Saving values to different tables in a loop.

Niketa · 07-31-13, 01:53 AM

I'm trying to go through each mount a player has and add that to a table "flying", "ground" or "aquatic" within the table "mounts". With the code I currently have it, it doesn't add them to a table.

However, if I take out the bit of code to add to ground or aquatic (the elseifs) and have it just add to the flying table it works just fine (and I don't think it's just the flying in particular, but rather I can only add to one sub-table rather than multiple ones).

Is there an error in my code or is it just not possible with this approach?

Lua Code:

local mounts = {}
    mounts.flying = {}
    mounts.ground = {}
    mounts.aquatic = {}
 
local amount = GetNumCompanions("mount")
 
local f, g, a = 1
 
for i = 1, amount do
    local creatureID, creatureName, creatureSpellID, icon, issummoned, mountType = GetCompanionInfo("mount",i)
    
    if mountType == 7 or mountType == 15 or mountType == 23 or mountType == 31 then
        mounts.flying[f] = {creatureID, creatureName, creatureSpellID, icon, issummoned, mountType}
        --print(mounts.flying[f][2])
        f = f + 1
    elseif mountType == 29 then
        mounts.ground[g] = {creatureID, creatureName, creatureSpellID, icon, issummoned, mountType}
        --print(mounts.ground[g][2])
        g = g + 1
    elseif mountType == 12 then
        mounts.aquatic[a] = {creatureID, creatureName, creatureSpellID, icon, issummoned, mountType}
        --print(mounts.aquatic[a][2])
        a = a + 1
    end
end

Malsomnus · 07-31-13, 02:19 AM

First thing that pops up for me is the line:

Lua Code:

local f, g, a = 1

Is it possible that what you meant to write is

Lua Code:

local f, g, a = 1, 1, 1

?

[Edit]
It really looks like lines 18, 20, 22 and 24 should complain about indexing/ arithmetic with nil values. Do you get these errors?
Anyway instead of managing indexes you can just use:

Lua Code:

table.insert (mounts.flying, {creatureID, creatureName, creatureSpellID, icon, issummoned, mountType})

Phanx · 07-31-13, 03:02 AM

tinsert is definitely the way to go here. Keeping track of the indices yourself is just masochistic.

Also, the mountType returned by GetCompanionInfo is a bitfield, not a decimal value, so rather than trying to account for all possible combinations, you should just use bit operators to check the specific flags you're interested in:

Code:

if bit.band(mountType, 0x8) ~= 0 then
    -- aquatic
elseif bit.band(mountType, 0x2) ~= 0 then
    -- flying
elseif bit.band(mountType, 0x1) ~= 0 then
   -- ground
end

The order is fairly important, as mounts can be flagged as flying and ground, for example; the above prioritizes any flight-capable mount as a flying mount, so it will only consider mounts to be ground mounts if they can't fly.

On a side note, you're creating your mounts table in the least efficient way possible. Instead of this:

Code:

local mounts = {}
    mounts.flying = {}
    mounts.ground = {}
    mounts.aquatic = {}

...do this:

Code:

local mounts = {
    flying = {},
    ground = {},
    aquatic = {}
}

Works out exactly the same, and doesn't cost all the extra lookups.

Niketa · 07-31-13, 04:12 PM

Thank you guys. Helpful as usual.

Niketa · 07-31-13, 11:49 PM

When I first log on the tables don't automatically populate and I have to /reload to get them to populate.

I've tried leaving the code outside of any event, tried PLAYER_LOGIN, PLAYER_ENTERING_WORLD and PLAYER_ALIVE.

Malsomnus · 08-01-13, 02:05 AM

Ah, I hate data that isn't available on PLAYER_ENTERING_WORLD. I've found myself several times putting such code in a function that gets called from OnUpdate after it counts a few seconds.
I'd love to hear if anybody knows a correct way of doing that