mapgen_rivers/pregenerate.lua
Gaël C 11e6e72324 Started refactoring code structure to support a separate mapgen thread
Probably not working for now (untested), still some things to do
Also making the code cleaner
2023-12-28 15:27:36 +01:00

113 lines
2.8 KiB
Lua

local EvolutionModel = dofile(mapgen_rivers.modpath .. '/terrainlib_lua/erosion.lua')
local twist = dofile(mapgen_rivers.modpath .. '/terrainlib_lua/twist.lua')
local blocksize = mapgen_rivers.settings.blocksize
local tectonic_speed = mapgen_rivers.settings.tectonic_speed
local np_base = table.copy(mapgen_rivers.noise_params.base)
local evol_params = mapgen_rivers.settings.evol_params
local time = mapgen_rivers.settings.evol_time
local time_step = mapgen_rivers.settings.evol_time_step
local niter = math.ceil(time/time_step)
time_step = time / niter
-- Setup the model
local grid = mapgen_rivers.grid
local size = grid.size
local seed = tonumber(minetest.get_mapgen_setting("seed"))
np_base.seed = (np_base.seed or 0) + seed
local nobj_base = PerlinNoiseMap(np_base, {x=size.x, y=1, z=size.y})
local dem = nobj_base:get_3d_map_flat({x=0, y=0, z=0})
dem.X = size.x
dem.Y = size.y
local model = EvolutionModel(evol_params)
model.dem = dem
local ref_dem = model:define_isostasy(dem)
local tectonic_step = tectonic_speed * time_step
collectgarbage()
-- Run the model
for i=1, niter do
minetest.log("info", "[mapgen_rivers] Iteration " .. i .. " of " .. niter)
model:diffuse(time_step)
model:flow()
model:erode(time_step)
if i < niter then
if tectonic_step ~= 0 then
nobj_base:get_3d_map_flat({x=0, y=tectonic_step*i, z=0}, ref_dem)
end
model:isostasy()
end
collectgarbage()
end
model:flow()
local mfloor = math.floor
local mmin, mmax = math.min, math.max
local offset_x, offset_y = twist(model.dirs, model.rivers, 5)
for i=1, size.x*size.y do
offset_x[i] = mmin(mmax(offset_x[i]*256, -128), 127)
offset_y[i] = mmin(mmax(offset_y[i]*256, -128), 127)
end
-- Write the results in the world directory
minetest.mkdir(mapgen_rivers.world_data_path)
local function write_map(filename, data, bytes)
local size = #data
local file = io.open(worldpath .. filename, 'wb')
local bytelist = {}
for j=1, bytes do
bytelist[j] = 0
end
local unpk = unpack
local schar = string.char
local floor = math.floor
for i=1, size do
local n = floor(data[i])
data[i] = n
for j=bytes, 2, -1 do
bytelist[j] = n % 256
n = floor(n / 256)
end
bytelist[1] = n % 256
file:write(schar(unpk(bytelist)))
end
file:close()
end
write_map('dem', model.dem, 2)
write_map('lakes', model.lakes, 2)
write_map('dirs', model.dirs, 1)
write_map('rivers', model.rivers, 4)
write_map('offset_x', offset_x, 1)
write_map('offset_y', offset_y, 1)
local sfile = io.open(mapgen_rivers.world_data_path .. 'size', "w")
sfile:write(size.x..'\n'..size.y)
sfile:close()
if not mapgen_rivers.settings.use_interactive_loader then
mapgen_rivers.grid = {
size = {x=size_x, y=size_y},
dem = model.dem,
lakes = model.lakes,
dirs = model.dirs,
rivers = model.rivers,
offset_x = offset_x,
offset_y = offset_y,
}
end