How do I set ability cast range using triggers?

[afisakov]

I know how to change the aoe or distance an ability flies based on variables, but I don;t know how to determine cast range based on it.
I thought of setting cast range to 9999 and adding a condition like:

    set tp1=GetUnitLoc(caster)
    set tp2=GetUnitLoc(target)
    set ax=DistanceBetweenPoints(tp1,tp2)
    call RemoveLocation(tp1)
    call RemoveLocation(tp2)
    if(ax<600.+myvariable)then
        return true
    endif
return false

However, if it if false it not only prevents the cast but also puts the ability ability into cooldown. Given a 10 sec cooldown I would prefer if players didn't lose their chance to cast too often to errors.

Is there a better way to do it, or maybe a way to reset the ability's cooldown if cannot cast?

P.S. initial ability condition is
"return (GetSpellAbilityId()=='A0AW')" and runs before the one listed above

 

[Imp Midna]

- afaik, you can not set the cast range of an ability using triggers
- at spell effect event, you may still interrupt the execution of a spell, e.g. by moving him to the position he currently is at. The mana will still be lost, so you will have to add it again
- you can reset the cooldown of a spell by removing and adding it again

 

[afisakov]

darn, I was hoping there was some line I didn't know about that would more easily reset the spell, but I guess that will do. Thank you, I will implement it that way then.

 

[afisakov]

Ok, I implemented this as a condition to any of the ability's trigger effects (rest does 0 damage anyway). I reset by removing and readding ability cooldown. Trigger posted below.

However, I have to ask if there is a way to have the unit resume prev actions, like if I try to cast to shorten a walk and can't, the unit keeps walking to prev destination?

my trigger

function rangecheck takes unit u1, unit u2, integer a0b, real ran1 returns boolean
    set tp1=GetUnitLoc(u1)
    set tp2=GetUnitLoc(u2)
    set ax=DistanceBetweenPoints(tp1,tp2)
    call RemoveLocation (tp1)
    call RemoveLocation (tp2)
    set fint4=GetUnitAbilityLevel(u1,a0b)
    if ax<ran1 then
        return true
    else
        call UnitRemoveAbility(u1,a0b)
        call UnitAddAbility(u1,a0b)
        call SetUnitAbilityLevel(u1,a0b,fint4)
        call DisplayTimedTextToPlayer(GetOwningPlayer(u1),0,0,4,"Out of range")
        call PlaySoundBJ(udg_sounderror)
        return false
    endif
endfunction

also if you know other things to improve the trigger or a better way to do this, let me know.

Actually, I just had an idea. If I made a condition for unit begins casting an ability instead of starts the effects of, and ordered it to stop, would that prevent the main trigger from activating and avoid the mana cost and cooldown issue altogether?

 

[dracolich]

event - unit start to cast spell
spell is equal to UR_SPELL
if DIST_BETWEEN_TARGET_AND_CASTER > 600+var then
issue STOP order to caster
endif