I'm trying to reverse engineer a model format from an older Russian game (Pathologic) with limited success. It is a proprietary model format not recognized by any converters/editing tools (believe me, I've tried! someone on the fan forums confirmed this with the person behind the engine, also). I'd like to be able to read the models into a potential open-source recreation of the original engine. The original game uses Direct3D and is from 2005, so I read up on relevant docs to get a start. Unfortunately, it's not the "x" model format.
What I've got so far (for a simple mesh):
- Texture file name/location
- Number of faces and vertices
- UV coordinates for each vertex
- Vertex buffer
Things I'm struggling to understand (least to most important)
File header: what could it mean?
"Arbitrary" padding in the file: what could determine its size?
12-element float matrices. Could be transformation matrices without the last row - to use with homogenous coordinate systems, but there's 6 of them in a mesh with 4 vertices and 2 faces - isn't that too many?
Mysterious 4 bytes describing each vertex: some kind of a color format?
Mysterious sets of 3 32-bit floats repeating multiple times - what could it be?
Where could the vertex normals be stored?
Attached is a very simple mesh (way under 1kB) I'm studying before moving on to the more complex ones. I believe it to be a simple textured plane. I've started with a similar mesh that was in XY plane, this one seems to be oriented a bit more arbitrarily. Since it's a plane, I assume it has 4 vertices and 2 faces.
File's structure as far as I can understand it
- Header at 0x00.
- Texture Filename Length at 0x11 (16 characters here)
- 1 byte padding
- Texture filename (h2_door_DXT1.tex)
- 1 byte padding
- Number of vertices at 0x23 (4 vertices)
- Number of faces at 0x27 (2 faces)
- 12 bytes of recurring 3x 4-byte floats (first occurrence)
- Mysterious float
- 12 bytes of recurring 3x 4-byte floats (second occurrence)
- 12-element float matrix (transformation matrix?)
- 73 bytes of unknown data
- 12 bytes of recurring 3x 4-byte floats (third occurrence) at 0xC0
- Data for four vertices at 0xCC. For each vertex, there's 3x int16 for X,Y,Z coordinates, then, 4 mysterious bytes, finally, 2 32-bit floats for UV coordinates.
- Vertex buffer at 0x114. Two triangle descriptions, for each there's 3x int16 for the vertex IDs.
After that it becomes a mix of 12-element float matrices and the recurring 3x floats with some padding/magic numbers between them.
I'd appreciate any and all help with answering my questions/helping with the bullet points I'm struggling on. I could also provide other mesh examples as needed.
