 3)))
		end
	end

end

-- Disc shelf
minetest.register_node("gramophone:disc_shelf", {
	description = "Vinyl Record Shelf",
	tiles = {
		"speaker_side.png", "speaker_side.png",
		"speaker_side.png", "speaker_side.png",
		"speaker_side.png", "vinyl_disc_shelf_front.png",
	},
	paramtype = "light",
	paramtype2 = "facedir",
	drawtype = "nodebox",
	node_box = {
		type = "fixed",
		fixed = {
			{-0.5, -0.5, -0.5, -0.4375, 0.5, 0.5}, -- NodeBox1
			{0.4375, -0.5, -0.5, 0.5, 0.5, 0.5}, -- NodeBox2
			{-0.5, 0.4375, -0.5, 0.5, 0.5, 0.5}, -- NodeBox3
			{-0.5, -0.5, -0.5, 0.5, -0.4375, 0.5}, -- NodeBox4
			{-0.5, -0.5, 0.4375, 0.5, 0.5, 0.5}, -- NodeBox5
			{-0.3125, -0.5, -0.4375, -0.25, 0.1875, 0.5}, -- NodeBox6
			{-0.125, -0.5, -0.4375, -0.0625, 0.1875, 0.5}, -- NodeBox7
			{0.0625, -0.5, -0.4375, 0.125, 0.1875, 0.5}, -- NodeBox8
			{0.25, -0.5, -0.4375, 0.3125, 0.1875, 0.5}, -- NodeBox9
		}
	},
	groups = {cracky = 2},
	on_construct = function(pos)
		-- Initialize inventory
		local meta = minetest.get_meta(pos)
		local inv = meta:get_inventory()
    	inv:set_size("main", 10)
    	-- Initialize formspec
    	meta:set_string("formspec", get_disc_shelf_formspec(inv))
	end,
	allow_metadata_inventory_put = function(pos, listname, index, stack, player)
		if minetest.get_item_group(stack:get_name(), "music_disc") ~= 0 then
			return stack:get_count()
		end
		return 0
	end,
	on_metadata_inventory_put = update_disc_shelf,
	on_metadata_inventory_take = update_disc_shelf,
	on_dig = function(pos, node, digger)
		-- Clear any object disc
		local objs = minetest.get_objects_inside_radius(pos, 0.5)
		for _,obj in pairs(objs) do
			obj:remove()
		end
		-- Pop-up disc if existing
		local meta = minetest.get_meta(pos)
		local list = meta:get_inventory():get_list("main")
		for _,item in pairs(list) do
			local drop_pos = {
				x=math.random(pos.x - 0.5, pos.x + 0.5),
				y=pos.y,
				z=math.random(pos.z - 0.5, pos.z + 0.5)}
			minetest.add_item(pos, item:get_name())
		end
		-- Remove node
		minetest.remove_node(pos)
	end,
	on_blast = function(pos)
		local drops = {}
		default.get_inventory_drops(pos, "vessels", drops)
		drops[#drops + 1] = "gramophone:disc_shelf"
		minetest.remove_node(pos)
		return drops
	end
})
--gramophone:disc_shelf
minetest.register_craft({
	output = "gramophone:disc_shelf",
	recipe = {
		{"default:wood", "default:wood", "default:wood"},
		{"default:wood", "gramophone:gramophone", "default:wood"},
		{"default:wood", "default:wood", "default:wood"}
	}
})


code:
GNU GENERAL PUBLIC LICENSE
Version 3, 29 June 2007

Copyright © 2007 Free Software Foundation, Inc. <https://fsf.org/>

Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

Preamble
The GNU General Public License is a free, copyleft license for software and other kinds of works.

The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program--to make sure it remains free software for all its users. We, the Free Software Foundation, use the GNU General Public License for most of our software; it applies also to any other work released this way by its authors. You can apply it to your programs, too.

When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for them if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things.

To protect your rights, we need to prevent others from denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the software, or if you modify it: responsibilities to respect the freedom of others.

For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.

Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy, distribute and/or modify it.

For the developers' and authors' protection, the GPL clearly explains that there is no warranty for this free software. For both users' and authors' sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions.

Some devices are designed to deny users access to install or run modified versions of the software inside them, although the manufacturer can do so. This is fundamentally incompatible with the aim of protecting users' freedom to change the software. The systematic pattern of such abuse occurs in the area of products for individuals to use, which is precisely where it is most unacceptable. Therefore, we have designed this version of the GPL to prohibit the practice for those products. If such problems arise substantially in other domains, we stand ready to extend this provision to those domains in future versions of the GPL, as needed to protect the freedom of users.

Finally, every program is threatened constantly by software patents. States should not allow patents to restrict development and use of software on general-purpose computers, but in those that do, we wish to avoid the special danger that patents applied to a free program could make it effectively proprietary. To prevent this, the GPL assures that patents cannot be used to render the program non-free.

The precise terms and conditions for copying, distribution and modification follow.

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a) The work must carry prominent notices stating that you modified it, and giving a relevant date.
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IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

17. Interpretation of Sections 15 and 16.
If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee.

END OF TERMS AND CONDITIONS


code:
                  GNU LESSER GENERAL PUBLIC LICENSE
                       Version 2.1, February 1999

 Copyright (C) 1991, 1999 Free Software Foundation, Inc.
 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

[This is the first released version of the Lesser GPL.  It also counts
 as the successor of the GNU Library Public License, version 2, hence
 the version number 2.1.]

                            Preamble

  The licenses for most software are designed to take away your
freedom to share and change it.  By contrast, the GNU General Public
Licenses are intended to guarantee your freedom to share and change
free software--to make sure the software is free for all its users.

  This license, the Lesser General Public License, applies to some
specially designated software packages--typically libraries--of the
Free Software Foundation and other authors who decide to use it.  You
can use it too, but we suggest you first think carefully about whether
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That's all there is to it!


code:
-- Hangglider mod for Minetest
-- Original code by Piezo_ (orderofthefourthwall@gmail.com)
-- 2018-11-14

-- Modifications by David G (kestral246@gmail.com)
-- 2018-11-24
-- For Minetest 5.x, glider's set_attach needs to be offset by 1 node
--     Switch to alternate commented line below with correct offset.
-- Additional tuning of parameters.
-- Commented out debug hud display code, prefixed with "--debug:".

-- 2018-11-22
-- Give visual indication that hangglider is equiped.
--     Display simple overlay with blurred struts when equiped.
--     Issue: don't know how to disable overlay in third person view.
-- Also Unequip hangglider when landing on water.
-- Attempt to linearize parabolic flight path.
--     Start gravity stronger, but gradually reduce it as descent velocity increases.
--     Don't use airstopper when equipped from the ground (descent velocity is low).
--     Slightly increase flight speed to 1.25.
-- Unequip/equip cycling mid-flight should not fly farther than continuous flight.
--     When equipping mid-air (descent velocity higher), use airstopper but increase descent slope afterwards.
--     Create airbreak flag so all equips mid-flight use faster descent.
--     Reset airbreak flag only when land (canExist goes false).
--     Issue: it wouldn't reset if land in water, use fly, and launch from air, before I added test for water,
--            not sure if there are other such cases.
-- Temporarily add hud debug display to show descent velocity, gravity override, and airbreak flag.
--     Still in process of tuning all the parameters.

-- Modifications by Piezo_
-- 2018-11-25
-- hud overlay and debug can be enabled/disabled
-- Added blender-rendered overlay for struts using the actual model.
-- Reduced airbreak penalty severity
-- gave glider limited durability.
-- Improved gravity adjustment function.
-- Changed airbreaking process
-- Removed airbreak penalty, as any 'advantage' seems minimal after new adjustments
-- Removed airbreak until minetest devs are smart enough to implement better serverside players.
-- Simplified liquid check.

-- Modifications by gpcf
-- 2018-12-09
-- get shot down while flying over protected areas marked as no-fly-zones (flak, from German Flugabwehrkanone)
--  set these areas with the /area_flak command

-- Modifications by SpaghettiToastBook
-- 2018-12-29
-- Physics overrides use player_monoids mod if available

local HUD_Overlay = true --show glider struts as overlay on HUD
local debug = false --show debug info in top-center of hud
local moveModelUp = false
if tonumber(string.sub(minetest.get_version().string, 1, 1)) and tonumber(string.sub(minetest.get_version().string, 1, 1)) > 4 then
	moveModelUp = true
end
hangglider = {} --Make this global, so other mods can tell if hangglider exists.
hangglider.use = {}
if HUD_Overlay then
hangglider.id = {}  -- hud id for displaying overlay with struts
end
if debug then  hangglider.debug = {} end -- hud id for debug data
--hangglider.airbreak = {}  -- true if falling fast when equip
--[[
minetest.register_entity("hangglider:airstopper", { --A one-instant entity that catches the player and stops them.
	is_visible = false,
	physical = false,
	immortal = true,
	attach = nil,
	on_step = function(self, _)
		local canExist = false
		if self.attach then
			local player = self.attach
			if player:is_player() then
				local pname = player:get_player_name()
				canExist = true
				if player:get_player_velocity().y < 0.5 and player:get_player_velocity().y > -0.5 then
					--Let go when the player actually stops, as that's the whole point.
					if hangglider.use[pname] then
						if moveModelUp then
							minetest.add_entity(player:get_pos(), "hangglider:glider"):set_attach(player, "", {x=0,y=10,z=0}, {x=0,y=0,z=0})
						else
							minetest.add_entity(player:get_pos(), "hangglider:glider"):set_attach(player, "", {x=0,y=0,z=0}, {x=0,y=0,z=0})
						end
					end
					canExist = false
				end
			end
			if not canExist then
				player:set_detach()
			end
		end
		if not canExist then
			self.object:remove()
		end
	end
})]]

if core.global_exists("areas") then
	hangglider.flak = true
	-- chat command definition essentially copied from areas mod.
	minetest.register_chatcommand("area_flak",{
		params = "<ID>",
		description = "Toggle airspace restrictions for area <ID>",
		func = function(name, param)
			local id = tonumber(param)
			if not id then
				return false, "Invalid usage, see /help area_flak."
			end

			if not areas:isAreaOwner(id, name) then
				return false, "Area "..id.." does not exist"
					.." or is not owned by you."
			end
			local open = not areas.areas[id].flak
			-- Save false as nil to avoid inflating the DB.
			areas.areas[id].flak = open or nil
			areas:save()
			return true, ("Area's airspace %s."):format(open and "closed" or "opened")
		end
	})
end

if core.global_exists("minetestd") and minetestd.services.physicsctl.enabled then
minetestd.physicsctl.register_physics_effect("hangglider",
	function(player) -- check
		return hangglider.use[player:get_player_name()]
	end,
	function(phys, player) -- blend
		local vel_y = player:get_player_velocity().y
		if debug then player:hud_change(hangglider.debug[pname].id, "text", vel_y..', '..player:get_physics_override().gravity..', '..tostring(hangglider.airbreak[pname])) end
		phys.gravity = phys.gravity*((vel_y + 3)/20)
		if vel_y < 0 and vel_y > -3 then
			phys.speed = (math.abs(vel_y/2) + 0.75)
		elseif vel_y <= -3 then --Cap our gliding movement speed.
			phys.speed = 2.25
		end
		phys.jump = 0
	end,
	7 -- effect order
)
end

hangglider.can_fly = function (pname, pos)
	-- Checks if the player will get shot down at the position
	if wardzones then
		local zone = wardzones.getZone(pos)
		if zone then
			return (minetest.check_player_privs(pname, {protection_bypass=true}) or wardzones.checkPlayerZoneAccess(pname, zone) or not zone["data"]["no_fly"])
		end
	end
	if areas and minetest.is_protected(vector.round(pos), pname) then
		if hangglider.flak then
			for id, area in pairs(areas:getAreasAtPos(pos)) do
				if area.flak then
					return false
				end
			end
		end
	end
	return true
end

hangglider.shot_sound = function (pos)
	minetest.sound_play("hangglider_flak_shot", {
		pos = pos,
		max_hear_distance = 30,
		gain = 10.0,
	})
end

local physics_attrs = {"jump", "speed", "gravity"}
local function apply_physics_override(player, overrides)
    if player_monoids then
        for _, attr in pairs(physics_attrs) do
            if overrides[attr] then
                player_monoids[attr]:add_change(player, overrides[attr], "hangglider:glider")
            end
        end
    else
        player:set_physics_override(overrides)
    end
end

local function remove_physics_override(player, overrides)
    for _, attr in pairs(physics_attrs) do
        if overrides[attr] then
            if core.global_exists("player_monoids") then
                player_monoids[attr]:del_change(player, "hangglider:glider")
            else
                player:set_physics_override({[attr] = 1})
            end
        end
    end
end

local step_v
minetest.register_entity("hangglider:glider", {
	visual = "mesh",
	visual_size = {x = 12, y = 12},
	collisionbox = {0,0,0,0,0,0},
	mesh = "glider.obj",
	immortal = true,
	static_save = false,
	textures = {"wool_white.png","default_wood.png"},
	on_step = function(self, dtime)
		local canExist = false
		if self.object:get_attach() then
			local player = self.object:get_attach("parent")
			if player then
				local pos = player:getpos()
				local pname = player:get_player_name()
				if hangglider.use[pname] then
					local mrn_name = minetest.registered_nodes[minetest.get_node(vector.new(pos.x, pos.y-0.5, pos.z)).name]
					if mrn_name then
						if not (mrn_name.walkable or mrn_name.liquidtype ~= "none") then
							canExist = true

							if not minetestd then
								step_v = player:get_player_velocity().y
								if step_v < 0 and step_v > -3 then
									apply_physics_override(player, {speed=math.abs(step_v/2) + 0.75})
								elseif step_v <= -3 then --Cap our gliding movement speed.
									apply_physics_override(player, {speed=2.25})
								else
									remove_physics_override(player, {speed=1})
								end
								if debug then player:hud_change(hangglider.debug[pname].id, "text", step_v..', '..player:get_physics_override().gravity..', '..tostring(hangglider.airbreak[pname])) end
								apply_physics_override(player, {gravity=((step_v + 3)/20)})
							end
							--[[local vel = player:get_player_velocity()
							if debug then player:hud_change(hangglider.debug[pname].id, "text", vel.y..', '..grav..', '..tostring(hangglider.airbreak[pname])) end

							player:set_physics_override({gravity = (vel.y + 2.0)/20})
						]]end
					end
				end
				if not hangglider.can_fly(pname,pos) then
				    if not self.warned then -- warning shot
						self.warned = 0
						hangglider.shot_sound(pos)
						minetest.chat_send_player(pname, "Protected area! You will be shot down in two seconds by anti-aircraft guns!")
				    end
				    self.warned = self.warned + dtime
				    if self.warned > 2 then -- shoot down
						player:set_hp(1)
						player:get_inventory():remove_item("main", ItemStack("hangglider:hangglider"))
						hangglider.shot_sound(pos)
						canExist = false
				    end
				end
				if not canExist then

					if not minetestd then
						remove_physics_override(player, {
						gravity=1,
						jump = 1,
						speed = 1,})
					end
					hangglider.use[pname] = false
					if HUD_Overlay then
					player:hud_change(hangglider.id[pname], "text", "blank.png")
					end
					--hangglider.airbreak[pname] = false
				end
			end
		end
		if not canExist then
			self.object:set_detach()
			self.object:remove()
		end
	end
})

minetest.register_on_dieplayer(function(player)
	remove_physics_override(player, {
		gravity = 1,
		jump = 1,
	})
	hangglider.use[player:get_player_name()] = false
end)

minetest.register_on_joinplayer(function(player)
	local pname = player:get_player_name()
	remove_physics_override(player, {
		gravity = 1,
		jump = 1,
	})
	hangglider.use[pname] = false
	if HUD_Overlay then
	hangglider.id[pname] = player:hud_add({
		hud_elem_type = "image",
		text = "blank.png",
		position = {x=0, y=0},
		scale = {x=-100, y=-100},
		alignment = {x=1, y=1},
		offset = {x=0, y=0}
	}) end
	if debug then
		hangglider.debug[pname] = {id = player:hud_add({hud_elem_type = "text",
			position = {x=0.5, y=0.1},
			text = "-",
			number = 0xFF0000}),  -- red text
			-- ht = {50,50,50},
		}
	end
	--hangglider.airbreak[pname] = false
end)

minetest.register_on_leaveplayer(function(player)
	local pname = player:get_player_name()
	hangglider.use[pname] = nil
	if HUD_Overlay then hangglider.id[pname] = nil end
	if debug then hangglider.debug[pname] = nil end
	--hangglider.airbreak[pname] = nil
end)

minetest.register_tool("hangglider:hangglider", {
	description = "Glider",
	inventory_image = "glider_item.png",
	stack_max=1,
	on_use = function(itemstack, player, pointed_thing)
		if not player then
			return
		end
		local pos = player:get_pos()
		local pname = player:get_player_name()
		if not hangglider.use[pname] then --Equip
			minetest.sound_play("bedsheet", {pos=pos, max_hear_distance = 8, gain = 1.0})
			if HUD_Overlay then player:hud_change(hangglider.id[pname], "text", "glider_struts.png") end
			local airbreak = false
			local vel = player:get_player_velocity().y
			--[[if vel < -1.5 then  -- engage mid-air, falling fast, so stop but ramp velocity more quickly
				--hangglider.airbreak[pname] = true
				airbreak = true
				local stopper = minetest.add_entity(pos, "hangglider:airstopper")
				minetest.after(0, function(stopper, player) --"Extreme Measures"
					stopper:set_pos(player:get_pos())
					stopper:get_luaentity().attach = player
					player:set_attach( stopper, "", {x=0,y=0,z=0}, {x=0,y=0,z=0})
				end, stopper, player)
			end]]
			if not airbreak then
				if moveModelUp then
					minetest.add_entity(pos, "hangglider:glider"):set_attach(player, "", {x=0,y=10,z=0}, {x=0,y=0,z=0})
				else
					minetest.add_entity(pos, "hangglider:glider"):set_attach(player, "", {x=0,y=0,z=0}, {x=0,y=0,z=0})
				end
			end
			hangglider.use[pname] = true
			apply_physics_override(player, {jump = 0})
			-- if minetest 0.4.x use this:

			-- if minetest 5.x use this:
			-- minetest.add_entity(player:get_pos(), "hangglider:glider"):set_attach(player, "", {x=0,y=10,z=0}, {x=0,y=0,z=0})
			itemstack:set_wear(itemstack:get_wear() + 255)
			return itemstack
		elseif hangglider.use[pname] then --Unequip
			if HUD_Overlay then player:hud_change(hangglider.id[pname], "text", "default_wood.png^[colorize:#0000:255") end
			hangglider.use[pname] = false
		end
	end,
	sound = {breaks = "default_tool_breaks"},
})

minetest.register_craft({
	output = "hangglider:hangglider",
	recipe = {
		{"wool:white", "wool:white", "wool:white"},
		{"default:stick", "mesecons_materials:glue", "default:stick"},
		{"mesecons_materials:glue", "default:stick", "mesecons_materials:glue"},
	}
})


code:
name = hangglider
author = Piezo
description = Adds a hang-glider for players to soar from heights.
depends = default, wool
optional_depends = minetest_systemd, areas, player_monoids


code:
Minetest 5.4 mod: Not So Simple Helicopter
========================================

This is the "Not So Simple Helicopter", fork of the old "Simple Helicopter".
This version is more expensive to produce and that uses biofuel from crops. So far we have a helicopter that consumes fuel, has its consumption changed according to the level of flight. It dependes on a second mod (based on the wine mod), with a distiller that allows to transform some inputs into biofuel and fly with them.
A passenger can go onboard when the pilot is inside
Now the direction is controlled by A and D keys, but if you want do change direction by mouse, just type E key to change the flight dynamics and A and D just tilt the helicopter to sides again

It can be painted using dye of any color you want, you must punch the seat with the dye.

Biofuel mod can be found here: https://github.com/APercy/minetest_biofuel

-----------------------
originally Simple helicopter by Pavel_S
reworked by DS
re-reworked by A_Percy

License of source code:
-----------------------
original code by Pavel_S: GPL_v2 (see file LICENSE)
changes / complete rework by DS and A_Percy
`matrix.lua` file: CC0

License of media (textures and sounds):
---------------------------------------

helicopter_motor.ogg by  Robinhood76 | License: Attribution Noncommercial

helicopter_water_driblet.png by DS | License: CC0

helicopter model and texture:

Helicube is a model made by Alexsandro Percy, based in original model aesthetic but made from zero. But using on rotors an adaptation of the texture from 3D model made by Melkor and his animations.

the item textures are probably by Pavel_S