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PLYLoader fails to parse PLYExporter output

See original GitHub issue

The error:

    TypeError: Cannot read property 'properties' of undefined
      33 |       .toEqual(plyData.toString('utf8'));
      34 | 
    > 35 |     const plyGeom = new THREE.PLYLoader().parse(plyData);
      36 |     expect(plyGeom.getAttribute('position').count)
      37 |       .toEqual(geom.vertices.length);
      38 |   });
      
      at parseASCII (node_modules/three/examples/js/loaders/PLYLoader.js:273:72)
      at Object.<anonymous>.THREE.PLYLoader.parse (node_modules/three/examples/js/loaders/PLYLoader.js:471:15)
      at _callee2$ (test/VFFLoader.test.js:35:43)

Here’s the repro.

    const plyData = await fixture('airway.vff.ply');
    expect(new THREE.PLYExporter().parse(exportMesh))
      .toEqual(plyData.toString('utf8'));

    const plyGeom = new THREE.PLYLoader().parse(plyData); // throws error
    expect(plyGeom.getAttribute('position').count)
      .toEqual(geom.vertices.length);

To test: (sorry for the annoying repro steps)

git clone git@github.com:CustomOrthopaedics/vff-loader.git
cd vff-loader
git checkout 766457
npm install
npm test

Issue Analytics

State:
Created 5 years ago
Comments:11 (2 by maintainers)

Top GitHub Comments

1reaction

gkjohnsoncommented, May 10, 2018

Hey @dbkaplun! It sounds like VFF is a point cloud format, which the ply exporter doesn’t currently handle. I’d be happy to help with updating the exporter so it does, though.

I’m not able to run the repro steps at the moment, but it looks like the error on import might be because the face count is exported as a fractional number, which is obviously bad (and should probably throw an error when exporting).

Ultimately the exporter should be updated to handle point data export by omitting the element and face property fields in the header. I think the right solution would be to exclude the face list completely when exporting geometry with no index array, but that gets a bit more complicated when exporting an Object3D hierarchy with multiple meshes of different types. At the very least I can add that to the list of limitations of the exporter.

I’ll have to think about how to handle multiple meshes a bit more and look into what the PLY format offers to support that. I’ll add a couple issues in the PLY exporter repo when I get a chance, as well.

Thanks! Garrett

1reaction

donmccurdycommented, May 1, 2018

Another option would be GLTFExporter -> GLTFLoader, both of which do support point data.