OBJ Runtime Models

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The Evergine.Runtime.OBJ NuGet package provides a powerful and efficient solution for dynamically loading OBJ models at runtime. It is designed for real-time 3D applications and integrates seamlessly into your Evergine projects.

Supported OBJ Features

The Evergine.Runtime.OBJ namespace includes a robust OBJ file loader that supports a comprehensive range of mesh and material features:

✅ Features

1. Geometry

• Vertices, normals, and UVs (texture coordinates)
• Supports:
  • Triangles and quads (auto-triangulated)
  • Arbitrary polygon faces
  • Multiple mesh groups per file

2. Basic Materials

• Supports .mtl files:
  • Ambient (Ka), Diffuse (Kd), and Specular (Ks) colors
  • Shininess (Ns) and transparency

3. PBR Materials

• Metallic–roughness and specular–glossiness workflows
• Support for roughness, metallic, and normal maps

4. Textures

• Diffuse/albedo, normal, specular/metallic, and emissive textures
• Common formats supported: PNG, JPG, BMP

5. Transparency

• Parses d and Tr values from .mtl for alpha transparency
• Automatic blend mode configuration

6. Points & Lines

• Point cloud and wireframe geometry support
• Renders v and l commands directly from .obj files

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Getting Started

To start using the Evergine.Runtimes.GLB or Evergine.Runtimes.STL libraries, simply install the NuGet package and use the following code to load your assets:

protected async override void CreateScene()
{    
    var model = await OBJRuntime.Instance.Read("MyModel.obj");

    var assetsService = Application.Current.Container.Resolve<AssetsService>();
    var entity = model.InstantiateModelHierarchy(assetsService);
    this.manager.EntityManager.Add(entity);
}

Custom Shader Support

By default, models are loaded using the Standard Effect (Evergine’s built-in shader). However, if you want to load models using your custom shader, you must pass an additional CustomMaterialAssigner function to the Read method:

protected async override void CreateScene()
{
    var assetsService = Application.Current.Container.Resolve<AssetsService>();

    var model = await OBJRuntime.Instance.Read("Models/orc.obj", this.CustomMaterialAssigner);

    var entity = model.InstantiateModelHierarchy(assetsService);
    this.Managers.EntityManager.Add(entity);
}

Samples

This OBJ loader has been extensively tested against the full Comprehensive 3D Models dataset, ensuring compatibility with a wide variety of real‑world meshes, materials, and topology cases. Below are a few representative screenshots of models loaded and rendered at runtime:

Some screenshots

Stanford Bunny was created by Greg Turk and Marc Levoy from multiple range scans of a real object using a Cyberware 3030 MS scanner.

The Atrium Sponza Palace in Dubrovnik, re-modeled by Frank Meinl at Crytek with inspiration from Marko Dabrovic's original.

This is the standard material test object provided with the Mitsuba renderer. we converted it to a single OBJ file and separated the backdrop.

This orc was originally created on zbrush and exported as obj file.