techage/basis/gravel_lib.lua
2023-04-16 15:07:29 +02:00

103 lines
3.0 KiB
Lua

--[[
TechAge
=======
Copyright (C) 2019 Joachim Stolberg
AGPL v3
See LICENSE.txt for more information
Gravel Sieve basis functions
]]--
-- Increase the probability over the natural occurrence
local PROBABILITY_FACTOR = 2
-- Ore probability table (1/n)
local ore_probability = {
}
local ProbabilityCorrections = {
["default:tin_lump"] = 0.3, -- extensively used
["default:coal_lump"] = 0.2, -- extensively used
["default:iron_lump"] = 0.5, -- extensively used
["techage:baborium_lump"] = 99999, -- mining required
}
-- collect all registered ores and calculate the probability
local function add_ores()
for _,item in pairs(minetest.registered_ores) do
if not ore_probability[item.ore] and minetest.registered_nodes[item.ore] then
local drop = minetest.registered_nodes[item.ore].drop
if type(drop) == "string"
and drop ~= item.ore
and drop ~= ""
and item.ore_type == "scatter"
and item.wherein == "default:stone"
and item.clust_scarcity ~= nil and item.clust_scarcity > 0
and item.clust_num_ores ~= nil and item.clust_num_ores > 0
and item.y_max ~= nil and item.y_min ~= nil then
local factor = 0.5
if item.y_max < -250 then
factor = -250 / item.y_max
end
local probability = (techage.ore_rarity / PROBABILITY_FACTOR) * item.clust_scarcity /
(item.clust_num_ores * factor)
-- lower value means higher probability
ore_probability[drop] = math.min(ore_probability[drop] or 100000, probability)
end
end
end
-- some corrections
for key, correction in pairs(ProbabilityCorrections) do
if ore_probability[key] then
ore_probability[key] = ore_probability[key] * correction
-- consider upper and lower level
ore_probability[key] = techage.in_range(ore_probability[key], 10, 100000)
end
end
local overall_probability = 0.0
for name,probability in pairs(ore_probability) do
minetest.log("info", string.format("[techage] %-32s %u", name, probability))
overall_probability = overall_probability + 1.0/probability
end
minetest.log("info", string.format("[techage] Overall probability %g", overall_probability))
end
minetest.register_on_mods_loaded(add_ores)
--
-- Change the probability of ores or register new ores for sieving
--
function techage.register_ore_for_gravelsieve(ore_name, probability)
ore_probability[ore_name] = probability
end
-- determine ore based on the calculated probability
function techage.gravelsieve_get_random_gravel_ore()
for ore, probability in pairs(ore_probability) do
if math.random(probability) == 1 then
return ItemStack(ore)
end
end
if math.random(2) == 1 then
return ItemStack("default:gravel")
else
return ItemStack("techage:sieved_gravel")
end
end
function techage.gravelsieve_get_random_basalt_ore()
if math.random(40) == 1 then
return ItemStack("default:coal_lump")
elseif math.random(40) == 1 then
return ItemStack("default:iron_lump")
elseif math.random(2) == 1 then
return ItemStack("techage:basalt_gravel")
else
return ItemStack("techage:sieved_basalt_gravel")
end
end