| commit | author | age | ||
| d78126 | 1 | -- A simple special-purpose class, this is used for building up sets of three-dimensional points for fast reference |
| CM | 2 | |
| 3 | Pointset = {} | |
| 4 | Pointset.__index = Pointset | |
| 5 | ||
| 6 | function Pointset.create() | |
| 7 | local set = {} | |
| 8 | setmetatable(set,Pointset) | |
| 9 | set.points = {} | |
| 10 | return set | |
| 11 | end | |
| 12 | ||
| 13 | function Pointset:set(x, y, z, value) | |
| 14 | -- sets a value in the 3D array "points". | |
| 15 | if self.points[x] == nil then | |
| 16 | self.points[x] = {} | |
| 17 | end | |
| 18 | if self.points[x][y] == nil then | |
| 19 | self.points[x][y] = {} | |
| 20 | end | |
| 21 | self.points[x][y][z] = value | |
| 22 | end | |
| 23 | ||
| 24 | function Pointset:set_if_not_in(excluded, x, y, z, value) | |
| 25 | -- If a value is not already set for this point in the 3D array "excluded", set it in "points" | |
| 26 | if excluded:get(x, y, z) ~= nil then | |
| 27 | return | |
| 28 | end | |
| 29 | self:set(x, y, z, value) | |
| 30 | end | |
| 31 | ||
| 32 | function Pointset:get(x, y, z) | |
| 33 | -- return a value from the 3D array "points" | |
| 34 | if self.points[x] == nil or self.points[x][y] == nil then | |
| 35 | return nil | |
| 36 | end | |
| 37 | return self.points[x][y][z] | |
| 38 | end | |
| 39 | ||
| 40 | function Pointset:set_pos(pos, value) | |
| 41 | self:set(pos.x, pos.y, pos.z, value) | |
| 42 | end | |
| 43 | ||
| 44 | function Pointset:set_pos_if_not_in(excluded, pos, value) | |
| 45 | self:set_if_not_in(excluded, pos.x, pos.y, pos.z, value) | |
| 46 | end | |
| 47 | ||
| 48 | function Pointset:get_pos(pos) | |
| 49 | return self:get(pos.x, pos.y, pos.z) | |
| 50 | end | |
| 51 | ||
| 52 | function Pointset:pop() | |
| 53 | -- returns a point that's in the 3D array, and then removes it. | |
| 54 | local pos = {} | |
| 55 | local ytable | |
| 56 | local ztable | |
| 57 | local val | |
| 58 | ||
| 59 | local count = 0 | |
| 60 | for _ in pairs(self.points) do count = count + 1 end | |
| 61 | if count == 0 then | |
| 62 | return nil | |
| 63 | end | |
| 64 | ||
| 65 | pos.x, ytable = next(self.points) | |
| 66 | pos.y, ztable = next(ytable) | |
| 67 | pos.z, val = next(ztable) | |
| 68 | ||
| 69 | self.points[pos.x][pos.y][pos.z] = nil | |
| 70 | ||
| 71 | count = 0 | |
| 72 | for _ in pairs(self.points[pos.x][pos.y]) do count = count + 1 end | |
| 73 | if count == 0 then | |
| 74 | self.points[pos.x][pos.y] = nil | |
| 75 | end | |
| 76 | ||
| 77 | count = 0 | |
| 78 | for _ in pairs(self.points[pos.x]) do count = count + 1 end | |
| 79 | if count == 0 then | |
| 80 | self.points[pos.x] = nil | |
| 81 | end | |
| 82 | ||
| 83 | return pos, val | |
| 84 | end | |
| 85 | ||
| 86 | function Pointset:get_pos_list(value) | |
| 87 | -- Returns a list of all points with the given value in standard Minetest vector format. If no value is provided, returns all points | |
| 88 | local outlist = {} | |
| 89 | for x, ytable in ipairs(self.points) do | |
| 90 | for y, ztable in ipairs(ytable) do | |
| 91 | for z, val in ipairs(ztable) do | |
| 92 | if (value == nil and val ~= nil ) or val == value then | |
| 93 | table.insert(outlist, {x=x, y=y, z=z}) | |
| 94 | end | |
| 95 | end | |
| 96 | end | |
| 97 | end | |
| 98 | return outlist | |
| 99 | end | |
