local areaSize = 128 --128
local brickSize = 4 --4
local noiseScale = 32 --32
local noiseMagnitude = 50 --50
local aboutHeight = 0.65 --0.65
local playerGenRadius = 64 --64

--the level indicates the bottom of the region
local snowLevel = 128
local snowBottom = 40 --snow is generated differently
local rockLevel = 64
local grassLevel = 12
local beachLevel = 8
local waterLevel = 7

local topSeedX = math.random() --screw DRY
local topSeedY = math.random()
local midSeedX = math.random()
local midSeedY = math.random()
local lowSeedX = math.random()
local lowSeedY = math.random()
local biomeSeedX = math.random()
local biomeSeedY = math.random()

--local g = Instance.new("Model", game.Workspace)

function genTerrainBlock(i, j)
	--[[
	local b = Instance.new("Part", g)
	b.Size = Vector3.new(brickSize,height,brickSize)
	b.Position = Vector3.new(i*brickSize,height/2,j*brickSize)
	b.Anchored = true
	local brickColor = BrickColor.new("Deep blue") --fill everything unchanged with water
	]]--
	local noiseLayers = {(math.noise(i/noiseScale+topSeedX, j/noiseScale+topSeedY)+0.5)*noiseMagnitude,
						 (math.noise(i/(noiseScale/2)+midSeedX, j/(noiseScale/2)+midSeedY)+0.5)*noiseMagnitude*0.7,
						 (math.noise(i/(noiseScale/5)+lowSeedX, j/(noiseScale/5)+lowSeedY)+0.5)*noiseMagnitude*0.4
						}
	local height = 0.0
	for k,v in pairs(noiseLayers) do
		height = height + v
	end
	if height < 1 then
		height = 2
	end
	height = math.ceil(math.pow(height, (math.noise(i/(noiseScale*4)+biomeSeedX, j/(noiseScale*4)+biomeSeedY)+aboutHeight)))
	--print(tostring(height))
	if height < 7 then
		height = 6
	end
	local terrainColor = Enum.Material.Water
	if height >= beachLevel and height < grassLevel then
		--brickColor = BrickColor.new("Pastel yellow")
		terrainColor = Enum.Material.Sand
	elseif height >= grassLevel and height < rockLevel then
		--brickColor = BrickColor.new("Camo")
		if math.noise(i/noiseScale+biomeSeedX, j/noiseScale+biomeSeedY) > 0 then
			terrainColor = Enum.Material.Grass
		else
			terrainColor = Enum.Material.Ground
		end
	elseif height >= rockLevel and height < snowLevel then
		--brickColor = BrickColor.new("Dark stone grey")
		terrainColor = 896 --Enum.Material.Rock isn't a thing apparently
	elseif height >= snowLevel then
		--brickColor = BrickColor.new("Institutional white")
		terrainColor = Enum.Material.Snow
	end
	--add snow
	if height >= snowBottom then
		if math.random() < (height-snowBottom)/(snowLevel-snowBottom) then
			terrainColor = Enum.Material.Snow
		end
	end
	game.Workspace.Terrain:FillRegion(Region3.new(Vector3.new(i*brickSize,-1300,j*brickSize),
												  Vector3.new(i*brickSize+brickSize,height,j*brickSize+brickSize)):ExpandToGrid(4),
									  4, terrainColor)
	--b.BrickColor = brickColor
	--game.Workspace.Terrain:FillBlock(b.CFrame, b.Size, terrainColor)
	--b:Remove()
end

for i=-areaSize,areaSize do
	for j=-areaSize,areaSize do
		genTerrainBlock(i,j)
	end
end

--[[
game.Players.PlayerAdded:connect(function(player)
	player.CharacterAdded:connect(function(character)
		while player ~= nil do
			local cPos = character.Head.Position
			for i=cPos.X-playerGenRadius,cPos.X+playerGenRadius do
				for j=cPos.Z-playerGenRadius,cPos.Z+playerGenRadius do
					local material, occupancy = game.Workspace.Terrain:ReadVoxels(
																				  Region3.new(
																				  			  Vector3.new(i, 0, j),
																				  			  Vector3.new(i+0.1, 0.1, j+0.1) --epsilon
																							  ):ExpandToGrid(4), 4)
					if material[1][1][1] == Enum.Material.Air then
						genTerrainBlock(i/brickSize,j/brickSize)
					end
				end
			end
			wait()
		end
	end)
end)
--]]