VoxeLibre/mods/CORE/biomeinfo/init.lua
2020-04-03 12:50:48 +02:00

212 lines
5.1 KiB
Lua

biomeinfo = {}
-- Copied from mapgen_v6.h
local MGV6_FREQ_HOT = 0.4
local MGV6_FREQ_SNOW = -0.4
local MGV6_FREQ_TAIGA = 0.5
local MGV6_FREQ_JUNGLE = 0.5
-- Biome types
local BT_NORMAL = "Normal"
local BT_TUNDRA = "Tundra"
local BT_TAIGA = "Taiga"
local BT_DESERT = "Desert"
local BT_JUNGLE = "Jungle"
-- Get mapgen settings
local seed = tonumber(minetest.get_mapgen_setting("seed")) or 0
local mgv6_perlin_biome, mgv6_perlin_humidity, mgv6_np_biome
-- v6 default noiseparams are hardcoded here because Minetest doesn't give us those
local mgv6_np_biome_default = {
offset = 0,
scale = 1,
spread = { x = 500, y = 500, z = 500},
seed = 9130,
octaves = 3,
persistence = 0.50,
lacunarity = 2.0,
flags = "eased",
}
local mgv6_np_humidity_default = {
offset = 0.5,
scale = 0.5,
spread = { x = 500, y = 500, z = 500},
seed = 72384,
octaves = 3,
persistence = 0.50,
lacunarity = 2.0,
flags = "eased",
}
local v6_flags_str = minetest.get_mapgen_setting("mgv6_spflags")
if v6_flags_str == nil then
v6_flags_str = ""
end
local v6_flags = string.split(v6_flags_str)
local v6_use_snow_biomes = true
local v6_use_jungles = true
-- TODO: Implement biome blend.
-- Currently we pretend biome blend is disabled.
-- This just makes the calculations inaccurate near biome boundaries,
-- but should be fine otherwise.
local v6_use_biome_blend = false
for f=1, #v6_flags do
local flag = v6_flags[f]:trim()
if flag == "nosnowbiomes" then
v6_use_snow_biomes = false
end
if flag == "snowbiomes" then
v6_use_snow_biomes = true
end
if flag == "nojungles" then
v6_use_jungles = false
end
if flag == "jungles" then
v6_use_jungles = true
end
if flag == "nobiomeblend" then
v6_use_biome_blend = false
end
-- TODO
-- if flag == "biomeblend" then
-- v6_use_biome_blend = true
-- end
end
-- Force-enable jungles when snowbiomes flag is set
if v6_use_snow_biomes then
v6_use_jungles = true
end
local v6_freq_desert = tonumber(minetest.get_mapgen_setting("mgv6_freq_desert") or 0.45)
local NOISE_MAGIC_X = 1619
local NOISE_MAGIC_Y = 31337
local NOISE_MAGIC_Z = 52591
local NOISE_MAGIC_SEED = 1013
local noise2d = function(x, y, seed)
-- TODO: implement noise2d function for biome blend
return 0
--[[
local n = (NOISE_MAGIC_X * x + NOISE_MAGIC_Y * y
+ NOISE_MAGIC_SEED * seed) & 0x7fffffff;
n = (n >> 13) ^ n;
n = (n * (n * n * 60493 + 19990303) + 1376312589) & 0x7fffffff;
return 1.0 - n / 0x40000000;
]]
end
biomeinfo.all_v6_biomes = {
BT_NORMAL,
BT_DESERT,
BT_JUNGLE,
BT_TUNDRA,
BT_TAIGA
}
local function init_perlins()
if not mgv6_perlin_biome then
mgv6_np_biome = minetest.get_mapgen_setting_noiseparams("mgv6_np_biome")
if not mgv6_np_biome then
mgv6_np_biome = mgv6_np_biome_default
minetest.log("action", "[biomeinfo] Using hardcoded mgv6_np_biome default")
end
mgv6_perlin_biome = minetest.get_perlin(mgv6_np_biome)
end
if not mgv6_perlin_humidity then
local np_humidity = minetest.get_mapgen_setting_noiseparams("mgv6_np_humidity")
if not np_humidity then
np_humidity = mgv6_np_humidity_default
minetest.log("action", "[biomeinfo] Using hardcoded mgv6_np_humidity default")
end
mgv6_perlin_humidity = minetest.get_perlin(np_humidity)
end
end
function biomeinfo.get_active_v6_biomes()
local biomes = { BT_NORMAL, BT_DESERT }
if v6_use_jungles then
table.insert(biomes, BT_JUNGLE)
end
if v6_use_snow_biomes then
table.insert(biomes, BT_TUNDRA)
table.insert(biomes, BT_TAIGA)
end
return biomes
end
function biomeinfo.get_v6_heat(pos)
init_perlins()
if not mgv6_perlin_biome then
return nil
end
local bpos = vector.floor(pos)
-- The temperature noise needs a special offset (see calculateNoise in mapgen_v6.cpp)
return mgv6_perlin_biome:get_2d({x=bpos.x + mgv6_np_biome.spread.x*0.6, y=bpos.z + mgv6_np_biome.spread.z*0.2})
end
function biomeinfo.get_v6_humidity(pos)
init_perlins()
if not mgv6_perlin_humidity then
return nil
end
local bpos = vector.floor(pos)
return mgv6_perlin_humidity:get_2d({x=bpos.x, y=bpos.z})
end
-- Returns the v6 biome at pos.
-- Returns a string representing the biome name.
function biomeinfo.get_v6_biome(pos)
init_perlins()
local bpos = vector.floor(pos)
-- Based on the algorithm MapgenV6::getBiome in mapgen_v6.cpp
local pos2d = {x=bpos.x, y=bpos.z}
if not mgv6_perlin_biome or not mgv6_perlin_humidity then
return "???"
end
local d = biomeinfo.get_v6_heat(bpos)
local h = biomeinfo.get_v6_humidity(bpos)
if (v6_use_snow_biomes) then
local blend
if v6_use_biome_blend then
blend = noise2d(pos2d.x, pos2d.y, seed) / 40
else
blend = 0
end
if (d > MGV6_FREQ_HOT + blend) then
if (h > MGV6_FREQ_JUNGLE + blend) then
return BT_JUNGLE
end
return BT_DESERT
end
if (d < MGV6_FREQ_SNOW + blend) then
if (h > MGV6_FREQ_TAIGA + blend) then
return BT_TAIGA
end
return BT_TUNDRA
end
return BT_NORMAL
end
if (d > v6_freq_desert) then
return BT_DESERT
end
if ((v6_use_biome_blend) and (d > v6_freq_desert - 0.10) and
((noise2d(pos2d.x, pos2d.y, seed) + 1.0) > (v6_freq_desert - d) * 20.0)) then
return BT_DESERT
end
if ((v6_use_jungles) and (h > 0.75)) then
return BT_JUNGLE
end
return BT_NORMAL
end