[Solved] Unit Group Iterating Can't Get Casting Unit

[Black-apples]

Good Evening everyone,

I'm working on transitioning to LUA. I'm trying to remake the melee Blizzard spell in LUA. I have my code almost finished, but I've run into a minor hiccup. I've been banging my head against a wall for hours, so I hope somebody else can see my mistake.

The problem essentially is that a call to GetSpellAbilityUnit() does not return a valid unit depending on where I use it in code. I'm not sure how this function gets the casting unit. I am only using this within the trigger's actions.

The spell is supposed to pick a group of enemies in a range and damage them. I can successfully create a unit group with the enemies in it, and iterate through each enemy. In the callback for iterating through the unit group I try to call GetSpellAbilityUnit() to get the caster, however, this variable seems to be empty. The print statement doesn't print anything, and the damage function doesn't do any damage either.

I made this spell by first coding it the way I would in GUI (and of course testing it), observing the generated LUA, then rewriting it in my own way in a custom trigger. The format and process is identical.

The following is the code

Spoiler

--Globals
fakeBlizzTrg = nil
--End Globals

function valid1()
    return (IsUnitAliveBJ(GetFilterUnit()) == true)
end

function valid2()
    return (IsUnitEnemy(GetFilterUnit(), GetOwningPlayer(GetSpellAbilityUnit())) == true)
end

function unitValid()
    return GetBooleanAnd(valid1(), valid2())
end

function Trig_Fake_Blizzard_Func001A()
    print("Effect Start")
    local target = GetEnumUnit()
    print(GetUnitName(target))
    print(GetUnitName(GetSpellAbilityUnit()))
    local damage = 50.0
    print(damage)
    UnitDamageTargetBJ(GetSpellAbilityUnit(), target, 50.0, ATTACK_TYPE_NORMAL, DAMAGE_TYPE_NORMAL)
    SetUnitMoveSpeed(target, GetUnitDefaultMoveSpeed(target) * 0.35)
    print("Effect End")
end

function runTrig()
    print("Run")
    if (GetSpellAbilityId() == FourCC('AHbz')) then    --Ability was blizzard
        local caster = GetSpellAbilityUnit()
        local castLoc = GetSpellTargetLoc()
        IssueImmediateOrderBJ(caster, "stop")

        --Blizzard timer
        local t1 = CreateTimer()
        local count = 0
        local maxWaves = 5
        local group = CreateGroup() --Holds all units hit by this spell. Used to undo spell effects
        print("Start")
        TimerStart(t1, 1.00, true, function()
            --createBlizzardEffect(caster, castLoc, group)
            local ug = GetUnitsInRangeOfLocMatching(
                2000.00,
                castLoc,
                Condition(unitValid)
            )
            print("Made")
            print(CountUnitsInGroup(ug))
            ForGroupBJ(ug, Trig_Fake_Blizzard_Func001A)
            print("Wave end")

            count = count + 1
            if(count >= maxWaves) then
                --End blizzard
                print("End")
                PauseTimer(t1)
                DestroyTimer(t1)
            end
        end)
    end
end

function initFakeBlizzard()
    print("Blizz init")
    fakeBlizzTrg  = CreateTrigger()
    TriggerRegisterAnyUnitEventBJ(fakeBlizzTrg , EVENT_PLAYER_UNIT_SPELL_EFFECT)
    TriggerAddAction(fakeBlizzTrg  , runTrig)
    print("Blizz initialized")
end

I apologize in advance for the spaghetti code.

 

[Pyrogasm]

This explains what works when/where: Event Response Myths. In general, use GetTriggerUnit anywhere you can. If you use embedded functions for your ForGroup callbacks and Condition things, you can reference local variables from the parent function they're embedded in, which is probably how I would suggest you refer to the unit.

 

[Black-apples]

Thank you very much! That's an awesome resource. By habit I avoid embedded functions to reduce complexity. I guess that doesn't really matter here.

 

[Anachron]

You never reset the hit units movespeeds.