Built-ins API documentation

hash

hash = userdata

Defold represents resource paths, message names, object ids, and many other identifiers as 64-bit hash values. Create one from a string with hash, or receive one from an engine API. Hashes can be compared for equality and used as table keys, but the original string is not generally recoverable in release builds.

EXAMPLES

local damage_message = hash("take_damage")

function on_message(self, message_id, message, sender)
    if message_id == damage_message then
        self.health = self.health - message.amount
    end
end

script_instance

script_instance = userdata

An engine-created state container passed as self to script lifecycle functions and callbacks. Each script component, GUI script, and render script has its own instance. Values assigned to the instance remain available for that instance's lifetime. Script instances cannot be created directly. Store state by assigning fields to the self value supplied by the engine.

EXAMPLES

function init(self)
    self.health = 100

    timer.delay(1, false, function(self, handle, time_elapsed)
        self.health = self.health - 10
        print(self.health)
    end)
end

hash()

hash(s:string)→hash:hash

All ids in the engine are represented as hashes, so a string needs to be hashed before it can be compared with an id.

PARAMETERS

RETURNS

EXAMPLES

function on_message(self, message_id, message, sender)
    if message_id == hash("my_message") then
        -- Act on the message here
    end
end

hash_to_hex()

hash_to_hex(h:hash)→hex:string

Returns a hexadecimal representation of a hash value. The returned string is always padded with leading zeros.

PARAMETERS

RETURNS

EXAMPLES

local h = hash("my_hash")
local hexstr = hash_to_hex(h)
print(hexstr) --> a2bc06d97f580aab

pprint()

pprint(...:any)

Pretty printing of Lua values. This function prints Lua values in a manner similar to +print()+, but will also recurse into tables and pretty print them. There is a limit to how deep the function will recurse.

PARAMETERS

EXAMPLES

local t2 = { 1, 2, 3, 4 }
local t = { key = "value", key2 = 1234, key3 = t2 }
pprint(t)

{
  key3 = {
    1 = 1,
    2 = 2,
    3 = 3,
    4 = 4,
  }
  key2 = 1234,
  key = value,
}