Header:

Every Item File Contains A Header. It Contains The Basic Properties Of The Item Represented By The File.
 

Offset	Size	Description
0000h	0004h	FileType
0004h	0004h	FileRevision
0008h	0004h	ItemNameReference(UnIdentfied)
000Ch	0004h	ItemNameReference(Identified)
0010h	0008h	UsedUpItemFile
0018h	0002h	ItemAttributes
001Ah	0002h	_ZERO *
001Ch	0002h	ItemType
001Eh	0004h	Useability
0022h	0002h	ItemAnimation
0024h	0002h	?MinLevel *
0026h	0002h	?MinStrength *
0028h	0002h	?MinStrenghtBonus *
002Ah	0002h	?MinIntelligence *
002Ch	0002h	?MinDexterity *
002Eh	0002h	?MinWisdom *
0030h	0002h	?MinConstitution *
0032h	0002h	?MinCharisma *
0034h	0004h	ItemPrice
0038h	0002h	ItemStack
003Ah	0008h	InventoryIcon
0042h	0002h	LoreToIdentify
0044h	0008h	GroundIcon
004Ch	0004h	ItemWeight
0050h	0004h	DescriptionReference(UnIdentified)
0054h	0004h	DescriptionReference(Identified)
0058h	0008h	DescriptionIcon
0060h	0004h	????
0064h	0004h	ExtendedHeaderOffset
0068h	0002h	ExtendedHeaderCount
006Ah	0004h	FeatureTableOffset
006Eh	0002h	_ZERO *
0070h	0002h	FeatureBlockCount (Only The Feature Blocks That Affect The User Of The Item)

* not implemented in Baldur's Gate
 

Extended Header:

If An Item Affects Other Creatures, Like A Weapon Or A Wand, The Item File Contains An Extended Header:
One ExtendedHeader Equals One Ability Of An Item.
 

Offset	Size	Description
0000h	0001h	AbilityType
0001h	0001h	ForceIdentify (Item Must Be Identified To Be Used)
0002h	0002h	???? (seems to affect item type?)[0 - ] [1 weapon/default] [2 -] [3 magic] [4 gem/bandit skalp]
0004h	0008h	EquiptIcon
000Ch	0002h	Target
000Eh	0002h	EffectRadius / AttackRange (feet)
0010h	0002h	ProjectileType
0012h	0002h	SpeedFactor
0014h	0002h	THAC0 Bonus
0016h	0002h	BaseDamage
0018h	0002h	Throws
001Ah	0002h	DamageBonus
001Ch	0002h	DamageType
001Eh	0002h	FeatureBlockCount (Only The Feature Blocks That Affect The Attacked Creature)
0020h	0002h	FeatureBlockOffset (Index Of The First Feature Block That Belongs To This Extended Header)
0022h	0002h	Charges
0024h	0006h	????
002Ah	0002h	EffectAnimation (not only graphic!!!)
002Ch	000Ch	????

 

Feature Block:

Items With Magical Capabilities Contain One Or More Feature Blocks. Every Feature Block Represents One Special Ability Of An Item.

 

Offset	Size	Description
0000h	0001h	Feature/Effect
0001	0001h	????
0002h	0001h	TargetIdentifier
0003h	0001h	????
0004h	0004h	Parameter 1
0008h	0004h	Parameter 2
000Ch	0001h	EffectTimeMode
000Dh	0001h	????
000Eh	0004h	EffectTime
0012h	0002h	Probability
0014h	0008h	FileName
001Ch	0004h	Throws
0020h	0004h	DiceSides
0024h	0004h	SavingThrowType
0028h	0004h	SavingThrowBonus
002Ch	0004h	????

 
 
 

Header:

FileType:
 

Offset	Size	Data	Type	Default Data
0000h	0004h	FileType	Array[0..3] Of Char	'ITM '

This Field Contains The Type Of The Data File. It Should Be The Same As The File Extension.
 
 

FileRevision:
 

Offset	Size	Data	Type	Default Data
0004h	0004h	FileRevision	Array[0..3] Of Char	'V1 ' or 'V1.0'

Revision Of The Data File. In BG I've Only Found 'V1.x' Files, But This May Change With Future Expansions.
 
 

ItemNameReference(UnIdentified):
 

Offset	Size	Data	Type	Default Data
0008h	0004h	ItemNameReference	Longint	FFFFh for none

This Is The Reference To The Name Of The (Unidentified) Item. The Reference Is The Index Of The Name String Contained In Dialog.tlk.

ItemNameReference(Identified):
 

Offset	Size	Data	Type	Default Data
000Ch	0004h	ItemNameReference	Longint	FFFFh for none

This Is The Reference To The Name Of The (Identified) Item. The Reference Is The Index Of The Name String Contained In Dialog.tlk.
 
 

UsedUpItemFile:
 

Offset	Size	Data	Type	Default Data
0010h	0008h	UsedUpItemFile	Array[0..7] Of Char

This Field Contains The FileName Of An ItemFile. If The Item Gets Destroyed (Used Up), It Will Get Replaced By The Item Specified In This Field.
 
 

ItemAttributes:
 

Offset	Size	Data	Type	Default Data
0018h	0002h	ItemAttributes	(Array Of?) Boolean

This Field Is Some Kind Of Boolean Array:
 

Byte 01

Offset 0018h

Bit	Data	Description
0	Indestructable	Item Won't Disapear On The Ground.
1	TwoHanded	The User Of This Item Isn't Allowed To Use A Shield
2	Dropable	Item Won't Drop On The Ground If Possessing Creature Dies
3	Displayable
4	Cursed	The Item Is Cursed And Cannot Be Removed Without A Remove Cursed Item Spell.
5	????
6	Magical	Magical Item
7	?Bow	Item Is A Bow?

Bit 0 is the LSB, Bit 7 the MSB
 
 

ItemType:
 

Offset	Size	Data	Type	Default Data
0001Ch	0002h	ItemType	Word

It Can Contain The Following Values:
 

Value	Item Type	Inventory
0000h	Book
0001h	Amulet/Necklace	(Amulet)
0002h	Armor	(Armor)
0003h	Belt	(Belt)
0004h	Boots	(Boots)
0005h	Arrow	(Quiver)
0006h	Bracers	(Bracer)
0007h	Helmet	(Helmet)
0008h	<NONE>	(Quick Item)
0009h	Potion	(Quick Item)
000Ah	Ring	(Ring)
000Bh	Scroll	(Quick Item)
000Ch	Shield	(Shield)
000Dh
000Eh	Bullet	(Quiver)
000Fh	Bow	(Weapon)
0010h	Dagger	(Weapon)
0011h	Club/Mace	(Weapon)
0012h	Sling	(Weapon)
0013h	Short Sword	(Weapon)
0014h	Bastard-, Long- , 2-Handed Sword	(Weapon)
0015h	Warhammer	(Weapon)
0016h	Morning Star	(Weapon)
0017h	Flail	(Weapon)
0018h	Dart	(Weapon)
0019h	Axe 1-Handed	(Weapon)
001Ah	Staff	(Weapon)
001Bh	Crossbow	(Weapon)
001Ch
001Dh	Spear	(Weapon)
001Eh	Halbherd	(Weapon)
001Fh	Bolt	(Quiver)
0020h	Cloack	(Cloack)
0021h	Gold Piece(s)
0022h	Misc (Gems....)	(Quick Item)
0023h	Wand	(Quick Item)

 

Useability:
 

Offset	Size	Data	Type	Default Data
001Eh	0004h	Useability	4*Array Of Boolean

The Useability Field Is 4 Bytes Long And It's A Boolean Field, But I Don't Know How To Name It In Detail. Every Bit Stands For A Character Attribute. If The Bit Is Set, None Of The Characters With This Attribute Can Use The Item.

I Split The Field Up Into 4 Bytes. They Are In The Same Order As In The File.
 

Byte 01

Offset 001Eh

Bit	Data	Description
0	Chaotic	Chaotic.. (..Good/..Neutral/..Evil)
1	Evil	..Evil
2	Good	..Good
3	Neutral	..Neutral
4	Lawful	Lawful..
5	Neutral	Neutral..(..Good/..Evil) / True..(..Neutral)
6	Bard
7	Cleric

 
 

Byte 02

Offset 001Fh

Bit	Data	Description
0	Cleric/Mage	(Multiclass)
1	Cleric/Thief	(Multiclass)
2	Cleric/Ranger	(Multiclass)
3	Fighter
4	Fighter/Druid	(Multiclass)
5	Fighter/Mage	(Multiclass)
6	Fighter/Cleric	(Multiclass)
7	Fighter/Mage/Cleric	(Multiclass)

 
 

Byte 03

Offset 0020h

Bit	Data	Description
0	Fighter/Mage/Thief	(Multiclass)
1	Fighter/Thief	(Multiclass)
2	Mage
3	Mage/Thief	(Multiclass)
4	Paladin
5	Ranger
6	Thief
7	Elf

 
 

Byte 04

Offset 0021h

Bit	Data	Description
0	Dwarf
1	Half-Elf
2	Halfling
3	Human
4	Gnome
5	?
6	Druid
7	?

ItemAnimation:

this field specifies the item animation and the item appearance on the paperdoll:

ItemPrice:
 

Offset	Size	Data	Type	Default Data
0034h	0004h	ItemPrice	Longint

Contains The ItemPrice In Gold Pieces. A Price Of One GP Has To Be Writen As A 0. If It Would Be Written As A 1 Then It Might Get Rounded Down To Zero After The Multiplication With The Reputation Factor.

ItemStack:
 

Offset	Size	Data	Type	Default Data
0038h	0002h	ItemStack	Word

Contains The Number Of Items Of A Kind That Are Allowed To Be Stacked By The Player In One Inventory Field. Any Number Greater Than 0 Will Display The StackedItemsCountNumber In The Game. The System May Stack More Items Than The ItemStack Field Allows. For Example To Avoid The Display Of The StackedItemsCountNumber On Wands (Charges Of A Wand = Stacked Wands)

InventoryIcon:
 

Offset	Size	Data	Type	Default Data
003Ah	0008h	InventoryIcon	Array[0..7] Of Char

FileName Of The BAMFile That Contains The Inventory Icon.
 
 

LoreToIdentify:
 

Offset	Size	Data	Type	Default Data
0042h	0002h	LoreToIdentify	Word

Lore Needet To Identify This Item.
 
 

GroundIcon:
 

Offset	Size	Data	Type	Default Data
0044h	0008h	GroundIcon	Array[0..7] Of Char

FileName Of The BAMFile That Contains The Image Of The Item Lieing On The Ground.
 
 

ItemWeight:
 

Offset	Size	Data	Type	Default Data
004Ch	0004h	ItemWeight	Longint

Weight Of The Item.

DescriptionReference(UnIdentified):
 

Offset	Size	Data	Type	Default Data
0050h	0004h	DescriptionReference	Longint	FFFFh for none

This Is The Reference To The Description (Right Click In Inventory) Of The Unidentified Item. The Reference Is The Index Of The Description String Contained In Dialog.tlk.
 
 

DescriptionReference(Identified):
 

Offset	Size	Data	Type	Default Data
0054h	0004h	DescriptionReference	Longint	FFFFh for none

This Is The Reference To The Description (Right Click In Inventory) Of The Identified Item. The Reference Is The Index Of The Description String Contained In Dialog.tlk.
 
 

DescriptionIcon:
 

Offset	Size	Data	Type	Default Data
0058h	0008h	DescriptionIcon	Array[0..7] Of Char

FileName Of The BAMFile That Contains The Description Icon (image on the description screen).

ExtendedHeaderOffset:
 

Offset	Size	Data	Type	Default Data
0064h	0004h	ExtendedHeaderOffset	Longint

Offset Of The Extended Header Found In Weapons And Such Stuff.

ExtendedHeaderCount:
 

Offset	Size	Data	Type	Default Data
0068h	0002h	ExtdendedHeaderCount	Word

Some Item Files May Actually Contain More Than One Extended Header..
 
 

FeatureTableOffset:
 

Offset	Size	Data	Type	Default Data
006Ah	0004h	FeatureTableOffset	Longint

Offset Of The Feature Table. If No Features Available It Points To The End Of The File.
 
 

FeatureBlockCount:

Offset	Size	Data	Type	Default Data
0070h	0002h	FeatureBlockCount	Word

This Field Contains The Number Of Feature Blocks That Affect The User Of This Item.
 
 

Extended Header:

Feature:
 

Offset	Size	Data	Type	Default Data
0000h	0001h	AttackType	Byte

This field determines the type af the ability contained in the ExtendedHeader:

Target:

specifies the target of this ExtendedHeader

ProjectileType:

if the item is a projectile, this field specifies it's type:

DamageType:

this field specifies the type of the damage done:

EffectAnimation:

EffectAnimation is the animation that will start when the item's ability is used:

Feature Block:

Feature:
 

Offset	Size	Data	Type	Default Data
0000h	0002h	Feature/Effect	Word

Feature.txt
 
 

Parameter 1:
 

Offset	Size	Data	Type	Default Data
0004h	0004h	Parameter 1	Longint

Parameter 1 Is A Parameter Passed To The Feature/Effect Function. Most Time It Contains The Modification Value Of A Feature/Effect.
 
 

Parameter 2:
 

Offset	Size	Data	Type	Default Data
0008h	0004h	Parameter 2	Longint/Bitfield

Parameter 2 Is The Second Parameter Passed To The Feature/Effect Function. Most Time It Contains The Mode Of Parameter 1(%, Absolute, Relative.....).
 
 

EffectTimeMode:
 

Offset	Size	Data	Type	Default Data
000Ch	0001h	EffectTimeMode	Byte

This field sets the timemode of the item and the EffectTimeField
 

Value	Start of Effect	Duration
0	Instantly	For [EffecTime] Seconds
1	Instantly	Permanent
2	Instantly	While equiped
4	After [EffecTime] Seconds	Permanent

 

EffectTime:
 

Offset	Size	Data	Type	Default Data
000Eh	0004h	EffectTime	Longint

EffectTime Contains A Time Value For The Effect.

Game Time In Rounds = EffectTime / 60
 
 

Probability:
 

Offset	Size	Data	Type	Default Data
0012h	0002h	Probability	Word

This Field Contains The Probability This Effect To Happen. It's Value Can Go From 0 To 100.(0 The Effect Never Happens, 100 The Effect Happens Allways) The Values Grater Than 100 Are Taken As 100.
 
 

FileName:
 

Offset	Size	Data	Type	Default Data
0014h	0008h	FileName	Array[0..7] Of Char

FileName Is Another Paremeter Passed To The Effect/Feature Function. Some Functions Like Make Sound Use It To Specify The Sound File Played.
 
 

Throws:
 

Offset	Size	Data	Type	Default Data
0001Ch	0004h	Throws	Longint

This Field Only Matters For Dice Based Effects.
 
 

DiceSides:
 

Offset	Size	Data	Type	Default Data
00020h	0004h	DiceSides	Longint

This Field Only Matters For Dice Based Effects.
 
 
 
 

________________________________________________________________________

Created 30.04.99 By Thalic

Revision	Date	Comments
1.10	23.05.1999	Added AttackType
1.20	20.06.1999	Effect Block Is Now Almost Complete (Great Work ViperSting). Minor Corrections/Additions In The Descriptions.
1.21	21.06.1999	Corrected Usability And Added PaperdollItem
1.22	17.07.1999	FeatureBlockOffset Added (Info From Burton Radons) New Values Added To AttackType
1.30	13.09.1999	General Updates/Corrections/Additions
1.31	23.01.2000	Minor Corrections/Additions

This File Is Not Complete Nor Error Free (I'm Pretty Shure ;) )