minetest/builtin/voxelarea.lua

104 lines
2.3 KiB
Lua

VoxelArea = {
MinEdge = {x=1, y=1, z=1},
MaxEdge = {x=0, y=0, z=0},
ystride = 0,
zstride = 0,
}
function VoxelArea:new(o)
o = o or {}
setmetatable(o, self)
self.__index = self
local e = o:getExtent()
o.ystride = e.x
o.zstride = e.x * e.y
return o
end
function VoxelArea:getExtent()
return {
x = self.MaxEdge.x - self.MinEdge.x + 1,
y = self.MaxEdge.y - self.MinEdge.y + 1,
z = self.MaxEdge.z - self.MinEdge.z + 1,
}
end
function VoxelArea:getVolume()
local e = self:getExtent()
return e.x * e.y * e.z
end
function VoxelArea:index(x, y, z)
local i = (z - self.MinEdge.z) * self.zstride +
(y - self.MinEdge.y) * self.ystride +
(x - self.MinEdge.x) + 1
return math.floor(i)
end
function VoxelArea:indexp(p)
local i = (p.z - self.MinEdge.z) * self.zstride +
(p.y - self.MinEdge.y) * self.ystride +
(p.x - self.MinEdge.x) + 1
return math.floor(i)
end
function VoxelArea:position(i)
local p = {}
i = i - 1
p.z = math.floor(i / self.zstride) + self.MinEdge.z
i = i % self.zstride
p.y = math.floor(i / self.ystride) + self.MinEdge.y
i = i % self.ystride
p.x = math.floor(i) + self.MinEdge.x
return p
end
function VoxelArea:contains(x, y, z)
return (x >= self.MinEdge.x) and (x <= self.MaxEdge.x) and
(y >= self.MinEdge.y) and (y <= self.MaxEdge.y) and
(z >= self.MinEdge.z) and (z <= self.MaxEdge.z)
end
function VoxelArea:containsp(p)
return (p.x >= self.MinEdge.x) and (p.x <= self.MaxEdge.x) and
(p.y >= self.MinEdge.y) and (p.y <= self.MaxEdge.y) and
(p.z >= self.MinEdge.z) and (p.z <= self.MaxEdge.z)
end
function VoxelArea:containsi(i)
return (i >= 1) and (i <= self:getVolume())
end
function VoxelArea:iter(minx, miny, minz, maxx, maxy, maxz)
local i = self:index(minx, miny, minz) - 1
local last = self:index(maxx, maxy, maxz)
local ystride = self.ystride
local zstride = self.zstride
local yoff = (last+1) % ystride
local zoff = (last+1) % zstride
local ystridediff = (i - last) % ystride
local zstridediff = (i - last) % zstride
return function()
i = i + 1
if i % zstride == zoff then
i = i + zstridediff
elseif i % ystride == yoff then
i = i + ystridediff
end
if i <= last then
return i
end
end
end
function VoxelArea:iterp(minp, maxp)
return self:iter(minp.x, minp.y, minp.z, maxp.x, maxp.y, maxp.z)
end