khanat-code-old/code/ryzom/common/data_common/r2/r2_misc.lua
2010-08-04 22:38:34 +02:00

313 lines
8.4 KiB
Lua

-- This file contains a set of miscellanous functions that don't fit in any other place
-- TODO nico : could be useful outside r2 -> export this
---------------
-- FUNCTIONS --
---------------
------------------------------------------------------------------------------------------------------------
-- equivalent of the ? : C operator, execpt that the 2 sides are evaluated before assignement
function select(cond, valueForTrue, valueForFalse)
if cond then
return valueForTrue
else
return valueForFalse
end
end
------------------------------------------------------------------------------------------------------------
-- execute a function for each key pair in a table
function forEach(table, fn)
local i, v = next(table,nil) -- get first index of "o" and its value
while i do
fn(i, v)
i, v = next(table,i) -- get next index and its value
end
end
------------------------------------------------------------------------------------------------------------
-- extension to table library : remove all content of a table without deleting the table object
function table.clear(tbl)
while next(tbl) do
tbl[next(tbl)] = nil
end
table.setn(tbl, 0)
end
------------------------------------------------------------------------------------------------------------
-- extension to table library : merge the content of two table remove the element, remove fields with duplicated keys (except for number)
function table.merge(tbl1, tbl2)
local k, v = next(tbl2)
while k do
if (type(k) == "number") then
table.insert(tbl1, v)
else
tbl1[k] = v
end
k, v = next(tbl2, k)
end
end
------------------------------------------------------------------------------------------------------------
-- Addtion to the string library : test wether a string match with the given pattern (returns true is so)
function string.match(str, pattern)
assert( type(str) == "string")
if (str == nil) then
debugInfo(debug.traceback())
assert(0)
end
local startPos, endPos = string.find(str, pattern)
if startPos == nil then return false end
return startPos == 1 and endPos == string.len(str)
end
------------------------------------------------------------------------------------------------------------
-- clone content of a table
function clone(t)
local new = {}
local i, v = next(t, nil)
while i do
if (type(v)=="table") then v= clone(v) end
new[i] = v
i, v = next(t, i)
end
return new
end
------------------------------------------------------------------------------------------------------------
-- Test if 2 values are equal
-- If values are table, then a member wise comparison is done
function isEqual(lhs, rhs)
if type(lhs) ~= type(rhs) then return false end
if type(lhs) == "table" then
local lk, lv = next(lhs) -- keys
local rk, rv = next(rhs) -- values
while lk and rk do
if not isEqual(lk, rk) then
return false
end
if not isEqual(lv, rv) then
return false
end
lk, lv = next(lhs, lk)
rk, rv = next(rhs, rk)
end
if lk ~= nil or rk ~= nil then
return false
-- not same table length
end
return true
else
return lhs == rhs
end
end
------------------------------------------------------------------------------------------------------------
-- Test if 2 values are equal
-- If values are table, then a member wise comparison is done
-- special : function pointer are ignored and considered equals
function isEqualIgnoreFunctions(lhs, rhs)
if type(lhs) ~= type(rhs) then return false end
if type(lhs) == "table" then
local lk, lv = next(lhs) -- keys
local rk, rv = next(rhs) -- values
while lk and rk do
if not isEqualIgnoreFunctions(lk, rk) then
return false
end
if not isEqualIgnoreFunctions(lv, rv) then
return false
end
lk, lv = next(lhs, lk)
rk, rv = next(rhs, rk)
end
if lk ~= nil or rk ~= nil then
return false
-- not same table length
end
return true
elseif type(lhs) == "function" then
return true
else
return lhs == rhs
end
end
------------------------------------------------------------------------------------------------------------
-- clone of a table, but with a depth of 1 ...
function shallowClone(t)
local new = {}
local i, v = next(t, nil)
while i do
new[i] = v
i, v = next(t, i)
end
return new
end
-------------------------------------------------------------------------------------------------
-- If args 'value' is nil then the arg 'default' is returned, else the actual 'value' is return
function defaulting(value, default)
if value == nil then
return default
else
return value
end
end
-------------------------------------------------------------------------------------------------
-- return clamped value. Min and/or max are ignotred if null
function clamp(value, min, max)
local result = value
if min then result = math.max(min, result) end
if max then result = math.min(max, result) end
return result
end
-------------------------------------------------------------------------------------------------
-- enclose a string by double quotes
function strify(str)
return [["]] .. tostring(str) .. [["]]
end
------------------------------------------------------------------------------------------------------------
-- snap a position to ground, returning the z snapped coordinate
function r2:snapZToGround(x, y)
local x1, y1, z1 = r2:snapPosToGround(x, y)
return z1
end
-------------------------------------------------------------------------------------------------
--
--built an ordered table from a table whose index are strings
--example :
--
--table =
--{
--"bar" = test(),
--"foo" = { "hello" },
--"abc" = 10,
--}
--
--result = sortAlphabeticaly(table)
--
--
--result is an integer indexed table :
--{
-- -- index = { sorted key, value }
-- 1 = { "abc", 10 },
-- 2 = { "bar", test() },
-- 3 = { "foo", { "hello" } }
--}
--
function sortAlphabetically(src)
local sortedTable = {}
local index = 1
for k, v in pairs(src) do
sortedTable[index] = { key = k, value = v }
index = index + 1
end
local function comp(val1, val2)
return val1.key < val2.key
end
table.sort(sortedTable, comp)
return sortedTable
end
----------
-- INIT --
----------
-- redefine the 'next' function of lua to use a "__next" function in the metatable
-- useful to traverse C++ objects that are exposed to lua through the use of the metatable
assert(next ~= nil) -- default lib should have been opened
if oldNextFunction == nil then
oldNextFunction = next
end
next = function(table, key)
assert(table)
local mt = getmetatable(table)
if mt ~= nil then
if mt.__next ~= nil then
return mt.__next(table, key)
end
end
-- tmp
--if type(table) ~= "table" then
-- debugInfo(debug.traceback())
-- debugInfo("'next' expect a table (or user data with __next metamethod) as its first parameter")
-- return
--end
-- else use default 'next' function
return oldNextFunction(table, key)
end
assert(table.getn ~= nil) -- default lib should have been opened
if oldTableGetnFunction == nil then
oldTableGetnFunction = table.getn
end
table.getn = function(table)
assert(table)
local mt = getmetatable(table)
if mt ~= nil then
if mt.__next ~= nil then
return table.Size
end
end
return oldTableGetnFunction(table)
end
-- redefine the hardcoded 'pairs' function to use the redefined 'next'
-- hardcoded version uses the C version of next, not the lua one if it has been redefined
if oldPairsFunction ~= nil then
pairs = oldPairsFunction
end
if oldPairsFunction == nil then
oldPairsFunction = pairs
end
if true then
-- TODO nico : bad init of editor if I name this 'pairs' directly (don't know why), so named it 'specPairs' and used
-- 'specPairs' when I must iterate over C++ objects ...
specPairs = function(table)
local function iterFunc(table, key)
return next(table, key)
end
return iterFunc, table
end
end
function r2.assert (param)
if not param then assert(nil) end
return param
end
function r2.isTable(node)
if not node then return false end
if type(node) == "table" then
return true
elseif type(node) == "userdata" then
local mt = getmetatable(node)
if mt~= nil and mt.__next ~= nil then
return true
end
end
return false
end