technic/technic_worldgen/oregen.lua

local uranium_params = {offset = 0, scale = 1, spread = {x = 100, y = 100, z = 100}, seed = 420, octaves = 3, persist = 0.7}
local uranium_threshold = 0.55

local chromium_params = {offset = 0, scale = 1, spread = {x = 100, y = 100, z = 100}, seed = 421, octaves = 3, persist = 0.7}
local chromium_threshold = 0.55

local zinc_params = {offset = 0, scale = 1, spread = {x = 100, y = 100, z = 100}, seed = 422, octaves = 3, persist = 0.7}
local zinc_threshold = 0.5

local lead_params = {offset = 0, scale = 1, spread = {x = 100, y = 100, z = 100}, seed = 423, octaves = 3, persist = 0.7}
local lead_threshold = 0.3

minetest.register_ore({
	ore_type         = "scatter",
	ore              = "technic:mineral_uranium",
	wherein          = "default:stone",
	clust_scarcity   = 8*8*8,
	clust_num_ores   = 4,
	clust_size       = 3,
	y_min       = -300,
	y_max       = -80,
	noise_params     = uranium_params,
	noise_threshold = uranium_threshold,
})

minetest.register_ore({
	ore_type         = "scatter",
	ore              = "technic:mineral_chromium",
	wherein          = "default:stone",
	clust_scarcity   = 8*8*8,
	clust_num_ores   = 2,
	clust_size       = 3,
	y_min       = -200,
	y_max       = -100,
	noise_params     = chromium_params,
	noise_threshold = chromium_threshold,
})

minetest.register_ore({
	ore_type         = "scatter",
	ore              = "technic:mineral_chromium",
	wherein          = "default:stone",
	clust_scarcity   = 6*6*6,
	clust_num_ores   = 2,
	clust_size       = 3,
	y_min       = -31000,
	y_max       = -200,
	flags            = "absheight",
	noise_params     = chromium_params,
	noise_threshold = chromium_threshold,
})

minetest.register_ore({
	ore_type         = "scatter",
	ore              = "technic:mineral_zinc",
	wherein          = "default:stone",
	clust_scarcity   = 8*8*8,
	clust_num_ores   = 5,
	clust_size       = 7,
	y_min       = -32,
	y_max       = 2,
	noise_params     = zinc_params,
	noise_threshold = zinc_threshold,
})

minetest.register_ore({
	ore_type         = "scatter",
	ore              = "technic:mineral_zinc",
	wherein          = "default:stone",
	clust_scarcity   = 6*6*6,
	clust_num_ores   = 4,
	clust_size       = 3,
	y_min       = -31000,
	y_max       = -32,
	flags            = "absheight",
	noise_params     = zinc_params,
	noise_threshold = zinc_threshold,
})

minetest.register_ore({
	ore_type         = "scatter",
	ore              = "technic:mineral_lead",
	wherein          = "default:stone",
	clust_scarcity   = 9*9*9,
	clust_num_ores   = 5,
	clust_size       = 3,
	y_min       = -16,
	y_max       = 16,
	noise_params     = lead_params,
	noise_threshold = lead_threshold,
})

minetest.register_ore({
	ore_type         = "scatter",
	ore              = "technic:mineral_lead",
	wherein          = "default:stone",
	clust_scarcity   = 8*8*8,
	clust_num_ores   = 5,
	clust_size       = 3,
	y_min       = -128,
	y_max       = -16,
	noise_params     = lead_params,
	noise_threshold = lead_threshold,
})

minetest.register_ore({
	ore_type         = "scatter",
	ore              = "technic:mineral_lead",
	wherein          = "default:stone",
	clust_scarcity   = 6*6*6,
	clust_num_ores   = 5,
	clust_size       = 3,
	y_min       = -31000,
	y_max       = -128,
	flags            = "absheight",
	noise_params     = lead_params,
	noise_threshold = lead_threshold,
})

-- Sulfur
local sulfur_buf = {}
local sulfur_noise= nil

minetest.register_on_generated(function(minp, maxp, seed)
	local vm, emin, emax = minetest.get_mapgen_object("voxelmanip")
	local a = VoxelArea:new{
		MinEdge = {x = emin.x, y = emin.y, z = emin.z},
		MaxEdge = {x = emax.x, y = emax.y, z = emax.z},
	}
	local data = vm:get_data(sulfur_buf)
	local pr = PseudoRandom(17 * minp.x + 42 * minp.y + 101 * minp.z)
	sulfur_noise = sulfur_noise or minetest.get_perlin(9876, 3, 0.5, 100)

	local c_lava = minetest.get_content_id("default:lava_source")
	local c_lava_flowing = minetest.get_content_id("default:lava_flowing")
	local c_stone = minetest.get_content_id("default:stone")
	local c_sulfur = minetest.get_content_id("technic:mineral_sulfur")

	local grid_size = 5
	for x = minp.x + math.floor(grid_size / 2), maxp.x, grid_size do
	for y = minp.y + math.floor(grid_size / 2), maxp.y, grid_size do
	for z = minp.z + math.floor(grid_size / 2), maxp.z, grid_size do
		local c = data[a:index(x, y, z)]
		if (c == c_lava or c == c_lava_flowing)
		and sulfur_noise:get3d({x = x, y = z, z = z}) >= 0.4 then
			for i in a:iter(
				math.max(minp.x, x - grid_size),
				math.max(minp.y, y - grid_size),
				math.max(minp.z, z - grid_size),
				math.min(maxp.x, x + grid_size),
				math.min(maxp.y, y + grid_size),
				math.min(maxp.z, z + grid_size)
			) do
				if data[i] == c_stone and pr:next(1, 10) <= 7 then
					data[i] = c_sulfur
				end
			end
		end
	end
	end
	end

	vm:set_data(data)
	vm:write_to_map(data)
end)


if technic.config:get_bool("enable_marble_generation") then
minetest.register_ore({
	ore_type       = "sheet",
	ore            = "technic:marble",
	wherein        = "default:stone",
	clust_scarcity = 1,
	clust_num_ores = 1,
	clust_size     = 3,
	y_min     = -31000,
	y_max     = -50,
	noise_threshold = 0.4,
	noise_params = {offset=0, scale=15, spread={x=150, y=150, z=150}, seed=23, octaves=3, persist=0.70}
})
end

if technic.config:get_bool("enable_granite_generation") then
minetest.register_ore({
	ore_type       = "sheet",
	ore            = "technic:granite",
	wherein        = "default:stone",
	clust_scarcity = 1,
	clust_num_ores = 1,
	clust_size     = 4,
	y_min     = -31000,
	y_max     = -150,
	noise_threshold = 0.4,
	noise_params = {offset=0, scale=15, spread={x=130, y=130, z=130}, seed=24, octaves=3, persist=0.70}
})
end