glTF File Format for 3D Model in A-Frame

What is glTF file format and why should we use it in A-Frame?

glTF (GL Transmission Format) is an open standard for 3D scenes and models that's designed for efficient runtime use. It's known as the "JPEG of 3D" because of its potential to become a widespread, ubiquitous format for 3D data, in the same way that JPEG is a widespread, ubiquitous format for 2D images. glTF is developed by the Khronos Group, an industry consortium that also develops WebGL, Vulkan, and other open standards.

The glTF format has several advantages over other 3D model formats like OBJ or FBX. glTF files are designed to be small and fast to load, and they include information about materials and animations, which OBJ files do not. glTF also supports PBR (physically-based rendering) materials, which offer more realistic rendering than traditional Phong or Lambert materials.

Conversion from other 3D model file

To convert a 3D model from another format like OBJ to glTF, you can use a tool like Blender or a standalone converter like obj2gltf.

With Blender:

1. Install Blender: Blender is a powerful, free, and open-source 3D modeling and animation software. You can download it from the official website.

2. Import your model: Open Blender, then go to File > Import and select the appropriate format (like .obj) to import your model.

3. Export as glTF: Once your model is imported, go to File > Export > glTF 2.0 (.glb/.gltf). Choose your settings in the export dialog, then click Export glTF 2.0.

With obj2gltf:

1. Install Node.js and NPM: These are required to install and run obj2gltf.

2. Install obj2gltf: You can install it by running npm install -g obj2gltf in a terminal or command prompt.

3. Convert your model: You can convert an OBJ file to glTF by running obj2gltf -i model.obj -o model.gltf.

Conversion from other 3D model file

You can use it in A-Frame by referencing it in the src attribute of an a-entity or a-model tag, like so:

<a-scene>

<a-entity gltf-model="url(model.gltf)"></a-entity>

</a-scene>

Just replace "url(model.gltf)" with the URL or path to your glTF file. If you're running A-Frame locally, this will be a relative path like "model.gltf" or "models/model.gltf". If you're hosting the model somewhere else, it will be a full URL like "https://example.com/model.gltf".

You can find more detail about A-Frame gltf-model component at https://aframe.io/docs/1.4.0/components/gltf-model.html