Problem with UnitDynamicFlags.Dead

[miceiken]

Okay everyone, so I just realized that my WoWUnit.Dead function doesn't work to well, in fact it always returns false! The weird thing is that for instance WoWUnit.Lootable that also is an UnitDynamicFlag returns true when a corpse is lootable. Here's some code:

UNIT_DYNAMIC_FLAGS = 0x4E // 0x4E * 4 = 0x138
UnitDynamicFlags.Dead = 0x20,

public bool HasDynamicFlag(Enums.UnitDynamicFlags flag)
{
    return ((Memory.Read<int>(UnitDescriptor + (uint)Descriptors.eUnitFields.UNIT_DYNAMIC_FLAGS * 4)) & (int)flag) != 0;
}

public bool Dead
{
    get
    {
        return HasDynamicFlag(Enums.UnitDynamicFlags.Dead);
    }
}

public bool Lootable
{
    get
    {
        return HasDynamicFlag(Enums.UnitDynamicFlags.Lootable);
    }
}

 21:21:43  Target Info: Bristleback Thornweaver
 21:21:43    Combat: False
 21:21:43    Casting: False
 21:21:43    Dead: False
 21:21:43    Facing: 1,093227
 21:21:43    Faction: 111
 21:21:43    GUID: 17379391016734158679
 21:21:43    Level: 18
 21:21:43    Lootable: True
 21:21:43    Skinnable: False
 21:21:43    Tagged: True
 21:21:43  ------------------------------------

Notice how the Lootable = true, yet the Dead = false!

[TOM_RUS]

Checking dynamic flags to ensure that unit is dead isn't correct.
Better check health or something else.

[miceiken]

I see, just thought that this was the safest way to do it...

[XTZGZoReX]

Health should be your best bet, indeed.

[Apoc]

The 'Dead' flag doesn't ensure the unit is dead. It just ensures it has a gray name.

WoW uses if (unit.Health <= 0) to check for dead.

[miceiken]

Okay, thanks

[XTZGZoReX]

Just for the record: dynamicflags are only for visuals. Keep in mind that a unit can appear dead without actually being dead.

[Nesox]

The 'Dead' flag doesn't ensure the unit is dead. It just ensures it has a gray name.

WoW uses if (unit.Health <= 0) to check for dead.

Wouldn't that make the 'Dead' flag same as the Tagged? o.O

[kolis764]

i think hes saying that the unit would be under level has their name would show in gray. I think you got your flag & wrong.

public bool HostileToPlayer {
    get { return ((Faction & HostileToPlayerFlag) != HostileToPlayerFlag); }
}

if you do and operator on a field it will return the checked flag if it is correct, so not, not 0 has stated above.

[Apoc]

i think hes saying that the unit would be under level has their name would show in gray. I think you got your flag & wrong.

public bool HostileToPlayer {
    get { return ((Faction & HostileToPlayerFlag) != HostileToPlayerFlag); }
}

if you do and operator on a field it will return the checked flag if it is correct, so not, not 0 has stated above.

Uhhh... right...

if ((flags & flag) != 0)

^ That's all you need to check flags. It's a full bitwise AND, so anything other than 0 means it's 'on'.

[kolis764]

what if your flag IS 0

[Apoc]

Then it still works?

Please read up on how the AND operation works.

[kolis764]

1101
0000
____
0000

Is equal to zero so no it doesnt work. The result of a AND should be the flag you are looking for period.


L2BINARY

second point

[adaephon]

Except that zero would indicate the absence of all flags, and thus is an illogical situation.

Edit:

public bool HostileToPlayer {
    get { return ((Faction & HostileToPlayerFlag) != HostileToPlayerFlag); }
}

Faction = 1111
HostileToPlayerFlag = 1010
Result = 1010
return result != HostileToPlayerFlag
1010 != 1010 -> false -> HostileToPlayer is incorrectly false.

[MaiN]

1101
0000
____
0000

Is equal to zero so no it doesnt work. The result of a AND should be the flag you are looking for period.


L2BINARY

second point

It all comes down on how you like it to work.
If you use != 0, it will return true if you have any of the flags in the value you AND with set.
That means (with != 0):
1001
& 1010
will return 1000, hence != 0 will be true. If you however want to check for all of the flags, you should use '== flag'. In that case:
1001
& 1010
still returns 1000, hence == 1010 will be false.

TL;DR;
Use != 0 if you want to check for one of more flags in a single operation. Usually you will only check on a single flag where != 0 and == flag will be the same.