Point Cloud GLTF export issue

[ketourneau]

Hi,

We try to make a point cloud scanner in Unity.

We use arfoundation-densepointcloud and we export point cloud with gltfast.

Then we try to import gltf point cloud in https://gltf-viewer.donmccurdy.com/ or in https://threejs.org/editor/ but we got error :

THREE.GLTFLoader: Primitive mode unsupported: Points

We we look inside GLTFLoader.js you can see where error is throw :

• Error : https://github.com/mrdoob/three.js/blob/3a76bc7d212557422abe33525d2f3e44f79fb406/examples/js/loaders/GLTFLoader.js#L3318
• WEBGL_CONSTANTS : https://github.com/mrdoob/three.js/blob/3a76bc7d212557422abe33525d2f3e44f79fb406/examples/js/loaders/GLTFLoader.js#L1799

Inside GLTF if we modify :

"meshes": [
    {
      "name": "Point Cloud",
      "primitives": [
        {
          ...
          "mode": "Points"
        }
      ]
    }
  ]

by

"meshes": [
    {
      "name": "Point Cloud",
      "primitives": [
        {
          ...
          "mode": 0
        }
      ]
    }
  ]

We can open GLTF point cloud in any THREE.JS viewer. Primitive Mode MUST be integer : https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#_mesh_primitive_mode