Notes:Magic Carpet (DOS)

This page contains notes for the game Magic Carpet (DOS).

Level.Dat Data Structures

Included with the files of the original CD release of Magic Carpet is a file called GAM00088.DAT. This is an invaluable and interesting file for reverse engineering as it's some kind of internal format used to save the details of an unfinished map. Specifically, this seems to be the raw contents of the map LEV00088.DAT, based on the corresponding .inf file for that cut level (which made it into the game as level 65).

What's so useful is that the map includes headers for the data, therefore naming each attribute. Just as importantly, it also lists the map generator parameters. Magic Carpet is interesting, as while it includes the "MAPHACK" tool to generate height map levels out of user pictures, the game does NOT store height maps in the final levels. In fact they are all procedurally generated on runtime from a set of parameters stored in the level file. Note all levels are of a fixed size (38KB), and pad out any unused space with zero byte entries.

Map Header and Generation Parameters

These begin from the very first byte of each level file up to position 2e. Names are mostly from GAM00088.DAT file, which only begins from the Seed attribute. Note most of the later attributes only seem to work with one byte, higher values seem to crash the game (like rivers).

Variable	Offset (hex)	Length (hex)	Notes
Level Mana Total	0x0	0x4	The level's total mana. Note this works in conjunction with the target percentage set at the end of the file.
Seed	0x4	0x2	Determines the fundamental map landscape shape
Blank	0x6	0x2
Off[set]	0x8	0x2	Offsets the generated landscape horizontally within the map frame
Blank	0xA	0x2
Raise	0xC	0x4	Raises height of landscape peaks
Gnarl	0x10	0x2	Gnarls landscape to create tree root style appearance. Rarely used
Blank	0x12	0x2
River	0x14	0x2	Generates more rivers on the map. Values above 255 seem to crash the game
Blank	0x16	0x2
Sourc	0x18	0x2	Seems to raise sea level/lower base level of terrain. While this seems to use two bytes, going beyond the first byte seems to crash the game
Blank	0x1A	0x2
SnLin	0x1C	0x2	Always C8/200. Not sure what it does
Blank	0x1E	0x2
SnFlt	0x20	0x2	Generally low number below 50. Unknown what this does
Blank	0x22	0x2
BhLin	0x24	0x2	Beach Line? Generally number below 30. This determines how desertified the level is - how much of the terrain is "beach". 255 is pretty much entirely sand.
Blank	0x26	0x2
BhFlt	0x28	0x2	Values generally below 20. Presumably beach related, but not apparent what this actually does
Blank	0x2A	0x2
RkSte	0x2C	0x2	Unknown. Values generally below 40

There is then a lots of zeroed data until position 442. This seems to be fixed across all levels as the start of Thing data.

Thing Definitions

These always begin at position 442 in a level file. These include everything the player can see and interact with in the game, from enemies to collectables to switches. Each entry is 18 bytes long, and there are 1999 entries.

To do: Fill this out, Michael Howard's work here already collects 99% of it

Variable	Offset (hex)	Length hex)	Notes
Class	0x0	0x2	What type of thing it is - enemy, scenery, etc
Model	0x1	0x2	Sub type. Which enemy type, what kind of scenery, etc
Xpos	0x3	0x2	X coordinate of Thing
Ypos	0x4	0x2	Y coordinate of Thing
DisId	0x6	0x2	Distinct ID? Used by switches, needs more research
SwiSz	0x8	0x2	Switch Size - the size of the area in which the player must enter to trigger the switch
SwiId	0xA	0x2	The switch number that this item is triggered by. Also used as a modifier for other values, for example what kind of spell
Paren	0xC	0x2	Joins together linked items, like segments of path and walls. Also used by teleports to store the X value of the destination. Also used as a modifier to e.g. determine what kind of building to place
Child	0xE	0x2	Joins together linked items, like segments of path and walls. Also used by teleports to store the Y value of the destination

Each entry contains the above variables. Each entry is numbered 1 - 1999, but this is implicit from their order and used for things like the Parent and Child values, it's not explicitly recorded in the entry.

Thing Types

These go in the "Class" field. They define the basic Type of a Thing

Value	Type	Notes
02	Scenery
03	Player Spawn
05	Creatures
07	Weather
0A	Effects
0B	Switches
0C	Spells

Once a Thing type is set, the Thing Subtype (e.g. if a creature, what kind of creature it is) is then set in the "Model" field:

Scenery Thing SubTypes

Value	Thing Subtype	Notes
00	Tree	There are two types of tree used in the game. It doesn't seem possible to choose which is used where, they are set pseudo-randomly (as they use a seed they will always be the same choice when the level is loaded)
01	Standing Stone
02	Dolmen
03	Bad Stone	The weird looking stone with the kind of witch creature statue carved into it
04	Blue Dome	A leftover from when the game used 2D billboard textures for buildings. Not used in any final game levels
05	Blue Dome	Duplicate of above

Player Spawn Subtypes

These are wizard (player) start positions. If the wizard (other than the player) has a castle level set above zero, they will build their castle here on level start

Value	Thing Subtype	Notes
04	Flyer1	The player
05	Flyer2
06	Flyer3
07	Flyer4
08	Flyer5
09	Flyer6
0A	Flyer7
0B	Flyer8

Creature Thing Subtypes

Creatures with a SwiId value are spawned by triggering the switch with the corresponding SwiId value

Value	Thing Subtype	Notes
00	Dragon
01	Vulture
02	Bee
03	Worm
04	Archer
05	Crab
06	Kraken
07	Troll/Ape	It turns out there is a random chance for either of these enemies to appear using this Creature ID.
08	Griffin
09	Skeleton
0A	Emu
0B	Genie
0C	Builder
0D	Townie
0E	Trader
10	Wyvern

Weather Thing Subtypes

The weather code seems to be totally removed from the game, and none of the values do anything.

Value	Thing Subtype	Notes
0	Tornado
1	Rain Cloud
2	Thunder Cloud
3	Thermals
4	Wind	This remains in a few multiplayer levels but does nothing

Effect Thing Subtypes

"Effects" range from all objects that are not creatures or scenery (buildings, Craters, walls, etc) to one-off effects like explosions and traps usually triggered by switches

Value	Thing Subtype	Notes
0	Explosion
1	Big explosion
2	Dust
3	Blood
4	Spark
5	Splash
6	Fire
7	Freeze
8	Mini Volcano
9	Volcano
0A	Mini crater
0B	Crater
0C	Possession
0D	White smoke
0E	Black smoke
0F	Earthquake
11	Meteor
15	Steal Mana	Trap
17	Lightning
18	Rain of Fire
19	Unknown
1C	Wall	Always have a DisID of 65535 and SwiId of 1. They work by having a minimum of two points (Things) defined in the level and linked via the Parent and Child values (based on their Thing number in the list) to draw the wall to fit between the points.
1D	Path	Works exactly the same as Walls above
1F	Canyon	Again, works exactly the same as Walls do
22	Teleport	Uses the Parent field to store the X coordinate of its destination, and the Child field for its destination's Y coordinate
27	Mana Ball	These start as a single small ball with a value of 512 mana. To get bigger values, more small balls are placed on the same point, and they will auto-merge into a larger size on level start.
2D	Villager Building	The Parent field value determines building type. 1 = Tent, various other values determine other building types
31	Unknown
32	Ridge Node	Again, works exactly the same as Walls do
34	Crab Egg

Switch Thing Subtypes

Switches cause either Effects to trigger, or Creatures/spells to spawn. The SwiId (Switch ID) field is used to give each switch a unique ID, and also to assign Effects and Creature spawns to trigger by giving them the same ID. However, there is more at play, the DisId field is also used to trigger switches in sequence (so they will only trigger after the previously linked switch in that attribute has been fired). Switch areas are always circular, and the SwiSz (Switch Size) field determines the radius of this circle. Things that are to be triggered by a switch need the SwiId and DisId set to that of the switch. If both are not set, the object will start the level already spawned.

Value	Type	Notes
0	Hidden Inside	A hidden switch activated once by the player moving inside its area
1	Hidden outside	A hidden switch activated once by the player moving outside its area
2	Hidden Inside re	A recurring/repeatable hidden switch activated by the player moving inside its area.
3	Hidden outside re	A recurring/repeatable hidden switch activated by the player moving outside its area.
4	On victory	This switch type triggers when the player completes the level (i.e. hit mana target). Levels 20 and 22 use this.
5	Death Inside	The "Death" switch types don't actually do anything special. They work exactly the same as regular hidden switches. The intention is that these are two be used when the outcome of the switch will be bad for the player (i.e. can make them dead!) so that it is obvious that is what the switch is for in the editor. An example of this is LEV00025 - lots of Death traps that trigger lethal meteor storms.
6	Death Outside
7	Death inside re
8	Death Outside re
9	Obvious Inside	A visible switch that triggers by the player moving inside its area. Note, this and all obvious type switches shows a small X at its centre
0A	Obvious outside	A visible switch that triggers by the player moving outside its area
0B	Obvious Inside re	A repeatable visible switch that triggers by the player moving inside its area
0C	Obvious outside re	A repeatable visible switch that triggers by the player moving outside its area
0D	Dragon	These "creature" switches trigger once all creatures of their respective type on the map have been killed.
0E	Vulture
0F	Bee
10	Worm
11	Archer
12	Crab
13	Kraken
14	Troll
15	Griffon
18	Genie
1D	Wyvern
1E	Creature all	Triggers once all creatures of all types on the map have been killed
1F	Exit Level	LEV000049 Uses this switch type, it marks the final level of the game

Spell Thing SubTypes

Spell jars. Note that these MUST have the SwiId value populated to tell the game which type of spell it is, or the player cannot pick up the item. There seem to be two accepted values: 1 for normal spell jar (red) and 5 for the non-mana-limited (blue) variety. If a spell jar is spawned by a switch, the DisId field is used to mark which one it is, NOT the SwiId field (which still marks what kind of jar it is).

Value	Type	Notes
0	Fireball
1	Heal
2	Speed Up
3	Possession
4	Shield
5	Beyond Sight
6	Earthquake
7	Meteor
8	Volcano
9	Crater
0A	Teleport
0B	Duel	Called "Rubber band" internally
0C	Invisible
0D	Steal Mana
0E	Rebound
0F	Lightning
10	Castle
11	Skeleton
12	Thunderbolt
13	Mana Magnet
14	Fire Wall
15	Reverse Speed
16	Global Death	Called "Smart Bomb" internally
17	Rapid Fireball	Called "Mini Fireball" internally

Wizard Stats Block

These are always in the same place in the file, starting at position 90D4. The first 12 bytes are actually the APR stats for the player... Which unless you're some kind of robot, don't have any effect.

Player Spells

Player spells are defined at 90E0. There are 24 bytes, each one simply a boolean value for a spell. There does seem to be some logic involved in which spells are unlocked, however (some seem to need e.g. castle unlocked first).

Spell	Offset (hex)	Length hex)	Notes
Fireball	0x0	0x1	All are booleans, 1 = character has this spell
Shield	0x1	0x1
Accelerate	0x2	0x1
Possession	0x3	0x1
Health	0x4	0x1
Beyond Sight	0x5	0x1
Earthquake	0x6	0x1
Meteor	0x7	0x1
Volcano	0x8	0x1
Crater	0x9	0x1
Teleport	0xA	0x1
Duel	0xB	0x1
Invisible	0xC	0x1
Steal Mana	0xD	0x1
Rebound	0xE	0x1
Lightning	0xF	0x1
Castle	0x10	0x1
Undead Army	0x11	0x1
Lightning Storm	0x12	0x1
Mana Magnet	0x13	0x1
Wall of Fire	0x14	0x1
Reverse Acceleration	0x15	0x1
Global Death	0x16	0x1
Rapid Fireball	0x17	0x1

Enemy Wizard Definitions

After the above, there is a block of 100 bytes of what is usually 01 for each wizard. These actually seem to be Boolean values for what appears to be which tactics this particular wizard will use in the level. Most of the time these are all enabled, but on some earlier levels some are set to 00, which seems to be how to dumb down the AI in how it fights the player. It's not known what each specific value does.

Five Bytes after this are the definitions for that wizard's Aggression, Perception, and Reflexes stats, as explained in the Official Strategy Guide. While they can range from 0 - 255 as explained in the guide, the baseline default for all is actually 128.

The fourth byte after the Reflex value is the start of the spell loadout for the wizard, which works exactly as per the player's spells, listed above.

Attribute	Offset (hex)	Length (hex)	Notes
Aggression	0x0	0x1
Blank	0x1	0x4
Perception	0x5	0x1
Blank	0x6	0x4
Reflexes	0xA	0x1
Blank	0xB	0x4
Spell Loadout	0xE	0x18

Some levels have wizards defined beyond the default stats even though they are not present in the level, suggesting they may have been cut (e.g. the first level has a very low level Vodor defined despite it not featuring any enemy wizards).

Misc Level Setup

This is always found after the wizard definitions at 9790. These define the target amount of mana for the player to collect on the level, the number of wizards in the level, and starting castle levels of each wizard (from 0 to 7).

Attribute	Offset (hex)	Length (hex)	Notes
Mana Target (%)	0x0	0x1	The percentage of the total mana defined in the first four bytes of the file needed to beat the level
Blank	0x1	0x1
Number of Wizards in level	0x2	0x1	Only the player is 1. Therefore 2 would be the player and one enemy wizard (Vodor). Max is 8
Blank	0x3	0x1
Player Castle Level	0x4	0x1	Always set to 0
Vodor Castle Level	0x5	0x1	Determines what level this wizard's castle starts at, and therefore their mana state
Gryshnak Castle Level	0x6	0x1	Determines what level this wizard's castle starts at, and therefore their mana state
Mahmoud Castle Level	0x7	0x1	Determines what level this wizard's castle starts at, and therefore their mana state
Syed Castle Level	0x8	0x1	Determines what level this wizard's castle starts at, and therefore their mana state
Raschid Castle Level	0x9	0x1	Determines what level this wizard's castle starts at, and therefore their mana state
Alhabbal Castle Level	0xA	0x1	Determines what level this wizard's castle starts at, and therefore their mana state
Scheherazade Castle Level	0xB	0x1	Determines what level this wizard's castle starts at, and therefore their mana state

Spell Loadouts

Keep in mind that the final game only respects spell loadouts on certain levels. Early on the game ignores what is set in the level to use the inventory the player has built up so far in the game. If a different level is played in one of these slots (most obviously level one), the player will start with no spells at all.