mirror of
https://github.com/sbrl/Minetest-WorldEditAdditions.git
synced 2024-09-12 08:08:30 +02:00
125 lines
4.7 KiB
Lua
125 lines
4.7 KiB
Lua
local wea = worldeditadditions
|
|
local wea_c = worldeditadditions_core
|
|
|
|
--- Parses a comma-separated side numbers list out into a list of numbers.
|
|
-- @param list string The command separated list to parse.
|
|
-- @returns number[] A list of side numbers.
|
|
local function parse_sides_list(list)
|
|
list = list:gsub("%s", "") -- Spaces are not permitted
|
|
return wea_c.table.unique(wea_c.table.map(
|
|
wea_c.split(list, ","),
|
|
function(value) return tonumber(value) end
|
|
))
|
|
end
|
|
|
|
function worldeditadditions.erode.river(heightmap_initial, heightmap, heightmap_size, region_height, params_custom)
|
|
local params = {
|
|
steps = 1, -- Number of rounds/passes of the algorithm to run
|
|
lower_sides = "4,3", -- Cells with this many adjacent horizontal neighbours that are lower than the current pixel will be removed
|
|
raise_sides = "4,3", -- Cells with this many adjacect horizontal neighbours that are higher than the current pixel will be filled in
|
|
doraise = true, -- Whether to do raise operations or not
|
|
dolower = true -- Whether to do lower operations or not
|
|
}
|
|
-- Apply the custom settings
|
|
wea_c.table.apply(params_custom, params)
|
|
|
|
params.lower_sides = parse_sides_list(params.lower_sides)
|
|
params.raise_sides = parse_sides_list(params.raise_sides)
|
|
|
|
local timings = {}
|
|
local filled = 0
|
|
local removed = 0
|
|
for i=1,params.steps do
|
|
-- print("[DEBUG:river] step ", i)
|
|
-- wea_c.format.array_2d(heightmap, heightmap_size.x)
|
|
local time_start = wea_c.get_ms_time()
|
|
|
|
-- Store up changes to make and make them at the end of the step
|
|
-- This is important, because decisions
|
|
local fill = { } -- Indexes to add 1 to
|
|
local remove = { } -- Indexes to take 1 away from
|
|
|
|
for z = heightmap_size.z - 1, 0, -1 do
|
|
for x = heightmap_size.x - 1, 0, -1 do
|
|
local hi = z*heightmap_size.x + x
|
|
local thisheight = heightmap[hi]
|
|
-- print("[DEBUG:river] z", z, "x", x, "thisheight", thisheight)
|
|
|
|
local height_up = heightmap[hi]
|
|
local height_down = heightmap[hi]
|
|
local height_left = heightmap[hi]
|
|
local height_right = heightmap[hi]
|
|
|
|
if x > 0 then height_left = heightmap[z*heightmap_size.x + x-1] end
|
|
if x < heightmap_size.x - 1 then height_right = heightmap[z*heightmap_size.x + x+1] end
|
|
if z > 0 then height_up = heightmap[(z-1)*heightmap_size.x + x] end
|
|
if z < heightmap_size.z - 1 then height_down = heightmap[(z+1)*heightmap_size.x + x] end
|
|
|
|
-- Whether this pixel is on the edge
|
|
local isedge = x <= 0
|
|
or z <= 0
|
|
or x >= heightmap_size.x - 1
|
|
or z >= heightmap_size.z - 1
|
|
|
|
local sides_higher = 0 -- Number of sides higher than this pixel
|
|
local sides_lower = 0 -- Number of sides lower than this pixel
|
|
if not isedge then
|
|
if height_down > thisheight then sides_higher = sides_higher + 1 end
|
|
if height_up > thisheight then sides_higher = sides_higher + 1 end
|
|
if height_left > thisheight then sides_higher = sides_higher + 1 end
|
|
if height_right > thisheight then sides_higher = sides_higher + 1 end
|
|
|
|
if height_down < thisheight then sides_lower = sides_lower + 1 end
|
|
if height_up < thisheight then sides_lower = sides_lower + 1 end
|
|
if height_left < thisheight then sides_lower = sides_lower + 1 end
|
|
if height_right < thisheight then sides_lower = sides_lower + 1 end
|
|
end
|
|
|
|
-- Perform an action, but only if we're not on the edge
|
|
-- This is important, as we can't accurately tell how many
|
|
-- adjacent neighbours a pixel on the edge has.
|
|
local action = "none"
|
|
if not isedge then
|
|
if sides_higher > sides_lower then
|
|
for _,sidecount in ipairs(params.raise_sides) do
|
|
if sidecount == sides_higher then
|
|
action = "fill"
|
|
break
|
|
end
|
|
end
|
|
else
|
|
for _i,sidecount in ipairs(params.lower_sides) do
|
|
if sidecount == sides_lower then
|
|
action = "remove"
|
|
break
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
|
|
if action == "fill" and params.doraise then
|
|
table.insert(fill, hi)
|
|
filled = filled + 1
|
|
elseif action == "remove" and params.dolower then
|
|
table.insert(remove, hi)
|
|
removed = removed + 1
|
|
end
|
|
-- print("[DEBUG:river] sides_higher", sides_higher, "sides_lower", sides_lower, "action", action)
|
|
-- wea_c.format.array_2d(heightmap, heightmap_size.x)
|
|
end
|
|
end
|
|
|
|
for _i,hi in ipairs(fill) do
|
|
heightmap[hi] = heightmap[hi] + 1
|
|
end
|
|
for _i,hi in ipairs(remove) do
|
|
heightmap[hi] = heightmap[hi] - 1
|
|
end
|
|
|
|
table.insert(timings, wea_c.get_ms_time() - time_start)
|
|
end
|
|
|
|
return true, params.steps.." steps made, raising "..filled.." and lowering "..removed.." columns in "..wea_c.format.human_time(wea_c.sum(timings)).." (~"..wea_c.format.human_time(wea_c.average(timings)).." per step)"
|
|
end
|