Alien Trilogy MAP
Contents
MAP
- Format Type : File container/MAP File
- Extensions: .MAP
- Platforms: PC/PS1/Sega Saturn
- Endian Order : Little Endian/Big Endian
MAP Format specifics
This article will be quite extensive, since the format of the map is large enough.
The format is in many ways similar to BND, it also has "sections" with "names" in its set, with its own peculiarities.
The file with the map is also accompanied by a file with a texture and a texture mesh (for 3D geometry).
The following sections are found in this file:
MAP0 - a section with a description of the map itself (geometry, logic, collision)
D000 (0,1,2 ....) - Dynamic objects on the map, such as doors \ elevators \ other objects
Despite the fact that the file has few sections, however, the section with information about the map itself has many "blocks" that are not marked with anything and information about them is only in the header of the section itself. This article will describe all the blocks that have been found empirically, as well as their structure and formulas by which they are calculated.
MAP Format Description
Current format description at the moment. Description of each block below.
// Alien Trilogy
// MAP File format
Size Comment
--------------------------------------------------
0x04 46 4F 52 4D FORM
0x04 - file data size in bytes, BIG-ENDIAN
0x04 - the number of maps in the file with text.(zero, text)
- then there is information about the geometry of the map and its content, namely:
Size Comment
--------------------------------------------------
0x04 - Map name, text
0x04 - Map data size, BIG-ENDIAN
0x02 - Number of vertices? LITTLE-ENDIAN
Formula - multiply the value of these two bytes by 8
(6 bytes for 3 points + 2 bytes zeros)
0x02 - Number of quads (rectangles) .LITTLE-ENDIAN
Formula - the value of these 2 bytes multiply by 20
(16 bytes dot indices and 4 bytes info)
0x02 - The length of the "rectangle" of the mini-map
(physics engine)(Little-Endian)
0x02 - The width of the "rectangle" of the mini-map
(physics engine)(Little-Endian)
Formula for these bytes = multiply length by width and
multiply the resulting value by 16
(16 bytes describe one cell.)
0x02 - The starting position of the player along the X-axis
0x02 - Player's starting position along the Y axis
A small correction about the X and Y positions.
When walking, the "X / Y numbers" of the square
are written in the positions
collisions, not fixed coordinates like vertices.
0x02 - Unknown bytes.
0x02 - Field describing monsters that simply spawn.
Formula = number of elements multiplied by 20
(20 bytes per monster)
0x02 - Pickup description field
Formula = number of elements multiplied by 8
(8 bytes per pickup)
0x02 - Description field for "boxes" and
similar objects (switches, barrels)
Formula = number of elements multiplied by 16
(16 bytes per box)
0x02 - Number of all doors on the map.
Formula = value multiplied by 8
(8 bytes one element)
0x02 - Unknown bytes.
0x02 - Player's Start Angle
0x06 - Unknown bytes
0x04 - Unknown value, somehow affects
on monsters at the level. If there are monsters on the level
and set zeros, then rendering is disabled for monsters
sprites, but they themselves do not disappear
One vertex format
Size Comment -------------------------------------------------- 0x02 - X coordinate (signed, LITTLE-ENDIAN, short) 0x02 - Y coordinate 0x02 - Z coordinate 0x02 - unknown value, it seems to be always 0
One quad format
Size Comment
--------------------------------------------------
0x04 - First point. LITTLE-ENDIAN
0x04 - Second point
0x04 - Third point
0x04 - Is the fourth point. maybe -1 (0xFFFFFFFF),
then this is a triangle and you
need to duplicate the third point.
0x02 - Index of the quad texture
0x02 - Is a certain parameter. Apparently something on the display.
Format of one square of collision
The game does not interact with the three-dimensional map and the 3D model is just a decoration. All moving objects are described in the section D000, which is responsible for dynamic objects. From the experience with the heights of the blocks, at first glance, it turned out that a floor-ceiling system was used, as in a doom / duke. The logic of the engine becomes clear. Apparently the game is actually technically divided into a "grid of blocks" and takes the position of the block (length-line) as coordinates of objects. The rest is "considered" already further. Such a system also has its drawbacks, namely, doors and switches can be opened with the "back", because the engine in fact looks at the push of a button in the block itself.
Size Comment
--------------------------------------------------
0x04 - Block Number?
0x02 - Unknown bytes.
0x02 - Unknown bytes.
0x01 - It seems the height of the block
ceiling rendering (black fog)
0x01 - It seems the height of the block
floor rendering (black fog) (not exactly)
0x01 - Block ceiling height
0x01 - Block floor height
0x02 - Unknown bytes.
0x01 - The color of the lighting in the block?
I found the following values:
255 - colors red
64 - blinking red
128 - blue
160 - yellow
192 - gray?
224 - orange roofing felts,
red roofing felts.
from 1 to 10 - bright light in the block
11 to 17 - is it dark in the block?
18 - bright red blinks
20 - full light in the block
22 - orange blinks
24 - blinks dark orange
30 - blinks from dark to white
0x01 - Actions?(Open door, use switches and other...)
value:
1 - starting door
3 - a door that opens with a switch
9 - end of level
One monster format
Size Comment
--------------------------------------------------
0x01 - Type of attack? (Maybe the type of monster)
0x01 - X coordinate? Like Plyer start position.
0x01 - Y coordinate? Like Plyer start position.
0x01 - Z coordinate? (Apparently FF means to spawn on the floor)
0x02 - Number of health points (apparently in a fixed number)
0x01 - What object will spawn upon death (index)
0x01 - Incomprehensible byte, if it is greater than zero,
then the monster will not spawn
0?04 - Incomprehensible bytes, the effect of the change is not clear.
0x02 - Incomprehensible bytes, changes are not noticeable
(the angle of rotation when spawning is possible)
0x02 - The speed of movement of the object (monster).
0?04 - Incomprehensible bytes, the effect is not clear when changed.
The same monster can have different meanings
One pickup format
Size Comment
--------------------------------------------------
0x01 - X coordinate? Like Plyer start position
0x01 - Y coordinate? Like Plyer start position
0x01 - Pickup type, index
Types:
0 - pistol
1 - shotgun
2 - pulsator
3 - flamethrower
4 - smart gun
5 - not used
6 - seismic charge
7 - battery (for switches using the
"battery" type)
8 - night vision goggles
9 - pistol clip
10 - shotgun cartridges
11 - pulsator holder
12 - underbarrel grenade for a grenade launcher
13 - fuel for a flamethrower
14 - clip for smart gun
15 - identification card (which flies
out of the colonists / guards)
16 - auto map
17 - hyper pack
18 - armor (acid west), apparently protects against acid
19 - simple armor
20 - first aid kit
21 - bandage (+1 health)
22 - safety boots
23 - adrenaline
24 - bandage?
25 - soldier's lamp
The types above can be lifted, the following are not
lifted (apparently used for debugging)
26 - a case from a shotgun
27 - a sleeve from a pistol
Values ??above 27 (28 and beyond)
consistently result in flyouts.
0x01 - The number that the pickup gives out when lifting
0x01 - Some kind of multiplier for the previous value
0x01 - An incomprehensible value, like zero everywhere
0x01 - Apparently Z coordinate
0x01 - Also some kind of quantity for a pickup, it is not clear how it works.
One box format
The format of "boxes" (apparently 16 bytes), one nuance, in the field of boxes, not only boxes are described. Special objects such as barrels or switch models can also be described in this field.
Size Comment
--------------------------------------------------
0x01 - X coordinate?
0x01 - Y coordinate?
0x01 - Type of "box" (Apparently and type and model at the same time)
Types:
19 - a box that cannot be blown up
20 is a regular box that can be blown up
21 - empty object (at the moment),
maybe a switch for levels on the ship
22 - another small switch,
the difference is at the bottom of the model (lightning is drawn)
23 - barrel explodes.
24 - switch with animation (small switch)
25 - "double box" (two boxes on top of each other that can be blown up)
26 - wide switch with zipper
27 - wide switch without zipper
28 - an empty object that can be shot
29 - an empty object that can be shot through, something will spawn on death
30 - is a regular box that can be blown up
0x01 - What the object will spawn upon death 00 - apparently a pickup,
02 - apparently a monster
0x02 - Until I realized what these two bytes do
0x01 - Apparently the index of the object that needs to be spawned
0x01 - Apparently the index of the second object that needs to be spawned
0x08 - Incompletely understandable values, the last two bytes somehow influence
the speed at which spawned objects fly out
One door format
Size Comment -------------------------------------------------- 0x01 - X coordinate 0x01 - Y coordinate 0x01 - Incomprehensible byte 0?01 - Door open time 0x01 - Door tag (for use in collage blocks) 0x01 - Incomprehensible byte 0x01 - Angle of rotation of the door model relative to the map 0x01 - Model index from section D000 \ 1 \ 2 \ 3 ...
