[JASS] Efficiency

[Garfield1337]

I was wondering what way of enumerating units is more efficient:
1. Enumerating a unit group using GroupEnumUnitsInRange and doing all actions within filter with filter always returning false.
2. Adding units to a unit group variable and looping through units by picking a random unit in group,executing actions and removing the unit from group.

I heard that using loop instead of group enumeration is more efficient, which is, i guess, the second way
Or is there a more efficient way than these two?

 

[PurgeandFire]

The filter enumeration method (1st one) is faster.

The second method might be faster than ForGroup() (for one-instance groups or something like that), but not faster than the filter enumeration. Filter enumeration performs the actions as the units are being grouped.

 

[Garfield1337]

Thanks for response.
Still, Bribe said that it's better to use loop than group enumeration in a comment on one of my spells; i guess he meant the ForGroup enumeration.
So how would i do a loop instead of using ForGroup since it's not a dynamic enumeration, i want to keep units grouped so removing them wouldn't work?

 

[PurgeandFire]

Hmmm.. I'm not sure what he means exactly. Maybe he wants you to keep a list of the members, but it is kind of impractical. IMO I'd stick with ForGroup() if you need it to keep the members.

Could you link his post? Maybe I am misinterpreting the idea.

 

[Garfield1337]

You can find it on moderator comment on spell: http://www.hiveworkshop.com/forums/spells-569/chicken-burst-v0-2-a-193124/#post1888419

It would be more efficient with a loop instead of a group-enumeration.

 

[Dr Super Good]

As far as I am aware, for group is faster than breaking a group appart in a loop quite substantially as removing units from groups perform a lot of overhead.

 

[Garfield1337]

I guess i'll contact Bribe as soon as he comes online to see what he meant.

 

[WaterKnight]

You should also take into account that it depends on how much data you need to globally pass/reload to an outsourced filter/ForGroup-function.

 

[Bribe]

Two things need to be distinguished.

1. The replies you've gotten in this thread appear to be based on the thought you would only be enumerating these units once, and not repeatedly. So they thought you meant this:

call GroupEnum...
loop
    set u = FirstOfGroup(g)
    exitwhen u == null
    call GroupRemoveUnit(g, u)
    //Actions
endloop

But since you reference these again and again, many times, you could use a different data structure - store each instance into an array slot, and loop through that array.

 

[Garfield1337]

Oh..didn't think of using an array, sorry for inconvenience.

 

[Bribe]

It's no inconvenience.

 

[Troll-Brain]

Two things need to be distinguished.

1. The replies you've gotten in this thread appear to be based on the thought you would only be enumerating these units once, and not repeatedly. So they thought you meant this:

call GroupEnum...
loop
    set u = FirstOfGroup(g)
    exitwhen u == null
    call GroupRemoveUnit(g, u)
    //Actions
endloop

But since you reference these again and again, many times, you could use a different data structure - store each instance into an array slot, and loop through that array.

While this kind of loop is neat coz you don't split the code, i hardly believe that is more efficient than directly coding inside the filter of GroupEnum.
But it shouldn't matter thought, since this kind of loop is for unique usage.

And yes i'm agree an array defined inside the GroupEnum should be better here.

 

[Bribe]

That's still not what I was referring to.

Every 0.03 seconds he was calling "ForGroup(g)" on a group to do some periodic stuff. An array is much better served for the periodic stuff though.

 

[Troll-Brain]

Your previous answer is confusing, i've said here the best option is using an array, but i mean there is no situation where a ForGroup loop would be more efficient than coding directly inside the filter of GroupEnum.

 

[Bribe]

In a situation where you have tons and tons of local variables that all need to be referenced during the group-pick process, a FirstOfGroup loop can be faster. Otherwise I agree, a ForGroup should always be replaced by an inlined Filter when they can do the same thing (filter returning false).

 

[Troll-Brain]

In a situation where you have tons and tons of local variables that all need to be referenced during the group-pick process, a FirstOfGroup loop can be faster. Otherwise I agree, a ForGroup should always be replaced by an inlined Filter when they can do the same thing (filter returning false).

Ok let's say "in any real scenario" if you care that much