glTF format

What is glTF?

glTF (GL Transmission Format) is an open-source 3D file format for efficient transmission and loading. It is designed to be the “JPEG of 3D” for runtime use.

Primary use cases

• Web & mobile 3D: The standard for 3D on the web, embedded in websites and web apps.
• Real-time applications: Used in game engines (Unity, Unreal) and real-time rendering for its fast load times.
• AR/VR: Ideal for mobile-based experiences due to its small file size and performance.
• Interoperability: A reliable format for transferring models between different 3D software applications.
• Visualization: Used in architecture, engineering, and e-commerce for interactive 3D models.

Advantages

• Efficient: Small file size and a structure optimized for GPU rendering. Minimizes processing needed at runtime.
• All-in-one: A .glb file can contain everything: geometry, materials, textures, animations, and cameras.
• PBR native: Full support for Physically-Based Rendering materials, ensuring consistent visual results across platforms.
• Open standard: Vendor-neutral, with widespread adoption across the industry, preventing vendor lock-in.

Limitations

• Delivery format: Not an editing format. It is designed for final use, not for saving project source files with layers or history.
• CAD incompatibility: Lacks support for precise CAD data, NURBS, and construction history. Not suitable for manufacturing.
• Feature gaps: Advanced features (e.g., procedural textures, certain shaders) require engine-specific extensions, which can hurt interoperability.

Use cases

• Sharing 3D models between different 3D modeling software programs and engines.
• 3D printing, allowing users to print high-quality 3D models directly from glTF files.
• Real-time rendering of 3D graphics in applications such as video games and online 3D visualization tools.
• 3D visualization and analysis in fields such as architecture, engineering, and construction.

Conclusion

glTF is the optimal format for showing 3D content, especially on the web and in real-time applications. It is not the best format for creating or engineering 3D content.