Add rain sound. Use timer for globalstep cycle. Improve raindrop texture. Disable rainfall in deserts below savanna-desert border voronoi line. Sample light at player head position for precipitation while swimming

README.txt

@@ -1,4 +1,11 @@
 snowdrift 0.5.0 by paramat
-For Minetest 0.4.12 and later
+For Minetest 0.4.15 and later
 Depends default
-Licenses: Source code MIT. Media (textures) CC BY-SA (3.0)
+
+Licenses:
+Source code:
+MIT by paramat
+Media:
+Textures CC BY-SA (3.0) by paramat
+Sounds CC BY (3.0) by inchadney
+http://freesound.org/people/inchadney/sounds/58835/ 

init.lua

@@ -1,10 +1,10 @@
 -- Parameters
 
-local PRECSPR = 11 -- Time scale for precipitation variation in minutes
-local PRECOFF = 0.8 -- Precipitation noise threshold offset
-local PROCHA = 0.2 -- Per player per globalstep processing chance
-local FLAKES = 8 -- Snowflake density
-local DROPS = 16 -- Rainfall density
+local PRECSPR = 6 -- Time scale for precipitation variation in minutes
+local PRECOFF = -0.4 -- Precipitation offset, higher = rains more often
+local GSCYCLE = 0.5 -- Globalstep cycle (seconds)
+local FLAKES = 16 -- Snowflakes per cycle
+local DROPS = 32 -- Raindrops per cycle
 local NISVAL = 39 -- Clouds RGB value at night
 local DASVAL = 175 -- Clouds RGB value in daytime
 
@@ -58,17 +58,25 @@ local nobj_prec = nil
 
 -- Globalstep function
 
+local handles = {}
+local timer = 0
+
 minetest.register_globalstep(function(dtime)
+	timer = timer + dtime
+	if timer < GSCYCLE then
+		return
+	end
+
+	timer = 0
+
 	for _, player in ipairs(minetest.get_connected_players()) do
-		-- Randomise and spread processing load
-		if math.random() > PROCHA then
-			return
-		end
+		local player_name = player:get_player_name()
 
 		local ppos = player:getpos()
 		local pposx = math.floor(ppos.x)
-		local pposy = math.floor(ppos.y)
+		local pposy = math.floor(ppos.y) + 2 -- Precipitation when swimming
 		local pposz = math.floor(ppos.z)
+		local ppos = {x = pposx, y = pposy, z = pposz}
 
 		local nobj_temp = nobj_temp or minetest.get_perlin(np_temp)
 		local nobj_humid = nobj_humid or minetest.get_perlin(np_humid)
@@ -78,16 +86,22 @@ minetest.register_globalstep(function(dtime)
 		local nval_humid = nobj_humid:get2d({x = pposx, y = pposz})
 		local nval_prec = nobj_prec:get2d({x = os.clock() / 60, y = 0})
 
-		-- Biome system: frozen biomes below heat 35,
-		-- deserts below humidity 20
+		-- Biome system: frozen biomes below heat 35.
+		-- deserts below line 14 * t - 95 * h = -1496
+		-- h = (14 * t + 1496) / 95
+		-- h = 14/95 * t + 1496/95 where 1496/95 is y intersection
+		-- h - 14/95 t = 1496/95 y intersection
+		-- so area above line is
+		-- h - 14/95 t > 1496/95
 		local freeze = nval_temp < 35
-		local precip = nval_prec > (nval_humid - 50) / 50 + PRECOFF
+		local precip = nval_prec < (nval_humid - 50) / 50 + PRECOFF and
+			nval_humid - (14 / 95) * nval_temp > 1496 / 95
 
 		-- Check if player is outside
 		local outside = minetest.get_node_light(ppos, 0.5) == 15
 
 		-- Occasionally reset player sky
-		if math.random() < 0.05 then
+		if math.random() < 0.1 then
 			if precip then
 				-- Set overcast sky
 				local sval
@@ -114,6 +128,14 @@ minetest.register_globalstep(function(dtime)
 			end
 		end
 
+		if not precip or not outside or freeze then
+			if handles[player_name] then
+				-- Stop sound if playing
+				minetest.sound_stop(handles[player_name])
+				handles[player_name] = nil
+			end
+		end
+
 		if precip and outside then
 			-- Precipitation
 			if freeze then
@@ -162,6 +184,21 @@ minetest.register_globalstep(function(dtime)
 						playername = player:get_player_name()
 					})
 				end
+
+				if not handles[player_name] then
+					-- Start sound if not playing
+					local handle = minetest.sound_play(
+						"snowdrift_rain",
+						{
+							to_player = player_name,
+							gain = 0.2,
+							loop = true,
+						}
+					)
+					if handle then
+						handles[player_name] = handle
+					end
+				end
 			end
 		end
 	end

license.txt

@@ -2,7 +2,7 @@ License of source code
 ----------------------
 
 The MIT License (MIT)
-Copyright (C) 2014-2016 paramat
+Copyright (C) 2017 paramat
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of this
 software and associated documentation files (the "Software"), to deal in the Software
@@ -22,3 +22,70 @@ DEALINGS IN THE SOFTWARE.
 
 For more details:
 https://opensource.org/licenses/MIT
+
+
+License of media (textures)
+---------------------------
+
+Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)
+Copyright (C) 2017 paramat
+
+You are free to:
+Share — copy and redistribute the material in any medium or format.
+Adapt — remix, transform, and build upon the material for any purpose, even commercially.
+The licensor cannot revoke these freedoms as long as you follow the license terms.
+
+Under the following terms:
+
+Attribution — You must give appropriate credit, provide a link to the license, and
+indicate if changes were made. You may do so in any reasonable manner, but not in any way
+that suggests the licensor endorses you or your use.
+
+ShareAlike — If you remix, transform, or build upon the material, you must distribute
+your contributions under the same license as the original.
+
+No additional restrictions — You may not apply legal terms or technological measures that
+legally restrict others from doing anything the license permits.
+
+Notices:
+
+You do not have to comply with the license for elements of the material in the public
+domain or where your use is permitted by an applicable exception or limitation.
+No warranties are given. The license may not give you all of the permissions necessary
+for your intended use. For example, other rights such as publicity, privacy, or moral
+rights may limit how you use the material.
+
+For more details:
+http://creativecommons.org/licenses/by-sa/3.0/
+
+
+License of media (sounds)
+-------------------------
+
+Attribution 3.0 Unported (CC BY 3.0)
+Copyright (C) 2008 inchadney
+
+You are free to:
+Share — copy and redistribute the material in any medium or format.
+Adapt — remix, transform, and build upon the material for any purpose, even commercially.
+The licensor cannot revoke these freedoms as long as you follow the license terms.
+
+Under the following terms:
+
+Attribution — You must give appropriate credit, provide a link to the license, and
+indicate if changes were made. You may do so in any reasonable manner, but not in any way
+that suggests the licensor endorses you or your use.
+
+No additional restrictions — You may not apply legal terms or technological measures that
+legally restrict others from doing anything the license permits.
+
+Notices:
+
+You do not have to comply with the license for elements of the material in the public
+domain or where your use is permitted by an applicable exception or limitation.
+No warranties are given. The license may not give you all of the permissions necessary
+for your intended use. For example, other rights such as publicity, privacy, or moral
+rights may limit how you use the material.
+
+For more details:
+http://creativecommons.org/licenses/by/3.0/