ColumbusCMF

Columbus Model Format add-on for Blender, C library and console util for models conversion

The master hosted on github: https://github.com/ColumbusUtrigas/ColumbusCMF

Getting started

Columbus Model Format (CMF) developed for Columbus Engine. Engine needed fast, small, simple and and binary file format for containing 3-dimensional data.

C library was created for simple using CMF in applications (for example, CMF console util).

Console util was created for converting formats from most popular (FBX, OBJ) to CMF. Now it can't do this but I will develop this when there is free time.

Addon for Blender was created for simple saving models from blender into CMF. Now it just can't use compression.

File structure

CMF is very simple. It has 26-byte header, containing magic bytes and some parameters and data field, which can be compressed with ZSTD algorithm.

Header

Field	Size in bytes	Value	Description
Magic	21	string	File magic "COLUMBUS MODEL FORMAT"
Count	4	uint32	Count of polygons in model
Compression	1	uint8	Compression of data field, 0x00 - no, 0xFF - ZSTD compression

Data field

Part	Size in bytes	Description
Vertices	Count * 3 * 3 * sizeof(float)	Array of floats (XYZ, XYZ,...) with ALL vertices positions
UVs	Count * 3 * 2 * sizeof(float)	Array of floats (UV, UV,...) with ALL UV coordinates
Normals	Count * 3 * 3 * sizeof(float)	Array of floats (XYZ, XYZ,...) with ALL normal directions

C Library

C library cmf.h created for simple using CMF in applications.

Using

uint32_t Count;
CMF_Vertex* Vertices = CMF_Load("filename.cmf", &Count);
CMF_vec3 Pos;
CMF_vec2 UV;
CMF_vec3 Norm;

for (uint32_t i = 0; i < Count; i++)
{
	Pos = Vertices[i].Position;
	UV = Vertices[i].UV;
	Norm = Vertices[i].Normal;

	some_func1(Pos.X, Pos.Y, Pos.Z);
	some_func2(UV.X, UV.Y);
	some_func3(Norm.X, Norm.Y, Norm.Z);
}

int Result = CMF_Save(Count, 0xFF, Vertices, "out.cmf");

Documentation

To generate docs use

doxygen

Console util

Installing

make
sudo make install

Using

cmf [input] [output] [flags]

Console util flags

Flag	Description
-h, --help	Print help message
-c, --compress	Enable compression for output file
-v, --vertices	Enable writing vertices in output file
-t, --texcoords	Enable writing texture coordinates in output file
-n, --normals	Enable writing normals in output file

Uninstalling

sudo make uninstall