Video tutorials on model formats reversing

[daemon1]

TLoU part 2. Includes TLoU vs Uncharted 2 part, EDGE decompression and weights. After all, EDGE proved to be different in different games, though, nothing impossible.

https://youtu.be/VBqYEaqCzxY

[JohnHudeski]

It ended?

[daemon1]

what exactly is ended?

[mono24]

I think he's trying to find out if you ended the tutorials, or there will be more in the future in various ways/games and such.

[zaykho]

Hum interesting, I can already read and make tools to export mesh, the only thing I'm unable to do is : read/export Bones/Skeleton animation and sometimes textures/palettes, so I think it's time for me to watch those tutorials. ; )

Thank you again daemon1 for your contributions.

[JohnHudeski]

Is it possible to do a tutorial on how to find encryption keys
or how to find out how exe read un-common structures

[daemon1]

Is it possible to do a tutorial on how to find encryption keys
or how to find out how exe read un-common structures

find encryption keys - not very good idea. Such things are better kept private.
As for "how exe read" - this is rather generic, so no need to do special video about game formats, there are many existing tutorials in reverse engeneering area to cover this.

[JohnHudeski]

But if the archive file containing the model asset or the ai lua is in an encrypted file.
For example, there was a game that encrypted all the game settings xml in blowfish
It really sucked cos the game had broken AI

[daemon1]

People asked me to make a video of real reversing process, from start to finish, thinking, making mistakes and so on.
I take an example from Twisted Metal (2012) game on PS3.

https://youtu.be/YXVuRl1QPrg
https://youtu.be/b9-kkkL8Q2s

[JakeMiles]

Thanks for you! For sharing tutorials and tips

[daemon1]

2 more tutorials using same twised metal game as an example, so you can better understand how the above work was done:

Basic things about 3d data reversing: how 3D data looks like in hex: compression, encryption, common data types (ints/floats), main data structures (geometry/bones/textures)
https://www.youtube.com/watch?v=i_uWw-UDpEo

Finding geometry buffers and their properties
https://www.youtube.com/watch?v=swdOXDVkGUU

[EPYCSPYDER]

Thanks for making the tutorials, I followed Twisted Metal PS3 reversing and wrote your code got the car .obj from ui.ngp
How can I make it work with little endian.

HJA_test

Code: Select all

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Globalization;

namespace HJA_test
{
    class BinaryReaderBE : BinaryReader
    {
        private byte[] a16 = new byte[2];
        private byte[] a32 = new byte[4];
        private byte[] a64 = new byte[8];
        public BinaryReaderBE(System.IO.Stream stream) : base(stream) { }
        public override float ReadSingle()
        {
            a32 = base.ReadBytes(4);
            Array.Reverse(a32);
            return BitConverter.ToSingle(a32, 0);
        }
        public override UInt16 ReadUInt16()
        {
            a16 = base.ReadBytes(2);
            Array.Reverse(a16);
            return BitConverter.ToUInt16(a16, 0);
        }
        public override Int16 ReadInt16()
        {
            a16 = base.ReadBytes(2);
            Array.Reverse(a16);
            return BitConverter.ToInt16(a16, 0);
        }
        public override Int32 ReadInt32()
        {
            a32 = base.ReadBytes(4);
            Array.Reverse(a32);
            return BitConverter.ToInt16(a32, 0);
        }
        public override UInt32 ReadUInt32()
        {
            a32 = base.ReadBytes(4);
            Array.Reverse(a32);
            return BitConverter.ToUInt32(a32, 0);
        }
        public override long ReadInt64()
        {
            a64 = base.ReadBytes(8);
            Array.Reverse(a64);
            return BitConverter.ToInt64(a64, 0);
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            NumberFormatInfo nfi = new NumberFormatInfo();
            nfi.NumberDecimalSeparator = ".";

            float x = 0;

            var sw = new StreamWriter(Path.GetFileNameWithoutExtension(args[0]) + ".obj");
            sw.Write(x.ToString("0.######", nfi));
        }
    }
}

TM2012

Code: Select all

using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;
using System.Text;
using System.Globalization;

namespace TM2012
{
    class BinaryReaderBE : BinaryReader
    {
        private byte[] a16 = new byte[2];
        private byte[] a32 = new byte[4];
        private byte[] a64 = new byte[8];
        public BinaryReaderBE(System.IO.Stream stream) : base(stream) { }
        public override float ReadSingle()
        {
            a32 = base.ReadBytes(4);
            Array.Reverse(a32);
            return BitConverter.ToSingle(a32, 0);
        }
        public override UInt16 ReadUInt16()
        {
            a16 = base.ReadBytes(2);
            Array.Reverse(a16);
            return BitConverter.ToUInt16(a16, 0);
        }
        public override Int16 ReadInt16()
        {
            a16 = base.ReadBytes(2);
            Array.Reverse(a16);
            return BitConverter.ToInt16(a16, 0);
        }
        public override Int32 ReadInt32()
        {
            a32 = base.ReadBytes(4);
            Array.Reverse(a32);
            return BitConverter.ToInt16(a32, 0);
        }
        public override UInt32 ReadUInt32()
        {
            a32 = base.ReadBytes(4);
            Array.Reverse(a32);
            return BitConverter.ToUInt32(a32, 0);
        }
        public override long ReadInt64()
        {
            a64 = base.ReadBytes(8);
            Array.Reverse(a64);
            return BitConverter.ToInt64(a64, 0);
        }
    }
    class tm2012
    {
        static void Main(string[] args)
        {
            NumberFormatInfo nfi = new NumberFormatInfo();
            nfi.NumberDecimalSeparator = ".";

            int i;
            float x, y, z;

            var fs = new FileStream("C:\\ui.ngp", FileMode.Open, FileAccess.Read);
            var br = new BinaryReaderBE(fs);
            var sw = new StreamWriter("ui.obj");

            fs.Seek(0x29ef30, SeekOrigin.Begin);
            int nv = 0x12f8;
            for (i = 0; i < nv; i++)
            {
                x = br.ReadInt16() / 4096f;
                y = br.ReadInt16() / 4096f;
                z = br.ReadInt16() / 4096f;
                sw.Write("v " + x.ToString("0.######", nfi));
                sw.Write("  " + y.ToString("0.######", nfi));
                sw.Write("  " + z.ToString("0.######", nfi));
                sw.WriteLine();
            }

            fs.Seek(0x298500, SeekOrigin.Begin);
            int nf = 0x3513 / 3;
            int f1, f2, f3;
            for (i = 0; i < nf; i++)
            {
                f1 = br.ReadUInt16() + 1; f2 = br.ReadUInt16() + 1; f3 = br.ReadUInt16() + 1;
                sw.WriteLine("f " + f1 + " " + f2 + " " + f3);
            }

            sw.Close();
        }
    }
}

[daemon1]

Change this:

Code: Select all

var br = new BinaryReaderBE(fs);

to this:

Code: Select all

var br = new BinaryReader(fs);

It will use the "usual" BinaryReader, which is little endian.

[EPYCSPYDER]

Any chance you would do a code tutorial on the smd mesh/skeleton blender tools you used with The Last of Us?

[mariokart64n]

daemon's videos are very well organized, so alot of respect to him for making these videos because they are so clear and informative.

I would like to also share some information and videos, for those who may be interested.. If this is not okay to share here then please let me know and I will remove it.


My Own Videos:

1. 14:17 -> What is Binary
2. 12:20 -> Hex Editing
3. 21:41 -> Programming
4. 14:36 -> Programming with Data Types
5. 12:07 -> Hex Editor
6. 09:43 -> Model Theory
7. 24:58 -> Format Study
8. 18:23 -> Writing C++ Byte Class
9. 12:20 -> Writing C++ Mesh Reader / Exporter
10. 34:51 -> Writing Maxscript Mesh Importer
11. 34:12 -> Writing Noesis Python Mesh Importer

Simple Code Examples

Blender

Code: Select all

import bpy
import struct
from pathlib import Path

SEEK_ABS = 0
SEEK_REL = 1
SEEK_END = 2

class fopen:
    little_endian = True
    file = ""
    data = bytes()
    size = 0
    pos = 0
    isGood = False
    def __init__(self, filename = None, mode='rb', isLittleEndian=True):
        if filename != None and Path(filename).is_file():
            self.data = open(filename, mode).read()
            self.size = len(self.data)
            self.pos = 0
            self.file = filename
            self.little_endian = isLittleEndian
            self.isGood = True
        return None

    def read_and_unpack(self, unpack, size):
        '''
          Charactor, Byte-order
          @,         native, native
          =,         native, standard
          <,         little endian
          >,         big endian
          !,         network

          Format, C-type,         Python-type, Size[byte]
          c,      char,           byte,        1
          b,      signed char,    integer,     1
          B,      unsigned char,  integer,     1
          h,      short,          integer,     2
          H,      unsigned short, integer,     2
          i,      int,            integer,     4
          I,      unsigned int,   integer,     4
          f,      float,          float,       4
          d,      double,         float,       8
        '''
        value = 0
        if self.size > 0 and self.pos + size < self.size:
            value = struct.unpack_from(unpack, self.data, self.pos)[0]
            self.pos += size
        return value

    def set_pointer(self, offset):
        self.pos = offset
        return None

def fseek(bitStream, offset, dir):
    if dir == 0:
        bitStream.set_pointer(offset)
    elif dir == 1:
        bitStream.set_pointer(bitStream.pos + offset)
    elif dir == 2:
        bitStream.set_pointer(bitStream.pos - offset)
    return None

def readShort(bitStream, isSigned=0):
    fmt = '>' if not bitStream.little_endian else '<'
    fmt += 'h' if isSigned == 0 else 'H'
    return (bitStream.read_and_unpack(fmt, 2))

def readLong(bitStream, isSigned=0):
    fmt = '>' if not bitStream.little_endian else '<'
    fmt += 'i' if isSigned == 0 else 'I'
    return (bitStream.read_and_unpack(fmt, 4))

def readFloat(bitStream):
    fmt = '>f' if not bitStream.little_endian else '<f'
    return (bitStream.read_and_unpack(fmt, 4))

def mesh (vertices = [], faces = []):
    bpy.context.view_layer.objects.active = None
    msh = bpy.data.meshes.new('Mesh')
    msh.from_pydata(vertArray, [], faceArray)
    msh.update()
    obj = bpy.data.objects.new('Object', msh)
    bpy.data.collections[bpy.context.view_layer.active_layer_collection.name].objects.link(obj)



f = fopen('C:\\Users\\Corey\\Desktop\\grimlock\\models\\vis1\\geo_veh_c_sec_wheel.xgm', 'rb')

fseek(f, 0x1D8, SEEK_ABS)

# Reading Buffer Info
vertex_buffer_size = readLong(f)
index_buffer_size =  readLong(f)

# Calculate the Counts from Buffer Info
vertex_buffer_stride = 24
index_buffer_stride = 2
vertex_count = int(vertex_buffer_size / vertex_buffer_stride)
index_count = int(index_buffer_size / index_buffer_stride / 3)

# Read The buffers
vertArray = []
faceArray = []
fseek(f, 0x29C, SEEK_ABS)

for i in range(0, vertex_count):
    vertArray.append( (readFloat(f),  readFloat(f), readFloat(f)) )
    fseek(f, (vertex_buffer_stride - 12), SEEK_REL)
    
for i in range(0,index_count):
    faceArray.append((readShort(f),  readShort (f), readShort (f)))
    

# make mesh
mesh(vertArray, faceArray)

3ds Max (MaxScript)

Code: Select all

f = fopen "C:\\Users\\Corey\\Desktop\\grimlock\\models\\vis1\\geo_veh_c_sec_wheel.xgm" "rb"

SEEK_ABS = #seek_set
SEEK_REL = #seek_cur
SEEK_END = #seek_end

fseek f 0x1D8 SEEK_ABS

-- Reading Buffer Info
vertex_buffer_size = readLong f
index_buffer_size =  readLong f

-- Calculate the Counts from Buffer Info
vertex_buffer_stride = 24
index_buffer_stride = 2
vertex_count = vertex_buffer_size / vertex_buffer_stride
index_count = index_buffer_size / index_buffer_stride / 3

-- Read The buffers
vertArray = #()
faceArray = #()
fseek f 0x29C SEEK_ABS

for i = 1 to vertex_count do (
	append vertArray [-readFloat f,  readFloat f, readFloat f]
	fseek f (vertex_buffer_stride - 12) SEEK_REL
	)

for i = 1 to index_count do (
	append faceArray ([readShort f,  readShort f, readShort f] + 1)
	)

-- import to the scene
mesh vertices:vertArray faces:faceArray

fclose f

Cinema4D

Code: Select all

import c4d
import maxon
from c4d import *
from maxon import *

# Enums!
SEEK_ABS = 0
SEEK_REL = 1
SEEK_END = 2

class fopen: # reads file to buffer, and reads values from buffer
    byteStream = maxon.BaseArray(maxon.Char)
    size = 0
    pos = 0
    eof = False # End of Stream
    bebo = False # Big Endian Byte Order
    def __init__(self, filename = ""):
        if filename != "":
            fname = maxon.Url(filename)
            if (fname.IoDetect() ==  maxon.IODETECT.FILE):
                inputStream = fname.OpenInputStream()
                self.size = inputStream.GetStreamLength()
                if self.size > 0:
                    self.byteStream.Resize(self.size)
                    inputStream.ReadEOS(self.byteStream)
                    self.pos = 0
                inputStream.Close()
    def seek (self, offset, curdir = 0):
        if curdir == SEEK_ABS:
            self.pos = offset
        elif curdir == SEEK_REL:
            self.pos += offset
        elif curdir == SEEK_END:
            self.pos = self.size - offset
        if self.pos > self.size or self.pos < 0:
            self.pos = 0
            self.eof = True
        return not self.eof
    def tell (self):
        return self.pos
    def unsigned_to_signed (self, n, nbits):
        result = n
        if (n > pow(2, nbits) / 2):
            result = n - pow(2, nbits)
        return result
    def readByte (self, isSigned = True):
        val = -1
        if self.pos + 1 < self.size:
            val = ord(self.byteStream[self.pos])
            self.pos+=1
            if isSigned: val = self.unsigned_to_signed(val, 8)
        return val
    def readShort (self, isSigned = True):
        byteOrder = [0, 1]
        if self.bebo: byteOrder = [1, 0]
        val = -1
        if self.pos + 1 < self.size:
            val =  ord(self.byteStream[self.pos + byteOrder[0]]) * 0x0001
            val += ord(self.byteStream[self.pos + byteOrder[1]]) * 0x0100
            self.pos+=2
            if isSigned: val = self.unsigned_to_signed(val, 16)
        return val
    def readLong (self, isSigned = True):
        byteOrder = [0, 1, 2, 3]
        if self.bebo: byteOrder = [3, 2, 1, 0]
        val = -1
        if self.pos + 1 < self.size:
            val =  ord(self.byteStream[self.pos + byteOrder[0]]) * 0x00000001
            val += ord(self.byteStream[self.pos + byteOrder[1]]) * 0x00000100
            val += ord(self.byteStream[self.pos + byteOrder[2]]) * 0x00010000
            val += ord(self.byteStream[self.pos + byteOrder[3]]) * 0x01000000
            self.pos+=4
            if isSigned: val = self.unsigned_to_signed(val, 32)
        return val
    def readFloat (self):
        inputAsInt = self.readLong(False)
        fraction = 0.0
        for i in range(0, 23): fraction += (1 & (inputAsInt >> ((23 - i) - 1))) * (pow(2, -(i + 1)))
        sign = -1
        if (inputAsInt >> 31) & 0x00000001 == 0:
            sign = 1
        return (sign * (1 + fraction) * (pow(2, (((inputAsInt & 0x7F800000) >> 23) - 127))))

class mesh: # builds mesh into C4D
    def __init__(self, vertices = [], faces = []):
        if len(vertices) > 0 and len(faces) > 0:
            mypoly = c4d.BaseObject(c4d.Opolygon) #Create an empty polygon object
            mypoly.ResizeObject(len(vertices), len(faces)) #New number of points, New number of polygons
            for i in range(0, len(vertices)):
                mypoly.SetPoint(i, vertices[i])
            for i in range(0, len(faces)):
               mypoly.SetPolygon(i, faces[i])
            doc.InsertObject(mypoly,None,None)
            mypoly.Message(c4d.MSG_UPDATE)
            c4d.EventAdd()


f = fopen("C:\\Users\\Corey\\Desktop\\grimlock\\models\\vis1\\geo_veh_c_sec_wheel.xgm")

f.seek(0x1D8, SEEK_ABS)

# Reading Buffer Info
vertex_buffer_size = f.readLong()
index_buffer_size =  f.readLong()

# Calculate the Counts from Buffer Info
vertex_buffer_stride = 24
index_buffer_stride = 2
vertex_count = int(vertex_buffer_size / vertex_buffer_stride)
index_count = int(index_buffer_size / index_buffer_stride / 3)

# Read The buffers
vertArray = []
faceArray = []
f.seek(0x29C, SEEK_ABS)

for i in range(0, vertex_count):
    vertArray.append(c4d.Vector(f.readFloat(), f.readFloat(), f.readFloat()))
    f.seek(vertex_buffer_stride - 12, SEEK_REL)
    
for i in range(0,index_count):
    faceArray.append(c4d.CPolygon(f.readShort(), f.readShort(), f.readShort()))


# make mesh
mesh(vertArray, faceArray)

Noesis

Code: Select all

from inc_noesis import *


def registerNoesisTypes():
    handle = noesis.register("load an xgm", ".xgm")
    noesis.setHandlerTypeCheck(handle, noepyCheckType)
    noesis.setHandlerLoadModel(handle, noepyLoadModel)
    noesis.logPopup()
    return 1


def noepyCheckType(data):
    if len(data) < 12: return 0
    f = NoeBitStream(data)
    f.seek(8)
    if f.readInt() != 0x4D534758: return 0
    return 1


def noepyLoadModel(data, mdlList):
    if len(data) < 12: return 0
    f = NoeBitStream(data)
    f.seek(8)
    if f.readInt() != 0x4D534758: return 0

    f.seek(0x1D8, NOESEEK_ABS)

    # Reading Buffer Info
    vertex_buffer_size = f.readInt()
    index_buffer_size = f.readInt()

    # Calculate the Counts from Buffer Info
    vertex_buffer_stride = 24
    index_buffer_stride = 2
    vertex_count = int(vertex_buffer_size / vertex_buffer_stride)
    index_count = int(index_buffer_size / index_buffer_stride / 3)

    # Read The buffers
    vertArray = []
    faceArray = []
    f.seek(0x29C, NOESEEK_ABS)

    for i in range(0, vertex_count):
        vertArray.append(NoeVec3((f.readFloat(), f.readFloat(), f.readFloat())))
        f.seek((vertex_buffer_stride - 12), NOESEEK_REL)

    for i in range(0, index_count):
        f1 = f.readShort()
        f2 = f.readShort()
        f3 = f.readShort()
        faceArray.append(f1)
        faceArray.append(f3)
        faceArray.append(f2)

    # import to the scene
    mdl = NoeModel()
    mdl.setMeshes([NoeMesh(faceArray, vertArray)])
    mdlList.append(mdl)

    return 1

QuickBMS

Code: Select all

# script for QuickBMS http://quickbms.aluigi.org


# Set File Number
f = 0

goto 0x1D8 f SEEK_SET

# Reading Buffer Info
get vertex_buffer_size long f
get index_buffer_size long f

# Calculate the Counts from Buffer Info
set vertex_buffer_stride long 24
set index_buffer_stride long 2

set vertex_count long vertex_buffer_size
set index_count long index_buffer_size
math vertex_count /= vertex_buffer_stride
math index_count /= index_buffer_stride
math index_count /= 3

# Set ObjFile
set obj string "o mesh"
set temp string ""
string temp p= "%c%c%c%c" 0x0D 0x0A 0x0D 0x0A
string obj += temp

# Read The buffers
set skip long 0
math skip = vertex_buffer_stride
math skip -= 12

goto 0x29C f SEEK_SET
for i = 0 < vertex_count
    
    get pos_x long f
    get pos_y long f
    get pos_z long f
    
    string temp p= "v %f" pos_x
    string obj += temp
    
    string temp p= " %f" pos_y
    string obj += temp
    
    string temp p= " %f" pos_z
    string obj += temp
    
    string temp p= "%c%c" 0x0D 0x0A
    string obj += temp

    goto skip f SEEK_CUR
next i

string temp p= "%c%c%c%c" 0x0D 0x0A 0x0D 0x0A
string obj += temp
for i = 0 < index_count
    get face_a short f
    get face_b short f
    get face_c short f
    
    math face_a += 1
    math face_b += 1
    math face_c += 1
    
    string temp p= "f %i" face_a
    string obj += temp
    
    string temp p= " %i" face_c
    string obj += temp
    
    string temp p= " %i" face_b
    string obj += temp
    
    string temp p= "%c%c" 0x0D 0x0A
    string obj += temp
    
next i

// write the OBJ
strlen obj_size obj
putvarchr MEMORY_FILE obj_size 0
put obj string MEMORY_FILE
get NAME basename
string file_name p= "%s.obj" NAME
log file_name 0 obj_size MEMORY_FILE

C++

Code: Select all

#include <iostream>
#include <fstream>
#include <iomanip>

using namespace std;

#define SEEK_ABS 0
#define SEEK_REL 1
#define SEEK_END 2

struct bytes {
	ifstream file;
	bool isGood;
	bytes (string filename) {
		file.open (filename.c_str(), std::ifstream::binary);
		isGood = file.good();
		}
	~bytes () {
		file.close();
		}
	int16_t readInt16 () {
		int32_t input;
		file.read(reinterpret_cast<char*>(&input), sizeof(int16_t));
		return input;
		}
	int32_t readInt32 () {
		int32_t input;
		file.read(reinterpret_cast<char*>(&input), sizeof(int32_t));
		return input;
		}
	float readFloat32 () {
		float input;
		file.read(reinterpret_cast<char*>(&input), sizeof(input));
		return input;
		}
	void seek (int offset, int dir = 0) {
		if (dir == SEEK_ABS) {
			file.seekg(offset, file.beg);
			}
		else if (dir == SEEK_REL) {
			file.seekg(offset, file.cur);
			}
		else if (dir == SEEK_END) {
			file.seekg(offset, file.end);
			}
		}
	};

int main() {

	// Open File
	bytes f("C:\\Users\\Corey\\Desktop\\grimlock\\models\\vis1\\geo_veh_c_sec_wheel.xgm");


	// Check is open
	if (!f.isGood) {return 0;}

	// Read the Buffer Info
	f.seek(0x1D8);
	int vertex_buffer_size = f.readInt32();
	int index_buffer_size = f.readInt32();

	// Calculate the Counts from Buffer Info
	int vertex_buffer_stride = 24;
	int index_buffer_stride = 2;
	int vertex_count = vertex_buffer_size / vertex_buffer_stride;
	int index_count = index_buffer_size / index_buffer_stride / 3;


	cout << "vertex_buffer_size: " << vertex_buffer_size << endl;
	cout << "index_buffer_size: " << index_buffer_size << endl;

	// Read Buffer
	f.seek(0x29C);

	// write the OBJ
	std::ofstream out;
	out.open ("C:\\Users\\Corey\\Desktop\\grimlock\\models\\vis1\\geo_veh_c_sec_wheel.obj", std::ofstream::out);

	out << "o meshobject" << endl << endl;

	for (int i = 0; i < vertex_count; i++) {
		out  << std::setprecision(6) << "v " << f.readFloat32();
		out  << std::setprecision(6) << " " << f.readFloat32();
		out  << std::setprecision(6) << " " << f.readFloat32() << endl;
		f.seek(vertex_buffer_stride - 12, SEEK_REL);
		}
	out << endl;
	for (int i = 0; i < index_count; i++) {
		out << "f " << f.readInt16() + 1;
		out << " " << f.readInt16() + 1;
		out << " " << f.readInt16() + 1 << endl;
		}

	out.close();
    return 0;
	}

C#

Code: Select all

using System;
using System.IO;
using System.Text;

namespace ModelDumper {
    class Program {
        static int readShort(ref Byte[] buffer, ref int ptr) {
            // Converts Unsigned 16bit Integer from the buffer
            int word = (buffer[ptr++] & 0xFF) | ((buffer[ptr++] & 0xFF) << 8);
            return word;
            }
        static int readLong(ref Byte[] buffer, ref int ptr) {
            // Converts Unsigned 32bit Integer from the buffer
            int dword = (buffer[ptr++] & 0xFF) | ((buffer[ptr++] & 0xFF) << 8) | ((buffer[ptr++] & 0xFF) << 16) | ((buffer[ptr++] & 0xFF) << 24);
            return dword;
            }
        static double readFloat(ref Byte[] buffer, ref int ptr) {
            int inputAsInt = readLong(ref buffer, ref ptr);
            double fraction = 0.0F;
            for (int i = 0; i < 23; i++) {
                fraction += (1 & (inputAsInt >> ((23 - i) - 1))) * (Math.Pow(2, -(i + 1)));
                }
            int sign = -1;
            if (((inputAsInt >> 31) & 0x00000001) == 0) {
                sign = 1;
                }
            return (sign * (1 + fraction) * (Math.Pow(2, (((inputAsInt & 0x7F800000) >> 23) - 127))));
            }
        static void Main(string[] args) {
            
            // Open File into a FileStream
            string file = "C:\\Users\\Corey\\Videos\\Captures\\Vghd\\geo_veh_c_sec_wheel.xgm";
            var fs = new FileStream(file, FileMode.Open);
            var fsize = (int)fs.Length;
            var buffer = new byte[fsize];
            fs.Read(buffer, 0, fsize);
            fs.Close();
            
            int ptr = 0x1D8;
            
            int vertex_buffer_size = readLong(ref buffer, ref ptr);
            int index_buffer_size = readLong(ref buffer, ref ptr);
            
            // Calculate the Counts from Buffer Info
            int vertex_buffer_stride = 24;
            int index_buffer_stride = 2;
            int vertex_count = vertex_buffer_size / vertex_buffer_stride;
            int index_count = index_buffer_size / index_buffer_stride / 3;
            
            // Set Obj File
            string objfile = "o mesh\ng mesh\n\n";
            
            // Read The buffers
            int f1;
            int f2;
            int f3;
            ptr = 0x29C;
            for (int i = 0; i < vertex_count; i++) {
                objfile += "v " + (readFloat(ref buffer, ref ptr)).ToString("0.000000");
                objfile += " " + (readFloat(ref buffer, ref ptr)).ToString("0.000000");
                objfile += " " + (readFloat(ref buffer, ref ptr)).ToString("0.000000") + "\n";
                ptr += vertex_buffer_stride - 12;
                }
            objfile += "\n";
            
            for (int i = 0; i < index_count; i++) {
                f1 = readShort(ref buffer, ref ptr);
                f2 = readShort(ref buffer, ref ptr);
                f3 = readShort(ref buffer, ref ptr);
                objfile += "f " + (f1 + 1).ToString("0");
                objfile += " " + (f3 + 1).ToString("0");
                objfile += " " + (f2 + 1).ToString("0") + "\n";
                }
            
            // write the OBJ
            using (StreamWriter outputFile = new StreamWriter(Path.Combine(Path.GetDirectoryName(file), Path.GetFileNameWithoutExtension(file) + ".obj"), false)) {
                outputFile.WriteLine(objfile);
                }
            }
        }
    }

Visual Basics (Microsoft Excel VBA)

Code: Select all

Sub binToMesh()
    
    Dim file As String: file = "C:\\Users\\Corey\\Videos\\Captures\\Vghd\\geo_veh_c_sec_wheel.xgm"
    
    Dim F As Long: F = FreeFile
    Open file For Binary As F
    
    Seek F, 1 + &H1D8
    
    ' Reading Buffer Info
    Dim vertex_buffer_size As Long: Get F, , vertex_buffer_size
    Dim index_buffer_size As Long: Get F, , index_buffer_size
    
    
    ' Calculate the Counts from Buffer Info
    Dim vertex_buffer_stride As Long: vertex_buffer_stride = 24
    Dim index_buffer_stride As Long: index_buffer_stride = 2
    Dim vertex_count As Long: vertex_count = CLng(CSng(vertex_buffer_size) / CSng(vertex_buffer_stride))
    Dim index_count As Long: index_count = CLng(CDbl(index_buffer_size) / CDbl(index_buffer_stride) / 3#)
    
    
    ' Read The buffers
    Seek F, 1 + &H29C
    
    
    Dim objFile As String: objFile = "o mesh" + vbNewLine + "g mesh" + vbNewLine + vbNewLine
    Dim pos_x As Single, pos_y As Single, pos_z As Single
    Dim face_a As Integer, face_b As Integer, face_c As Integer
    
    Dim i As Long
    For i = 1 To vertex_count
        Get F, , pos_x
        Get F, , pos_y
        Get F, , pos_z
        objFile = objFile + "v " + Format$(pos_x, "0.000000")
        objFile = objFile + " " + Format$(pos_y, "0.000000")
        objFile = objFile + " " + Format$(pos_z, "0.000000") + vbNewLine
        Seek F, Seek(F) + (vertex_buffer_stride - 12)
    Next i
    objFile = objFile + vbNewLine
    
    For i = 1 To index_count
        Get F, , face_a
        Get F, , face_b
        Get F, , face_c
        objFile = objFile + "f " + CStr(face_a + 1)
        objFile = objFile + " " + CStr(face_c + 1)
        objFile = objFile + " " + CStr(face_b + 1) + vbNewLine
    Next i
    
    Close F
    
    ' Write Obj
    Open (file + ".obj") For Output As #1
    Print #1, objFile
    Close #1

End Sub

Here is the file that these programs work with:

geo_veh_c_sec_wheel.zip