What does mean LODS?

[eolandro]

Hi
First of all. Thank you for your work!!

I'm working in extract models from Aeon Flux video game of xbox. The models are BFM but there are things that i can not understand.
That's why i want to understand Bloodrayne 2 models. Between this games are one year.

I was reading https://github.com/PavelSharp/br2proj/blob/main/br2proj/bfm.py#L16. But What does mean LODs?. In ghidra there are some string about deformable... But is missing for me.

PD.
Sorry for bad english

PD2
I'm Software developer, but no game developer...

[PavelSharp]

Hi, @eolandro!
Thanks for your interest in the project, and sorry for the late reply.

To answer your question. LODs stands for Levels of Detail. It's a popular term in game development, which refers to a technique where one file contains several versions of the same model with different polygon counts. The engine automatically switches between them based on certain parameters and reasons, basically the distance from the camera to save performance.

Regarding the BFM format in BloodRayne 2, this feature was likely unimplemented or not used. As I recall, the engine doesn't contain any logic (except for the assert) to support multiple LODs, which is why the LOD value is always 1 in every analyzed file (at least in the Windows version).

However, I'm interested to see if any Aeon Flux files actually have a LOD count higher than 1. If so, the geometry data should follow a consistent pattern for each level.

[eolandro]

hi, @PavelSharp !

Well to say the truth. it's not so different. it seems that LODs is still 1. Version is very different. it's about 3 parts of 32 bits each one.
For example in "models_aeon.bfm"

VERSION_0 = [0x0b,0x00,0x00,0x00]
VERSION_1 = [0x0b,0x00,0x00,0x00]
VERSION_2 = [0x02,0x00,0x00,0x00]
LODS = [0x01,0x00,0x00,0x00] 
NUM_PARTS = [0x0C,0x00,0x00,0x00]
NUM_BONES = [0x5D,0x00,0x00,0x00]
NUM_TEXT = [0x01,0x00,0x00,0x00]
NUM_MESH = [0x03,0x00,0x00,0x00] # i'm not sure
TAGS_1 = [0x01,0x00,0x00,0x00] # i'm not sure
BFM_NULL = [0x00,0x00,0x00,0x00]

By the way, Do you know what is TAGS?