4B entity_count. 0 in empty files, 1 for most single objects, N>1 in opkg.hob files
4B simple offset to vertices/faces - doesn't work all the time. Probably useless?

16B name
4B facegroups offset
4B int ? 0x7C, 
4B int ? 0x88, 0xA8
12B zero?
4B int ? 94, 0xD4
4B int ? 98, 0x100
4B int ? 9C, 0x104
4B float ?:
    -bark_moon, cldcar: 1.0
    -sky, e_cor: 0.2 
    -wmvwing: 1.25
12B zero
5x4B floats ?
4B int ? -bark_moon, e_cor, towc: 0xA = 10
6x 4B float ?

2B number of facegroups? NOF
2B number of facegroups? NOF
facegoup definitions 
{
  offsets, names, floats
}  

4B 0xFFFFFFFF header end marker

NOF * facegroup/meshdef0 132B {
  4B int
  4B int
  4B int
  4B int
  4B int offset to meshdef1 + 4
  8B zero
  48B 3 * {
    4B float 1.0
    12B zero
  }
  4B int
  3 * 4B float
  3 * 4B float 1.0
  28B zero
}

NOF * facegroup/meshdef1 96B {
  4B int facedef end offset
  20B zero
  4B int vertices used
  8B zero
  4B int face def offset
  4B int vertex def offset
  52B zero
}
  
NOF * face block
{
  8B zero
  4B int filepos + 4
  4B int face count FC
  FC * face
  {
    4B int ?    
    1B int 46/49/4B
    1B int 51/71
    1B int 0C
    1B int block size / 4: A = 40B, 9 = 36, etc.
        if block size = 9, this is a triangle, else quad
    2B int zero?
    2B int texture/material index?
    4x 2B vertex indices, if triangle, the last index is zero. Vertex indices are relative to the face group
    x bytes until block size
  }
}

Vertices
{
  2B int X
  2B int Y
  2B int Z
  2B int ?
}