Geometry.fromBufferGeometry has an issue when reading InterleavedBuffer

Geometry.fromBufferGeometry produces wrong data when working with InterleavedBuffer

Assume we have a bufferGeometry with interleavedBufferAttribute as its attribute type.

There is an issue in geometry.js if we call Geometry.fromBufferGeometry(bufferGeometry). The current code assumes that the type of attribute is BufferAttribute, but it also can be InterleavedBufferAttribute, and they cannot be read in the same way.

For BufferAttribute, we read attribute like position, normal individually. But for InterleavedBufferAttribute, it returns a typed array that bundles all attributes together. So we need to read the data based on its offset and itemsize.

It might be better to support reading attribute individually in InterleavedBufferAttribute class, but at least we need a quick fix in the geometry method.

If you all think this is a bug and nobody is fixing it right now, I can open a PR. I can also create a jsfiddle if you think it’s necessary to demonstrate the wrong data output.

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r109
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Issue Analytics

State:
Created 4 years ago
Comments:8 (3 by maintainers)

Top GitHub Comments

1reaction

WestLangleycommented, Oct 23, 2019

If we have indices in triangle strip mode, the resulting faces could go wrong

Also see the discussion in https://github.com/mrdoob/three.js/issues/9869.

1reaction

WestLangleycommented, Oct 22, 2019

I can open a PR.

Sure, why not? I think WireframeGeometry supports interleaved buffers…

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