The best suited 3D format for the genARate platform is the GLTF format.
GLTF supports meshes, physically based materials (that are derived from Disney’s popular “principled” shader model), image based lighting and animation.
The format is still in active development and thus results may vary, depending on the used software packages.
If the 3D data that is to be used for augmentation is in a NURBS format (for example .igs or .stp), it needs to be converted into polygons first. There are a variety of tools that can achieve this, for example 3ds Max, Rhino or PiXYZ. Popular export formats for further data processing after this step are, among others, .obj and .fbx.
If the input mesh is already in polygonal form, it can be easily converted to GLTF.
Download speed of the augmented content is a concern – the lower the size, the quicker the download is. Therefore, we recommend 3D data that includes a maximum of 500,000 polygons and a texture resolution of 2048×2048 pixels.
Tools and Exporters
There are various ways to export GLTF files. https://github.com/KhronosGroup/glTF#gltf-tools contains a list of tools to achieve this; in the course of our tutorials, we present 3 different ways how to export GLTF: Export with MS Paint 3D, Export via Blender and Export via 3ds Max.
Upload glTF 3D models to https://gltf-viewer.donmccurdy.com/ to test it. The website gives an overview of an uploaded 3D model together with the validation report. If there is an error on your model you will see the error message on a lower left corner.
If you have a problem uploading your zip file to the tool, you have to unzip it to get a folder with all individual assets inside in first hierarchy (.gltf file, .bin file, texture folder) and simply drag & drop the folder on the website.