Open 0xr.space, press Open and choose the .obj, its .mtl and its texture images together, or the folder or ZIP that holds them. The material library and the images it names are matched by path, and the model opens with its colours and textures on a computer, an Android phone or a Meta Quest. If a file the model names was not picked, a dialog headed Some files are missing lists it, with Choose files, Choose folder and Open anyway.
Only part of the MTL is read: the diffuse colour (Kd), transparency (d or Tr), shininess (Ns, turned into roughness) and the diffuse texture (map_Kd). Ambient and specular colours, bump and normal maps are dropped. Textures must be PNG, JPEG or WebP. An OBJ has no unit: one more than 1,000 units across is read as millimetres, one more than 100 as centimetres, anything smaller as metres.
A .mtl file holds only the materials. Choose the .obj file, with its .mtl and texture images.
Pick the .obj with Add. If its .mtl or textures were not picked with it, the file picker opens again, once for the material library and once more for the images it names.
Each object and group in the file becomes a part of its own, and faces of any number of sides are split into triangles, so the parts can be pulled apart.
No. It is read on the device, and nothing is sent to a server unless you create a share link yourself.