fix snowfall and pines

src/falling_snow.lua

@@ -80,23 +80,28 @@ local PERSISTENCE3 = 0.5 -- 0.5
 local SCALE3 = 250 -- 250
 
 --Get snow at position.
+local rarity, perlin_scale
 local function get_snow(pos)
 	--Legacy support.
-	if weather_legacy == "snow" then
-		local perlin1 = minetest.get_perlin(112,3, 0.5, 150)
-		if perlin1:get2d({x=pos.x, y=pos.z}) <= 0.53 then
-			return false
-		end
-
-		-- disable falling snow in desert
-		local desert_perlin = minetest.get_perlin(SEEDDIFF3, OCTAVES3, PERSISTENCE3, SCALE3)
-		local noise3 = desert_perlin:get2d({x=pos.x+150,y=pos.z+50}) -- Offsets must match minetest mapgen desert perlin.
-		if noise3 > 0.35 then -- Smooth transition 0.35 to 0.45.
-			return false
-		end
-		return true
+	if weather_legacy ~= "snow" then
+		return false
 	end
-	return false
+	if not rarity then
+		rarity = snow.mapgen.smooth_rarity_min
+		perlin_scale = snow.mapgen.perlin_scale
+	end
+	local perlin1 = minetest.get_perlin(112,3, 0.5, perlin_scale)
+	if perlin1:get2d({x=pos.x, y=pos.z}) < rarity then
+		return false
+	end
+
+	-- disable falling snow in desert
+	local desert_perlin = minetest.get_perlin(SEEDDIFF3, OCTAVES3, PERSISTENCE3, SCALE3)
+	local noise3 = desert_perlin:get2d({x=pos.x+150,y=pos.z+50}) -- Offsets must match minetest mapgen desert perlin.
+	if noise3 > 0.35 then -- Smooth transition 0.35 to 0.45.
+		return false
+	end
+	return true
 end
 
 local addvectors = vector and vector.add
@@ -159,20 +164,21 @@ local function snow_fall(pos, player, animate)
 
 	pos = {x=pos.x, y=ground_y, z=pos.z}
 
-  	if get_snow(pos) then
-  		if animate then
-			local spos = {x=pos.x, y=ground_y+10, z=pos.z}
-			minetest.add_particlespawner(get_snow_particledef({
-				minpos = addvectors(spos, {x=-9, y=3, z=-9}),
-				maxpos = addvectors(spos, {x= 9, y=5, z= 9}),
-				vel = {x=0, y=-1, z=-1},
-				acc = {x=0, y=0, z=0},
-				playername = player:get_player_name()
-			}))
-		end
-		snow.place(pos, true)
-		--minetest.place_node({x=pos.x, y=pos.y+2, z=pos.z}, {name="default:snow"}) -- LazyJ
+  	if not get_snow(pos) then
+		return
 	end
+	if animate then
+		local spos = {x=pos.x, y=ground_y+10, z=pos.z}
+		minetest.add_particlespawner(get_snow_particledef({
+			minpos = addvectors(spos, {x=-9, y=3, z=-9}),
+			maxpos = addvectors(spos, {x= 9, y=5, z= 9}),
+			vel = {x=0, y=-1, z=-1},
+			acc = {x=0, y=0, z=0},
+			playername = player:get_player_name()
+		}))
+	end
+	snow.place(pos, true)
+	--minetest.place_node({x=pos.x, y=pos.y+2, z=pos.z}, {name="default:snow"}) -- LazyJ
 end
 
 -- Snow

src/mapgen.lua

@@ -13,6 +13,32 @@ saplings grow into trees. --]]
 -- Part 1: To disable the mapgen, add the *starting* comment under this line.
 
 
+snow.mapgen = snow.mapgen or {}
+local mg = snow.mapgen
+
+-- perlin noise "hills" are not peaks but looking like sinus curve
+local function upper_rarity(rarity)
+	return math.sign(rarity)*math.sin(math.abs(rarity)*math.pi/2)
+end
+
+local rarity = 18 --snow.mapgen_rarity
+local size = 210 --snow.mapgen_size
+
+local nosmooth_rarity = 1-rarity/50
+local perlin_scale = size*100/rarity
+mg.perlin_scale = perlin_scale
+local smooth_rarity_max, smooth_rarity_min, smooth_rarity_dif
+local smooth = snow.smooth_biomes
+if smooth then
+	local smooth_trans_size = 4 --snow.smooth_trans_size
+	mg.smooth_rarity_max = upper_rarity(nosmooth_rarity+smooth_trans_size*2/perlin_scale)
+	mg.smooth_rarity_min = upper_rarity(nosmooth_rarity-smooth_trans_size/perlin_scale)
+	mg.smooth_rarity_dif = mg.smooth_rarity_max-mg.smooth_rarity_min
+end
+nosmooth_rarity = upper_rarity(nosmooth_rarity)
+mg.nosmooth_rarity = nosmooth_rarity
+
+
 --Identify the mapgen.
 minetest.register_on_mapgen_init(function(MapgenParams)
 	local mgname = MapgenParams.mgname
@@ -31,8 +57,6 @@ end)
 -- To complete the commenting-out add the *closing* comment under this line.
 
 
-
-
 local pine_tree = {
 	axiom="TABff",
 	rules_a="[&T+f+ff+ff+ff+f]GA",
@@ -66,7 +90,6 @@ local xmas_tree = {
 --Makes pine tree
 function snow.make_pine(pos,snow,xmas)
 	local minetest = minetest
-	local perlin1 = minetest.get_perlin(112,3, 0.5, 150)
 	local try_node = function(pos, node)
 		local n = minetest.get_node(pos).name
 		if n == "air"
@@ -95,7 +118,7 @@ function snow.make_pine(pos,snow,xmas)
 	if xmas then
 		try_node({x=pos.x,y=pos.y+7,z=pos.z},{name="snow:star_lit"}) -- Added lit star. ~ LazyJ
 	elseif snow
-	and perlin1:get2d({x=pos.x,y=pos.z}) > 0.53 then
+	and minetest.get_perlin(112,3, 0.5, perlin_scale):get2d({x=pos.x,y=pos.z}) > nosmooth_rarity then
 		try_node({x=pos.x,y=pos.y+7,z=pos.z},{name="default:snow"})
 	end
 end
@@ -109,7 +132,7 @@ function snow.voxelmanip_pine(pos,a,data)
 	local c_pinetree = minetest.get_content_id("default:pinetree")
 	local c_air = minetest.get_content_id("air")
 
-	local perlin1 = minetest.get_perlin(112,3, 0.5, 150)
+	local perlin1 = minetest.get_perlin(112,3, 0.5, perlin_scale)
 	for z = -1,1 do
 		local z = pos.z + z
 		for x = -1,1 do
@@ -120,7 +143,7 @@ function snow.voxelmanip_pine(pos,a,data)
 				data[a:index(x,pos.y+i,z)] = c_pine_needles
 				if x ~= 0
 				and z ~= 0
-				and perlin1:get2d({x=x,y=z}) > 0.53 then
+				and perlin1:get2d({x=x,y=z}) > nosmooth_rarity then
 					local abovenode = a:index(x,pos.y+i+1,z)
 					data[abovenode] = c_snow
 				end
@@ -135,16 +158,16 @@ function snow.voxelmanip_pine(pos,a,data)
 		data[a:index(x-1,y,z)] = c_pine_needles
 		data[a:index(x,y,z+1)] = c_pine_needles
 		data[a:index(x,y,z-1)] = c_pine_needles
-		if perlin1:get2d({x=x+1,y=z}) > 0.53 then
+		if perlin1:get2d({x=x+1,y=z}) > nosmooth_rarity then
 			data[a:index(x+1,y+1,z)] = c_snow
 		end
-		if perlin1:get2d({x=x+1,y=z}) > 0.53 then
+		if perlin1:get2d({x=x+1,y=z}) > nosmooth_rarity then
 			data[a:index(x-1,y+1,z)] = c_snow
 		end
-		if perlin1:get2d({x=x,y=z+1}) > 0.53 then
+		if perlin1:get2d({x=x,y=z+1}) > nosmooth_rarity then
 			data[a:index(x,y+1,z+1)] = c_snow
 		end
-		if perlin1:get2d({x=x,y=z-1}) > 0.53 then
+		if perlin1:get2d({x=x,y=z-1}) > nosmooth_rarity then
 			data[a:index(x,y+1,z-1)] = c_snow
 		end
 	end
@@ -153,7 +176,7 @@ function snow.voxelmanip_pine(pos,a,data)
 	end
 	data[a:index(pos.x,pos.y+5,pos.z)] = c_pine_needles
 	data[a:index(pos.x,pos.y+6,pos.z)] = c_pine_needles
-	if perlin1:get2d({x=pos.x,y=pos.z}) > 0.53 then
+	if perlin1:get2d({x=pos.x,y=pos.z}) > nosmooth_rarity then
 		data[a:index(pos.x,pos.y+7,pos.z)] = c_snow
 	end
 end

src/mapgen_v6.lua

@@ -11,9 +11,12 @@ local np_default = {
 
 -- 2D noise for coldness
 
+local mg = snow.mapgen
+local scale = mg.perlin_scale
 local np_cold = {
 	offset = 0,
 	scale = 1,
+	spread = {x=scale, y=scale, z=scale},
 	seed = 112,
 	octaves = 3,
 	persist = 0.5
@@ -121,26 +124,11 @@ local function define_contents()
 	replacements = snow.known_plants or {}
 end
 
--- perlin noise "hills" are not peaks but looking like sinus curve
-local function upper_rarity(rarity)
-	return math.sign(rarity)*math.sin(math.abs(rarity)*math.pi/2)
-end
-
-local rarity = 18 --snow.mapgen_rarity
-local size = 210 --snow.mapgen_size
-
-local nosmooth_rarity = 1-rarity/50
-local perlin_scale = size*100/rarity
-np_cold.spread = {x=perlin_scale, y=perlin_scale, z=perlin_scale}
-local smooth_rarity_max, smooth_rarity_min, smooth_rarity_dif
 local smooth = snow.smooth_biomes
-if smooth then
-	local smooth_trans_size = 4 --snow.smooth_trans_size
-	smooth_rarity_max = upper_rarity(nosmooth_rarity+smooth_trans_size*2/perlin_scale)
-	smooth_rarity_min = upper_rarity(nosmooth_rarity-smooth_trans_size/perlin_scale)
-	smooth_rarity_dif = smooth_rarity_max-smooth_rarity_min
-end
-nosmooth_rarity = upper_rarity(nosmooth_rarity)
+local smooth_rarity_max = mg.smooth_rarity_max
+local smooth_rarity_min = mg.smooth_rarity_min
+local smooth_rarity_dif = mg.smooth_rarity_dif
+local nosmooth_rarity = mg.nosmooth_rarity
 
 minetest.register_on_generated(function(minp, maxp, seed)
 	local t1 = os.clock()