OBDATA.DAT

OBDATA.DAT is found in GEODATA and contains general information on objects found in the game, such as their accuracy and weight. It also contains template information regarding clip size; to hack dynamic Battlescape info on the number of rounds left in a particular item in play (or it's location etc), see OBPOS.DAT.

There are 80 records, each of which are 54 bytes long (a total of 4,320 bytes).

There are 33 entries for corpses (or otherwise destroyed robots and vehicles), four per large unit, one per small unit. Furthermore there are 41 "object" entries (weapons etc) and 6 obsolete/unused entries (mostly unusable, and without valid name pointers in the executable).

Values are presented in bold, according to the offsets in each record (0 to 53).

Note: If you hack OBDATA, you can have the game reload the data by entering or exiting the battlescape mode. This is true for the DOS version of X-Com (which switches between executables at these points), but the WinCE version may need to be entirely restarted.

Structure

0-19[0x0~0x13]: Name of object. Delimited by a null character. These are internal names... they all make sense, but are not the standardized names displayed in the game. Names and IDs (reference lookup numbers, including within OBDATA - see e.g. [26] to [28]):

Index	Object	Index	Object	Index	Object
00/x00	PISTOL	27/x1B	Flare	54/x36	Floater Corpse
01/x01	PISTOL CLIP	28/x1C	empty	55/x37	Celatid Corpse
02/x02	RIFLE	29/x1D	empty	56/x38	Silacoid Corpse
03/x03	RIFLE CLIP	30/x1E	empty	57/x39	Chryssalid Corpse
04/x04	HEAVY CANNON	31/x1F	CORPSE	58/x3A	reaper corpse 1
05/x05	CANNON AP-AMMO	32/x20	CORPSE & ARMOUR	59/x3B	reaper corpse 2
06/x06	CANNON HE-AMMO	33/x21	CORPSE & POWER SUIT	60/x3C	reaper corpse 3
07/x07	CANNON I-AMMO	34/x22	Heavy Plasma	61/x3D	reaper corpse 4
08/x08	AUTO-CANNON	35/x23	Heavy Plasma Clip	62/x3E	cyber 1
09/x09	AUTO-CANNON AP-AMMO	36/x24	Plasma Rifle	63/x3F	cyber 2
10/x0A	AUTO-CANNON HE-AMMO	37/x25	Plasma Rifle Clip	64/x40	cyber 3
11/x0B	AUTO-CANNON I-AMMO	38/x26	Plasma Pistol	65/x41	cyber 4
12/x0C	ROCKET LAUNCHER	39/x27	Plasma Pistol Clip	66/x42	secto 1
13/x0D	SMALL ROCKET	40/x28	BLASTER LAUNCHER	67/x43	secto 2
14/x0E	LARGE ROCKET	41/x29	BLASTER BOMB	68/x44	secto 3
15/x0F	INCENDIARY ROCKET	42/x2A	SMALL LAUNCHER	69/x45	secto 4
16/x10	LASER PISTOL	43/x2B	STUN MISSILE	70/x46	hover 1
17/x11	LASER GUN	44/x2C	ALIEN GRENADE	71/x47	hover 2
18/x12	HEAVY LASER	45/x2D	ELERIUM-115	72/x48	hover 3
19/x13	GRENADE	46/x2E	MIND PROBE	73/x49	hover 4
20/x14	SMOKE GRENADE	47/x2F	>>UNDEFINED <<	74/x4A	TANK1
21/x15	PROXIMITY GRENADE	48/x30	>> empty <<	75/x4B	TANK 2
22/x16	HIGH EXPLOSIVE	49/x31	>> empty <<	76/x4C	TANK 3
23/x17	MOTION SCANNER	50/x32	Sectoid Corpse	77/x4D	TANK 4
24/x18	MEDI-KIT	51/x33	Snakeman Corpse	78/x4E	CIVM
25/x19	PSI-AMP	52/x34	Ethereal Corpse	79/x4F	CIVF
26/x1A	STUN ROD	53/x35	Muton Corpse

The names as displayed in battle are stored in ENGLISH2.DAT, FRENCH2.DAT and GERMAN2.DAT, hence allowing them to appear in multiple languages. The exact pointers as to which item has which name are stored in TACTICAL.EXE.

20[0x14]: BIGOBS.PCK reference (pointer to graphic for inventory)

21[0x15]: FLOOROB.PCK reference (pointer to graphic for item on ground)

22[0x16]: Average Weapon Strength (Same as seen in UFOpaedia). For clip based weapons, this applies to the clip and not the weapon itself. Also note that if set to 0 the weapon will still "shoot" and the shot can still "hit", registering with the hit counter at UNITREF.DAT[81] and making an easy way to avoid any damage while testing (if so desired).

Note that a (non-explosive) weapon will hit for between 0 and this*2 damage with each shot. For example, if you set it to 100, the weapon will deal between 0 and 200 points each time it is fired.

For information on hacking explosives vs. their blast diameters and strength, see this. It includes what happens if you change the Stun Bomb to HE.

23[0x17]: Display priority for when items are in a stack. The highest value here determines which will be rendered in the battlescape. In the case of a tie, the lowest ObPos record number wins.

24[0x18]: Inventory X Size (width)

25[0x19]: Inventory Y Size (height)

26-28[0x1A~1C]: Look-up within OBDATA for ammo this weapon uses. Up to three types possible; 255 for no (more) ammo. Note that ammo always directly follows its weapon in this file.

29[0x1D]: HANDOB.PCK Image of item when held in a units's hands in the battlescape view.

30[0x1E]: Often corresponds to 29, but does not appear to be used. Called "graphics type firing" by the game. Is this the shot graphic to use for the weapon?

31[0x1F]: Ammo Damage Type

  0 AP
  1 IN
  2 HE
  3 Laser
  4 Plasma
  5 Stun
  6 Melee
  7 Acid Spit (from Celatid)
255 Not Ammo

32[0x20]: Accuracy, Auto

33[0x21]: Accuracy, Snap

34[0x22]: Accuracy, Aimed

Percent TUs are rounded down (truncated). In an extreme case, if you hack UNITREF.DAT[25] (Base TUs) to 199 and Percent TUs to 1, you will need 1 TU to fire the weapon (and can make 199 shots per turn). Or to really make things interesting, set Base TUs to 99 and Percent TUs to 1 - now it takes zero TUs! Also, it relies on Base TUs, not current TUs, so if you e.g. put Base TUs at 99, Percent TUs at 1 (0 TUs per shot), and Current TUs at 255, you still get 255 TUs, with 0 TUs per shot, for the turn you load that savegame - excellent if you plan on reloading it for each round of testing.

Don't set Percent TUs to 0. If you do, the object is no longer considered a weapon, and can only be thrown.

35[0x23]: Percent TUs Used, Auto

36[0x24]: Percent TUs Used, Snap

37[0x25]: Percent TUs Used, Aimed

38[0x26]: Primary use: Clip Size (for ammo; see [49]). Secondary use: Melee weapon strength, as follows:

  0 All Corpses/Electroflare/Mind probe
  8 Pistol
 65 Stun Rod
 10 Everything else...

Tertiary use: Turn detonation condition for "grenade" objects, but is otherwise unused. If the Grenade ([44]) and the 'is ammo?' ([49]) fields are set to true, this will create an explosive that is pre-armed to go off at a turn designated by this field. A side effect is that the grenade object will show an ammo count with this field's value.

39[0x27]: Melee damage type

  0 AP
  1 IN
  2 HE
  3 Laser or Gauss
  4 Plasma or Sonic
  5 Stun
  6 TFTD vibroblade damage (does not appear to be used in UFO)
  7 TFTD Electric damage (Bio Drone?)

40[0x28]: Melee Accuracy. Zombie found that changing this does not change the Stun Rod's 100% accuracy (nor does changing soldier Melee Accuracy). Thus the Stun Rod appears to be hard-wired to 100% for UFO, but in TFTD it is a valid and effective variable. (TFTD uses much more melee than UFO.)

  0 All Corpses
  0 Electroflare
  0 Plasma Weapon Clips
100 Everything else...

41[0x29]: TU% cost when attacking as a melee weapon

 50 Most objects
 30 Stun rod
 40 TFTD thermal tazer
 10 Vibroblade
 15 Thermal lance
 20 Heavy thermal Lance
  0 All Corpses
  0 Electroflare
  0 Plasma Weapon Clips

So a summary of 39 to 41 looks like this:

  39   40   41   Objects
   0    0    0   All Corpses/Plasma Pistol Clip
   5  100   30   Stun Rod
   8    0    0   Plasma Rifle Clip/Heavy Plasma Clip/Electroflare
   9  100   50   Pistol/Pistol Clip

   8  100   50   Everything else... (34 objects)

42[0x2A]: Explosive strength needed to destroy object. AKA "Constitution".

43[0x2B]: Item Weight, used for both throwing and encumbrance purposes.

44[0x2C]: Grenade Type

1   Standard explosive grenade
2   Proximity Grenade
3   Smoke Grenade
4-7 Gas - probably unused.

45[0x2D]: Value (or "priority") to the AI of picking up this weapon.

This field used as AI "worth to take" estimation flag, and only when it's >5. By accident or by design, it was not implemented. However this can be easily implemented by setting values above 5. This would have the benefit of making Aliens smarter after they lose their weapons or run out of ammo. See the talk section of this page: Talk:OBDATA.DAT#Field_0x2D_.2845.29

46[0x2E]: Boolean: Is Weapon That Shoots? (AKA Is Ranged Weapon)?

47[0x2F]: Boolean: Is Weapon? (AKA Close Combat Weapon)?

48[0x30]: Boolean: Is Non-Waypoint Weapon? (AKA Is Ranged Combat Weapon)?

49[0x31]: Boolean: Is Ammo?

50[0x32]: Boolean: Is Two-Handed Weapon? (AKA Is Large Weapon/Object)?

51[0x33]: Boolean: Is Blaster Launcher? (AKA Weapon Fires Guided Missile)?

52[0x34]: Boolean: Is Alien? (AKA Is Alien Artefact)?

53[0x35]: Scoring points (except for Elerium which works per 50 units). (AKA Victory Points for recovery).

Extra Notes

Unique Objects

Certain unique objects have "unique" features that are assigned to them. These are:

• Motion Scanner - can access motion scanner panel
• Medikit - brings up medikit panel
• Flare - will cast light around its object if on ground whenever the light level of the map is updated, such as when throwing a flare or when walking.
• Stun Rod - only weapon that can access its melee attack
• Mind Probe - can probe enemies
• Psi Amp - can access two different psi attacks
• Elerium - adds 50 units of elerium to storage at end of battle

TFTD's equivalents are same but also add the three drill weapons as melee weapons.

These properties are not configured in obdata.dat, but are instead defined by the game executable. Copying the stun rod info to a different record number results in an item which can't be used to zap things.

One way around the melee command limitation is to stack two or more items in your soldiers hands (via hacking) - The action menu will then display a combination of both items abilities. This allows you to bludgeon things with a plasma rifle (for example).

Laser Weapons

Laser weapons use no clips, but can still be fired. To give similar properties to other weapons you must remove their ammo type indexes (set offsets [26]-[28] to 255), give the weapon a valid damage type (set offset [31] to a value from 0-7), and give the weapon a power rating (set offset [22] to the average you want the weapon to deal). All the usual flags for standard firearms apply.

Grenades

Grenades are similar to laser weapons in that the object's power (offset[22]) and damage type (offset[31]) must be set. In addition, to complete the object as a grenade, the Grenade type (offset[44]) must also be set to standard (1), proximity (2) or smoke (3) in order for the item to be turned into an object that can be primed.

Be aware that regardless of the damage type entered, it will default to HE.

Any object that's not functioning as a gun or as ammo can be turned into a grenade of some description.

Note that if you set the Is Ammo? (offset[49]) field to true, the grenade will be pre-armed at the start of the battle to explode after the turn specified in offset[38], which is normally used for ammo count or melee attack strength. The grenade will also gain an ammo-count display on it with the value in offset[38].

One practical application of this is to create exploding elerium pods that will explode after a pre-set number of turns. For example, setting offset[38] to 40, and by the time you reach turn 20, any elerium pods that have not been destroyed or picked up will explode. Set the damage to strength to something insignificant like 1 to let them wink out of existence, or up to 255 for violent explosions.

Guided Weapons

The flag in Offset[51] controls whether the object fires a way-point guided projectile. Projectiles fired by this weapon will also default to HE damage.

Once set, the flag overrides various obdata.dat settings. Firing costs will default to 60% while the accuracy of the projectile will not be influenced by the user's base accuracy.

See Also

• OBPOS.DAT - Stores positions of objects in a battlescape
• PRODUCT.DAT - Stores information on manufactuable items (Hours, Cost, etc.)
• PURCHASE.DAT - Stores buying and selling Information about most of these items
• UP.DAT - References items in this file for the UFOpaedia
• GEODATA - Parent Folder for file
• Saved Game Files