3D model format

From Trickstart wiki
Revision as of 18:13, 3 May 2021 by Halamix2 (talk | contribs)

Stores 3D models, more investigation needed.

If "signed" was not added assume unsigned value

Current analysis: https://docs.google.com/spreadsheets/d/1Hk_EIYk2E6hVd747JJmC9pqqqh_dVafM3dqOkeRp3No/edit?usp=sharing

Thanks to Martin for initial format reversing.

  • Magic - PMD V1.83
    • some files use version 1.82 instead, but they aren't used by the game, the engine in PC version won't recognise anything other than 1.83
    • There is one unused mention of PMD V1.71 in the game binary
Offset Size Description
0x0 0x18? Magic - PMD V1.83
0x18 0x4 Type - 0 = shadow & skybox; 1 = track; 2 = car
0x1C 0x4 Zeroes?
0x20 0x94? offsetsTable
0xB4 0x94? offsetsTable sizes

Offsets table

You have to add 0x148 to each value to get proper pointers

Bold IDs are in all files, rest of them are specific for tracks

Some of these are either unused or possibly repurposed

All blocks seems to be 32-bit aligned.

If the offset/size address is empty it's always set to zero.

ID offset size offset Description
0 0x20 0xb4 Martin think it might be some sort of colider
1 0x24 0xb8 polygons data?
2 0x28 0xbc UV texture data?
3 0x2c 0xc0 vertex data?
4 0x30 0xc4 faces data?
5 0x34 0xc8 Textures names
6 0x38 0xcc Offsets to texture names, absolute addresses in file, add 0x148
7 0x3c 0xd0 Each element is 16B long, ?, ?, float, float
8 0x40 0xd4 Holds IDs of elements in 7
9 0x44 0xd8 surface transforms data?
10 0x48 0xdc meshes data
11 0x4c 0xe0 LOD metadata, maybe something more
12 0xe4 for non-tracks it's size of 1 divided by 16, unknown for tracks
14 0x58 offset marks end of file
15 0x5c 0xf0
16 0x60 0xf4
17 0x64 0xf8
18 0xfc stores size of 20 divided by 0x90
19 0x100
20 0x70 0x104
21 0x74 0x108 List of points, looks like AI curve
22 0x78 0x10c
23 0x7c 0x110
24 0x80 0x114
25 0x84 0x118
26 0x88 0x11c
27 0x8c 0x120
28 0x90 0x124
29 0x94 0x128
30 0x98 0x12c
31 0x9c 0x130
32 0xa0 0x134

Basic elements

Each model contains these elements

LOD metadata

I'm skipping most of this block, as it's unused or used directly by the engine to store some of the calculated addresses

If the number of LODs is set to less than 3, later ones just copy id from previous ones

Offset Type Description
0x0 short Same as file type at 0x18
0x2 short Unknown, always set to 1 for normal files, 2 for tracks and 4 for cars
0x1C float Always 1.0
0x20 byte unknown
0x21 byte unknown
0x22 short unknown
0x24 int number of meshes (surfaces) for each LOD
0x48 int ID of first mesh for LOD 0
0x4c int ID of first mesh for LOD 1
0x50 int ID of first mesh for LOD 2
0x54 int ID of first mesh for LOD 3
0x58 int Number of additional LODs, can be 0-3


Offset Type Description
0x0 float X
0x4 float Y
0x8 float Z
0xC float unknown, might be weight


Offset Type Description
0x0 byte vertex count
0x1 byte material ID
0x2 byte unknown
0x3 byte unknown, might be weight
0x4 short vertices index?
0x6 short face table start index

UV mapping

Offset Type Description
0x0 float X
0x4 float Y
0x8 short vertex index
0xA short unknown, might be texture index
0xC int normal vector?


Offset Type Description
0x0 short index ?


Offset Type Description
0x0 float[4][4] some kind of matrix
0x40 int[4] ? unknown four ints?


Offset Type Description
0x0 short[4] unknown
0x8 short transform index?
0xA short[3] zeros?
0x10 int[3] zeros?
0x1C float weight?
0x20 short unknown (index?)
0x22 short unknown (index?)
0x24 short polys count
0x26 short UVs count
0x28 int vertices count
0x2C int UVs start index
0x30 int vertices start index
0x34 int polys start index
0x38 int[2] zeros?

Track data

Block 15

Offset Type Description
0x0 signed int If there is any data it's set to 1, last one is always set to -1
0xC float unknown
0x10 float unknown

Block 16

12 floats and 4 ints, seems similar to 3 points (each 4th float is always 1.0)

Block 17

0x28 bytes, seems like there are 4 floats (perhaps intensity/R/G/B values?), rest unused?

Block 20

Long, each element 0x90 bytes long

Block 21 / 22

Block 21 holds list of vertices, possibly defining track for AI.

There are 5 curves in this block, 255 points each.

Curve 0, 2-4 are track curves, curve 1 is for the charging station.

Chall1 only has one curve.

Block 22

Holds the same number of elements as is the number of curves.

Each element is 0x1C long

WIP, so far hardcoded data from one track

Offset Type Description
0x0 int id
0x4 int starting vertex offset
0x8 int length?
0xC int 0x1
0x10 int 0x2
0x14 int 0xa
0x18 float?

Block 23

List of vertices

Block 24

list of faces? Each element 0x2 bytes long

Block 25

list of faces? Each element 0x2 bytes long

Block 26

Each element 0x40 long.

Block 27

list of faces? Each element 0x2 bytes long

Block 28

list of faces? Each element 0x2 bytes long

Block 29

Each element 0x4 long.

Block 30

Each element 0x8 long.

Block 31

Each element 0x30 long.

4 floats (last one set to 1.0), and 16 shorts.

Block 32

0x38 bytes, mostly zeros

Offset Type Description
0x18 float Always 50.0
0x20 float Always 100.0
0x24 int