GAM file format

BG2, BG2: ToB, BG:EE, BG2:EE, IWD:EE

This file format is used to hold game information in save games. The GAM file does not store area, creature or item information, instead, it stores information on the party members and the global variables which affect party members.

Overall structure:

Header

Party members

Party member CRE file data

NPCs (who are not in the party)

NPC kills statistics (embedded in NPC struct)

NPC CRE file data

Variables (in the GLOBAL namespace)

Journal entries

Familiar information

Stored Locations

Pocket Plane Locations

Familiar Extra

Offset	Size (datatype)	Description
0x0000	4 (char array)	Signature ('GAME')
0x0004	4 (char array)	Version ('V2.0')
0x0008	4 (dword)	Game time (300 units == 1 hour)
0x000c	2 (word)	Selected formation
0x000e	2 (word)	Formation button 1
0x0010	2 (word)	Formation button 2
0x0012	2 (word)	Formation button 3
0x0014	2 (word)	Formation button 4
0x0016	2 (word)	Formation button 5
0x0018	4 (dword)	Party gold
0x001c	2 (word)	Use active area from party member (0=Player1, 1=Player2, ... 5=Player6, -1=Not in party). This overrides current area at offset 0x0058.
0x001e	2 (word)	Weather bitfield bit0: Rain bit1: Snow bit2: Light Rain bit3: Medium Rain bit4: Light Wind bit5: Medium Wind bit6: Rare Lightning bit7: Lightning bit8: Storm Increasing
0x0020	4 (dword)	Offset to NPC structs for party members
0x0024	4 (dword)	Count of NPC structs for party members (including Protagonist)
0x0028	4 (dword)	Offset to party inventory
0x002c	4 (dword)	Count of party inventory
0x0030	4 (dword)	Offset to NPC structs for non-party members
0x0034	4 (dword)	Count of NPC structs for non-party members
0x0038	4 (dword)	Offset to GLOBAL namespace variables
0x003c	4 (dword)	Count of GLOBAL namespace variables
0x0040	8 (resref)	Main area
0x0048	4 (dword)	Offset to Familiar Extra
0x004c	4 (dword)	Count of journal entries
0x0050	4 (dword)	Offset to journal entries
0x0054	4 (dword)	Party reputation (*10)
0x0058	8 (resref)	Current area
0x0060	4 (dword)	GUI flags bit 0: (0) Party AI disabled / (1) Party AI enabled bit 1: Text window size* bit 2: Text window size* bit 3: Unknown bit 4: (0) Show GUI / (1) Hide GUI bit 5: (0) Show options panel / (1) Hide options panel bit 6: (0) Show portraits panel / (1) Hide portraits panel bit 7: (0) Hide automap notes / (1) Show automap notes * These bits control the text window size. The bits relate to the size as follows: 00 = Small 01 = Medium 10 = Unused 11 = Large NB. Not all engines use all bits
0x0064	4 (dword)	Loading progress 0 = Restrict XP to BG1 limit 1 = Restrict XP to TotSC limit 2 = Restrict XP to SoA limit 3 = xnewarea.2da processing to be done 3 = xnewarea.2da processing complete 5 = ToB active
0x0068	4 (dword)	Offset to familiar info
0x006c	4 (dword)	Offset to stored locations
0x0070	4 (dword)	Count of stored locations
0x0074	4 (dword)	Game time (real seconds)
0x0078	4 (dword)	Offset to pocket plane locations
0x007c	4 (dword)	Count of pocket plane locations
0x0080	4 (dword)	EE: Zoom level (in percent), 0 or 100: default zoom level, >100: zoomed out, <100: zoomed in.
0x0084	8 (resref)	EE: Random encounter area set by script action ForceRandomEncounter() or ForceRandomEncounterEntry().
0x008c	8 (resref)	EE: Current worldmap
0x0094	8 (char array)	EE: Current campaign (e.g. "SOD" for Siege of Dragonspear)
0x009c	4 (dword)	EE: Familiar owner (0=Player1, 1=Player2, ..., 5=Player6), used in IWDEE
0x00a0	20 (char array)	EE: Random encounter entry set by script action ForceRandomEncounterEntry().

Offset	Size (datatype)	Description
0x0000	2 (word)	Character selection 0 = Not selected 1 = Selected 0x8000 = Dead
0x0002	2 (word)	Party order (0x0-0x5 = PlayerXFill, 0xFFFF = not in party)
0x0004	4 (dword)	Offset (from start of file) to CRE resource data for this character
0x0008	4 (dword)	Size of CRE resource data for this character
0x000c	8 (bytes)	Character Name
0x0014	4 (dword)	Character orientation
0x0018	8 (resref)	Characters current area
0x0020	2 (word)	Character X coordinate
0x0022	2 (word)	Character Y coordinate
0x0024	2 (word)	Viewing rectangle X coordinate
0x0026	2 (word)	Viewing rectangle Y coordinate
0x0028	2 (word)	Modal action
0x002a	2 (word)	Happiness
0x002c	4 (dword)	NumTimesInteracted NPC count (unused)
0x0030	4 (dword)	NumTimesInteracted NPC count (unused)
0x0034	4 (dword)	NumTimesInteracted NPC count (unused)
0x0038	4 (dword)	NumTimesInteracted NPC count (unused)
0x003c	4 (dword)	NumTimesInteracted NPC count (unused)
0x0040	4 (dword)	NumTimesInteracted NPC count (unused)
0x0044	4 (dword)	NumTimesInteracted NPC count (unused)
0x0048	4 (dword)	NumTimesInteracted NPC count (unused)
0x004c	4 (dword)	NumTimesInteracted NPC count (unused)
0x0050	4 (dword)	NumTimesInteracted NPC count (unused)
0x0054	4 (dword)	NumTimesInteracted NPC count (unused)
0x0058	4 (dword)	NumTimesInteracted NPC count (unused)
0x005c	4 (dword)	NumTimesInteracted NPC count (unused)
0x0060	4 (dword)	NumTimesInteracted NPC count (unused)
0x0064	4 (dword)	NumTimesInteracted NPC count (unused)
0x0068	4 (dword)	NumTimesInteracted NPC count (unused)
0x006c	4 (dword)	NumTimesInteracted NPC count (unused)
0x0070	4 (dword)	NumTimesInteracted NPC count (unused)
0x0074	4 (dword)	NumTimesInteracted NPC count (unused)
0x0078	4 (dword)	NumTimesInteracted NPC count (unused)
0x007c	4 (dword)	NumTimesInteracted NPC count (unused)
0x0080	4 (dword)	NumTimesInteracted NPC count (unused)
0x0084	4 (dword)	NumTimesInteracted NPC count (unused)
0x0088	4 (dword)	NumTimesInteracted NPC count (unused)
0x008c	2 (word)	Index into slots.ids for Quick Weapon 1 (0xFFFF = none)
0x008e	2 (word)	Index into slots.ids for Quick Weapon 2 (0xFFFF = none)
0x0090	2 (word)	Index into slots.ids for Quick Weapon 3 (0xFFFF = none)
0x0092	2 (word)	Index into slots.ids for Quick Weapon 4 (0xFFFF = none)
0x0094	2 (word)	Quick weapon slot 1 ability (0/1/2 or -1 disabled)
0x0096	2 (word)	Quick weapon slot 2 ability (0/1/2 or -1 disabled)
0x0098	2 (word)	Quick weapon slot 3 ability (0/1/2 or -1 disabled)
0x009a	2 (word)	Quick weapon slot 4 ability (0/1/2 or -1 disabled)
0x009c	8 (resref)	Quick Spell 1 resouce
0x00a4	8 (resref)	Quick Spell 2 resouce
0x00ac	8 (resref)	Quick Spell 3 resouce
0x00b4	2 (word)	Index into slots.ids for Quick Item 1 (0xFFFF = none)
0x00b6	2 (word)	Index into slots.ids for Quick Item 2 (0xFFFF = none)
0x00b8	2 (word)	Index into slots.ids for Quick Item 3 (0xFFFF = none)
0x00ba	2 (word)	Quick Item 1 slot ability (0/1/2 or -1 disabled)
0x00bc	2 (word)	Quick Item 2 slot ability (0/1/2 or -1 disabled)
0x00be	2 (word)	Quick Item 3 slot ability (0/1/2 or -1 disabled)
0x00c0	32 (bytes)	Name
0x00e0	4 (dword)	Talkcount
0x00e4	116 bytes	character stats for this character
0x0158	8 bytes	Voice Set

Offset	Size (data type)	Description
0x0000	4 (strref)	"Most powerful vanquished" - Name
0x0004	4 (dword)	"Most powerful vanquished" - XP Reward
0x0008	4 (dword)	Time in party (1/15 seconds)
0x000c	4 (dword)	Time Joined (1/15 seconds)
0x0010	1 (byte)	Party member (0 = Not in party, 1 = In party)
0x0011	2 (word)	Unused
0x0013	1 (byte)	First letter of CRE resref (changed to *)
0x0014	4 (dword)	Kills - XP Gained (chapter)
0x0018	4 (dword)	Kills - Number (chapter)
0x001c	4 (dword)	Kills - XP (game)
0x0020	4 (dword)	Kills - number (game)
0x0024	4*8 (resref array)	Favourite spells
0x0044	4*2 (word array)	Favourite spell count
0x004c	4*8 (resref array)	Favourite weapons
0x006c	4*2 (word)	Favourite weapon time (time equipped in combat - 1/15 seconds)

Note the format specification allows variables of differing types, however the engine implementation only reads and writes INT variables.

Offset	Size (data type)	Description
0x0000	32 (char array)	Variable name
0x0020	2 (type)	Type bit 0: int bit 1: float bit 2: script name bit 3: resref bit 4: strref bit 5: dword
0x0022	2 (word)	Ref value
0x0024	4 (dword)	Dword value
0x0028	4 (dword)	Int value
0x002c	8 (double)	Double value
0x0034	32 (char array)	Script name value

This section stores the strref, chapter and time for any entry added to the journal.

Offset	Size (data type)	Description
0x0000	4 (strref)	Journal text
0x0004	4 (dword)	Time (seconds)
0x0008	1 (byte)	Current chapter number
0x0009	1 (byte)	Read by character x
0x000a	1 (byte)	Journal section bit 0: Quests bit 1: Competed quest bit 2: Journal Info NB. If no bits are set, the entry is a user-note
0x000b	1 (byte)	Location flag (0x1F = external TOT/TOH, 0xFF = internal TLK)

The familiar (summoned by the Find Familiar spell) is dependent on the alignment of the caster. This section contains the mapping between caster alignment and the CRE file to summon.

Offset	Size (data type)	Description
0x0000	8 (resref)	Lawful Good Familiar
0x0008	8 (resref)	Lawful Neutral Familiar
0x0010	8 (resref)	Lawful Evil Familiar
0x0018	8 (resref)	Neutral Good Familiar
0x0020	8 (resref)	Neutral Familiar
0x0028	8 (resref)	Neutral Evil Familiar
0x0030	8 (resref)	Chaotic Good Familiar
0x0038	8 (resref)	Chaotic Neutral Familiar
0x0040	8 (resref)	Chaotic Evil Familiar
0x0048	4 (dword)	Offset to familiar resources
0x004c	4 (dword)	LG level 1 familiar count
0x0050	4 (dword)	LG level 2 familiar count
0x0054	4 (dword)	LG level 3 familiar count
0x0058	4 (dword)	LG level 4 familiar count
0x005c	4 (dword)	LG level 5 familiar count
0x0060	4 (dword)	LG level 6 familiar count
0x0064	4 (dword)	LG level 7 familiar count
0x0068	4 (dword)	LG level 8 familiar count
0x006c	4 (dword)	LG level 9 familiar count
0x0070	4 (dword)	LN level 1 familiar count
0x0074	4 (dword)	LN level 2 familiar count
0x0078	4 (dword)	LN level 3 familiar count
0x007c	4 (dword)	LN level 4 familiar count
0x0080	4 (dword)	LN level 5 familiar count
0x0084	4 (dword)	LN level 6 familiar count
0x0088	4 (dword)	LN level 7 familiar count
0x008c	4 (dword)	LN level 8 familiar count
0x0090	4 (dword)	LN level 9 familiar count
0x0094	4 (dword)	CG level 1 familiar count
0x098	4 (dword)	CG level 2 familiar count
0x009c	4 (dword)	CG level 3 familiar count
0x0100	4 (dword)	CG level 4 familiar count
0x0104	4 (dword)	CG level 5 familiar count
0x0108	4 (dword)	CG level 6 familiar count
0x010c	4 (dword)	CG level 7 familiar count
0x0110	4 (dword)	CG level 8 familiar count
0x0114	4 (dword)	CG level 9 familiar count
0x0118	4 (dword)	NG level 1 familiar count
0x011c	4 (dword)	NG level 2 familiar count
0x0120	4 (dword)	NG level 3 familiar count
0x0124	4 (dword)	NG level 4 familiar count
0x0128	4 (dword)	NG level 5 familiar count
0x012c	4 (dword)	NG level 6 familiar count
0x0130	4 (dword)	NG level 7 familiar count
0x0134	4 (dword)	NG level 8 familiar count
0x0138	4 (dword)	NG level 9 familiar count
0x013c	4 (dword)	TN level 1 familiar count
0x0140	4 (dword)	TN level 2 familiar count
0x0144	4 (dword)	TN level 3 familiar count
0x0148	4 (dword)	TN level 4 familiar count
0x014c	4 (dword)	TN level 5 familiar count
0x0150	4 (dword)	TN level 6 familiar count
0x0154	4 (dword)	TN level 7 familiar count
0x0158	4 (dword)	TN level 8 familiar count
0x015c	4 (dword)	TN level 9 familiar count
0x0160	4 (dword)	NE level 1 familiar count
0x0164	4 (dword)	NE level 2 familiar count
0x0168	4 (dword)	NE level 3 familiar count
0x016c	4 (dword)	NE level 4 familiar count
0x0170	4 (dword)	NE level 5 familiar count
0x0174	4 (dword)	NE level 6 familiar count
0x0178	4 (dword)	NE level 7 familiar count
0x017c	4 (dword)	NE level 8 familiar count
0x0180	4 (dword)	NE level 9 familiar count
0x0184	4 (dword)	LE level 1 familiar count
0x0188	4 (dword)	LE level 2 familiar count
0x018c	4 (dword)	LE level 3 familiar count
0x0190	4 (dword)	LE level 4 familiar count
0x0194	4 (dword)	LE level 5 familiar count
0x0198	4 (dword)	LE level 6 familiar count
0x019c	4 (dword)	LE level 7 familiar count
0x0200	4 (dword)	LE level 8 familiar count
0x0204	4 (dword)	LE level 9 familiar count
0x0208	4 (dword)	CN level 1 familiar count
0x020c	4 (dword)	CN level 2 familiar count
0x0210	4 (dword)	CN level 3 familiar count
0x0214	4 (dword)	CN level 4 familiar count
0x0218	4 (dword)	CN level 5 familiar count
0x021c	4 (dword)	CN level 6 familiar count
0x0220	4 (dword)	CN level 7 familiar count
0x0224	4 (dword)	CN level 8 familiar count
0x0228	4 (dword)	CN level 9 familiar count
0x022c	4 (dword)	CE level 1 familiar count
0x0230	4 (dword)	CE level 2 familiar count
0x0234	4 (dword)	CE level 3 familiar count
0x0238	4 (dword)	CE level 4 familiar count
0x023c	4 (dword)	CE level 5 familiar count
0x0240	4 (dword)	CE level 6 familiar count
0x0244	4 (dword)	CE level 7 familiar count
0x0248	4 (dword)	CE level 8 familiar count
0x024c	4 (dword)	CE level 9 familiar count

This struct is filled by the StorePartyLocations() action and cleared by the RestorePartyLocations() action. There is one record for each member of the party at the time the action was called.

Offset	Size (data type)	Description
0x0000	8 (resref)	Area
0x0008	2 (word)	X coordinate
0x000a	2 (word)	Y coordinate

This struct is filled by the Spell Effect: Area Switch [298] effect and cleared by the ExitPocketPlane effect. There is one record for each member of the party at the time the effect was called.

Offset	Size (data type)	Description
0x0000	8 (resref)	Area
0x0008	2 (word)	X coordinate
0x000a	2 (word)	Y coordinate

This is a table of resefs related to familiars. The table count is the sum of the level entries in the familiar section.

Offset	Size (data type)	Description
...	8 (resref)	Familiar resref