backstabibility

[lynx]

From what I've read, any melee weapon useable by single class thieves can be used for backstabbing.

 

I've seen some mods that make backstabbing possible with other weapons too (item revisions?). It appears to be done by just making those weapons usable by thieves.

 

UAI does not affect backstabibility, but it only modifies a stat, which is (at least in the gemrb case) checked before the real usability.

 

Is the item's (un)usability bitfield really the only way of making a weapon usable to backstab?

[Taimon]

There is no execution path that bypasses the item usability check.

(I'm tempted to waste a item flag on this one ...)

[lynx]

An item flag would be the best, but I find it a little odd that they would add a flag that disables backstabibility instead of having a normal backstabibility bit in the first place.

 

Or maybe it is both, a weapon can be used for backstabbing if it is usable by a thief or has a bit set. Or maybe it is set at load time based on the usability ... Calls for some testing, as there are plenty of unknowns in the itm and ext header flags fields.

[Taimon]

I'm not sure what you are talking about.

Currently, there is no specific flag that enables/disables backstabbing.

I was thinking about patching one in.

 

To answer your first question more clearly:

Is the item's (un)usability bitfield really the only way of making a weapon usable to backstab?

Yes, you can't bypass the thief usability check.

[Avenger]

What about ranged weapons usable by thieves?

That's already 2 flags.

 

In BG2 you cannot backstab by ranged weapons (can you?)

In NWN and (OOTS comics:) you can backstab/sneak attack by bow+arrow.

So it seems there is a room for interpretations, engine/game versions.

 

A separate item flag seems to be the best solution, so once you 'patch one in', we'll use the same in GemRB.

[Taimon]

In BG2 you cannot backstab by ranged weapons (can you?)

No, it's like the first check in the backstabbing code. (abiliy type == 2)

 

A separate item flag seems to be the best solution, so once you 'patch one in', we'll use the same in GemRB.

Two things that I'm still thinking about:

Should it be an item flag or an item ability flag?

And should that flag also bypass the ranged weapon check?

[Icendoan]

IMO, it should. There is no reason if you have time to aim that you can't hit as critically with a crossbow than with a dagger.

 

Icen

[Avenger]

An item ability flag is more flexible.

Just please don't use flags already used in iwd2!

For example: the keen bit.

It would be a hell of a job to sort them out.

And impossible to support both at the same time.

[the bigg]

Item ability allows fine-tuning for melee/thrown mixed use weapons, so it's better.

[Ardanis]

Item ability allows fine-tuning for melee/thrown mixed use weapons, so it's better.

[Taimon]

Just please don't use flags already used in iwd2!

I'm usually picking bits from the last byte, so that should be fine. Let's say Bit 25?

(The ability flags are a dword, at least in ToB.)

 

Shouldn't be too difficult, but first I have to fix the attacks per round stacking, which will take some time, since I have to rewrite the whole effect and probably some other things too.

[Avenger]

The IWD2 flags are on the high part of the dword (but i guess they are bit 16,17).

 

0x0026 2 (word) Flags

0x0028 2 (word) Attack type

 

* 0 = Normal

* 1 = Bypass armor

* 2 = Keen

 

 

I plan to discover all bits, sometime.

Btw, do you see only those 4 (for bg2) that are already documented on IESDP?

[Taimon]

Btw, do you see only those 4 (for bg2) that are already documented on IESDP?

Yep, only those.

I didn't find a reference to the breakable flag in the ToB executable, maybe they removed it in BG2.

[Avenger]

I did an extensive research in the games (checked the item flags).

So, no more than 6 bits are used (2 are used only in iwd2 - keen and ignore shield/armor bonuses).

 

None in the highest byte.

[Taimon]

Good, that leaves some room for patching things.

 

By the way, I did implement the backstab flag. (Bit 25 in the item ability flags.)

The patch also checks the launcher if the flag is not set in the ammunition.