Repeated dynamic blob-generation and automatic USDZ conversion.

[Skyswimsky]

First off, English isn't my native language and it's kind of the first time I am posting something like this. So apologies if I screw something up.

I'm working on a project where the user creates dynamic models in three.js and can then look at them via AR, both export into the proper file format(gltf) and launch of AR is done with the click of a single button. I let model-viewers automatic USDZ conversion take care of iOS as the blob doesn't seem to work with the ios-src and quick-look.

The problem occurs when the user returns from quick-look, makes some changes to the model and then wants start again. While the proper android src is set, it still shows the old model for the iOS device. I have super limited debug capabilities for iOS myself.

I tried removing the ios-src as I thought maybe it's automatically set on the first time and thus doesn't update to the 'new model', but that isn't working.

Does anyone have any suggestions, please?

[uprealdigital]

That's a pretty interesting problem since I'm working on something similar where 3d models are dynamically created. Curious about what people have to say even though I don't have an answer to that myself.

EDIT: I'm actually seeing the issue right now just changing the glb file manually, the auto-generated usdz file doesn't get updated. This might be a caching issue... I'm looking into it.

EDIT 2: I tried deleting the website caches and deleting the history but I'm still getting the same old geometry. Not sure how to force Safari to update the USDZ model.

[elalish]

@Skyswimsky Thanks, but could you provide a link to the deployed URL of the site that demonstrates the problem? I don't want to build your repo myself 😂

We do cache models, and we do it by their URL. If you're making changes to the GLB outside of our scene graph API, I think you'll need to update the URL (maybe append a version number) so that MV knows it's new.

[Skyswimsky]

@elalish Here is a link to a Codesandbox with the problem: https://codesandbox.io/s/charming-chatelet-5j1cg?file=/src/index.js

And the URL of the Object changes at runtime, as it'll always generate a new ObjectURL when you start.

[elalish]

@Skyswimsky Why are you using three.js directly in addition to model-viewer? model-viewer already includes all the functionality you're writing; the whole point of our library is to save you from having to use three.js directly by abstracting it at a higher level.

[Skyswimsky]

@elalish Because I need it to create modular objects at runtime that are then exported. Using the Model-Viewer functionality to display the object in AR for iOS and Android devices.

[elalish]

Your code doesn't seem to interact with MV, so I think you'd be better off asking on the three.js forums. If you want to change an object's dimensions, export it and see it in AR, you can do all of that with MV directly, in which case we can help. If you have a more complicated use case in mind, please describe it, as this is how we figure out what to add to our API.