Sound improvements

lib/soundloop.lua

@@ -0,0 +1,57 @@
+local soundloop = {}
+local sounds = {}
+
+local function parse_sound(sound)
+	if type(sound) == "string" then
+		return { name = sound, gain = 1, pitch = 1 }
+	end
+	if sound.gain == nil then sound.gain = 1 end
+	if sound.pitch == nil then sound.pitch = 1 end
+	return sound
+end
+
+soundloop.play = function(player, sound, fade)
+	sound = parse_sound(sound)
+	if fade == nil then fade = 1 end
+	local step
+	local handle
+	local start_gain
+	if sounds[player] == nil then sounds[player] = {} end
+	if sounds[player][sound.name] == nil then
+		step = sound.gain / fade
+		start_gain = 0
+	elseif sounds[player][sound.name] ~= sound.gain then
+		minetest.sound_stop(sounds[player][sound.name].handle)
+		start_gain = sounds[player][sound.name].gain
+		local change = sound.gain - start_gain
+		step = change / fade
+	else
+		return
+	end
+	handle = minetest.sound_play(sound.name, {
+		to_player = player,
+		loop = true,
+		gain = 0
+	})
+	sounds[player][sound.name] = {
+		gain = sound.gain,
+		handle = handle
+	}
+	minetest.sound_fade(handle, step, sound.gain)
+	return handle
+end
+
+soundloop.stop = function(player, sound, fade)
+	sound = parse_sound(sound)
+	if sounds[player] == nil or sounds[player][sound.name] == nil then
+		return
+	end
+	if fade == nil then fade = 1 end
+	local handle = sounds[player][sound.name].handle
+	local step = -sounds[player][sound.name].gain / fade
+	minetest.sound_fade(handle, step, 0)
+	sounds[player][sound.name].gain = 0
+	minetest.after(fade, minetest.sound_stop, handle)
+end
+
+return soundloop