create biome system

2 files changed, 163 insertions, 59 deletions

diff --git a/mods/vzxv_worldgen/biome.lua b/mods/vzxv_worldgen/biome.lua
new file mode 100644
index 0000000..ba7e189
--- /dev/null
+++ b/mods/vzxv_worldgen/biome.lua
@@ -0,0 +1,159 @@
+
+vzxv.biome_generator = {}
+
+function vzxv.biome_generator.new(minp, maxp)
+	local self = setmetatable({}, {__index = vzxv.biome_generator})
+	self.minp = minp
+	self.maxp = maxp
+	self.generated_noisemaps = {}
+	self.generated_3d_noisemaps = {}
+
+	return self
+end
+
+local noise_params = {
+	elevation = {
+		seed = 1,
+		offset = -50, 
+		scale = 50,
+		spread = {x=2500,y=2500,z=500},
+		octaves = 5,
+		persistence = 0.8,
+		lacunarity = 2.0,
+		flags = "defaults, absvalue",
+	},
+}
+
+function vzxv.biome_generator:noisemap(mapname, pos)
+	local map = self.generated_noisemaps[mapname]
+	if not map then
+		local nm = PerlinNoiseMap(noise_params[mapname], {
+			x = self.maxp.x - self.minp.x + 1,
+			y = self.maxp.z - self.minp.z + 1,
+		})
+		map = nm:get_2d_map { x = self.minp.x, y = self.minp.z }
+		self.generated_noisemaps[mapname] = map
+	end
+	return map[pos.z - self.minp.z + 1][pos.x - self.minp.x + 1]
+end
+
+function vzxv.biome_generator:noisemap_3d(mapname, pos)
+	local map = self.generated_3d_noisemaps[mapname]
+	if not map then
+		local nm = PerlinNoiseMap(noise_params[mapname], {
+			x = self.maxp.x - self.minp.x + 1,
+			y = self.maxp.y - self.minp.y + 1,
+			z = self.maxp.z - self.minp.z + 1,
+		})
+		map = nm:get_3d_map
+			{ x = self.minp.x, y = self.minp.y, z = self.minp.z }
+		self.generated_noisemaps[mapname] = map
+	end
+	local x = pos.x - self.minp.x + 1
+	local y = pos.y - self.minp.y + 1
+	local z = pos.z - self.minp.z + 1
+	return map[z][y][x]
+end
+
+local water_level = 14
+
+function vzxv.biome_generator:get_biome(pos)
+	-- TODO: underground biomes
+	if pos.y < -75 then
+		return "underground"
+	-- TODO: sky biomes
+	elseif pos.y > 120 then
+		return pos.y < 7500 and "sky" or "space"
+	else
+		if self:noisemap("elevation", pos) <= water_level + 2 then
+			return "sea"
+		else
+			-- TODO: surface biomes
+			return "surface"
+		end
+	end
+end
+
+local id = minetest.get_content_id
+
+local biomes = {}
+
+function biomes.surface(pos, gen)
+	local height = gen:noisemap("elevation", pos)
+	if pos.y > height then
+		return
+	elseif pos.y == math.floor(height) then
+		if math.random(256) == 1 then
+			-- schedule trees to be generated if they haven't been
+			if not gen.trees_tbg then
+				gen.trees_tbg = {}
+				minetest.after(0, function()
+					for _, pos in ipairs(gen.trees_tbg) do
+						vzxv.generate_tree(pos)
+					end
+					gen.trees_tbg = {}
+				end)
+			end
+			table.insert(gen.trees_tbg, pos)
+		end
+		return id "vzxv:moistgrass"
+	elseif pos.y > height - 5 then
+		return id "vzxv:moistdirt"
+	else
+		return id "vzxv:stone"
+	end
+end
+
+function biomes.sea(pos, gen)
+	local height = gen:noisemap("elevation", pos)
+	if pos.y > height then
+		if pos.y < water_level then
+			return id "vzxv:water"
+		else
+			return
+		end
+	elseif pos.y > height - 4 then
+		return id "vzxv:sand"
+	else
+		return id "vzxv:stone"
+	end
+end
+
+function biomes.underground(pos)
+	return id "vzxv:stone"
+end
+
+local function generate_block(gen, pos, data, va)
+	local biome = gen:get_biome(pos)
+	return biomes[biome] and biomes[biome](pos, gen, data, va)
+end
+
+local data = {}
+function vzxv.biome_generator:generate_chunk()
+	-- sky is empty. when sky biomes are added, add a maximum position here
+	if self.minp.y > 120 then
+		return
+	end
+
+	local voxmn, vmin, vmax = minetest.get_mapgen_object "voxelmanip"
+	local va = VoxelArea:new { MinEdge = vmin, MaxEdge = vmax }
+
+	voxmn:get_data(data)
+	for x=self.minp.x, self.maxp.x do
+		for z=self.minp.z, self.maxp.z do
+			for y=self.minp.y, self.maxp.y do
+				local pos = { x = x, y = y, z = z }
+				local block = generate_block(self, pos, data, va)
+				local i = va:index(x, y, z)
+				if block then
+					data[i] = block
+				end
+			end
+		end
+	end
+	
+	voxmn:set_data(data)
+	voxmn:update_liquids()
+	voxmn:write_to_map(true)
+	voxmn:calc_lighting()
+end
diff --git a/mods/vzxv_worldgen/init.lua b/mods/vzxv_worldgen/init.lua
index a8d398f..17ea168 100644
--- a/mods/vzxv_worldgen/init.lua
+++ b/mods/vzxv_worldgen/init.lua
@@ -1,69 +1,14 @@
+
 minetest.set_mapgen_setting('mg_name','singlenode',true)
 minetest.set_mapgen_setting('flags','nolight',true)
 
-local stone = minetest.get_content_id("vzxv:stone")
-local dirt = minetest.get_content_id("vzxv:moistdirt")
-local grass = minetest.get_content_id("vzxv:moistgrass")
-local water = minetest.get_content_id("vzxv:water")
-local sand = minetest.get_content_id("vzxv:sand")
-local tree = minetest.get_content_id("vzxv_trees:seed")
+vzxv.include "biome.lua"
 
-local data = {}
-local surface_height = 6
-local water_level = 14
-local trees_tbg = {}
--- chunks
 minetest.register_on_generated(function(minp,maxp,seed)
-	local voxmn, vmin, vmax = minetest.get_mapgen_object("voxelmanip")
-	local va = VoxelArea:new{MinEdge=vmin,MaxEdge=vmax}
-
-	local noisemap = PerlinNoiseMap({
-		seed = 1,
-		offset = -50, 
-		scale = 50,
-		spread = {x=2500,y=2500,z=500},
-		octaves = 5,
-		persistence = 0.8,
-		lacunarity = 2.0,
-		flags = "defaults, absvalue",
-	}, {x=maxp.x-minp.x+1,y=maxp.z-minp.z+1})
-	local heightmap = noisemap:get_2d_map{x=minp.x,y=minp.z}
-
-	voxmn:get_data(data)
-	for x=minp.x, maxp.x do
-		for z=minp.z, maxp.z do
-			local height = heightmap[z-minp.z+1][x-minp.x+1]
-			for y=minp.y, maxp.y do
-				local i = va:index(x,y,z)
-				local underwater = y < water_level
-				if y < height then
-					local shore = height <= water_level
-					local surface = shore and sand or dirt
-					data[i] = y > height - surface_height and surface or stone
-					if y == math.floor(height) and not underwater then
-						if math.random(0,255) == 0 then
-							table.insert(trees_tbg,{x=x,y=y,z=z})
-						end
-						data[i] = grass
-					end
-				elseif underwater then
-					data[i] = water
-				end
-			end
-		end
-	end
-	
-	voxmn:set_data(data)
-	voxmn:update_liquids()
-	voxmn:write_to_map(true)
-	voxmn:calc_lighting()
-	
+	local gen = vzxv.biome_generator.new(minp, maxp)
+	gen:generate_chunk()
 	minetest.after(0,function()
 		minetest.fix_light(minp,maxp)
-		for i, v in ipairs(trees_tbg) do
-			vzxv.generate_tree(v)
-		end
-		trees_tbg = {}
 	end)
 end)