The OBJ file format is a simple data-format that represents 3D geometry alone — namely, the position of each vertex, the UV position of each texture coordinate vertex, the vertex normals, and the faces that make them up. Developed by Wavefront Technologies for their Advanced Visualizer animation package, it has been adopted by a wide range of 3D graphics applications. It is one of the industry's most established and widely supported formats for 3D models and is considered a de facto standard in the 3D industry.
How the OBJ Format Works
The OBJ format is text-based and very straightforward, which makes it easy to understand and work with. Each line of the file describes a different element of the object, be it a vertex, a texture coordinate, a vertex normal, or a face. One of the key features of the OBJ format is its support for complex geometries and high levels of detail. This has made it particularly popular for archiving and exchanging 3D models.
Software that Uses the OBJ Filetype
A wide array of software supports the OBJ filetype. This includes industry-standard 3D modeling tools such as Autodesk Maya, 3ds Max, and Blender. The universality of the format means that it is also compatible with various game engines, including Unity and Unreal Engine, allowing for seamless asset transfer between different development stages and platforms.
Alternatives to the OBJ Filetype
Despite its popularity, the OBJ format has limitations, particularly when it comes to storing animation data, scene information, or advanced lighting features. As a result, several alternatives have emerged, such as the FBX and COLLADA formats. These formats offer more features like embedding media, and supporting animation and application-specific custom data, providing a richer set of tools for complex projects.