Add voxelarea.lua helper to builtin

This commit is contained in:
kwolekr 2013-06-28 10:28:15 -04:00
parent 280946ba83
commit 3f13dc790c
3 changed files with 57 additions and 1 deletions

@ -25,4 +25,4 @@ dofile(minetest.get_modpath("__builtin").."/static_spawn.lua")
dofile(minetest.get_modpath("__builtin").."/detached_inventory.lua")
dofile(minetest.get_modpath("__builtin").."/falling.lua")
dofile(minetest.get_modpath("__builtin").."/features.lua")
dofile(minetest.get_modpath("__builtin").."/voxelarea.lua")

46
builtin/voxelarea.lua Normal file

@ -0,0 +1,46 @@
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

@ -1572,6 +1572,16 @@ methods:
^ will be ignored
- update_liquids(): Update liquid flow
VoxelArea: A helper class for voxel areas
- Can be created via VoxelArea:new{MinEdge=pmin, MaxEdge=pmax}
- Coordinates are *inclusive*, like most other things in Minetest
methods:
- getExtent(): returns a 3d vector containing the size of the area formed by MinEdge and MaxEdge
- getVolume(): returns the volume of the area formed by MinEdge and MaxEdge
- index(x, y, z): returns the index of an absolute position in a flat array starting at 1
^ useful for things like VoxelManip, raw Schematic specifiers, PerlinNoiseMap:get2d/3dMap, and so on
- indexp(p): same as above, except takes a vector
Mapgen objects
---------------
A mapgen object is a construct used in map generation. Mapgen objects can be used by an on_generate