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GUIDs are most safer than pointers and in some cases can avoid segmentation faults.
== - ==
Let me show a simple example:
We have a pointer to a creature: Creature *pCreature;
and try to search a creature and store it in the pointer:
pCreature = SearchCreature(ID);
We can check simply if the creature found or not:
if(pCreature)
- if this give true: creature found and we have a memory address which points to the creature
- if this give false: creature not found and this is a NULL pointer
Suppose that we have a valid pointer, so creature found.
We wanna use that pointer somewhere, for example in script phase 3.
But we delete the creature(from world) in phase 1.
In phase 3:
if(pCreature)
pCreature->DoSomeShit();
The if condition gives true, but pCreature points to an _invalid_ address.
In that address maybe have "nothing" or another creature's object or a player or anything else, dont know that.
~~ - ~~
Let me show the correct way:
Creature's GUID: uint64 CreatureGUID;
search the creature and set the GUID:
Creature *pCreature = SearchCreature(ID);
CreatureGUID = pCreature ? pCreature->GetGUID() : 0; // if pCreature is NULL set the GUID to 0
So we have a GUID and not a pointer.
We can get the creature from that GUID:
Creature *pCreature = GetCreature(CreatureGUID);
and we can simply check it is valid or not(found or not):
if(pCreature)
So we deleted the creature in phase 1 and try to use it in phase 3:
Creature *pCreature = GetCreature(CreatureGUID);
And this gives NULL because GetCreature() can't find the creature which GUID is CreatureGUID.
if(pCreature) // pCreature is NULL
pCreature->DoSomeShit(); // DoSomeShit() not called
== - ==
Remove some not used variables.
Some clean.
TODO: Should search/fix these in zones scripts.
--HG--
branch : trunk
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