mapgen_helper/noise_manager.lua

114 lines
4.0 KiB
Lua

local perlin_buffers = {}
mapgen_helper.register_perlin = function(name, perlin_params)
perlin_buffers[name] = perlin_buffers[name] or {}
if perlin_buffers[name].perlin_params then
minetest.log("error", "mapgen_helper.register_perlin3d called for " .. name .. " when perlin parameters were already registered.")
return
end
perlin_buffers[name].perlin_params = perlin_params
end
local get_buffer = function(name, sidelen, perlin_params)
perlin_buffers[name] = perlin_buffers[name] or {}
local buffer = perlin_buffers[name]
if buffer.sidelen ~= nil and buffer.sidelen ~= sidelen then
buffer.nobj_perlin = nil -- parameter changed, force regenerate of object
end
buffer.sidelen = sidelen
if perlin_params then
if buffer.perlin_params then
for k, v in pairs(buffer.perlin_params) do
if perlin_params[k] ~= v then
buffer.nobj_perlin = nil -- parameter changed, force regenerate of object
end
end
end
buffer.perlin_params = perlin_params -- record provided parameters
elseif buffer.perlin_params == nil then
minetest.log("error", "mapgen_helper.register_perlin3d called for " .. name .. " with no registered or provided perlin parameters.")
return
else
perlin_params = buffer.perlin_params -- retrieve recorded parameters
end
buffer.last_used = minetest.get_gametime()
return buffer, perlin_params
end
mapgen_helper.perlin3d = function(name, minp, maxp, perlin_params)
local minx = minp.x
local minz = minp.z
local sidelen = maxp.x - minp.x + 1 --length of a mapblock
local chunk_lengths = {x = sidelen, y = sidelen, z = sidelen} --table of chunk edges
local buffer, perlin_params = get_buffer(name, sidelen, perlin_params)
buffer.nvals_perlin_buffer = buffer.nvals_perlin_buffer or {}
buffer.nobj_perlin = buffer.nobj_perlin or minetest.get_perlin_map(perlin_params, chunk_lengths)
if buffer.nobj_perlin.get_3d_map_flat then
return buffer.nobj_perlin:get_3d_map_flat(minp, buffer.nvals_perlin_buffer), VoxelArea:new{MinEdge=minp, MaxEdge=maxp}
else
return buffer.nobj_perlin:get3dMap_flat(minp, buffer.nvals_perlin_buffer), VoxelArea:new{MinEdge=minp, MaxEdge=maxp}
end
end
mapgen_helper.perlin2d = function(name, minp, maxp, perlin_params)
local minx = minp.x
local minz = minp.z
local sidelen = maxp.x - minp.x + 1 --length of a mapblock
local chunk_lengths = {x = sidelen, y = sidelen, z = sidelen} --table of chunk edges
local buffer, perlin_params = get_buffer(name, sidelen, perlin_params)
buffer.nvals_perlin_buffer = perlin_buffers[name].nvals_perlin_buffer or {}
buffer.nobj_perlin = perlin_buffers[name].nobj_perlin or minetest.get_perlin_map(perlin_params, chunk_lengths)
if buffer.nobj_perlin.get_2d_map_flat then
return buffer.nobj_perlin:get_2d_map_flat({x=minp.x, y=minp.z}, perlin_buffers[name].nvals_perlin_buffer)
else
return buffer.nobj_perlin:get2dMap_flat({x=minp.x, y=minp.z}, perlin_buffers[name].nvals_perlin_buffer)
end
end
mapgen_helper.index2d = function(minp, maxp, x, z)
return x - minp.x +
(maxp.x - minp.x + 1) -- sidelen
*(z - minp.z)
+ 1
end
mapgen_helper.index2dp = function(minp, maxp, pos)
return mapgen_helper.index2d(minp, maxp, pos.x, pos.z)
end
-- Takes an index into a 3D area and returns the corresponding 2D index
-- assumes equal edge lengths
mapgen_helper.index2di = function(minp, maxp, area, vi)
local MinEdge = area.MinEdge
local zstride = area.zstride
local minpx = minp.x
local i = vi - 1
local z = math.floor(i / zstride) + MinEdge.z
local x = math.floor((i % zstride) % area.ystride) + MinEdge.x
return x - minpx +
(maxp.x - minpx + 1) -- sidelen
*(z - minp.z)
+ 1
end
-- If a noise buffer hasn't been used in 60 seconds, let garbage collection take it.
local time_elapsed = 0
minetest.register_globalstep(function(dtime)
time_elapsed = time_elapsed + dtime
if time_elapsed > 60 then
local current_time = minetest.get_gametime()
time_elapsed = 0
for _, buffer in pairs(perlin_buffers) do
if current_time - buffer.last_used > 60 then
buffer.nvals_perlin_buffer = nil
end
end
end
end)