diff options
| -rw-r--r-- | builtin/builtin.lua | 32 | ||||
| -rw-r--r-- | builtin/misc.lua | 10 | ||||
| -rw-r--r-- | builtin/vector.lua | 136 | ||||
| -rw-r--r-- | doc/lua_api.txt | 29 |
4 files changed, 192 insertions, 15 deletions
diff --git a/builtin/builtin.lua b/builtin/builtin.lua index d573cba90..34477e6aa 100644 --- a/builtin/builtin.lua +++ b/builtin/builtin.lua @@ -11,18 +11,20 @@ math.randomseed(os.time()) os.setlocale("C", "numeric") -- Load other files -dofile(minetest.get_modpath("__builtin").."/serialize.lua") -dofile(minetest.get_modpath("__builtin").."/misc_helpers.lua") -dofile(minetest.get_modpath("__builtin").."/item.lua") -dofile(minetest.get_modpath("__builtin").."/misc_register.lua") -dofile(minetest.get_modpath("__builtin").."/item_entity.lua") -dofile(minetest.get_modpath("__builtin").."/deprecated.lua") -dofile(minetest.get_modpath("__builtin").."/misc.lua") -dofile(minetest.get_modpath("__builtin").."/privileges.lua") -dofile(minetest.get_modpath("__builtin").."/auth.lua") -dofile(minetest.get_modpath("__builtin").."/chatcommands.lua") -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") +local modpath = minetest.get_modpath("__builtin") +dofile(modpath.."/serialize.lua") +dofile(modpath.."/misc_helpers.lua") +dofile(modpath.."/item.lua") +dofile(modpath.."/misc_register.lua") +dofile(modpath.."/item_entity.lua") +dofile(modpath.."/deprecated.lua") +dofile(modpath.."/misc.lua") +dofile(modpath.."/privileges.lua") +dofile(modpath.."/auth.lua") +dofile(modpath.."/chatcommands.lua") +dofile(modpath.."/static_spawn.lua") +dofile(modpath.."/detached_inventory.lua") +dofile(modpath.."/falling.lua") +dofile(modpath.."/features.lua") +dofile(modpath.."/voxelarea.lua") +dofile(modpath.."/vector.lua") diff --git a/builtin/misc.lua b/builtin/misc.lua index f4e7dbca6..4be03c38a 100644 --- a/builtin/misc.lua +++ b/builtin/misc.lua @@ -106,3 +106,13 @@ function minetest.formspec_escape(str) return str end +function math.hypot(x, y) + local t + x = math.abs(x) + y = math.abs(y) + t = math.min(x, y) + x = math.max(x, y) + t = t / x + return x * math.sqrt(1 + t * t) +end + diff --git a/builtin/vector.lua b/builtin/vector.lua new file mode 100644 index 000000000..f534471c2 --- /dev/null +++ b/builtin/vector.lua @@ -0,0 +1,136 @@ + +vector = {} + +function vector.new(a, b, c) + v = {x=0, y=0, z=0} + if type(a) == "table" then + v = {x=a.x, y=a.y, z=a.z} + elseif a and b and c then + v = {x=a, y=b, z=c} + end + setmetatable(v, { + __add = vector.add, + __sub = vector.subtract, + __mul = vector.multiply, + __div = vector.divide, + __umn = function(v) return vector.multiply(v, -1) end, + __len = vector.length, + __eq = vector.equals, + }) + return v +end + +function vector.equals(a, b) + return a.x == b.x and + a.y == b.y and + a.z == b.z +end + +function vector.length(v) + return math.hypot(v.x, math.hypot(v.y, v.z)) +end + +function vector.normalize(v) + return vector.divide(v, vector.length(v)) +end + +function vector.round(v) + return { + x = math.floor(v.x + 0.5), + y = math.floor(v.y + 0.5), + z = math.floor(v.z + 0.5) + } +end + +function vector.distance(a, b) + local x = a.x - b.x + local y = a.y - b.y + local z = a.z - b.z + return math.hypot(x, math.hypot(y, z)) +end + +function vector.direction(pos1, pos2) + local x_raw = pos2.x - pos1.x + local y_raw = pos2.y - pos1.y + local z_raw = pos2.z - pos1.z + local x_abs = math.abs(x_raw) + local y_abs = math.abs(y_raw) + local z_abs = math.abs(z_raw) + if x_abs >= y_abs and + x_abs >= z_abs then + y_raw = y_raw * (1 / x_abs) + z_raw = z_raw * (1 / x_abs) + x_raw = x_raw / x_abs + end + if y_abs >= x_abs and + y_abs >= z_abs then + x_raw = x_raw * (1 / y_abs) + z_raw = z_raw * (1 / y_abs) + y_raw = y_raw / y_abs + end + if z_abs >= y_abs and + z_abs >= x_abs then + x_raw = x_raw * (1 / z_abs) + y_raw = y_raw * (1 / z_abs) + z_raw = z_raw / z_abs + end + return {x=x_raw, y=y_raw, z=z_raw} +end + + +function vector.add(a, b) + if type(b) == "table" then + return vector.new( + a.x + b.x, + a.y + b.y, + a.z + b.z) + else + return vector.new( + a.x + b, + a.y + b, + a.z + b) + end +end + +function vector.subtract(a, b) + if type(b) == "table" then + return vector.new( + a.x - b.x, + a.y - b.y, + a.z - b.z) + else + return vector.new( + a.x - b, + a.y - b, + a.z - b) + end +end + +function vector.multiply(a, b) + if type(b) == "table" then + return vector.new( + a.x * b.x, + a.y * b.y, + a.z * b.z) + else + return vector.new( + a.x * b, + a.y * b, + a.z * b) + end +end + +function vector.divide(a, b) + if type(b) == "table" then + return vector.new( + a.x / b.x, + a.y / b.y, + a.z / b.z) + else + return vector.new( + a.x / b, + a.y / b, + a.z / b) + end +end + diff --git a/doc/lua_api.txt b/doc/lua_api.txt index a9f2d0d46..5a2fdf102 100644 --- a/doc/lua_api.txt +++ b/doc/lua_api.txt @@ -988,12 +988,41 @@ Inventory location: - "nodemeta:<X>,<Y>,<Z>": Any node metadata - "detached:<name>": A detached inventory +Vector helpers +--------------- +vector.new([x[, y, z]]) -> vector + ^ x is a table or the x position. +vector.direction(p1, p2) -> vector +vector.distance(p1, p2) -> number +vector.length(v) -> number +vector.normalize(v) -> vector +vector.round(v) -> vector +vector.equal(v1, v2) -> bool +vector.add(v, x) -> vector + ^ x can be annother vector or a number +vector.subtract(v, x) -> vector +vector.multiply(v, x) -> vector +vector.divide(v, x) -> vector + +You can also use Lua operators on vectors. +For example: + v1 = vector.new() + v1 = v1 + 5 + v2 = vector.new(v1) + v1 = v1 * v2 + if v1 == v2 then + error("Math broke") + end + Helper functions ----------------- dump2(obj, name="_", dumped={}) ^ Return object serialized as a string, handles reference loops dump(obj, dumped={}) ^ Return object serialized as a string +math.hypot(x, y) +^ Get the hypotenuse of a triangle with legs x and y. + Usefull for distance calculation. string:split(separator) ^ eg. string:split("a,b", ",") == {"a","b"} string:trim() |