Minetest-WorldEditAdditions/worldeditadditions/lib/conv/convolution.lua
Starbeamrainbowlabs d96f169950
It works! :D
2020-06-10 00:48:39 +01:00

122 lines
4.4 KiB
Lua

worldeditadditions.conv = {}
dofile(worldeditadditions.modpath.."/lib/conv/kernels.lua")
dofile(worldeditadditions.modpath.."/lib/conv/kernel_gaussian.lua")
dofile(worldeditadditions.modpath.."/lib/conv/convolve.lua")
--- Creates a new kernel.
-- Note that the gaussian kernel only allows for creating a square kernel.
-- arg is only used by the gaussian kernel as the sigma value (default: 2)
-- @param name string The name of the kernel to create (possible values: box, pascal, gaussian).
-- @param width number The width of the kernel to create (must be an odd integer).
-- @param height number The height of the kernel to create (must be an odd integer).
-- @param arg number The argument to pass when creating the kernel. Currently only used by gaussian kernel as the sigma value.
function worldeditadditions.get_conv_kernel(name, width, height, arg)
if width % 2 ~= 1 then
return false, "Error: The width must be an odd integer.";
end
if height % 2 ~= 1 then
return false, "Error: The height must be an odd integer";
end
if name == "box" then
return true, worldeditadditions.conv.kernel_box(width, height)
elseif name == "pascal" then
return true, worldeditadditions.conv.kernel_pascal(width, height, true)
elseif name == "gaussian" then
if width ~= height then
return false, "Error: When using a gaussian kernel the width and height must be identical."
end
-- Default to sigma = 2
if arg == nil then arg = 2 end
local success, result = worldeditadditions.conv.kernel_gaussian(width, arg)
return success, result
end
return false, "Error: Unknown kernel. Valid values: box, pascal, gaussian"
end
function worldeditadditions.convolve(pos1, pos2, kernel, kernel_size)
pos1, pos2 = worldedit.sort_pos(pos1, pos2)
local border_size = {}
border_size[0] = (kernel_size[0]-1) / 2 -- height
border_size[1] = (kernel_size[1]-1) / 2 -- width
pos1.z = pos1.z - border_size[0]
pos2.z = pos2.z + border_size[0]
pos1.x = pos1.x - border_size[1]
pos2.x = pos2.x + border_size[1]
local manip, area = worldedit.manip_helpers.init(pos1, pos2)
local data = manip:get_data()
local stats = { added = 0, removed = 0 }
local node_id_air = minetest.get_content_id("air")
local heightmap = worldeditadditions.make_heightmap(pos1, pos2, manip, area, data)
local heightmap_conv = worldeditadditions.shallowcopy(heightmap)
local heightmap_size = {}
heightmap_size[0] = (pos2.z - pos1.z) + 1
heightmap_size[1] = (pos2.x - pos1.x) + 1
worldeditadditions.conv.convolve(
heightmap_conv,
heightmap_size,
kernel,
kernel_size
)
-- print("original")
-- worldeditadditions.print_2d(heightmap, (pos2.z - pos1.z) + 1)
-- print("transformed")
-- worldeditadditions.print_2d(heightmap_conv, (pos2.z - pos1.z) + 1)
-- It seems to be convolving as intended, but something's probably getting lost in translation below
for z = heightmap_size[0], 0, -1 do
for x = heightmap_size[1], 0, -1 do
local hi = z*heightmap_size[1] + x
local height_old = heightmap[hi]
local height_new = heightmap_conv[hi]
-- print("[conv/save] hi", hi, "height_old", heightmap[hi], "height_new", heightmap_conv[hi], "z", z, "x", x, "pos1.y", pos1.y)
-- Lua doesn't have a continue statement :-/
if height_old == height_new then
-- noop
elseif height_new < height_old then
stats.removed = stats.removed + (height_old - height_new)
local y = height_new
while y < height_old do
local ci = area:index(pos1.x + x, pos1.y + y, pos1.z + z)
-- print("[conv/save] remove at y", y, "→", pos1.y + y, "current:", minetest.get_name_from_content_id(data[ci]))
data[ci] = node_id_air
y = y + 1
end
else -- height_new > height_old
-- We subtract one because the heightmap starts at 1 (i.e. 1 = 1 node in the column), but the selected region is inclusive
local node_id = data[area:index(pos1.x + x, pos1.y + (height_old - 1), pos1.z + z)]
-- print("[conv/save] filling with ", node_id, "→", minetest.get_name_from_content_id(node_id))
stats.added = stats.added + (height_new - height_old)
local y = height_old
while y < height_new do
local ci = area:index(pos1.x + x, pos1.y + y, pos1.z + z)
-- print("[conv/save] add at y", y, "→", pos1.y + y, "current:", minetest.get_name_from_content_id(data[ci]))
data[ci] = node_id
y = y + 1
end
end
end
end
worldedit.manip_helpers.finish(manip, data)
return true, stats
end