[General] 2 JASS Questions

[Zaio]

Hey Hive, i got 2 JASS related questions that i cannot for the life of me figure out. Will be very greatfull to anyone who can answer them.

1. If you save a local group to a hashtable, then set a local group as the saved group, must you destroy the loaded group or will that also destroy the saved group? I never really had to save unit groups into hashtables so only now is this becomming an issue, since i dont want leaks.

2. How can you create a rect between 1 unit to another give or take 50 units wide? I am not sure what calculation (if any) is required to achieve this.

 

[Bannar]

1. Hashtables dont leak, but you can always free the data they store if you don't need it anymore:

// for single child key removal:
call RemoveSavedHandle(hash, id, childkey)

// for whole parent key removal:
call FlushChildHashtable(hash, id)

2. Elaborate.

 

[Zaio]

1. I dont mean about the hashtable leaking, i mean about the loaded group leaking, every time i load a group from a hashtable, must i destroy it? Or just null it and destroy it when i flush the hashtable?

2. Like Tether from DotA, the blue lightning between 2 units where they create a rect to pick units to stun in, how can i make a rect like that?

 

[Bannar]

1. Take a look:

// Lets say you have saved group handle and now you load it
local group g = LoadGroupHandle(somehash, someid, 0)
// stuff related to manipulate the group
call DestroyGroup(g)
set g = null
// If saved handle is needed no more you can either
call RemoveSavedHandle(somehash, someid, 0) // to remove just child key

// Or if you want to clear whole parent key
call FlushChildHashtable(somehash, someid)

2. I think there it's all about creating temporary regions with:

native SetRect                  takes rect whichRect, real minx, real miny, real maxx, real maxy returns nothing

Where minx/y will be referend to caster's position and maxx/y to the target's position.

 

[baassee]

2.

Something like this should do it.

Link

 

[Zaio]

Ok thanks spinnaker about 1, however 2 wont create a wide rect since its just a rect from 1 pos to another, it will be pencil line thin most likely, how can i make it 50 units wide? And sry baassee i dont really understand that code nor what it is meant to do.

 

[baassee]

Then you just increase one of the y coordinates with 50.

 

[Zaio]

Hmm, just ONE of the ys? Wouldnt that make it more triangle shape?

 

[baassee]

The rect formula uses two points in a rect, the downleft corner and the upright corner. If theyre on the same y coordinate then it will be a paperthin line as you mentioned.

 

[Zaio]

Ok thanks, rep

 

[Zwiebelchen]

1. I dont mean about the hashtable leaking, i mean about the loaded group leaking, every time i load a group from a hashtable, must i destroy it? Or just null it and destroy it when i flush the hashtable?

Depends on what you do with that group or if you have other references to the group.
I think you mistake the hashtable for something it isn't. A hashtable is nothing else than a two-dimensional array.

If you store a group into an array and retrieve it when you need it, you wouldn't ask that question, would you?
If you save a group to a hashtable, you don't really put that group into there, all you do is storing a "link" to that group there. If you remove a group from a hashtable by using "RemoveSavedHandle", the link gets destroyed, but not the group. If you "DestroyGroup" inside the hashtable, the entire group gets destroyed. If you used it elsewhere, it doesn't work anymore.
Hope this was the answer to your question?