vertexdata 1.0.1

For parsing obj files to be suitable to feed to a vertex buffer.

.obj to vertex data

The above spinning blahaj was rendered in a browser with typescript, see at alternyxx.com/blahaj! The model can be found here.

Intended Usage

The program aims to make .obj files with triangle data, for example,

v 1 0 0
v 0 1 0
v 0 0 1

vn 0.577 0.577 0.577

f 1//1 2//2 3//3

to

1, 0, 0, 0.5777, 0.5777, 0.5777,
0, 1, 0, 0.5777, 0.5777, 0.5777,
0, 0, 1, 0.5777, 0.5777, 0.5777,

This is for parsing obj files to be suitable to feed to a vertex buffer. For most cases, it'd be better to just use an index buffer though. If your .obj file has faces with quads, which is usually the case, eg.

f 1/1/1 2/1/1 3/1/1 4/1/1

Then, you could change your vertex buffer accordingly to have 4 vertex coordinates in the case the graphics api you're using supports quads. Else, there is github.com/StefanJohnsen/TriangulateOBJ-App to triangulate quads in a .obj file which is what I did for the blahaj!

Installation

pip

Make sure Python and pip is installed. Python version needs to be >= 3.10. Then run

pip install vertexdata

Build

In case pip is blocked (happens to me), you can simply clone the repository and build from scratch. This should be especially trivial as the project has 0 dependancies.

git clone https://github.com/alternyxx/vertexdata
cd vertexdata
pip install .

Command Line Usage

Once installed, you can run

vertexdata obj_file {target_file}

to get vertex data in the target_file. By default, the program will generate all given vertex data, positions, textures and normals if given. To override this, you can pass in

vertexdata obj_file {target_file} -nvn -nvt

to only generate the positions of the vertices. For more information, run

vertexdata --help

Library

If you want to parse the vertices in this way in a python project, you can

import vertexdata as vtd

def main():
    vertex_parser = vtd.VertexParser(
        source, target_file, no_normal_data=true, no_texture_data=true
    )
    vertex_parser.parse()
    your_vertices_data = vertexparser.output()

source can be a file which then you can do

vertexparser = vtd.VertexParser(
    source, target_file, read_file=true
)

If you don't need to output target as a file then you can pass an empty string. And, finally, there's the flags, no_normal_data and no_texture_data.