Adding `wobj` library as a dependency

Run this command in a terminal, in your project's directory:

cargo add wobj

To add it manually, edit your project's Cargo.toml file and add to the [dependencies] section:

wobj = "0.3.0"

The wobj library will be automatically available globally. Read the wobj library documentation.

Back to the crate overview.

Readme

wobj

Wavefront OBJ polygonal geometry and MTL material parser library.

OBJ parsing only supports polygonal geometry and ignores all other statements.
MTL parsing supports both the original spec and the PBR extensions.

Usage

To load an OBJ file:

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let bytes = std::fs::read("assets/cube.obj")?;
    let obj = wobj::Obj::parse(&bytes)?;

    // To get the meshes
    for mesh in &obj.meshes() {
        println!("Name: {:?}", mesh.name());

        // To triangulate the meshes
        let (indicies, verticies) = mesh.triangulate()?;
    }

    Ok(())
}

To load a material:

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let bytes = std::fs::read("assets/cube.mtl")?;
    let mtl = wobj::Mtl::parse(&bytes)?;
    let material: Option<&wobj::Material> = mtl.get("CubeMaterial");
    Ok(())
}

Since OBJ files can use a different MTL file for each material, if we want to load all used materials without wasting work:

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let obj_path = std::path::Path::new("assets/cube.obj");
    let parent_path = obj_path.parent().unwrap();

    // Load the OBJ
    let obj = wobj::Obj::parse(&std::fs::read(obj_path)?)?;
    // Use a HashMap to store loaded MTLs
    let mut mtls = std::collections::HashMap::new();

    // Iterate through all meshes in the OBJ
    for mesh in &obj.meshes() {
        // Check if the mesh has a material
        if let Some(mtllib) = mesh.mtllib()
            && let Some(material_name) = mesh.material()
        {
            // Load the MTL if it has not been loaded before
            if !mtls.contains_key(mtllib) {
                // MTL-lib path is relative to the OBJ file
                let mtl_path = parent_path.join(mtllib);
                let mtl = wobj::Mtl::parse(&std::fs::read(mtl_path)?)?;
                mtls.insert(mtllib, mtl);
            }

            // Get the material
            let material = mtls
                .get(mtllib)
                .and_then(|m| m.get(material_name))
                .expect("Material not found");

            // Use the material
            println!("Material '{material_name}': {material:?}");
        }
    }

    Ok(())
}

License

Licensed under either of

MIT License (LICENSE-MIT or https://opensource.org/licenses/MIT)
Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)

at your option.

Adding wobj library as a dependency

Adding `wobj` library as a dependency