LUA Scripts do not stay after script "Save and Play"

[manticorp]

Hey! First of all, thanks for the awesome library - I've been using it to load a card game on TTS and it is great so far!

When using Decker to create a deck of cards with a different LUA script on each card, upon doing any other scripting and using the "Save & Play" button in TTS, all objects then get the same script.

To reproduce, use the following script (including Decker at the top):

function reimportCards()
    local cardFaces = 'https://i.imgur.com/wiyVst7.png'
    local cardBack = 'https://i.imgur.com/KQtQGE7.png'

    local cardAsset = Decker.Asset(cardFaces, cardBack, {width = 2, height = 2})

    local cardOne = Decker.Card(cardAsset, 1, 1, {
        Nickname = 'Card A',
        LuaScript = 'card = "A"'
    })

    local cardTwo = Decker.Card(cardAsset, 1, 2, {
        Nickname = 'Card B',
        LuaScript = 'card = "B"'
    })

    local myDeck = Decker.Deck({cardOne, cardTwo})
    myDeck:spawn({position = {0, 3, -6}})
end

function debugCards()
    log('Debugging Cards')
    broadcastToAll('Debugging Cards')
    AllObjectsOnTable = getObjects()
    for k,v in pairs(AllObjectsOnTable) do  --go through all Objects
        if (v.type == "Card") then
            log(v)
            log(v.getName())
            log(v.getVar('card'))
            broadcastToAll('Name: ' .. v.getName() .. ', card: ' .. v.getVar('card'))
        end
    end
end

function onChat(message)
    if message == "reimportCards"
    then
        reimportCards()
    elseif message == "debugCards"
    then
        debugCards()
    end
end

then, without doing anything else, save the game.

Now, reload the game and check the cards - they should have the correct variables in the lua scripts.

Now, reload the game up, and before doing anything, click "Save & Play" in the script editor.

Now check the cards, the Lua scripts will both read card = "A"

It is expected that the cards would read card = "A" and card = "B"

[manticorp]

I believe this has to do with every object being given the same GUID on creation:

-- Create a new CustomDeck asset
function Decker.Asset(face, back, options)
    local asset = {}
    options = options or {}
    asset.data = {
        FaceURL = face or error('Decker.Asset: faceImg link required'),
        BackURL = back or error('Decker.Asset: backImg link required'),
        NumWidth = options.width or 1,
        NumHeight = options.height or 1,
        BackIsHidden = options.hiddenBack or false,
        UniqueBack = options.uniqueBack or false
    }
    -- Reuse ID if asset existing
    asset.id = assetID(asset.data)
    return setmetatable(asset, assetMeta)
end
-- Pull a Decker.Asset from card JSONs CustomDeck entry
local function assetFromData(assetData)
    return setmetatable({data = assetData, id = assetID(assetData)}, assetMeta)
end

-- Create a base for JSON objects
function Decker.BaseObject()
    return {
        Name = 'Base',
        Transform = {
            posX = 0, posY = 5, posZ = 0,
            rotX = 0, rotY = 0, rotZ = 0,
            scaleX = 1, scaleY = 1, scaleZ = 1
        },
        Nickname = '',
        Description = '',
        Value = 0,
        Tags = {},
        ColorDiffuse = { r = 1, g = 1, b = 1 },
        Locked = false,
        Grid = true,
        Snap = true,
        Autoraise = true,
        Sticky = true,
        Tooltip = true,
        GridProjection = false,
        Hands = true,
        XmlUI = '',
        LuaScript = '',
        LuaScriptState = '',
        GUID = 'deadbf'
    }
end
-- Typical paramters map with defaults
local commonMap = {
    name   = {field = 'Nickname',    default = ''},
    value   = {field = 'Value',    default = 0},
    tags   = {field = 'Tags',   default = {}},
    desc   = {field = 'Description', default = ''},
    script = {field = 'LuaScript',   default = ''},
    xmlui  = {field = 'XmlUI',       default = ''},
    scriptState = {field = 'LuaScriptState', default = ''},
    locked  = {field = 'Locked',  default = false},
    tooltip = {field = 'Tooltip', default = true},
    guid    = {field = 'GUID',    default = 'deadbf'},
    hands   = {field = 'Hands',   default = true},
}

the guid being 'deadbf' - which I read as "dead boyfriend"?? Nonetheless...

My solution has been to generate a new GUID for each object, something akin to the following:

math.randomseed(os.time())
local function randStr(k)
    local alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
    local n = string.len(alphabet)
    local pw = {}
    for i = 1, k
    do
        pw[i] = string.byte(alphabet, math.random(n))
    end
    return string.char(table.unpack(pw))
end

local function newGuid()
    return randStr(6)
end

-- Create a new CustomDeck asset
function Decker.Asset(face, back, options)
    local asset = {}
    options = options or {}
    asset.data = {
        FaceURL = face or error('Decker.Asset: faceImg link required'),
        BackURL = back or error('Decker.Asset: backImg link required'),
        NumWidth = options.width or 1,
        NumHeight = options.height or 1,
        BackIsHidden = options.hiddenBack or false,
        UniqueBack = options.uniqueBack or false,
        GUID = newGuid()
    }
    -- Reuse ID if asset existing
    asset.id = assetID(asset.data)
    return setmetatable(asset, assetMeta)
end
-- Pull a Decker.Asset from card JSONs CustomDeck entry
local function assetFromData(assetData)
    return setmetatable({data = assetData, id = assetID(assetData)}, assetMeta)
end

-- Create a base for JSON objects
function Decker.BaseObject()
    return {
        Name = 'Base',
        Transform = {
            posX = 0, posY = 5, posZ = 0,
            rotX = 0, rotY = 0, rotZ = 0,
            scaleX = 1, scaleY = 1, scaleZ = 1
        },
        Nickname = '',
        Description = '',
        Value = 0,
        Tags = {},
        ColorDiffuse = { r = 1, g = 1, b = 1 },
        Locked = false,
        Grid = true,
        Snap = true,
        Autoraise = true,
        Sticky = true,
        Tooltip = true,
        GridProjection = false,
        Hands = true,
        XmlUI = '',
        LuaScript = '',
        LuaScriptState = '',
        GUID = newGuid()
    }
end
-- Typical paramters map with defaults
local commonMap = {
    name   = {field = 'Nickname',    default = ''},
    value   = {field = 'Value',    default = 0},
    tags   = {field = 'Tags',   default = {}},
    desc   = {field = 'Description', default = ''},
    script = {field = 'LuaScript',   default = ''},
    xmlui  = {field = 'XmlUI',       default = ''},
    scriptState = {field = 'LuaScriptState', default = ''},
    locked  = {field = 'Locked',  default = false},
    tooltip = {field = 'Tooltip', default = true},
    guid    = {field = 'GUID',    default = 'deadbf'},
    hands   = {field = 'Hands',   default = true},
}
-- Apply some basic parameters on base JSON object
function Decker.SetCommonOptions(obj, options)
    options = options or {}
    for k,v in pairs(commonMap) do
        -- can't use and/or logic cause of boolean fields
        if options[k] ~= nil then
            obj[v.field] = options[k]
        else
            obj[v.field] = v.default
        end
    end
    -- passthrough unrecognized keys
    for k,v in pairs(options) do
        if not commonMap[k] then
            obj[k] = v
        end
    end
    obj.GUID = newGuid()
end

I'm not sure what implications this has for TTS - e.g. what if a duplicate GUID is generated? The chances of this are very low (there are 1.3537087e+16 combinations of 6 digit chars) - but I'm not sure how the GUIDs are generated internally, and whether re-seeding math.random is bad?

I'm not a LUA scripter!

[tjakubo]

Hey, thanks for the kind words and nice find, I did not expect TTS to mess with unrelated object fields because of duplicate GUIDs :)

The deadbf fixed GUID was just "anything" inspired by typical 32 bit dummy address 0xDEADBEEF (https://en.wikipedia.org/w/index.php?title=Magic_number_(programming)&useskin=vector#DEADBEEF). Idea was, let this GUID be duplicate so TTS reassigns it to a free one automatically when spawning - that's what happens when you for example copy-paste any object manually, or draw from an infinite bag, without scripting.

But since it seems to be problematic, I'll add random GUID generation - this will mean it shouldn't clash with any other GUIDs, and won't be a guarantee... but like you said, it's going to be a very slim chance.
As far as seeding goes, Moonsharp (the library TTS uses to handle scripting) does that for us, so it shouldn't be a problem.

By the way, an easier way of generating a random GUID is just rolling a random number in its range (16 chars in 6 spots, so 16^6 which is equal to 2^24) and converting it to hex string. Uppercase/lowercase should not make a difference there.

function random_guid()
  local value = math.random(0, 2^24)
  return string.format('%x', value)
end

Thanks for the report, I'll fix that and add a test for this case sometime next week as I'm out for the weekend :)